Dissertations / Theses: 'Cancer cell microenvironment'

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YOUSAFZAI, MUHAMMAD SULAIMAN. "Cancer cell mechanics and cell microenvironment: An optical tweezers study." Doctoral thesis, Università degli Studi di Trieste, 2016. http://hdl.handle.net/11368/2908097.

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Since cancer metastasis is a complex process, lot of research has been carried out to identify different hallmarks for its diagnosis and cure. Mechanical alterations in cancer cells during cell spreading to adjacent tissues and other organs of the body emerged as a prominent hallmark in the last decade. In this thesis we employed a mechanistic approach and used stiffness (elasticity) as a marker to study cell’s mechanical response in varying microenvironmental conditions. Cell– microenvironment mechanical interaction is a blend of cell-matrix and cell-cell interactions. Therefore we adopted an approach to study cells in the presence of their neighbouring cells as well as on compliant substrates at small forces (<10pN) using optical tweezers. The elastic modulus was calculated using the Hertz-model. We considered three breast cell lines as model, showing three phases of cancer progression: MDA-MB-231, a highly aggressive cell line belonging to the Basal cell-like phenotype; MCF-7, a less aggressive cancer cell line, belonging to the Luminal A cell-like phenotype; and HBL-100, a non-neoplastic cell line, derived from the milk of a Caucasian woman, normal control for breast basal-myoepithelial cells. Cell elasticity can be locally measured by pulling membrane tethers, stretching or indenting the cell using optical tweezers. We introduce a simple approach to perform cell indentation by axially moving the cell against a trapped microbead. Our scheme is similar to the AFM vertical cell indentation approach and can help to compare the quantitative results and thus complement AFM in a low force regime and loading rates. The elasticity trend of the three cell lines in isolated conditions showed that the aggressive MDA-MB-231 cells are significantly softer as compared to HBL-100 and MCF-7 cells. We demonstrate that stiffness measurements are sensitive to the cellular sub-regions as well as the interacting microenvironment. We probed the cells at three cellular sub regions: central (above nucleus), intermediate (cytoplasm) and near the leading edge. In isolated condition, all cells showed a significant regional variation in stiffness: higher at the center and fading toward the leading edge. However, the regional variation become statistical insignificant when the cells were in contact with other neighboring cells. We found that neighboring cells significantly alter cell stiffness: MDA-MB-231 becomes stiffer when in contact, while HBL-100 and MCF-7 exhibit softer character. Furthermore, we have studied the influence of substrate stiffness on cell elasticity by seeding the cells on Collagen and Polydimethylsiloxane (PDMS) coated substrates with varying stiffnesses to mimic extracellular (ECM) rigidities in vitro. PDMS polymer to crosslinker ratio was adjusted to 15:1, 35:1 and 50:1 corresponds to 173kPa, 88kPa and 17kPa respectively. These results show that cells adapt their stiffness to that of the substrate. Flexible substrates leads to reduced cell spreading morphological changes. Cells on complaint substrates are softer as compared to stiffness substrates. Our results demonstrates that the substrate stiffness influence not only cell spreading and motility, but also cell elasticity. Finally, from the 3D tracking of the bead probe we analyzed the lateral forces arising during the vertical indentation of the cell membrane during cell-bead interaction. We calculated and compared the elastic moduli resulting from the total and vertical forces for two breast cancer cell lines: MDA-MB-231 and HBL-100, showing that the differences are important and the total force should be considered.

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Hodkinson, Philip Simon. "Tumour microenvironment interactions of small cell lung cancer." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/4254.

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Small cell lung cancer (SCLC) is characterised by rapid growth, early metastatic spread and poor long-term survival. The tumour is initially sensitive to chemotherapy and thus objective response rates are high. Unfortunately, this response is often short-lived and SCLC recurs with acquired drug resistance, resulting in early patient death. Despite intensive chemo- and radiotherapy regimes survival has not improved significantly in 20 years. Prior research suggests a critical role for the tumour microenvironment in the pathogenesis of other cancers. Therefore, investigating interactions between SCLC cells and components of the tumour stroma may identify novel therapeutic targets. This thesis demonstrates that extracellular matrix (ECM) proteins present in the tumour microenvironment protect SCLC cells in vitro from chemo- and radiotherapy induced cell cycle arrest and apoptosis via cell surface β1 integrins. Pharmacological and genetic inhibition of phosphoinositol-3 kinase signalling abrogates this effect, defining a central role for this pathway in SCLC de novo drug resistance. Furthermore, the protective effect of ECM occurs without alteration in chemotherapy-induced DNA damage allowing SCLC cells to survive with new genetic defects. Integrin-mediated drug resistance has been shown to be important in other tumours and thus development of strategies to inhibit this pathway may yield new anti-cancer treatments. The design of targeted agents to down-regulate integrin-ECM interaction requires an in depth understanding of the intracellular signals that modulate integrin affinity. Two such pathways are investigated in this thesis. 1) H-Ras, a dominant suppressor of integrin affinity, acts in part through phosphorylation of Erk. Data presented here demonstrate that H-Ras also suppresses integrins through a phospholipase-C epsilon (PLCε)-dependent pathway, thus explaining discrepancies in prior data and confirming a physiological role for this recently identified phospholipase. 2) The Notch signalling pathway has been shown to have important roles in both development and cancer. It is shown here that activation of Notch signalling increases β1 integrin affinity and can protect SCLC cells from chemotherapyinduced apoptosis. However the mechanisms appear to be different; Notch-1 modulates integrin activation through the small GTPase R-Ras and Notch-2 promotes SCLC cell survival. These results define a new Notch pathway, a novel integrin modulator and a potential therapeutic target in SCLC cells. In addition to ECM proteins, the tumour microenvironment contains immune cells that may contribute to cancer growth. The cellular composition of the SCLC stroma is poorly understood. The data presented here indicate that the microenvironment of SCLC is infiltrated by lymphocytes and macrophages, the degree of which independently predicts patient survival. This suggests that the host immune system may be able to suppress SCLC growth. It is well recognised that patients with SCLC have defects in cellular immunity which correlate with survival. An in vitro coculture model was used to investigate the underpinning mechanisms, showing SCLC cells can suppress CD4+ T-cell proliferation and macrophage CD86 expression. Furthermore, preliminary data suggest a role for a soluble factor released by SCLC cells that up-regulates CD4+ T-cell production of IL-10. The work in this thesis implies a complex interaction between SCLC cells, ECM and immune cells in the tumour microenvironment. Manipulation of these pathways may have important therapeutic implications. Further investigation is required to understand the mechanisms of this interplay, which may in part be aided by prospective analysis of patient tumour samples and an in vivo model of SCLC.

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Fong, Jenna. "Breast cancer cells affect bone cell differentiation and the bone microenvironment." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104758.

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Breast carcinoma is the most commonly diagnosed cancer among women worldwide, with approximately 1 in 7 expected to be affected during her lifetime. The spread of breast cancer to secondary sites is generally incurable. Bone is the preferred site of metastasis, where the development of a secondary tumour causes severe osteolysis, hypercalcemia and a considerable pain burden. However, how breast cancer cells establish supportive interactions with bone cells is not well understood. We have examined the effects of factors released from MDA-MB-231 and 4T1 breast cancer cells on the differentiation of C57BL6 mouse bone marrow cells. Treatment with cancer-derived factors resulted in a sustained 40–60% decrease in osteoblast differentiation markers, and induced an osteoclastogenic change in the ratio of receptor activator of NF-κB ligand (RANKL) to osteoprotegerin (OPG). Importantly, exposure of bone cells to breast cancer-derived factors stimulated the subsequent attachment of cancer cells to immature osteoblasts. Inhibition of γ-secretase using pharmacological inhibitors DAPT and Compound E completely reversed cancer-induced osteoclastogenesis as well as cancer-induced enhancement of cancer cell attachment, identifying γ-secretase activity as a key mediator of these effects. We next evaluated the effects of breast cancer cells on the energy metabolism of bone cells. Treatment of bone marrow cells with conditioned medium from 4T1 breast cancer cells resulted in an increase in glucose consumption by bone cells, higher mitochondrial transmembrane potential, and a 2.3-fold rise in cellular ATP content. In addition, breast cancer derived factors stimulated the expression of mRNA and protein levels of metabolic sensor, AMP-regulated protein kinase (AMPK). To assess if such change in cell bioenergetics may have consequences for cell differentiation and activity, we used defined models of osteoclastogenesis, and increased precursor metabolic activity by providing excess energy substrates. We have found that an increase in mitochondrial transmembrane potential and cellular ATP levels during osteoclastogenesis resulted in the formation of larger osteoclasts that demonstrate higher resorptive activity. Thus, we have uncovered that osteoblasts act as a critical intermediate of premetastatic signalling by breast cancer cells, and pinpointed γ-secretase as a robust target for developing therapeutics potentially capable of reducing both the homing and progression of cancer metastases to bone. In addition, we have discovered heightened energetics in bone cells exposed to breast cancer cell-released factors, which may contribute to the formation of larger, more active osteoclasts. Modification of the AMPK pathway may prove an important therapeutic target for breast cancer metastasis to bone.
Le cancer du sein est le cancer plus diagnostiqué chez les femmes. On estime qu'environ une femme sur sept en sera affectée. La diffusion du cancer du sein aux emplacements secondaires est généralement incurable. L'os est l'emplacement préféré de la métastase, où le développement d'une tumeur secondaire cause de l'osteolyse, de l'hypercalcemie, et une douleur considérable. Cependant, comment les cellules de cancer du sein établissent des interactions supportifs avec des cellules d'os n'est pas bien compris. Nous avons examiné les effets des facteurs libérés des cellules du cancer du sein MDA-MB-231 et 4T1 sur la différentiation des cellules de moelle de la souris C57BL6. Le traitement avec des facteurs cancer-dérivés a produit une diminution de 40-60% des marqueurs de différentiation d'osteoblast, comparé au traitement par l'acide ascorbique, et a induit un changement osteoclastogenique dans le rapport du RANKL/osteoprotegerin. L'exposition des cellules d'os à des facteurs dérivés du cancer du sein a ensuite stimulé l'attachement des cellules cancéreuses aux osteoblasts non mûrs. L'inhibition du γ-secretase utilisant les inhibiteurs pharmacologiques DAPT et le Compound E a complètement inversé l'osteoclastogenise cancer-induit aussi bien que le perfectionnement cancer-induit de l'attachement de cellules cancéreuses, identifiant l'activité de le γ-secretase comme étant le médiateur principal de ces effets. Nous avons ensuite évalué les effets des cellules cancereuse sur le métabolisme énergétique des cellules d'os. Le traitement des cellules de moelle avec le medium conditionné des cellules du cancer du sein 4T1 a eu comme conséquence une augmentation des mitochondries à haut-potentiel de membrane, une augmentation de 2.3 fois le contenu cellulaire de triphosphate d'adénosine, et une consommation plus rapide du glucose. Ce changement de l'énergétique a été accompagné d'une stimulation d'AMPK dans la protéine et l'ADN messagère. Pour évaluer les effets du statut de haute énergie dans les osteoclasts, nous avons élevé l'énergique des osteoclasts avec du pyruvate de sodium. Cette addition a causée une croissance des osteoclasts, avec des plus grands nucleus, et la résorption de plus de substrat. Ainsi, nous avons découvert l'osteoblast comme étant un intermédiaire clé à la signalisation prémetastatique par des cellules du cancer du sein. Nous avons aussi indiqué le γ-secretase comme cible robuste pour le developpement de thérapeutique potentiellement capable de réduire l'autoguidage et la progression des métastases de cancer à l'os. Additonellement, nous avons découvert l'énergétique intensifiée chez les cellules d'os exposées aux facteurs cellule-libérés par le cancer du sein, qui mène à une osteoclastogenesise plus active et plus importante. La modification de la voie d'AMPK peut s'avérer être une cible thérapeutique importante pour que la métastase de cancer du sein aux os.

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Daukšte, Liene. "Mathematical Modelling of Cancer Cell Population Dynamics." Thesis, University of Canterbury. Mathematics and Statistics, 2012. http://hdl.handle.net/10092/9356.

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Mathematical models, that depict the dynamics of a cancer cell population growing out of the human body (in vitro) in unconstrained microenvironment conditions, are considered in this thesis. Cancer cells in vitro grow and divide much faster than cancer cells in the human body, therefore, the effects of various cancer treatments applied to them can be identified much faster. These cell populations, when not exposed to any cancer treatment, exhibit exponential growth that we refer to as the balanced exponential growth (BEG) state. This observation has led to several effective methods of estimating parameters that thereafter are not required to be determined experimentally. We present derivation of the age-structured model and its theoretical analysis of the existence of the solution. Furthermore, we have obtained the condition for BEG existence using the Perron- Frobenius theorem. Amathematical description of the cell-cycle control is shown for one-compartment and two-compartment populations, where a compartment refers to a cell population consisting of cells that exhibit similar kinetic properties. We have incorporated into our mathematical model the required growing/aging times in each phase of the cell cycle for the biological viability. Moreover, we have derived analytical formulae for vital parameters in cancer research, such as population doubling time, the average cell-cycle age, and the average removal age from all phases, which we argue is the average cell-cycle time of the population. An estimate of the average cell-cycle time is of a particular interest for biologists and clinicians, and for patient survival prognoses as it is considered that short cell-cycle times correlate with poor survival prognoses for patients. Applications of our mathematical model to experimental data have been shown. First, we have derived algebraic expressions to determine the population doubling time from single experimental observation as an alternative to empirically constructed growth curve. This result is applicable to various types of cancer cell lines. One option to extend this model would be to derive the cellcycle time from a single experimental measurement. Second, we have applied our mathematical model to interpret and derive dynamic-depicting parameters of five melanoma cell lines exposed to radiotherapy. The mathematical result suggests there are shortcomings in the experimental methods and provides an insight into the cancer cell population dynamics during post radiotherapy. Finally, a mathematical model depicting a theoretical cancer cell population that comprises two sub-populations with different kinetic properties is presented to describe the transition of a primary culture to a cell line cell population.

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Truong, Danh, Julieann Puleo, Alison Llave, Ghassan Mouneimne, Roger D. Kamm, and Mehdi Nikkhah. "Breast Cancer Cell Invasion into a Three Dimensional Tumor-Stroma Microenvironment." NATURE PUBLISHING GROUP, 2016. http://hdl.handle.net/10150/621806.

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In this study, to model 3D chemotactic tumor-stroma invasion in vitro, we developed an innovative microfluidic chip allowing side-by-side positioning of 3D hydrogel-based matrices. We were able to (1) create a dual matrix architecture that extended in a continuous manner, thus allowing invasion from one 3D matrix to another, and (2) establish distinct regions of tumor and stroma cell/ECM compositions, with a clearly demarcated tumor invasion front, thus allowing us to quantitatively analyze progression of cancer cells into the stroma at a tissue or single-cell level. We showed significantly enhanced cancer cell invasion in response to a transient gradient of epidermal growth factor (EGF). 3D tracking at the single-cell level displayed increased migration speed and persistence. Subsequently, we analyzed changes in expression of EGF receptors, cell aspect ratio, and protrusive activity. These findings show the unique ability of our model to quantitatively analyze 3D chemotactic invasion, both globally by tracking the progression of the invasion front, and at the single-cell level by examining changes in cellular behavior and morphology using high-resolution imaging. Taken together, we have shown a novel model recapitulating 3D tumor-stroma interactions for studies of real-time cell invasion and morphological changes within a single platform.

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Giraldo-Castillo, Nicolas. "The Immune Microenvironment in Clear Cell Renal Cell Carcinoma : The heterogeneous immune contextures accompanying CD8+ T cell infiltration in clear cell Renal Cell Carcinoma." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066321/document.

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Dans cette étude, nous avons tenté de décrypter les mécanismes reliant l’augmentation de lymphocytes infiltrant les tumeurs (LIT) T CD8+ et un pronostic clinique défavorable dans le cancer du rein à cellules claires (ccRCC). Pour cela, nous avons déterminé 1) la relation entre le pronostic associé à l'expression d’immune checkpoints et l’infiltrat de cellules dendritiques (DC) et de LT CD8+ et 2) les caractéristiques phénotypiques des LIT T CD8+. L’expression des immune checkpoints a été déterminée par immunohistochimie dans une cohorte de 135 ccRCC. Nous avons constaté que les densités des cellules exprimant CD8, PD-1 et LAG-3 sont corrélées, et associées à une diminution de PFS et OS. Egalement, les patients dont les tumeurs présentent des densités élevées de cellules PD-1+ et PD-L1 et/ou PD-L2 +, ont le taux de survie le plus faible. Des densités élevées de DC immatures isolées dans le stroma tumoral sont associées à une forte expression d’immune checkpoints et à un faible taux de survie chez ces patients. En revanche, les patients présentant un taux de survie prolongé ont une densité élevée de lymphocytes CD8+, des DC matures au sein de structures lymphoïdes tertiaires, ainsi qu’une faible expression d’immune checkpoints. Nous avons analysé les LIT T CD8+ chez 21 patients ccRCC par Cytométrie de Flux. On a trouvé un groupe de patients (8/21) dont les tumeurs sont caractérisées par la surexpression de marqueurs inhibiteurs (PD1 et TIM3) et de d'activation (CD69 et CD38), par l'expansion des cellules T CD8 + mémoires effectrices et un plus grand potentiel d’agressivité. En résumé, nous avons démontré qu’une densité élevée de LIT T CD8+ dans les ccRCC est accompagnée d’une forte expression d’immune checkpoints et d’une réponse immunitaire mal coordonnée dans un sous-groupe de tumeurs agressives
To decipher the potential mechanisms linking increased CD8+ T cell infiltration with an adverse clinical outcome in ccRCC, in this study we determined: 1) the prognosis associated with the expression of immune checkpoints and its coordination with dendritic cell (DC) and CD8+ cell infiltration, and 2) the phenotypic traits of CD8+ tumor infiltrating lymphocytes. The prognosis associated with CD8+ and DC infiltrations, in addition to the expression of immune checkpoints were investigated in a cohort of 135 ccRCC by quantitative immunohistochemistry. We found that the densities of CD8+, PD-1+ and LAG-3+ cells were closely correlated, and independently associated with decreased PFS and OS. In addition, patients whose tumors presented both high densities of PD-1+ cells and PD-L1+ and/or L2+ tumor cells, displayed the worst clinical outcome. High densities of immature DC isolated in the tumour stroma were associated with high expression of immune checkpoints and patients’ poor clinical outcome. In contrast, the presence of mature DC within Tertiary Lymphoid Structures identified, among the tumours with high CD8+-TIL densities, those with low expression of immune checkpoints and prolonged survival. We also investigated the phenotype of freshly isolated CD8+TIL in 21 ccRCC by flow cytometry. We found a group tumors (8/21) characterised by the over-expression of inhibitory (PD-1 and TIM-3) and activation markers (CD69 and CD38), the expansion of the effector memory cell subpopulation (CCR7-CD45RA-), and a trend toward more aggressive features. In summary, we demonstrated that the infiltration with CD8+ TIL in ccRCC is accompanied by the enhanced expression of immune checkpoints and a poorly coordinated immune response in a subgroup of aggressive tumors

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Xing, Fei. "ROLE OF NOTCH SIGNALING IN BREAST CANCER METASTASIS." OpenSIUC, 2012. https://opensiuc.lib.siu.edu/dissertations/514.

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Notch signaling is often and aberrantly activated by hypoxia during tumor progression; however, the exact pathological role of hypoxia-induced Notch signaling in tumor metastasis is as yet poorly understood. In the first part of this study, we aimed to define the mechanism of Notch ligand activation by hypoxia in both primary tumor and bone stromal cells in the metastatic niche and to clarify their roles in tumor progression. We have analyzed the expression profiles of various Notch liagnds in 779 breast cancer patients in GEO database and found that the expression of Jagged2 among all five ligands is most significantly correlated with the overall- and metastasis-free survival of breast cancer patients. The results of our immunohistochemical (IHC) analysis for Jagged2 in 61 clinical samples also revealed that both Jagged2 and Notch signaling were strongly up-regulated at the hypoxic invasive front. Activation of Jagged2 by hypoxia in tumor cells induced EMT and also promoted cell survival in vitro. Notably, a ã-secretase inhibitor significantly blocked Notch-mediated invasion and survival under hypoxia by promoting expression of E-cadherin and inhibiting Akt phosphorylation. Importantly, Jagged2 was also found to be up-regulated in bone marrow stroma under hypoxia and promoted the growth of cancer stem-like cells by activating their Notch signaling. Therefore, hypoxia-induced Jagged2 activation in both tumor invasive front and normal bone stroma plays a critical role in tumor progression and metastasis, and Jagged2 is considered to be a valuable prognostic marker and may serve as a novel therapeutic target for metastatic breast cancer. In the second part of this study, the role of Notch signaling in brain metastasis was investigated. Metastatic diseases are responsible for the majority of the deaths in breast cancer patients and the brain is one of the most common metastatic sites. The metastatic tumor in the brain profoundly affects the cognitive and sensory functions as well as morbidity of patients, and the one year survival rate among these patients remains less than 20%. However, the pathological mechanism of brain metastasis is as yet poorly understood. In this report, we found that metastatic breast tumor cells in the brain highly expressed IL-1â which can "activate" astrocytes. This activation significantly augmented the expression of JAG1 in the reactive astrocytes, which in turn activated Notch signaling pathway of cancer stem-like cells (CSCs) upon direct interaction. We also found that the activated Notch signaling in CSCs up-regulated Sox2 followed by promoting self-renewal of CSCs. Furthermore, we have shown that the blood-brain barrier permeable Notch inhibitor, Compound E, can significantly suppress the brain metastasis growth in our animal model. These results represent a novel paradigm for the understanding of how metastatic breast CSCs re-establish their niche for their self-renewal in a totally different microenvironment, which opens a new avenue to identify a novel and specific target for the brain metastatic disease

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Kaira, Mustapha. "In situ molecular profilling of the microenvironment of breast carcinoma." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-265258.

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High stromal PDGF receptor B expression was shown to have strong prognostic value in a studyinvolving over 600 breast cancer patients however, the molecular role of the receptor in tumordevelopment remains unclear. In this project we studied the spatial distribution and expressionlevels of a panel genes and markers associated with PDGF signaling, in breast cancer tumormicroenvironment (TME) using a newly developed technique -in situ sequencing. The techniquerelies on padlock probes which we validated with corresponding RNA sequencing, microarray,and immunohistochemistry data. Our results showed that high PDGF receptor B mRNA colocalizedwith markers of two pathways, TGFβ and Hedgehog signaling; this suggests that theymight contribute to the PDGF-receptor B-driven tumor growth. We also showed that stromalPDGF signaling is stimulated predominantly by tumor cells. Finally, further expression profilingof each individual gene revealed that CXCL14 was mainly expressed in the stroma, ACTA2expression was enriched in the tumor/stroma boundary while the stem-cell marker, OCT3, wasexpressed in the interior of the tumor cells.

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Kiyasu, Yoshiyuki. "Disruption of CCR1-mediated myeloid cell accumulation suppresses colorectal cancer progression in mice." Kyoto University, 2020. http://hdl.handle.net/2433/259008.

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Sundquist, E. (Elias). "The role of tumor microenvironment on oral tongue cancer invasion and prognosis." Doctoral thesis, Oulun yliopisto, 2018. http://urn.fi/urn:isbn:9789526217659.

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Abstract Oral tongue squamous cell carcinoma (OTSCC) is the most common cancer of the oral cavity. The 5-year mortality of OTSCC remains at about 50%. The tumor microenvironment (TME) is now recognized as an important factor in cancer progression and metastasis, as well as a tool for prognostication. The aim of this study was to elucidate the roles of TME hypoxia and soluble factors on cancer cell migration and invasion, and the prognostic value of two extracellular matrix (ECM) molecules: tenascin-C (TNC) and fibronectin (FN). Hypoxia was studied using oral squamous cell carcinoma cells in migration and invasion assays. Invasion assays were carried out using a 3D-myoma invasion method. Similarly, the effect of soluble factors as well as ECM alterations were studied using the myoma model: the effect of soluble factors was studied by rinsing the myoma discs prior to experiments, and ECM alterations by lyophilizing and rehydrating. ECM was further studied by analyzing the prognostic value of TNC and FN from OTSCC samples. The effect of hypoxia was shown to be OTSCC cell line dependent: the effect of hypoxia on migration and invasion was increased in aggressive cell lines. Additionally, the response to hypoxia was altered in rinsed tissue. Tissue rinsing media were analyzed and factors affecting cell motility were found. The TME was found to be pivotal for cancer invasion: invasion was impaired in non-neoplastic tissue. Furthermore, changes in the ECM by lyophilization and rehydration led to a change in the invasion mechanism. High expression of stromal TNC and FN were excellent prognosticators in early-stage OTSCC. In conclusion, the present study highlighted the role of various TME components in cancer cell invasion as well as prognostication in OTSCC. Additionally, this study provided feasible tools for more precise diagnosis of early-stage OTSCC
Tiivistelmä Liikkuvan kielen levyepiteelikarsinooma (OTSCC) on suuontelon yleisin syöpä. Viiden vuoden kuolleisuus OTSCC:an on edelleen noin 50 %. Kasvaimen mikroympäristön (TME) tiedetään nykyään olevan tärkeässä roolissa syövän kehityksessä ja etäpesäkkeiden muodostuksessa, sekä tarjoavan työkaluja ennusteiden laadintaan. Tämän tutkimuksen tarkoituksena oli selvittää TME:n hypoksian ja liukoisten tekijöiden vaikutusta syöpäsolujen liikkumiseen ja invaasioon ympäröivään kudokseen, sekä tutkia kahden solunulkoisen matriksin (ECM) proteiinin, tenaskiini-C:n (TNC) ja fibronektiinin (FN), vaikutusta OTSCC:n ennusteeseen. Hypoksian vaikutusta tutkittiin käyttäen suun levyepiteelikarsinoomasoluja liikkuvuus- ja invaasiokokeissa. Invaasiokokeissa hyödynnettiin kolmiulotteista ihmisen myoomaan perustuvaa invaasiomallia. Myös liukoisten tekijöiden ja ECM:n muutosten vaikutusten tutkimisessa käytettiin myoomamallia: liukoisten tekijöiden vaikutusta tutkittiin huuhtomalla myoomakiekot ennen niiden käyttämistä, ja ECM:n muutosten vaikutusta kylmäkuivaamalla ja uudelleen nesteyttämällä myoomakiekot. ECM:ia tutkittiin myös analysoimalla TNC:n ja FN:n värjäytyvyyden merkitystä OTSCC:n ennusteessa. Hypoksian vaikutus osoittautui solulinjariippuvaiseksi: hypoksia lisäsi kielisyöpäsolujen liikkuvuutta ja invaasiota eniten aggressiivisimmilla solulinjoilla. Lisäksi solujen vaste hypoksialle oli erilainen huuhdotussa kudoksessa. Huuhteluliuos analysoitiin ja siitä löydettiin solujen liikkumiseen vaikuttavia tekijöitä. TME:n havaittiin olevan ratkaisevassa roolissa syöpäsolujen invaasiossa: syöpäsolut eivät kyenneet invasoitumaan lainkaan ei-neoplastiseen kudokseen. Lisäksi muutosten ECM:ssä havaittiin johtavan muutoksiin solujen käyttämässä invaasion mekanismissa. Strooman TNC:n ja FN:n värjäytyvyyden todettiin olevan erinomaisia ennustekijöitä aikaisen vaiheen OTSCC:ssa. Tiivistettynä voidaan todeta, että tämä tutkimus alleviivasi useiden TME:n komponenttien vaikutusta syövän invaasiolle ja ennusteelle OTSCC:ssä. Lisäksi se tarjoaa käyttökelpoiset työkalut (TNC ja FN) tarkemmalle diagnostiikalle aikaisen vaiheen OTSCC:ssä

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Wang, Yuan Yuan. "Deciphering the crosstalk between breast cancer cells and tumour-surrounding apidocytes : contribution of cell metabolic symbiosis." Toulouse 3, 2013. http://thesesups.ups-tlse.fr/2093/.

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Relativement peu d'attention a été accordée aux adipocytes matures qui représentent le type cellulaire majoritaire entourant le cancer du sein. Le rôle des adipocytes dans la progression tumorale est devenu d'une importance clinique majeure depuis qu'il a été montré que l'obésité est un facteur indépendant de mauvais pronostic dans le cancer du sein. Au cours de ma thèse, j'ai participé aux efforts de mon équipe visant à caractériser les changements phénotypiques induits par les cellules tumorales dans les adipocytes environnants la tumeur. Nous avons ainsi défini deux nouvelles populations de cellules stromales dérivées des adipocytes, les Cancer-Associated Adipocytes (CAAs) (présents au front invasif de la tumeur) et les Adipose-Derived Fibroblasts (ADFs) (retrouvés au centre de la tumeur) qui stimulent l'invasion tumorale localement et à distance de la tumeur. Durant ma thèse, j'ai montré qu'une symbiose métabolique s`établit entre les cellules cancéreuses et les CAAs. Les acides gras libres dérivés des adipocytes (AGLs), captés et stockés par les cellules cancéreuses mammaires, sont utilisés pour la bêta-oxydation de lipids. Les cellules tumorales doivent posséder une voie lipolytique couplée pour utiliser les stockés à la fois in vitro et dans des tumeurs humaines. Nos résultats mettent en évidence le rôle important et plutôt inattendu de la bêta-oxydation dans l'invasion des cellules tumorales in vitro et in vivo. Dans l'ensemble, mon travail montre le rôle clé des adipocytes environnants dans l'augmentation de l'agressivité du cancer du sein et les mécanismes moléculaires impliqués
Relatively little attention has been given to mature adipocytes which are the most abundant cell type surrounding breast cancer. Role of adipocytes in tumor progression might be of major clinical importance since obesity has been shown to be a poor independent prognosis factor for breast cancer. During my Ph. D. , I participated to the efforts of my team to characterize the phenotypical changes induced by tumor cells in surrounding adipocytes. We defined two new stromal cell population derived from adipocytes, Cancer-Associated Adipocytes (CAAs) (present at tumor invasive front) and Adipose-Derived Fibroblast (ADFs) (found in the tumor centre) that stimulate tumor local and distant invasion. During my thesis, I have shown that a metabolic symbiosis is established between cancer cells and CAAs. The adipocytes-derived free fatty acids (FFAs) are uptaken and stored by breast cancer cells to be used for fatty acid beta-oxidation (FAO). Tumor cells need to possess a coupled lipolytic pathway to use the stored FFAs as depicted herein both in vitro and in human tumors. Our results highlight the important and rather unexpected role of FAO in tumor cell invasion in vitro and in vivo. Taken together, my work show the key role of surrounding adipocytes in increasing the aggressiveness of breast cancer and the molecular mechanisms involved

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Wang, Elaine. "Warburg or reverse Warburg effect: Tumor microenvironment reprograms breast cancer metabolism to upregulate cell proliferation." Scholarship @ Claremont, 2018. http://scholarship.claremont.edu/cmc_theses/1966.

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Cancer cells are most clearly characterized by their abnormal and uncontrolled cell growth. One of the most notable theories that explains the vast proliferative capacity of tumorigenic cells is the Warburg effect, a significant shift in metabolism wherein cancer cells preferentially fuel cell division using aerobic glycolysis instead of aerobic respiration. This upregulation of glycolytic fermentation in aerobic environments is highly unusual - glycolysis is typically utilized in anaerobic conditions, but nonetheless dominates cancer metabolic activity in spite of the presence of oxygen. Since the discovery the Warburg effect in the 1920s, researchers have struggled to identify whether aerobic glycolysis is a cause or consequence of carcinogenesis. Interestingly, a new theory recently emerged that challenges this widely-accepted metabolic paradigm for cancer. Known as the reverse Warburg effect, this new mechanism shows that in carcinomas such as breast cancer, the Warburg effect occurs not in cancer cells, but rather in tumor-adjacent stromal fibroblasts. These cancer-associated fibroblasts (CAFs) in the greater tumor microenvironment produce lactate - a high-energy metabolite formed as a byproduct of aerobic glycolysis - to fuel aerobic respiration and rapid tumorigenesis in neighboring cancer cells. This emerging theory emphasizes the pivotal role of the tumor microenvironment in determining whether cancer cells undergo aerobic glycolysis or aerobic respiration. Central to this lactate-linked metabolic intersection are two critical enzymes that regulate a cell's metabolic commitment - lactate dehydrogenase (LDH) and pyruvate dehydrogenase complex (PDHc). In order to clarify the mechanisms through which CAFs induce tumorigenesis in breast cancer, we plan to carry out two specific aims: (1) evaluate the enzymatic activity of LDH and PDHc, and (2) compare LDH and PDHc enzyme content. Using co-culture techniques to study the breast cancer tumor microenvironment in vitro, we will compare the enzymatic activity and enzyme content of both MCF7 breast cancer cells and CAFs to identify whether the reverse Warburg effect occurs due to post-translational enzyme activation or increased enzyme synthesis.

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Hoffmann, Caroline. "Dendritic Cells in Head and Neck Cancer Microenvironment : From Mechanisms to Biomarkers." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS308/document.

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L’objectif de ce travail était de comprendre l’état moléculaire des cellules dendritiques (CD) dans le microenvironnement tumoral. En intégrant l’analyse de tumeurs humaines par cytométrie en flux, de transcriptome, de secretome tumoral et l’analyse d’une base de données d’interaction CD-lymphocyte T générées in vitro, j’ai obtenus 2 résultats majeurs. Tout d’abord, nous proposons une nouvelle classification de CD activées humaines, qui sont soit « secrétantes », c’est-à-dire spécialisées dans la production de cytokines et chemokines, soit « aidantes » c’est-à-dire spécialisées dans l’induction de la sécrétion de nombreuses cytokines T helper après co-culture. Les CD infiltrant les tumeurs ORL inflammées correspondaient au type « sécrétantes ». Au-delà du nouveau concept biologique, cette classification est base théorique importante pour l’immunothérapie à base d’adjuvants. Deuxièmement, nous avons montré que l’inflammation tumorale n’était pas un facteur pronostic majeur des cancers ORL, mais que MMP2 et l’effraction extra-capsulaire étaient des facteurs pronostiques indépendants de la survie liée à la maladie. Nous avons pu classer les patients en 4 niveaux de risque et montré qu’ils avaient des chances équivalentes de réponse à l’immunothérapie. Nos données sont une base pour un essai clinique dirigé par biomarqueur, proposant de la chimiothérapie ou de l’immunothérapie néoadjuvantes, dans le but de diminuer le pourcentage de patients présentant des récidives sévères et précoces
The objective of the thesis was to decipher the molecular state of tumor infiltrating dendritic cell (DC) and their relation to the tumor microenvironment. By combining the analysis of human tumor samples by flow cytometry and RNA sequencing, of tumor secretome and of a large dataset of in vitro DC-Tcell interactions I obtained 2 main findings. First, we reported a novel classification of human activated DC, that are either “secretory” that is specialized in secreting cytokines and chemokines, or “helper” that is specialized at inducing the secretion of a broad range of T helper cytokines after cell co-culture. DC infiltrating inflamed human head and neck cancer matched the “secretory” phenotypic and transcriptomic signatures. Beyond this novel biological concept, this classification is of importance as a theoretical basis for adjuvant-based immunotherapy. Secondly, we showed that tumor inflammation was not the main prognostic factor for oral cavity cancer (OCC) patients, but that MMP2 and the presence of extra-nodal extension were independent predictors of reduced disease-specific survival. We could stratify OCC into 4 prognostic groups and showed that they had similar expected rates of response to immunotherapy. Our data may serve to design a biomarker-driven clinical trial proposing neoadjuvant chemotherapy or immunotherapy to high-risk patients, with the goal of reducing the percentage of OCC patients that will present with early and severe recurrences

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Smigiel, Jacob. "ONCOSTATIN M & TRANSFORMING GROWTH FACTOR SIGNALING CONVERGE TO REGULATE CANCER CELL PLASTICITY." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case152891618991579.

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Nishikawa, Gen. "Bone marrow-derived mesenchymal stem cells promote colorectal cancer progression via CCR5." Kyoto University, 2019. http://hdl.handle.net/2433/244520.

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Pearce, Janina V. "The Role of Tumor and Tumor Microenvironment on Breast Cancer-Associated Adipocyte Plasticity." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/5933.

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Cancer-associated cachexia is a condition defined by a sustained net-negative energy imbalance. Although the different types of adipose tissue – white, beige, and brown – have been implicated in contributing to cancer-associated cachexia, the mechanisms of these maladaptive changes and their impact on whole-body energy expenditure have not been fully elucidated. Using breast cancer as our model, we demonstrate white adipose tissue browning in murine and human breast cancer; furthermore, we demonstrate that this effect is extremely localized and takes place early in tumor progression. We utilized in vitro cell culture techniques and demonstrate that cancer secreted factors and cross-talk with white adipocytes decrease expression of classic white adipose tissue-related genes. We also demonstrate in murine and human culture models that cancer secreted factors reduce white adipocyte lipid droplet size, and cross-talk between cancer cells and adipocytes results in an increase in lipolysis-related gene expression. Interestingly, our results strongly suggest that in mice, neither cancer secreted factors nor cross talk with adipocytes can induce white adipose tissue browning, indicate that this process likely occurs independently of direct cancer interactions with local white adipocytes. We demonstrate that interleukin 6, a cytokine with previous implications in white adipose tissue browning, induces interleukin 6-mediated signaling; however, that signaling alone is not enough to directly induce white adipose tissue browning. We present preliminary data suggesting that immune cell population shifts within the white adipose tissue of mice with breast cancer tumors may be source of white adipose tissue browning. We show that the Virginia Commonwealth University Health System has an identifiable population of patients with cancer with what we hypothesize as maladaptive thermogenic adipose tissue activity, and discuss ongoing experiments aimed at understanding the implications of these changes on whole body energy expenditure in human patients. Lastly, in a case of autoimmune diabetes mellitus in the setting of an extra-adrenal paraganglioma, we demonstrate that the interaction between cancer and whole-body metabolism is multifaceted. Together, these experiments demonstrate that adipose tissue plasticity occurs in breast cancer (and other cancers), and that different drivers for individual changes exist within the tumor microenvironment. We predict that further exploration of the exact mechanisms and translational implications will provide useful information to lead to new therapeutic treatments for patients with cancer-associated cachexia.

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Diwanji, Neha. "Role of Tissue Microenvironment in Recruiting Macrophages During Apoptosis-induced Proliferation." eScholarship@UMMS, 2020. https://escholarship.umassmed.edu/gsbs_diss/1084.

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Apoptosis-induced compensatory proliferation (AiP) is a mechanism that maintains tissue homeostasis after stress-induced cell death. During AiP, apoptotic cells induce proliferation of the neighboring surviving cells to compensate for tissue loss. AiP is important for wound healing and tissue regeneration in several model organisms. Additionally, AiP is an important feature of tumorigenesis and tumor relapse as it contributes to tumor repopulation following radiation or chemotherapy. Using an overgrowth tumor model (“undead tissue”) in Drosophila melanogaster, we determined that the initiator caspase Dronc promotes generation of extracellular Reactive Oxygen Species (ROS), which drive activation of the stress kinase JNK and downstream mitogens to promote AiP. We also observed increased numbers of Drosophila macrophages, termed hemocytes, which are attracted to undead tissue. However, the specific mechanisms by which macrophages are recruited to undead tissue are still unclear. Here, we report that the tissue microenvironment of the overgrown undead tissue directs macrophage recruitment during AiP. We demonstrate that ROS, JNK, and the matrix metalloproteinase Mmp2 are important for recruiting macrophages. Mechanistically, undead tissue-produced ROS and active JNK damage the basement membrane (BM) surrounding the undead tissue, by upregulating the expression and activity of Mmp2. The damaged BM then recruits macrophages to the undead tissue. Taken together, we propose a model in which the ROS-JNK-Mmp2 signaling axis damages the BM of undead tissue, resulting in changes in the tissue microenvironment that recruit macrophages to the area of damage to promote AiP and overgrowth.

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Alahuhta, I. (Ilkka). "The microenvironment is essential for OTSCC progression." Doctoral thesis, Oulun yliopisto, 2016. http://urn.fi/urn:isbn:9789526213583.

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Abstract The tumor microenvironment (TME) is critically important for tumor development. The microenvironment consists of fibroblasts, endothelial and immune cells as well as extracellular matrix (ECM), proteases and various other soluble factors produced by the cells. It is challenging to develop methods that appropriately mimic the human microenvironment, but this effort is essential in order to reliably elucidate the properties of potential anti-tumor drugs. The aim of this study was to create new 3D organotypic invasion models based on human tissue that would be used to study the effects of the anti-angiogenic molecules arresten and endostatin on tongue squamous carcinoma cells. The classic way to study cancer invasion has been to use a collagen invasion model that is created by mixing rat type I collagen, matrix produced by mouse EHS tumor cells and human fibroblasts. Our research group has developed a novel human myoma tissue based invasion model, which is composed of several different cell types and molecules that are normally present in the human TME. We show how this model is suitable for invasion studies, not only for oral cancer, but for other invasive cell lines as well. There are several matrix-derived fragments that have been shown to possess anti-angiogenic activity. Arresten is a 26 kDa fragment that is cleaved from type IV collagen and is known to inhibit angiogenesis, the formation of new capillaries and tumor growth in vivo. However, its effect on the tumor microenvironment in addition to endothelial cells has not been studied. We show that arresten also directly affects oral cancer cells by decreasing their migration and invasion as well as tumor size, invasion and angiogenesis in in vivo mouse xenografts. Another inhibitor of angiogenesis, endostatin, is cleaved from type XVIII collagen. It has been shown to suppress angiogenesis and tumor growth without toxicity or side effects in mouse models. Our studies show that endostatin directly affects tongue squamous carcinoma cells by reducing their invasion and spreading in organotypic 3D assays and mouse tumor models. In summary, arresten and endostatin are anti-angiogenic as well as anti-invasive molecules and therefore potential cancer drugs. They seem to have a direct effect on carcinoma cells making the cells less invasive. The myoma model allows us to study the effects of anti-cancer molecules with a new prospective
Tiivistelmä Syövän mikroympäristö on erittäin tärkeä syövän kehittymisen kannalta. Se koostuu fibroblasteista, endoteeli- ja immuunisoluista, soluväliaineesta, proteaaseista ja monista muista solujen tuottamista liukoisista molekyyleistä. On haastavaa kehittää uusia menetelmiä, jotka jäljittelisivät oikeaa ihmisen syövän mikroympäristöä, mutta se on välttämätöntä uusien syöpälääkkeiden tutkimiseksi. Väitöstutkimuksen tavoitteena oli kehittää kolmiulotteinen ihmisen myoomakudokseen perustuvan invaasiomalli, jonka avulla voisimme tutkia verisuonten kasvua estävien arresten ja endostatin molekyylien vaikutusta kielisyöpäsoluihin. Aiemin syövän invaasiota on tutkittu käyttämällä klassista kollageeni-invaasiomallia, joka tehdään sekoittamalla rotan tyypin I kollageeniä, hiiren sarkoomasolujen tuottamaa matriksia ja ihmisen fibroblasteja. Tutkimuksissamme kehitimme uuden invaasiomallin, joka perustuu ihmisen myoomakudokseen. Tutkimuksessa sen todettiin sisältävän monia erilaisia soluja ja molekyylejä, joita on normaalistikkin syövän mikroympäristössä. Lisäksi osoitimme, että se sopii invaasiotutkimuksiin monille syöpätyypeille. Soluvälitilamatriksista pilkotaan useita erilaisia molekyylejä joilla on osoitettu olevan angiogeneesia hillitseviä ominaisuuksia. Arresten on 26 kDa kokoinen polypeptidi, jota pilkotaan tyypin IV kollageenista. Sen tiedetään vähentävän angiogeneesia – uusien verisuonten muodostumista ja syövän kasvua in vivo. Sen vaikutuksia muihin kuin endoteelisoluihin ei ole kuitenkaan tutkittu. Tutkimuksissamme se vaikutti suoraan kielisyöpäsoluihin vähentäen niiden liikkumista ja invaasiota kolmiulotteisissa organotyyppisisssä malleissa ja hiirimallissa. Toinen tutkimamme angiogeneesin inhibiittori on endostatin, jota pilkotaan tyypin XVIII kollageenista. Sen tiedetään vähentävän angiogeneesia hiirimalleissa ilman toksisia sivuvaikutuksia. Me osoitimme tutkimuksissamme, että se vaikuttaa suoraan kielisyöpäsoluihin vähentäen niiden invaasiota ja leviämistä 3D organotyyppisissä malleissa sekä hiirikokeissa. Koska arresten ja endostatin ovat anti-angiogeenisiä ja anti-invasiivisia molekyylejä, ne ovat täten potentiaalisia syöpälääkkeitä. Ne näyttäisivät vaikuttavan suoraan syöpäsoluihin vähentämällä niiden invaasiota. Myoomainvaasiomalli mahdollistaa syöpää ehkäisevien molekyylien tutkimisen uudella ja todenmukaisemmalla tavalla

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Eduardo, Rodrigo. "Exploring Tumor Macrophage Interaction in Anaplastic Thyroid Cancer." Master's thesis, Universidade Nova de Lisboa. Instituto de Tecnologia Química e Biológica António Xavier, 2019. http://hdl.handle.net/10362/130111.

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"Anaplastic thyroid cancer (ATC) is the most aggressive form of thyroid cancer, with very high mortality rate. Tumor-associated macrophages (TAMs) can represent up to 70% of ATC’s tumor mass, making them an interesting target for novel therapies. In this thesis, the aim was to further understand the crosstalk between ATC and TAMs. To achieve that, cell surface proteomics of two ATC cell lines (C3948 and T235), in mono- or co-culture with THP-1-derived macrophage-like cells, was performed. The protein Spry-4, an inhibitor of the MAPK-ERK pathway, was found to be downregulated in C3948 cells upon co-culture. Spry-4 protein levels were further evaluated by Western blot; only T235 in co-culture showed a trend for downregulation, although without statistical significance.(...)"
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Landry, Benjamin D. "Tumor-stroma interactions differentially alter drug sensitivity based on the origin of stromal cells." eScholarship@UMMS, 2018. https://escholarship.umassmed.edu/gsbs_diss/1011.

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Tumor heterogeneity observed between patients has made it challenging to develop universal or broadly effective cancer therapies. Therefore, an ever-growing movement within cancer research aims to tailor cancer therapies to individual patients or specific tumor subtypes. Tumor stratification is generally dictated by the genomic mutation status of the tumor cells themselves. Importantly, non-genetic influences – such as interactions between tumor cells and other components of the tumor microenvironment – have largely been ignored. Therefore, in an effort to increase treatment predictability and efficacy, we investigated how tumor-stroma interactions contribute to drug sensitivity and drug resistance. I designed a high throughput co-culture screening platform to measure how tumor-stroma interactions alter drug mediated cell death. I identified tumor-stroma interactions that strongly desensitize or sensitize cancer cells to various drug treatments. The directionality of these observed phenotypes was dependent on the stromal cell tissue of origin. Further study revealed that interactions between tumor cells and fibroblasts modulate apoptotic priming in tumor cells to mediate sensitivity to chemotherapeutics. The principles uncovered in this study have important implications on the use of drugs that are designed to enhance apoptosis. For example, based on our screening data, I hypothesized and experimentally validated that the effectiveness of BH3 mimetic compounds would be strongly dependent on the fibroblast growth environment. Taken together, our study highlights the importance of understanding how environmental interactions alter the drug responses of cancer cells and reveals a mechanism by which stromal cells drive broad spectrum changes in tumor cell sensitivities to common chemotherapeutics.

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Rogon-Lamparski, Zbigniew [Verfasser], and Roland [Akademischer Betreuer] Eils. "Reverse engineering of gene regulatory networks governing cell-cell communication in the microenvironment of pancreatic cancer / Zbigniew Rogon-Lamparski ; Betreuer: Roland Eils." Heidelberg : Universitätsbibliothek Heidelberg, 2011. http://d-nb.info/1179230086/34.

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Jacquemin, Guillaume. "L'échec de l'homéostasie intestinale normale sous l'influence de signaux de paracrine dérivés de cellules tumorales." Electronic Thesis or Diss., Paris Sciences et Lettres (ComUE), 2019. https://theses.hal.science/tel-02873486.

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L'homéostasie épithéliale et la tumorigénèse sont deux concepts étroitement liés. En effet, la formation d’une tumeur et son évolution vers le cancer sont la conséquence d’une perte de contrôle des interactions spatiales et mécaniques des cellules épithéliales avec leur environnement. Ces altérations de l’homéostasie peuvent avoir deux origines : une origine intrinsèque, souvent due à des mutations, où la cellule perd sa capacité à interpréter correctement les signaux environnementaux et une origine extrinsèque où l’environnement lui-même ne fournit plus d’informations cohérentes capables d’organiser correctement le tissu.De précédents travaux ont montré des similarités sur le plan transcriptionnel entre certaines cellules souches intestinales tumorales et normales. L’objectif de cette thèse était d'étudier le processus d’initiation tumorale et l'hétérogénéité intratumorale centrée sur les cellules épithéliales dans le cadre du cancer colorectal.Grâce au modèle organoïde, permettant d'étudier in vitro des cellules épithéliales évoluant dans un micro-environnement contrôlé exempt de cellules stromales, nous avons identifié un effet « transformant » des cellules tumorales sur des cellules sauvages. Nos travaux ont montré que cette transformation était médiée par des protéines sécrétées. En utilisant la spectrométrie de masse SILAC, nous avons identifié les protéines exclusivement synthétisées par les organoides tumoraux. Cette analyse nous a permis d'identifier un facteur nécessaire à la transformation observée : la thrombospondine-1 (Thbs1). En effet, la neutralisation de Thbs1 par anticorps ou par ablation génétique dans les organoïdes tumoraux a été suffisante pour abolir l’effet transformant. La transformation des organoïdes sauvages se manifeste par un changement morphologique : une perte de polarisation cellulaire, la formation de kystes vides et une perte de compartimentation des cellules prolifératives normalement limitées à la crypte intestinale. L’analyse du transcriptome des organoïdes sauvages transformés par séquençage d'ARN a révélé une activation de la voie de signalisation Hippo, récemment décrite dans le développement et la régénération de l’épithélium intestinal. Nos travaux ont permis de montrer comment les cellules tumorales sont capables de conduire les cellules saines à adopter un programme génétique de régénération les rendant ainsi aptes à survivre et à proliférer dans un contexte tumoral.Ce travail contribue à une meilleure compréhension du remodelage précoce des tumeurs et de la communication entre les cellules épithéliales indépendamment des cellules stromales. Le mécanisme moléculaire que nous avons mis en évidence appuie l'hypothèse selon laquelle les cellules souches sauvages coexistent avec des cellules mutantes au sein des tumeurs et contribuent à la croissance tumorale
Epithelial homeostasis and tumorigenesis are two intertwined concepts. Indeed, the formation of a tumour and its progression to aggressive stages are the consequence of a loss of control of the spatial and mechanical interactions of epithelial cells with their environment. Such perturbed tissue homeostasis can have two origins: an intrinsic one, often due to genetic mutations, causing mutant cells to lose the ability to correctly interpret environment signals, and an extrinsic or non-cell autonomous cause, as the environment surrounding mutant cells can no longer provides coherent information to correctly orchestrate tissue homeostasis.Previous results in the lab indicated that some tumour cells transcriptionally resemble normal stem cells. I was intrigued by this observation and decided to study the molecular basis of intratumoral heterogeneity, keeping in mind that normal-like stem cells could be present within tumours. My PhD was focused on examining interactions between normal and tumour epithelial cells, using the stroma-free model of organotypic cultures. During these studies, I discovered and characterised a hitherto unknown mechanism of cellular communication between tumour epithelial cells and genetically wild type epithelial cells in the context of colorectal cancer.Taking advantage of the intestinal organoid model system, allowing in vitro study of epithelial cells organising in a defined micro-environmental context free of stromal cells, I identified a rapid "transforming" effect of tumour cells on genetically wild type intestinal stem cells. I then demonstrated that this fast and reversible transformation was mediated by a secreted protein, and evaluated by SILAC mass spectrometry which proteins were specifically secreted by tumour but not normal organoids. This high-throughput quantitative analysis allowed us to identify a factor that was necessary for the observed transformation: thrombospondin-1 (Thbs1). Indeed, inhibition of Thbs1 by neutralizing antibodies or by genetic knock-out was sufficient to abolish the transforming capacity of tumour organoids. Transformation of wild type organoids by tumour organoids is manifested by a morphological change resulting in loss of cell polarisation and formation of hollow cysts, but also by a loss of compartmentalisation of proliferative cells, normally restricted to the crypt regions of organoids. In order to understand how Thbs1 induced such a change, I then analysed the transcriptome of transformed organoids by RNA sequencing and showed a specific activation of the Hippo signalling pathway in response to tumour-derived conditioned medium. This study shows how tumour cells can induce genetically wild type cells to switch to a tumour-like behaviour, using signal such as Hippo pathway activation normally employed during regeneration, making non-mutant cells dangerously adapted to survive and proliferate in a tumoral context.This work provides original mechanistic insights into the processes of early tumour remodelling and epithelial cell communication independently of stromal cells. The molecular mechanisms we have unveiled support the hypothesis that wild type stem cells can co-exist with mutant cells in tumours and contribute to tumour growth and clonal expansion, thanks to paracrine factors (like Thbs1) secreted by surrounding tumour cells, which allow them to thrive in the tumour environment

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Doherty, Mary Rose. "INTERFERON-BETA REGULATES CANCER STEM CELL PLASTICITY TO PROMOTE POSITIVE CLINICAL OUTCOME IN TRIPLE-NEGATIVE BREAST CANCER." Case Western Reserve University School of Graduate Studies / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=case1540926583593107.

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Nelson, Mark Tyler. "Biomimetic Electrospun Fibers for Cancer Cell Migration, Chemotaxis, andAnti-Metastatic Drug Testing." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429031970.

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Ramos, Grasieli de Oliveira. "O microambiente tumoral como fator modificador no processo de invasão e progressão tumoral no carcinoma espinocelular de origem bucal." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/147112.

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INTRODUÇÃO: O carcinoma espinocelular de origem bucal (CEC) apresenta uma alta taxa de mortalidade devido à invasividade das células tumorais. A migração celular, principal evento da invasão e metástase, pode ser regulada tanto por fatores intrínsecos, como adesão e contratilidade celular, quanto extrínsecos, como composição, densidade e remodelagem da matriz extracelular (MEC). OBJETIVO: Avaliar o papel de elementos intrínsecos e extrínsecos sobre o processo invasivo do carcinoma espinocelular de origem bucal. MÉTODOS: Foi realizada imuno-histoquímica para as proteínas: Miosina II (isoformas A, B e C), metaloproteinases de matriz (1, 2, 9 e 14); imunofluorescência as proteínas: e-caderina, n-caderina, FAK, paxilina, vinculina e fibronectina em amostras de CEC oral. Foi realizado ensaio de migração nas seguintes condições: 1 – matriz 2D com o substrato de fibronectina, ou laminina ou matrigel; 2 – matriz 3D com colágeno na presença ou não de fibronectina ou laminina; 3 – matriz 3D com diferentes concentrações de colágeno (0,6; 1,2 e 1,8 mg/ml) + fibronectina na presença ou não de um inibidor de MMP. Foi realizado análise de adesão celular utilizando-se o microscópio TIRF e o microscópio confocal, tanto em matrizes 2D quanto 3D. Foram realizados esferoides celulares para avaliar a contratilidade celular, através do plaqueamento das células em gel de agarose e a utilização de drogas que inibem ou que induzem a contratilidade, bem como a partir de células transfectadas com versões fosfomiméticas para a cadeia leve de miosina. Foi realizado ainda western blotting para proteínas: e-caderina, FAK, vinculina, paxilina, N-caderina, integrinas e as isoformas de miosina II, bem como foi avaliado os níveis de ativação das proteínas da família RhoGTPase, as quais estão envolvidas no controle da migração celular. RESULTADOS: A expressão das MMPs analisadas e das isoformas de miosinas foi maior nas zonas de invasão tumoral, sendo que o CEC oral também apresenta uma maior expressão de proteínas associadas à adesão com a MEC. A migração celular foi afetada pela densidade e a composição da MEC, bem como pela atividade das MMPs. Adicionalmente, a modulação das proteínas de adesão célula-matriz altera a velocidade de migração, a direcionalidade dessa migração e também a forma de migração, mudando de uma migração coletiva para uma migração individual. O aumento na contratilidade células resulta numa dispersão celular enquanto que a diminuição da contratilidade resulta numa melhor adesão célula – célula. CONCLUSÕES: O comportamento das células tumorais pode ser modulado através de fatores extrínsecos como, por exemplo, a alteração no microambiente tumoral, seja ela por mudança no substrato ou na densidade da matriz, e também dos fatores intrínsecos como a alteração nos níveis de miosina.
INTRODUCTION: Oral squamous cell carcinoma (OSCC) presents high mortality index due to the invasive phenotype of tumor cells. Cell migration is the main event in cell invasion and metastasis and it can be regulated by intrinsic factor, such as adhesion and cell contractility, and extrinsic factors, such as density and extracellular matrix (EMC) remodeling. OBJECTIVE: Analyze the role of intrinsic and extrinsic factor during the invasive process of oral squamous cell carcinoma. METHODS: We performed immunostaining in OSCC samples for the following proteins: myosin II (isoforms A, B and C), matrix metalloproteinase (1, 2, 9 and 14) e-cadherin, n-cadherin, FAK, paxillin, vinculin and fibronectin. We also performed migration assays with OSCC cell line in the following conditions 1 – 2D matrix with fibronectin or laminin or matrigel; 2 – 3D matrix with collagen in the presence or not of fibronectin or laminin; 3 – 3D matrix with different collagen concentration (0,6; 1,2 e 1,8 mg/ml) with fibronectin in the presence or not of the MMP inhibitor. In order to analyze cell adhesion, it was performed Total Internal Reflectance Fluorescence and Confocal microscopy, in 2D and 3D matrix. To analyze cell contractility, cells were plated in agarose gel in order to produce spheroids, which were treated with drugs that inhibit or induce cell contractility or cells were previously transfected with Myosin Light Chain phosphomimetics mutants. It was also performed western blotting to: e-cadherin, n-cadherin, FAK, paxillin, vinculin and myosin II isoforms, as well as it was analyze the levels in RhoGTPase family, which are involved in cell migration control. RESULTS: The expression to MMPs and myosin II isoforms were higher at invasion zone of the tumor, and the OSCC presented higher expression of proteins associated to adhesion to ECM. Cell migration was affected by the EMC composition and density and by MMP activity. Also, the modulation of cell-matrix adhesion proteins altered migration speed, cell directionality as well as influenced the switch between collective and single cell migration. The increase in cell contractility resulted in cell dispersion while the decrease in cell contractility resulted in a better cell-cell adhesion. CONCLUSIONS: The behavior of cell tumor can be modulate by extrinsic factors, for example, the change in tumor microenvironment, by the change in the EMC substrate or density and by intrinsic factors such as the alteration in myosin levels.

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Diaz, Herrero Alba. "Characterization of Tumor Immune Microenvironment in Human Diffuse Large B-cell Lymphoma." Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASL057.

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Le lymphome diffus à grandes cellules B (DLBCL) est le sous-type le plus fréquent de lymphome non hodgkinien (NHL), caractérisé par une prolifération anormale de cellules B matures. C'est une maladie agressive pour laquelle les stratégies thérapeutiques actuelles sont insuffisantes. Le microenvironnement tumoral (TME) est un réseau dynamique de cellules, molécules et des autres éléments qui entourent une tumeur. Ceux-ci tiennent un rôle prépondérant dans le développement du cancer, la réponse au traitement et la survie des patients. Étudier le TME chez les patients atteints de DLBCL est essentiel pour découvrir de nouveaux mécanismes cellulaires et moléculaire impliqués dans progression de la maladie et identifier des biomarqueurs pronostiques. Cependant, sa structure tissulaire diffuse rend difficile l'étude précise de l'organisation et des interactions cellulaires au sein du TME.L'objectif de ce projet de thèse est de réaliser une caractérisation multimodale complète des cellules immunitaires dans le microenvironnement tumoral du DLBCL. Pour faciliter l'accès aux échantillons humains, j'ai développé et mis en place un protocole de recherche clinique permettant un accès à des biopsies de patients suivis à l'hôpital Saint-Louis, et garantissant que la cohorte de patients reflète l'hétérogénéité de la maladie.Tout d'abord, j'ai réalisé une caractérisation en profondeur des lymphocytes T infiltrant la tumeur (TILS). Pour ce faire, j'ai utilisé des technologies innovantes de cytométrie en flux et spectrale multiparamétrique pour étudier finement la diversité de cellules T dans les biopsies de DLBCL ainsi que leurs réseaus de communication avec les autres cellules immunitaires. Une analyse non supervisée a pu mettre en évidence la présence de nouveaux sous-types de cellules T, par comparaison aux tissus contrôle. De plus, l'analyse de l'expression ligand-récepteur a permis d'étudier la communication cellulaire de ces sous-populations de cellules T dans le TME.En parallèle de cette étude, j'ai pu caractériser les profils transcriptomiques des cellules immunitaires présents dans le TME. Pour ce faire, j'ai utilisé une technologie de pointe, la transcriptomique spatiale, des outils bio-informatiques innovant pour cartographier l'expression des gènes directement dans des échantillons de biopsies de DLBCL fixés au formol et inclus en paraffine. J'ai ainsi pu identifier des profils d'expression génique distincts et anatomiquement restreints, défiant la notion historique d'une architecture diffuse du TME du DLBCL. Ces profils peuvent être classifiés en écosystèmes, différant de par leurs compositions cellulaires, leurs fonctions et leurs interactions avec les cellules avoisinantes. De façon importante, la prédominance de certains écosystèmes permettent une classification des patients selon leur taux de survie globale, révélant le potentiel pronostique de ces identités cellulaires spatiales.Enfin, j'ai réalisé une évaluation in vitro du mécanisme d'action et de l'efficacité d'un anticorps bloquant développé par la société pharmaceutique Servier. Celui-ci a été développé pour qui perturber un signal inhibiteur entre les cellules NK et les cellules B malignes. Mes résultats montrent que le candidat améliore la cytotoxicité des cellules NK à l'encontre des cellules tumorales dans un système de co-culture in vitro. Ces résultats soulignent l'importance de cibler les interactions cellulaires entre les cellules immunitaires et les cellules B malignes pour le développement de thérapies plus efficaces dans le DLBCL.Ce projet multidisciplinaire, mené sur des échantillons humains, apporte une compréhension approfondie de l'hétérogénéité des cellules immunitaires, de leurs interactions et localisations dans le microenvironnement du DLBCL. Ainsi, ce projet pourrait conduire à la découverte de nouveaux biomarqueurs et de stratégies thérapeutiques plus efficaces pour les patients atteints de DLBCL
Diffuse Large B-cell Lymphoma (DLBCL) is the most prevalent subtype of non-Hodgkin's Lymphoma worldwide, characterized by an abnormal proliferation of mature B cells. It is an aggressive B-cell malignancy for which the current therapeutic strategies are still insufficient. The tumor microenvironment (TME) is the dynamic network of cells and all elements surrounding and interacting with the tumor. It plays an important role in cancer development, treatment response, and patient survival. Consequently, investigating the TME in DLBCL patients is crucial to discover the mechanisms leading to relapse and identify prognostic biomarkers. However, its diffuse tissue structure presents a challenge in elucidating the cellular organization and communication within the TME. The objective of my Ph.D. thesis is to conduct a comprehensive multimodal characterization of the immune cells within the DLBCL tumor microenvironment.To facilitate access to human samples, I developed and implemented an ethically approved clinical research protocol and a circuit of tissue and blood samples from patients with DLBCL treated at Saint Louis hospital, ensuring that the patient cohort reflects the heterogeneity of the disease.First, I performed a deep characterization of T lymphocytes, with special focus on describing their role within the DLBCL tissue. Indeed, Tumor-infiltrating T-cells (TILS) are key players in the NHL TME, presenting different subtypes and cell states. I apply multiparametric flow cytometry and high-dimensional spectral cytometry to investigate the complex landscape of T diversity in DLBCL biopsies, as well as their communication patterns with other immune cells in the tissue. The unsupervised analysis approach identified unexpected T-cell subtypes at a protein level, compared to tissue control and other lymphoproliferative disorders. Furthermore, the ligand-receptor expression analysis enabled the cell-cell communication study of those T-cell subpopulations within the TME context. Second, I aimed to characterize transcriptomic immune landscapes at a large scale within DLBCL tissue. However, RNA sequencing technologies characterize isolated cells from dissociated tissues with a loss of spatial context. I applied spatial transcriptomics, a cutting-edge technology that enables gene expression mapping in formalin-fixed paraffin-embedded samples of DLBCL biopsies, thus preserving their morphological information. I identified distinct anatomically restricted gene expression profiles in DLBCL samples, defying the historical notion of DLBCL diffuse architecture. These profiles can be classified into ecosystems that differ in cellular composition, functional patterns, and neighborhood characteristics. Moreover, their spatially resolved signatures classify patients with different overall survival revealing the prognostic potential of these spatial identities.Third, I evaluated the effects of altering the communication between NK cells and malignant B cells in DLBCL. I performed a functional in vitro assessment of a blocking antibody developed by the pharmaceutical company Servier. The functional assays demonstrated the effect of the molecular candidate in co-culture settings by improving cytotoxic functions of NK cells against tumor cells. These findings highlight the importance of targeting the interaction between effector cells and malignant B cells to develop effective therapies for DLBCL.This multidisciplinary project carried out on human samples provides a deep understanding of the heterogeneity of immune cells in DLBCL microenvironment at a protein and transcriptomic level while considering their spatial organization. Hence, this project holds significant therapeutic potential, by gaining insights into the disease heterogeneity and its impact on clinical outcome. This project could eventually lead to the discovery of new potential biomarkers and effective therapeutic strategies for DLBCL patients

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Bischof, Ashley Gibbs. "Extracellular Matrix as a Key Mediator of Mammary Tumor Cell Normalization." Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:10780.

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Some epithelial cancers can be induced to revert to quiescent differentiated tissues when combined with embryonic mesenchyme; however, the mechanism of this induction is unknown. This dissertation is based on the hypothesis that because extracellular matrix (ECM) plays a critical role during organ development in the embryo, it also may mediate the differentiation-inducing effects of embryonic mesenchyme on cancer cells. To test this hypothesis, I first optimized methods to isolate ECMs from whole tissues or cultured cells, and to repopulate them with cultured cells, using embryonic tooth as a model system. In Chapter 2, I describe these studies and use them to demonstrate that embryonic ECM is sufficient to regulate odontogenic signaling, cell fate decisions and histodifferentiation during normal tooth development. In Chapter 3, I adapt these methods to show that culture of breast cancer cells with ECM derived from embryonic mammary mesenchyme decreases tumor cell proliferation, and stimulates differentiation, including formation of hollow acini and ducts as well as enhanced expression of estrogen receptor-alpha and decreased migration. Further, when the inductive ECMs were injected into fast-growing breast tumors in mice, they significantly inhibited cancer expansion. Critically, the differentiation observed with ECM was the same as that observed in co-culture with mammary mesenchyme cells, showing that ECM is playing a dominant role in tumor cell normalization. In Chapter 4, I then set out to determine the mechanism by which embryonic ECM normalizes tumor cells, I analyzed the contributions of bound cytokines, ECM composition and mechanics. Western blot analysis revealed several bound growth factors, which remained following decellularization; however, removal of these growth factors using high salt washes had no effect on ECM-mediated normalization of tumors. Further, using proteomics analysis I identified eleven ECM proteins present only within inductive ECMs and by testing these proteins in 3D culture, I found three proteins -- collagen III, biglycan and SPARC -- that increased lumen formation to a similar extent as embryonic ECM. These data confirm that mesenchyme-induced tumor cell normalization is mediated by the insoluble ECM, and reveal the identity of some of the inductive molecules responsible for these effects.

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Tulkki, Valtteri Heikki Juhani. "Oncostatin M receptor overexpression promotes tumour progression in squamous cell carcinoma, via hypoxia signalling and multiple effects on the tumour microenvironment." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/275416.

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Cervical cancer still represents the fourth most common cause of cancer deaths in women worldwide. Human papilloma virus (HPV) infection plays a role in cervical carcinoma initiation, but other genomic changes are needed for pre-malignant abnormalities to fully develop to cancer. This often happens through genomic instability caused by the virus oncoproteins. Several integrative genomic analysis studies have found that one of the most common imbalances in cervical squamous cell carcinoma (SCC) is copy number gain and amplification of chromosome 5p. In this region, copy number gain of the OSMR gene was found to correlate significantly with adverse outcome independent of the tumour stage (p=0.046). Furthermore, this copy number gain correlated with Oncostatin M receptor (OSMR) overexpression and sensitised these cells to Oncostatin M (OSM) leading to increased Signal transducer and activator of transcription 3 (STAT3) phosphorylation, cell migration, invasion and proangiogenic signalling. The aim of this PhD project was to study the role of OSMR overexpression in the SCC tumour microenvironment (TME) and tumour growth in vivo and to study the role of hypoxia inducible factor driven hypoxia signalling in OSMR overexpressing SCC cells and their tumour microenvironment. OSMR overexpression was found to sensitise tumour cells to induce Hypoxia inducible factor 1a and 2a (HIF1a, HIF2a) signalling in normoxic conditions, to promote pro-angiogenic signalling. Furthermore, hypoxic conditions were found to enhance OSM signalling in OSMR overexpressing cells leading to increased expression of markers of epithelial to mesenchymal transition, angiogenesis and migration. In the SCC tumour microenvironment, OSMR overexpression was found to sensitise tumour cells to OSM secreted from macrophages and other immune cells leading to improved tumour growth, angiogenesis and STAT3 activation at the tumour site. Removal of OSMR from either tumour cells or tumour microenvironment led to reduced tumour growth and angiogenesis, along with increased tumour necrosis. I conclude that OSMR overexpression is an important driver of SCC tumour progression and malignancy via STAT3- and HIF-driven signalling and removal of it from either tumour cells or tumour microenvironment drastically hampers tumour growth in vivo. Based on the results of this study, OSMR blockade is a potential novel therapeutic option in advanced SCC.

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Kamboj, Sahil. "Outils avancés pour la modulation du trafic des intégrines dans le cancer de l'ovaire." Electronic Thesis or Diss., CY Cergy Paris Université, 2024. http://www.theses.fr/2024CYUN1300.

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Les intégrines sont des récepteurs hétérodimériques de surface cellulaire qui jouent un rôle essentiel dans la gestion des interactions cellule-cellule, lesquelles influencent ensuite des processus biologiques à plusieurs échelles tels que le comportement cellulaire, le remodelage de la matrice extracellulaire et la formation des tissus. Ces processus s'étendent de quelques millisecondes à plusieurs jours. Les méthodologies existantes pour étudier la fonction des intégrines à différentes échelles biologiques - des cellules individuelles aux tissus entiers - s'avèrent souvent chroniques et manquent de capacité pour cibler des interactions cellule-cellule spécifiques de manière aiguë.Pour remédier à cette limitation, nous avons conçu des cellules qui modifient rapidement leur comportement en régulant à la baisse la population de surface des intégrines α5β1 par le biais d'un processus d'endocytose médiée par la clathrine à chaud. Cette méthode innovante permet d'induire une internalisation spécifique des intégrines α5β1 et d'obtenir une régulation négative aiguë dans diverses lignées cellulaires en l'espace de 5 à 30 minutes. Nos résultats démontrent que cette internalisation induite des intégrines α5β1 entraîne une diminution de la surface cellulaire, favorise l'absorption de la fibronectine extracellulaire et réduit le taux de compaction des sphéroïdes tumoraux.Ce contrôle ciblé de processus à plusieurs échelles par la régulation négative rapide des intégrines α5β1 met en évidence l'utilité de l'endocytose à chaud en tant qu'outil puissant pour moduler de manière aiguë la biologie cellulaire. Notre approche offre une vitesse sans précédent dans l'ajustement du microenvironnement cellulaire, présentant de nouvelles avenues thérapeutiques et des stratégies innovantes pour l'ingénierie tissulaire en ciblant rapidement les interactions cellule-microenvironnement
Integrins are heterodimeric cell surface receptors that play a critical role in governing cell-cell interactions, which subsequently influence multiscale biological processes such as cell behaviour, extracellular matrix remodeling, and tissue formation. These processes span from milliseconds to several days. Existing methodologies to study integrin function across different biological scales—from single cells to whole tissues—often prove to be chronic and lack the capability to target specific cell-cell interactions acutely.To address this limitation, we engineered cells to rapidly alter their behavior by downregulating the surface population of α5β1 integrins through a process of hot-wired clathrin-mediated endocytosis. This innovative method enables inducible, specific internalization of α5β1 integrins, achieving acute downregulation across various cell lines within 5-30 minutes. Our findings demonstrate that this induced internalization of α5β1 integrins results in a decrease in cell area, promotes the uptake of extracellular fibronectin, and reduces the rate of tumor spheroid compaction.This targeted control of multiscale processes through the rapid downregulation of α5β1 integrins highlights the utility of hot-wired endocytosis as a potent tool for acutely modulating cell biology. Our approach offers unprecedented speed in tuning the cellular microenvironment, presenting novel therapeutic avenues and innovative strategies for tissue engineering by quickly targeting cell-microenvironment interactions

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McKenna, Mary Kathryn. "NOVEL ROLE OF PROSTATE APOPTOSIS RESPONSE-4 TUMOR SUPPRESSOR IN B-CELL CHRONIC LYMPHOCYTIC LEUKEMIA." UKnowledge, 2017. https://uknowledge.uky.edu/microbio_etds/17.

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Chronic Lymphocytic Leukemia (CLL) is defined by the accumulation of clonally expanded CD5+ and CD19+ B lymphocytes in blood and secondary lymphoid organs with impaired apoptotic mechanisms. CLL represents one third of all leukemia cases with an average age of 72 years at diagnosis making it the most common adult leukemia. The Eµ-Tcl1 mouse serves as an excellent model to study the development of CLL as they progress to a CLL like disease by 9-14 months of age, due to overexpression of an oncogene, T cell Leukemia 1(Tcl1), specifically in B cells through the Ig VH promoter and Eµ enhancer (Bichi et al. PNAS. 2002). In an adoptive transfer model, intravenous or intraperitoneal injection of primary CD5+CD19+ CLL cells from the Eµ-Tcl1 CLL mouse into recipient syngeneic mice leads to the development of a CLL like disease within 3-8 weeks of transfer. We have characterized the growth of CLL cells in these mice by periodic submandibular bleeding, spleen ultrasonography and flow cytometry. We find that Eµ-Tcl1 CLL cells express more Prostate apoptosis response-4 protein (Par-4), a known pro-apoptotic tumor suppressor protein, than normal B-1 or B-2 cells in mice. Par-4 is silenced by promoter methylation in more than 30% of all cancers and has been shown to be secreted and to induce apoptosis selectively in various types of cancer cells but not in normal cells. We found that CLL cells have constitutively active B-cell receptor signaling (BCR) and that inhibition of BCR signaling with FDA approved drugs causes a decrease in Par-4 protein, mRNA levels, and an increase in apoptosis. In particular, activities of Src family kinases, spleen tyrosine kinase and Bruton’s tyrosine kinase are required for Par-4 expression in CLL cells, suggesting a novel regulation of Par-4 through BCR signaling in both Eµ-Tcl1 CLL cells and primary human CLL samples. Consistent with this, lenti-viral shRNA mediated knockdown of Lyn kinase leads to a decrease in Par-4 expression in MEC-1 cells, a human CLL derived cell line. Igα (CD79a) silencing in primary human CLL cells also results in down regulation of Par-4 expression. Additionally, we knocked down expression of Par-4 in MEC-1 cells which resulted in a decrease in cell growth that could be attributed to an increase in p21 expression and a reduction in the G1/S cell cycle transition. We have also observed this phenomenon by crossing mice deficient in Par-4 with the Eµ-Tcl1 mouse where lack of Par-4 delays CLL growth in the mouse significantly (time to euthanization due to poor body condition - Eµ-Tcl1: 8.9mo vs Par4-/-EµTcl1: 11.97 mo, p = 0.0472) and splenic B-CLL cells from these mice also have increased expression of p21. Since mice in this cohort are whole body knockout for Par-4, the difference in survival times between the Par-4 +ve and Par-4 –ve EµTcl1 mice could be due to the influence of Par-4 on CLL cells as well as the effect of Par-4 secreted by the CLL cells on the microenvironment. There could be other potential roles for Par-4 in the context of CLL which are under further investigation. We have also investigated the site of CLL growth in mouse models to determine that the spleen is the primary organ to accumulate the CLL tumor burden. We have found that splenectomy significantly delays the development of CLL in the primary Eμ-Tcl1 mouse model and prevents growth and development in the adoptive transfer model. Interestingly, splenectomy did not delay CLL development as significantly in animals deficient for Par-4 compared to C57BL/6 wild type mice. Par-4 appears to regulate a specific microenvironment required for CLL growth. Current studies are investigating the role of Par-4 in the microenvironment and the cell types that are critical for CLL growth within the splenic niche.

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Kashtl, Ghasaq J. "Differential membrane-type matrix metalloproteinase expression in phenotypically defined breast cancer cell lines: Comparison of MT-MMP expression in environmentally-challenged 2D monolayer cultures and 3D multicellular tumour spheroids." Thesis, University of Bradford, 2018. http://hdl.handle.net/10454/17346.

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Matrix metalloproteinases (MMPs) are a family of zinc endopeptidases capable of digesting the extracellular matrix (ECM), which is essential for tissue structure and transmitting messages between cells. MMPs play an important role in cancer, controlling cell migration, proliferation, apoptosis, regulation of tumour expansion, angiogenesis and invasion. Previous research has indicated high expression of MT1-MMP in breast cancers suggesting a potential role in tumour progression. Our results confirm that 3D multicellular tumour spheroids (MCTS) using phenotype-specific breast cancer cell lines are a valuable experimental model of the tumour microenvironment. Optimisation of MCTS culture growth conditions using different breast cancer cell lines (MCF-7, T47D, MDA-MB-468 and MDA-MB-231) was performed. Unexpected detection of MT1-MMP in MCF-7 MCTS warranted further investigation. MT1-MMP expression in different micro-environmental conditions, including hypoxia and nutrient deprivation (serum-free induced autophagy) were measured in MCF-7 monolayer cultures and MCTS models using immunofluorescence (IF), immunohistochemistry (IHC) and western blot (WB). MT1-MMP expression was rapidly and irreversibly up-regulated in MCF-7 breast cancer cells under conditions of stress (hypoxia and autophagy) compared to normal conditions suggesting an important role of the culture environment on cells behaviour and protein expression. We employed isobaric tags for relative and absolute quantitation (iTRAQ) technology to correlate MT1-MMP increase with proteomic profiles in MCF-7 breast cancer cell grown under hypoxic, serum-free and 3D MCTS conditions. More than 3500 proteins were identified, which were clustered into groups based on response to unique or shared microenvironment changes. Hypoxic monolayer and spheroid cells exhibited changes in anaerobic metabolism and lipid synthesis, respectively, whereas autophagy resulted in up-regulation of cellular component disassembly. The result indicated multiple drivers of MT1-MMP expression in MCF-7 cells.
Al-Mstansiriya University, Iraq

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Ferreira, Luís Pedro Correia Pinto. "Development of multicelular 3D cancer testing platforms for evaluation of new anti-cancer therapies." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22713.

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Mestrado em Bioquímica Clínica
O cancro do pulmão (CP) é um dos cancros mais diagnosticados a nível mundial e também um dos mais mortíferos. Atualmente, as terapias administradas a nível clínico para o tratamento do CP são ainda extremamente ineficazes e limitadas no que diz respeito ao aumento da taxa de sobrevivência dos pacientes oncológicos. Esta realidade demonstra a necessidade de investigar ativamente novas terapias para o tratamento desta neoplasia. No entanto a validação pré-clínica de terapias inovadoras para o CP tem-se revelado extremamente difícil devido à inexistência de plataformas que sejam adequadas para testes a nível laboratorial, uma vez que as culturas celulares in vitro bidimensionais (2D), recomendadas pelas agências regulatórias são incapazes de mimetizar as caraterísticas principais dos tumores humanos. Estas limitações têm originado uma fraca correlação entre a performance das terapias nos estudos in vitro e a obtida em ensaios clínicos controlados. Neste contexto, os modelos de tumores tridimensionais (3D) in vitro têm vindo a ser reconhecidos como uma solução para este problema, pois podem recapitular várias componentes do microambiente tumoral. Das várias plataformas 3D in vitro de CP investigadas atualmente muito poucas avaliaram o papel da inclusão de células estaminais mesenquimais (MSCs). Para colmatar esta lacuna, o trabalho de investigação desenvolvido no âmbito desta dissertação descreve a produção e otimização de novos modelos hétero-celulares 3D in vitro. Estas plataformas são compostas por células tumorais do CP (A549) e do seu estroma, nomeadamente fibroblastos da pele e células estaminais mesenquimais derivadas da medula óssea (BM-MSCs). Estes três tipos de células foram co-cultivadas em micropartículas poliméricas de policaprolactona revestidas por ácido hialurónico, com o objetivo de incluir este componente da matriz extracelular que se encontra presente no microambiente do CP. Esta abordagem permitiu formar a nível laboratorial microtecidos multicelulares 3D híbridos que melhor mimetizam a heterogeneidade celular das neoplasias pulmonares. Os resultados obtidos demonstraram que os microtumores formados através da técnica de sobreposição-líquida são reprodutíveis em termos de morfologia e tamanho, apresentaram núcleos necróticos, organização celular 3D e produziram proteínas do microambiente tumoral. Além destas caraterísticas, os dados obtidos através de microscopia de fluorescência revelaram que as BM-MSCs migram para o interior dos microtumores ao longo do tempo. A avaliação da citotoxicidade da Doxorubicina, um fármaco anti-tumoral rotineiramente utilizado a nível clínico, demonstrou que a inclusão de micropartículas aumenta a resistência das células tumorais em modelos homotípicos. Nos modelos tri-cultura heterotípicos a citotoxicidade foi comparável à obtida em microtumores sem micropartículas. Estes resultados evidenciam assim o papel importante dos fibroblastos e das BM-MSCs na resposta dos microtumores. Numa visão global, os modelos 3D formados recapitulam com mais exatidão o microambiente do cancro do pulmão e poderão servir no futuro como plataformas de teste para descobrir ou aperfeiçoar novas terapias, ou combinações de terapêuticas, para este tipo de neoplasia.
Lung cancer (LC) is one the most commonly diagnosed cancers worldwide, being also one of the deadliest. Currently, clinically administered therapies for treatment of LC are still extremely ineffective and limited in increasing oncologic patients survival rates. This reality evidences the necessity of actively investigating novel therapies for the treatment of LC. However, preclinical validation of novel therapies as revealed itself as an extremely arduous process, due to the lack of suitable laboratory testing platforms since the recommend in vitro bi-dimensional (2D) cell cultures are unable to fully mimic the main hallmarks of human tumors. In this context, in vitro tridimensional (3D) tumor models are being increasingly recognized as a solution due to their ability to correctly recapitulate several characteristics of the tumor microenvironment (TME). Amongst currently developed 3D in vitro platforms for the study of LC, few have included or studied the role of mesenchymal stem cells (MSCs). To provide further insights into this hypothesis, the research work developed in this thesis describes the production and optimization of novel heterotypic in vitro 3D models, comprised by non-small-cell lung cancer cells (A549) and stromal cells, namely skin fibroblasts (HFs), and bone-marrow derived mesenchymal stem cells (BM-MSCs). These three diverse cell populations were co-cultured in hyaluronic acid coated polymeric polycaprolactone microparticles (LbL-MPs) as to include this key extracellular matrix component of LC TME. This approach allowed the formation of 3D multicellular heterotypic microtissues (3D-MCTS) that better recapitulate the cellular heterogeneity of LC TME in the laboratory. The obtained findings demonstrate that these models formed via the liquid-overlay technique were reproducible in terms of morphology and size, presented necrotic core formation, 3D cellular organization, and deposited matrix proteins in a similar manner as in the TME. Besides this, fluorescence microscopy data revealed that BM-MSCs migrated overtime into the microtumors core . Performed doxorubicin in vitro cytotoxicity assays revealed that the inclusion of LbL-MPs lead to an increased resistance of homotypic A549 monoculture models against this anti-cancer drug commonly used in clinical treatments. Alongside, the cytotoxicity obtained in triculture heterotypic models was comparable to that of microtumors without LbL-MPs inclusion, showcasing the role of HFs and BM-MSCs in microtumors response to therapy. Globally, the herein bioengineered 3D models were able to recapitulate with an increased precision the TME of LC, making them suitable test platforms for development or improvement of standalone or combinatorial therapies for this type of neoplasia.

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Ma, Yuting. "The crosstalk between dying tumor cells and immune effectors within tumor microenvironment elicited by anti-cancer therapies dictates the therapeutic outcome." Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00636891.

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Besides exerting cytostatic or cytotoxic effects on tumor cells, some anti-cancer therapies (anthracyclines, oxaliplatin, X-Rays) could trigger an immunogenic cell death modality, releasing danger signals to alert immune system. We have shown that tumor-specific IFN- producing CD8+ T cells (Tc1) are mandatory for the success of chemotherapy to prevent tumor outgrowth. Priming of Tc1 response depends on IL-1β secretion by DC confronted with anthracycline-treated tumor cells releasing ATP. To identify the inflammatory components which link innate and cognate immune responses, we analyzed the influence of immunogenic chemotherapy on tumor microenvironment. We found an upregulated Th1- and Th17-related gene expression pattern in growth-retarded tumor after anthracycline treatment. By interfering with IFN- or IL-17A pathways, therapeutic effect of doxorubicin and oxaliplatin was abolished and dying tumor cell-based vaccine lost its efficacy to protect mice from live tumor cell rechallenge. Interestingly, we discovered that distinct subsets of  T lymphocytes (V4+ and V6+) colonized tumors shortly after chemotherapy, where they proliferated and became the dominant IL-17 producers within tumor beds. In three tumor models treated with chemotherapy or radiotherapy, a strong correlation between the presence of IL-17-producing  T ( T17) and IFN--producing CD8+ TIL (Tc1) was discovered. IL-17A signaling acts as upstream of IFN- since defect in IL-17RA led to complete loss of antigen specific Tc1 priming. The contribution of  T17 cells (V4+ and V6+) to chemotherapy is critical as V4/6-/- mice showed reduced sensitivity to chemotherapy and vaccination. Also, tumor infiltrating  T17 and Tc1 cells were reduced to basal level in this strain. IL-1β/IL-1R, but not IL-23/IL-23R, is pivotal for IL-17 production by  T cells and the success of chemotherapy. Importantly, adoptive transfer of  T cells could restore the efficacy of chemotherapy in IL-17A-/- mice and ameliorate the effect of chemotherapy in wild type host, provided that they retain the expression of IL-1R and IL-17A. Our research suggest a DC (IL-1β) →  T cells (IL-17) → Tc1 (IFN-) immune axis triggered by chemotherapy-induced dying tumor cells, which is critical for the favorable therapeutic response. To boost the immune system, we try to combine immunogenic chemotherapy with tumor vaccine in the presence of TLR3 agonist Poly (A:U). This sequential combined therapy, which we named VCT, could significantly retard tumor growth or even completely eradicate tumor and establish long-term protection against rechallenge in highly tumorigenic models. To dissect the effect of Poly (A:U) on immune system and that on TLR3 expressing-tumor cells, we performed VCT treatment in nude mice, TRIF-/- mice and with TRIF-silencing tumors. Interestingly, our results suggested that anti-tumor effect of VCT required T cells and intact TRIF signaling pathway at the level of the host and that of tumor cells. Poly (A:U) treatment could induce high level of CCL5 and CXCL10 production from tumor cells both in vitro and in vivo, which could negatively and positively influence the therapeutic outcome. By uncoupling the effect of CCL5 from that of CXCL10, the VCT treatment can be ameliorated. Our study emphasizes that both tumor and host derived inflammatory factors participate in regulating anti-tumor response. We also highlight that therapeutic application of TLR agonists can be optimized through regulating the profile of chemokines and their downstream signaling events.

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Liu, Huayang. "Cell Proliferation Control: from Intrinsic Transcriptional Programs to Extrinsic Stromal Networks." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1430953475.

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Seshadri, Dhruv Ramakrishna. "Immuno-nanotherapeutics to Inhibit Macrophage Polarization for Non-Small-Cell Lung Cancers." Case Western Reserve University School of Graduate Studies / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=case151084330337552.

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36

Adams, Rosie Louise. "The development of a novel 3D migration assay to study the effects of cell signalling and microenvironment on the migratory behaviour of colorectal cancer." Thesis, Durham University, 2015. http://etheses.dur.ac.uk/10962/.

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Colorectal cancer is one of the mostly commonly diagnosed cancers for both men and women in the UK, with a poor survival rate compared to other Western countries and other commonly diagnosed cancer types. Part of the reason for poor prognosis for patients is the diagnosis of the disease at an advanced stage of progression, which has been shown to have a severe impact on patient survival rates. Due to this, the signalling events surrounding the adoption of an invasive phenotype may provide the opportunity to develop therapies to limit the spread of tumours from their original site and improve patient prognosis. It has previously been highlighted that the culture of cells in standard two-dimensional (2D) induces alterations to gene expression via the imposition of a microenvironment which does not reflect the microenvironment experienced by cancer cells in vivo. This limits the accuracy of data obtained using 2D migration assays and can help to account for the failure of some anti-migratory compounds to be effective in in vivo or clinical screening, after showing promise in conventional cell culture tests. This project has aimed to develop a novel three-dimensional (3D) migration assay based on Alvetex® technology, which provides a more biologically relevant microenvironment in vitro, to investigate the role of cell signalling and microenvironment in determining the migratory behaviour of colorectal cancer cells. Through extensive optimisation, the 3D culture of two colorectal cancer cell lines, SW480 and SW620, was established to allow for the assessment of cell migration via histological processing, in addition to the assessment of other behavioural traits via the use of commercial biochemical assays. Modulation of both the Wnt and Insulin-like Growth Factor (IGF)-I signalling pathways via small molecule inhibitors and exogenous protein application has highlighted compounds which alter the migratory behaviour of the colorectal cancer cell lines, results which were not reflected in counterpart 2D scratch wound assays. This underlines the need to use culturing techniques which better reflect the biological system in question, as the anti-migratory applications of these compounds have the potential to be missed if subjected to 2D screening only. The biological relevance of the model developed here was also increased by altering the culture microenvironment by the addition of extracellular matrix (ECM) coatings or co-culture, demonstrating that this model can be adapted to recreate a variety of microenvironments depending on the aims of the research undertaken. Together, the data presented in this thesis demonstrates the suitability of this novel culture system to assess the migratory behaviour of colorectal cancer cells in vitro, with the possibility of the adaption of this system to assess the behaviour of other cancer types.

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Yuting, Ma. "The crosstalk between dying tumor cells and immune effectors within tumor microenvironment elicited by anti-cancer therapies dictates the therapeutic outcome." Thesis, Paris 11, 2011. http://www.theses.fr/2011PA11T033/document.

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En dehors des effets cytostatiques ou cytotoxiques sur les cellules tumorales, certaines thérapies anti-cancéreuses peuvent déclencher la mort cellulaire immunogénique, libérant les signaux de danger pour alerter le système immunitaire. Les cellules T CD8+ T (Tc1) productrices d’IFN- et spécifiques de la tumeur sont nécessaires pour le succès de la chimiothérapie et la diminution de la croissance tumorale. L’amorçage d’une réponse bénéfique Tc1 dépend de la sécrétion d'IL-1β par les cellules dendritiques confrontées à des cellules tumorales traitées avec de l’anthracycline libérant de l’ATP. Pour identifier les composants inflammatoires qui lient les réponses immunitaires innées et adaptatives, nous avons analysé l'influence de la chimiothérapie immunogène sur le microenvironnement de la tumeur. Nous avons identifié une up-régulation de gènes associés à la réponse Th1 et Th17 dans un modèle de tumeur répondant au traitement par les anthracyclines par un retard de croissance. En interférant avec les voies IFN- ou l'IL-17A, l'effet thérapeutique de la doxorubicine et l'oxaliplatine a été aboli et le vaccin à base de cellules tumorales mortes ne protège plus les souris de la réintroduction de cellules tumorales vivantes. Nous avons également découvert que des sous-populations distinctes de lymphocytes T  (V4+ et V6+) colonisent des tumeurs peu de temps après la chimiothérapie, où ils ont proliféré et sont devenus producteurs majeurs de l’IL-17 au sein de la tumeur. Nous avons constaté une forte corrélation entre la présence de lymphocytes T  producteurs d’IL-17 ( T17) et de TIL CD8+ (Tc1) dans trois modèles différents de tumeurs traitées par la chimiothérapie ou la radiothérapie. IL-17A agit sur la signalisation en amont de l'IFN- puisqu’un défaut d’expression d’IL-17RA conduit à la perte complète de la production des Tc1 spécifiques de l’antigène. La contribution des cellules  T17 (V4+ et V6+) dans l’effet bénéfique de la chimiothérapie est essentielle puisque les souris V4/6-/-. L’axe IL-1β/IL-1R, mais pas IL-23/IL-23R, est essentielle pour la production d'IL-17 par les cellules T et l’effet bénéfique de la chimiothérapie. Le transfert adoptif de lymphocytes  T peut rétablir l'efficacité de la chimiothérapie dans le modèle de souris IL-17A-/- et améliorer l'effet de la chimiothérapie chez la souris wt, s'ils conservent l'expression de l'IL-1R et de l'IL-17A. Nos résultats suggèrent l’existence d’un axe fonctionnel: DC (IL-1β) → cellules T (IL-17) → Tc1 (IFN-), déclenché par la chimiothérapie induisant la mort des cellules tumorales, phénomène essentiel pour une réponse thérapeutique favorable. Pour renforcer la réponse immunitaire, nous essayons de combiner la chimiothérapie « immunogène » avec le vaccin anti-tumoral en présence d’adjuvants (poly (A:U), l'agoniste de TLR3).Ce type de thérapie séquentielle combinée, appelé VCT, pourrait retarder considérablement la croissance des tumeurs, voire l’éradiquer complètement et établir une protection spécifique à long terme. Pour décortiquer l'effet de la poly (A:U) sur le système immunitaire et sur les cellules tumorales exprimant le TLR3, nous avons effectué un traitement VCT chez la souris nude, TRIF-/- et les souris présentant une diminution de l’expression de TRIF au niveau des cellules tumorales. Ainsi l'effet anti-tumoral de VCT requiert les lymphocytes T et la voie de signalisation TRIF intacte au niveau de l'hôte et des cellules tumorales. Le traitement poly (A:U) peut induire un niveau élevé de production de certaines chimiokines associées à la réponse de type Th1 (CCL5 et CXCL10 ) par les cellules tumorales in vitro et in vivo, ce qui peut influencer négativement et positivement les résultats thérapeutiques. Le découplage de l’action de CCL5 et de XCL10, pourrait améliorer le traitement par la VCT. Notre étude souligne ainsi le rôle des facteurs inflammatoires dérivés de la tumeur et de l’hôte dans la régulation de la réponse immunitaire anti-tumorale
Besides exerting cytostatic or cytotoxic effects on tumor cells, some anti-cancer therapies (anthracyclines, oxaliplatin, X-Rays) could trigger an immunogenic cell death modality, releasing danger signals to alert immune system. We have shown that tumor-specific IFN- producing CD8+ T cells (Tc1) are mandatory for the success of chemotherapy to prevent tumor outgrowth. Priming of Tc1 response depends on IL-1β secretion by DC confronted with anthracycline-treated tumor cells releasing ATP. To identify the inflammatory components which link innate and cognate immune responses, we analyzed the influence of immunogenic chemotherapy on tumor microenvironment. We found an upregulated Th1- and Th17-related gene expression pattern in growth-retarded tumor after anthracycline treatment. By interfering with IFN- or IL-17A pathways, therapeutic effect of doxorubicin and oxaliplatin was abolished and dying tumor cell-based vaccine lost its efficacy to protect mice from live tumor cell rechallenge. Interestingly, we discovered that distinct subsets of  T lymphocytes (V4+ and V6+) colonized tumors shortly after chemotherapy, where they proliferated and became the dominant IL-17 producers within tumor beds. In three tumor models treated with chemotherapy or radiotherapy, a strong correlation between the presence of IL-17-producing  T ( T17) and IFN--producing CD8+ TIL (Tc1) was discovered. IL-17A signaling acts as upstream of IFN- since defect in IL-17RA led to complete loss of antigen specific Tc1 priming. The contribution of  T17 cells (V4+ and V6+) to chemotherapy is critical as V4/6-/- mice showed reduced sensitivity to chemotherapy and vaccination. Also, tumor infiltrating  T17 and Tc1 cells were reduced to basal level in this strain. IL-1β/IL-1R, but not IL-23/IL-23R, is pivotal for IL-17 production by  T cells and the success of chemotherapy. Importantly, adoptive transfer of  T cells could restore the efficacy of chemotherapy in IL-17A-/- mice and ameliorate the effect of chemotherapy in wild type host, provided that they retain the expression of IL-1R and IL-17A. Our research suggest a DC (IL-1β) →  T cells (IL-17) → Tc1 (IFN-) immune axis triggered by chemotherapy-induced dying tumor cells, which is critical for the favorable therapeutic response. To boost the immune system, we try to combine immunogenic chemotherapy with tumor vaccine in the presence of TLR3 agonist Poly (A:U). This sequential combined therapy, which we named VCT, could significantly retard tumor growth or even completely eradicate tumor and establish long-term protection against rechallenge in highly tumorigenic models. To dissect the effect of Poly (A:U) on immune system and that on TLR3 expressing-tumor cells, we performed VCT treatment in nude mice, TRIF-/- mice and with TRIF-silencing tumors. Interestingly, our results suggested that anti-tumor effect of VCT required T cells and intact TRIF signaling pathway at the level of the host and that of tumor cells. Poly (A:U) treatment could induce high level of CCL5 and CXCL10 production from tumor cells both in vitro and in vivo, which could negatively and positively influence the therapeutic outcome. By uncoupling the effect of CCL5 from that of CXCL10, the VCT treatment can be ameliorated. Our study emphasizes that both tumor and host derived inflammatory factors participate in regulating anti-tumor response. We also highlight that therapeutic application of TLR agonists can be optimized through regulating the profile of chemokines and their downstream signaling events

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Mola, Silvia. "Tumor Associated Macrophages (TAMs) a pivotal orchestrator in cancer-related inflammation and a new important target in cancer-therapy." Doctoral thesis, Università del Piemonte Orientale, 2021. https://hdl.handle.net/11579/127797.

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Macrophages are pivotal orchestrators of tumor-promoting inflammation and promising targets for new anti-cancer therapies. To identify new molecular players underlying their pro-tumoral activities, we analyzed the phosphoproteoma of tumor associated macrophages (TAMs) isolated from murine fibrosarcoma. We identified the protein TRIM28, a pleiotropic molecule that is known to be involved in the dynamic organization of chromatin, and we characterized the signaling pathway driving its phosphorylation in response to inflammatory signals and its impact on LPS-induced gene expression. We explored in vivo the functional relevance of TRIM28 and found a significant reduction of colitis associated cancer lesions in mice lacking TRIM28 in intestinal epithelial cells. Single cell RNAseq analysis pointed out alterations of both immune and intestinal cell populations during the transition from colitis to cancer, that are dependent on TRIM28. Overall, these results identify TRIM28 as a new molecular target at the crossroads between inflammation and cancer. Beyond contributing to tumorigenesis, TAMs can profoundly affect the response to anti-cancer therapies. We investigated their impact on EPZ-6438, an inhibitor of the histone methyltransferase EZH2 that has recently entered in clinical trials due to the anti-proliferative effects shown on malignant pleural mesothelioma cells (MPM). We generated an MPM spheroid model that recapitulates in vitro, both monocyte recruitment in tumor and their functional differentiation towards a TAM-like phenotype (Mo-TAMs) capable of promoting tumor cell proliferation and spreading. Prolonged treatment of MPM spheroids with EPZ-6438 enhances both Mo-TAMs recruitment and pro-tumor phenotype expression, thereby limiting the anti-proliferative effects due to EZH2 inhibition in MPM cells. These findings indicate that strategies of TAM depletion should be combined with EPZ-6438 to improve the therapeutic efficacy of pharmacological EZH2 inhibition.

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Moreno, Lama Lucía 1993. "Understanding the immunomodulatory role of PARP proteins in the response against tumors." Doctoral thesis, Universitat Pompeu Fabra, 2020. http://hdl.handle.net/10803/668471.

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Los inhibidores de PARP han surgido como nuevas terapias basadas en el papel essencial de las Poly (ADP-ribosa) polimerasas PARP-1 y PARP-2 en la respuesta a daño en el DNA, explotando el efecto de las mismas en la célula tumoral. Sin embargo, la progresión de un tumor está muy determinada por su compleja interacción con otros múltiples tipos celulares, particularmente las células T, en las que no se está considerando la actividad de PARP. Superando la letalidad embrionaria de los ratones doble deficientes en PARP-1 y PARP-2, en el presente trabajo investigamos el papel de estas PARPs en la modulación de las respuestas ejercidas por las células T contra tumores de mama inducidos por la línea AT-3; utilizando para ello ratones deficientes en PARP-1 con una supresión de PARP-2 controlada bajo el promotor de CD4. Descubrimos efectos opuestos de las deficiencias únicas y dobles, donde la doble supresión de PARP-1 y PARP-2 promueve el crecimiento tumoral mientras que la supresión individual de cada proteína limita la progresión del tumor. El análisis de las células infiltrantes de tumor en ratones con deficiencia doble de PARP-1 y PARP-2 reveló un cambio global en el perfil inmunológico y alteraciones en el reclutamiento y la activación de las células T. Por el contrario, la deficiencia única de PARP-1 o PARP-2 tiende a generar un microambiente con una respuesta inmune activa y parcialmente elevada.
Based on the essential role of Poly(ADP-ribose)-polymerases (PARP)-1 and PARP-2 in the DNA damage response, PARP inhibitors have emerged as novel therapeutic tools exploiting the effect of PARPs in the tumor cell itself. However, tumor progression is heavily determined by its complex interaction with multiple other cell types, particularly T cells, in which the activity of PARP is not being considered. Here, we bypassed the embryonic lethality of dually PARP-1/PARP-2-deficient mice by using a PARP-1- deficient mouse with a Cd4-promoter-driven deletion of PARP-2 in T cells to investigate the understudied role of these PARPs in the modulation of T cell responses against AT-3-induced breast tumors. We found opposite effects of single and dual deficiency in modulating the anti-tumor response; where dual PARP-1/PARP-2-deficiency in T cells promote tumor growth while single deficiency of each protein limited tumor progression. Analysis of tumor-infiltrating cells in dually PARP-1/PARP-2-deficiency host-mice revealed a global change in immunological profile and impaired recruitment and activation of T cells. Conversely, single PARP-1 and PARP-2-deficiency tends to produce an environment with an active and partially upregulated immune response.

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Hoque, Apu E. (Ehsanul). "Migration and invasion pattern analysis of oral cancer cells in vitro." Doctoral thesis, Oulun yliopisto, 2018. http://urn.fi/urn:isbn:9789526220239.

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Abstract Desmoglein 3 (Dsg3) is an adhesion receptor in desmosomes, but relatively little is known about its role in cancer. In this study, the function of Dsg3 was investigated in oral squamous cell carcinoma (SCC) cell lines in vitro using locally established human leiomyoma tumor microenvironment (TME) matrices. Since Dsg3 has been identified as a key regulator in cell adhesion, we hypothesized that it may play a role in oral SCC cells adhesion and motility. Thus, one aim of the study was to explore this hypothesis by both gain and loss of function methods in four human buccal mucosa SCC SqCC/Y1 cell lines: transduction of vector control (Ct), full-length (FL) or two different C-terminally truncated Dsg3 mutants (Δ238 and Δ560). Live cell imaging was performed for 2D migration and 3D sandwich, alongside other assays. In 3D sandwich, we tested the effects of the monoclonal antibody, AK23, targeting the extracellular domain of Dsg3 in SqCC/Y1 cells. Our results showed that loss of Dsg3 disrupted cell adhesion and protein expression. In 2D assays, FL and Dsg3 mutants migrated faster with higher accumulated distances than Ct. In contrast with 2D, mutants showed accelerated invasion over the Ct in 3D models. The AK23 antibody inhibited only the invasion of FL cells. The TME in vivo consists of cellular and matrix elements playing a leading role in carcinoma progression. To study carcinoma cells invasion in vitro, mouse Matrigel® and rat type 1 collagen are the most commonly used matrices in 3D models. Since they are non-human in origin, they do not perfectly mimic human TME. To address this, we have developed a solid organotypic myoma disc model derived from human uterus leiomyoma tumor. Here, we introduce a novel Myogel, prepared from leiomyoma similar to Matrigel®. We validated Myogel for cell-TME interactions in 3D models, using SqCC/Y1 and HSC-3 cell lines. Compared with Matrigel® and type I collagen, oral SCC cell lines invaded more efficiently in Myogel containing matrices. This study describes promising 3D models using human TME mimicking Myogel which is suitable to analyze oral SCC cells both in carcinoma monocultures and in co-cultures, such as with TME fibroblasts. We also introduce a possible novel therapeutic target against Dsg3 to suppress cancer cell invasion
Tiivistelmä Desmogleiini 3 (Dsg3) on desmosomien adheesioreseptori, jonka merkityksestä syövässä tiedetään vähän. Koska Dsg3 on tärkeä epiteelisolujen välisissä liitoksissa, oletimme sillä olevan vaikutusta myös suun karsinoomasolujen tarttumisessa ja niiden liikkuvuudessa. Testasimme hypoteesiamme muuttamalla Dsg3:n toimintaa ihmisen posken karsinoomasolulinjassa SqCC/Y1, josta oli aiemmin valmistettu neljä erilaista muunnosta: tyhjän vektorin sisältävä kontrollisolulinja (Ct), kokopitkää Dsg3 tuottava solulinja (FL), sekä kaksi Dsg3 C-päästä lyhennettyä mutanttisolulinjaa (Δ238 ja Δ560). Immunofluoresenssi-menetelmää käyttäen analysoimme solulinjoissamme solujen välisiä liitoksia. Lisäksi mittasimme solujen liikkeitä 2D-migraatio- ja 3D-sandwich-kokeissa. Testasimme myös Dsg3:n solunulkoista osaa tunnistavan monoklonaalisen vasta-aineen (AK23) vaikutusta solujen invaasioon. Osoitimme, että Dsg3:n rakenteen muuttaminen ja toiminnan estyminen häiritsi solujen tarttumista. 2D-kokeissa sekä FL että mutanttilinjat (Δ238 ja Δ560) migroivat kontrollisoluja nopeammin ja pidemmälle, mutta 3D-kokeissa vain mutanttilinjat invasoituivat kontrollisoluja tehokkaammin. AK23-vasta-aine esti vain FL-solujen invaasiota. Syöpäsolujen 3D-invaasiota mittaavissa kokeissa käytetään yleensä hiiren kasvaimesta valmistettua kaupallista Matrigeeliä® tai rotan kudoksista eristettyä tyypin I kollageenia. Tutkimusryhmämme on jo aiemmin kehittänyt organotyyppisen myoomamallin, jossa valmistamme myoomakudosnapit ihmisen kohdun leiomyoomakasvaimista. Tässä työssä valmistimme leiomyoomasta Myogeelia, vertasimme sitä Matrigeeliin®, sekä tutkimme tarkemmin Myogeeli-valmisteen soveltuvuutta 3D-tutkimuksiin. Totesimme, että kielen (HSC-3) ja posken (SqCC/Y1) karsinoomasolut invasoituivat tehokkaimmin Myogeeli-pitoisissa matrikseissa kuin Matrigeeliä® tai kollageeniä sisältävissä kasvatusalustoissa. Tutkimustulostemme perusteella Myogeeli-pohjaiset 3D-mallit soveltuvat hyvin sekä syöpäsolulinjojen invaasiotutkimuksiin että yhteisviljelmiin, joissa syöpäsoluja viljellään yhdessä syöpäkasvaimen ympärillä olevien solujen, kuten fibroblastien, kanssa

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Jalgaonkar, Swati. "An investigation of Atf3, an adaptive-response gene, in breast cancer chemotherapy and stress response." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1460387137.

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Dolega, Monika Elzbieta. "Developement of microtechnologies for 3D cell culture to study prostate acini formation and carcinogenesis." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENS022/document.

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Tout épithélium glandulaire sécrétoire est constitué d'une unité structurale et fonctionnelle commune, l'acinus. C'est une architecture sphérique pluricellulaire parfaitement différentiée et polarisée qui, reconstruite en culture 3D, mime l'organisation réelle du tissu. Etudier les déterminants environnementaux et génétiques qui gouvernent la transformation d'un acinus en sphéroïde s'apparentant à une tumeur est l'un des enjeux majeurs des modèles in vitro. Un des défis actuels est d'adapter ces modèles in vitro à des conditions de culture 3D qui soient compatibles avec la réalisation de cribles génétiques en 3D, basés par exemple sur l'ARN interférence (RNAi). Cependant, les formats standards de culture 3D et les méthodes analytiques ne sont pas compatibles aux cribles haut-débit. Ils ne permettent pas de contrôler la taille et la distribution des acini, sont dépendants d'immuno-marquages et les acquisitions sont longues. Par ailleurs, la microscopie confocale et vidéomicroscopie offrent un champ d'observation restreint qui ne permet pas d'observer un grand nombre de structures 3D en même temps, pour permettre une analyse statistique. Ainsi, dans le but i) de développer des modèles cellulaires appropriés en 3D, ii) d'adresser des questions fondamentales relatives au cancer de la prostate et iii) de réaliser des cribles RNAi dans un contexte plus pertinent que la culture 2D, j'ai développé des outils innovants au format microsystèmes adaptés à l'analyse haut-débit d'un grand nombre d'objets 3D. En optimisant les conditions de culture cellulaire 3D sur le modèle de la lignée cellulaire RWPE1, j'ai pu récapituler les étapes de formation des acini prostatiques et montrer que la formation du lumen est indépendante de la polarité et est gouvernée par deux mécanismes, « hollowing » et cavitation
In all secretory epithelia from glandular tissues, there is a common structural and functional unit, the acinus. It is a well polarized and organized pluricellular structure that is spontaneously reconstructed in 3D culture, therefore closely mimics the real structure we find in vivo. For my purpose, acini are used as models for tumor initiation and cancer development. One of the objectives of Biomics laboratory is to identify the genetic and microenvironmental determinants of prostate acini morphogenesis and polarity. The strategy is based on High-Throughput (HT) RNA interference (RNAi)-based screening. To meet this objective, my project was to develop appropriate 3D cell models which closely mimic the cyst-like and duct-like structure of prostate. By optimizing conventional 3D culture in Matrigel, I could recapitulate prostate acini morphogenesis and showed that lumen formation is independent to the polarity, which appears later. However, the conventional 3D cell culture formats and analytical tools are not suited for HT Screening (HTS). They lack control over acini size, are label-dependant and therefore time-consuming and labor intensive. Also, classical microscopy offers a very limited field of view and hence does not allow observing a large amount of 3D structures for statistical analysis

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Santos, Ana Paula Silva de Azevedo dos. "Efeito do microambiente tumoral sobre as características funcionais e fenotípicas de células dendríticas geradas in vitro a partir de monócitos do sangue periférico de voluntárias saudáveis e de pacientes com câncer de mama." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/42/42133/tde-13122010-112823/.

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No câncer de mama, o metabolismo tumoral, ação dos moduladores de estrógenos são fatores que podem influenciar as células dendríticas (DCs). Neste trabalho avaliou o fenótipo de DCs em amostras tumorais, a diferenciação de DCs a partir de células mononucleares do sangue periférico (PBMCs) das pacientes e comparou com voluntárias saudáveis. Os resultados mostraram que há alteração na capacidade de geração, no fenótipo, na capacidade aloestimuladora, maior produção de interleucina 10 e expressão de HSP27 nas DCs de pacientes, comparadas com as DCs de voluntárias saudáveis que produzem mais Interferon-gama. A via p38MAPK parece ser importante na diferenciação de PBMCs em DCs, entretanto, estímulos estressantes podem ativar esta via e induzir a síntese de HSP27 inibindo este processo. O tratamento com tamoxifeno parece modular a expressão de algumas moléculas de membrana. Desta forma, os resultados sugerem que as DCs diferenciadas de pacientes com câncer de mama apresentam alterações fenotípicas e funcionais causadas pelo microambiente tumoral.
In breast cancer, the tumor metabolism, the action of estrogens antagonists can influence dendritic cells (DC) generation. The aim of this work was to evaluate the frequency of DCs in tumor tissue and the differentiation of DCs derived from peripheral blood mononuclear cells (PBMCs) and compared the phenotypic and functionally of these cells from healthy individuals and breast cancer patients. The results showed that patients PBMCs were unable to generate phenotypicaly, functionally mature DCs and presented larger production of interleukin 10 and higher expression of HSP27 when compared with healthy volunteers\' DCs, presented higher production of Interferon-gamma. The p38 MAPK signaling pathway seems to be important in PBMCs differentiation into DCs, and its activation by stress can induce the synthesis of HSP27, that inhibits DC generation. The tamoxifen treatment caused modulation of membrane DC markers expression. Therefore, these results show that patients\' DCs present phenotypic and functional alterations which can be caused by tumor microenvironment.

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Petitprez, Florent. "Integrated analysis and clinical impact of immune and stromal microenvironments in solid tumors Quantitative analyses of the tumor microenvironment composition and orientation in the era of precision medicine Transcriptomic analysis of the tumor microenvironment to guide prognosis and immunotherapies Tumor microenvironment quantification tool draws a comprehensive map of the tumor microenvironment of non-hematologic human cancers The mMCP-counter method to estimate abundance of tissue-infiltrating immune and stromal cell populations using gene expression in murine samples Immune sub-classes in sarcoma predict survival and immunotherapy response Intra-tumoral tertiary lymphoid structures are associated with a low risk of hepatocellular carcinoma early recurrence Association of IL-36γ with tertiary lymphoid structures and inflammatory immune infiltrates in human colorectal cancer Immune-based identification of cancer patients at high risk of progression Tumor-infiltrating and peripheral blood T-cell immunophenotypes predict early relapse in localized clear cell renal cell carcinoma PD-L1 expression and CD8+ T-cell infiltrate are associated with clinical progression in patients with node-positive prostate cancer Intratumoral classical complement pathway activation promotes cancer progression." Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCB104.

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Les tumeurs sont composées de cellules malignes et d'une grande variété de cellules non-tumorales, en particulier des cellules immunitaires qui forment le micro-environnement tumoral (MET). Il a été démontré que la composition du MET était associée au devenir clinique des patients, en termes de survie et de réponses thérapeutiques. Avec le développement récent des immunothérapies qui ciblent des éléments spécifiques du MET, l'immunité anti-tumorale a soulevé un intérêt majeur. Plusieurs méthodologies ont été mises au point afin d'étudier la composition du MET, avec une précision toujours plus grande. En particulier, des méthodes comme MCP-counter permettent d'exploiter les données transcriptomiques de la tumeur entière afin de quantifier les différentes populations qui composent le MET. Le volet méthodologique de ce travail de thèse a ainsi consisté à proposer une amélioration de MCP-counter, en particulier pour l'analyse de données RNA-Seq. Une adaptation de la méthode pour des données issues de modèles murins (mMCP-counter) est également proposée. MCP-counter permet d'analyser rapidement le MET de larges séries de tumeurs. Un second volet de cette thèse consiste en l'application de cette méthode pour établir une classification immunitaire des sarcomes des tissus mous, un type de cancer rare, hétérogène et agressif. Cette classification immunitaire a permis de mettre en évidence des groupes de tumeurs faiblement ou fortement infiltrés, ainsi qu'un groupe marqué par une forte vascularisation. De manière intéressante, la classification immunitaire permet de prédire la réponse des patients aux immunothérapies. Ce travail a aussi démontré un rôle important des structures lymphoïdes tertiaires (SLT). Les SLT sont des structures de type noeud lymphatique composées de lymphocytes B et T qui se forment dans la tumeur ou à proximité de celle-ci. Au sein des SLT, une réponse immunitaire anti-tumorale peut se former et maturer. L'intérêt porté aux SLT est de plus en plus important pour de nombreux types de cancers. Dans la plupart des types de cancer, une forte infiltration de la tumeur par des lymphocytes T, en particulier CD8+, est associée à une meilleure survie des patients. Cependant, le carcinome rénal à cellules claires et le cancer de la prostate sont des exceptions à cette règle. En effet, dans ces deux cancers urologiques, la présence dans la tumeur de lymphocytes T est associée à une survie plus courte des patients, ainsi qu'à une rechute et une progression plus précoce. Ces exceptions sont détaillées dans une troisième partie de cette thèse, par une description minutieuse du MET, ainsi que par l'analyse de l'implication du système du complément. Dans leur ensemble, les résultats présentés dans cette thèse démontrent qu'en combinant différentes méthodes d'analyse, in silico, in situ et in vivo, il est possible d'obtenir une vision extrêmement complète du MET. La connaissance des types cellulaires présents dans la tumeur ainsi que leur orientation fonctionnelle permet de guider le soin apporté aux patients et d'améliorer leur devenir clinique. La description complète du MET ouvre la voie à une médecine personnalisée pour les patients atteints de cancer
Tumors are composed not only of malignant cells but also contain a vast variety of non-malignant cells, notably immune cells forming the tumor microenvironment (TME). The composition of the TME was shown to be associated with clinical outcome for cancer patients, in terms of survival and therapeutic responses. With the relatively recent development of immunotherapies targeting specific elements of the TME, tumor immunology has risen a strong interest and holds a strong therapeutic potential. Several methodologies have been developed to study the composition of the TME with an increased precision. Notably, some methods such as MCP-counter enable the use of the tumor bulk transcriptome to quantify cell populations composing the TME. The methodological aspect of this PhD project consisted in setting up an enhanced version of MCP-counter that can be readily applied to RNA-Seq data, as well as propose an adaptation of the method for mouse models. Using MCP-counter, the TME of large series of tumors can be easily analyzed. The application part of this PhD work consisted of applying MCP-counter to establish an immune-based classification of soft-tissue sarcoma, a rare, aggressive and heterogeneous cancer type. The immune classification notably allowed to identify immune low and high groups, and a group characterized by a strong vasculature. Interestingly, the classification was notably found to be predictive of the patients' response to immunotherapies. It also highlighted an important role of tertiary lymphoid structures (TLS). TLS are lymph-node-like structures composed of T and B cells that form within the tumor or in close proximity. They are a site of formation and maturation of antitumoral immune responses. TLS are raising a growing interest in many malignancies. In most cancer types, a strong infiltration by T cells, in particular CD8+ T cells, is associated with a favorable clinical outcome. However, clear-cell renal cell carcinoma and prostate cancer are exceptions to this general rule. Indeed, in these urological cancers, an increased infiltration by T cells is associated with a decreased patient survival and with earlier relapse and disease progression. In a third part of this thesis, these exceptions are investigated with more details by scrutinizing the TME, and questioning the implication of the complement system. Overall, this thesis presents how the combination of several analysis methods, in silico, in situ and in vivo, can help achieve an extremely precise description of the TME. Knowing accurately what cell populations and what their functional orientation can help guide patients care and improve clinical outcome. Complete description of the TME opens the way towards personalized medicine for cancer patients

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Bryson, Benjamin Levi. "The Paradoxical Roles of Oncostatin M in Mammary Epithelial Cell Senescence and Transformation." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1510584483133814.

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Väyrynen, O. (Otto). "Factors affecting aggressive oral tongue cancer invasion and development of in vitro models for chemoradiotherapy assay." Doctoral thesis, Oulun yliopisto, 2019. http://urn.fi/urn:isbn:9789526222813.

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Abstract Tumor associated macrophages (TAMs) are linked to the invasion of oral tongue squamous cell carcinoma (OTSCC). We modified THP-1 leukemia cells to M1 (inflammatory), M2 (TAM-like) and R848 (imidazoquinoline-treated) type macrophages in order to examine their interactions with OTSCC-cells (HSC-3) by using different kinds of in vitro migration and invasion models. We observed that interaction of TAM-resembling M2-type macrophages with HSC-3 cells induced invasion and migration, whereas the influence of M1 macrophages reduced them. Patient response to chemoradiotherapy is highly reliant on the characteristics such as the aggressiveness and stage of the cancer. Therefore, new methods for treatment testing are needed in order to design personalized therapies. We tested the applicability and consistency of human TME mimicking tissue methods for analyzing the effects of chemoradiation using commercial OTSCC cell lines. Based on our trials, both our human uterine leiomyoma tissue -based matrix models provide viable platforms for future in vitro chemoradiotherapy testing. Conventionally pro-tumorigenic activities of matrix metalloproteinase (MMP)9 have been linked with oral squamous cell carcinoma, but recently its tumor-suppressor role has also been revealed. Our study provides strong evidence that MMP9 also has an anti-invasive effect in OTSCC and is a potential mediator of the protective effects of arresten in tongue cancer cells
Tiivistelmä Makrofageilla on yhteys kielen levyepiteelikarsinooman invaasioon eli syöpäkasvaimen tunkeutumiseen ympäröivään kudokseen. Tutkimuksessamme muokkasimme ihmisen THP-1 leukemiasoluja kemiallisesti tulehdusreittejä aktivoiviksi M1-makrofageiksi, kasvaimeen liittyvien makrofagien kaltaisiksi M2-makrofageiksi sekä imidatsokinoliini-käsitellyiksi R848-makrofageiksi. Tarkoituksenamme oli tutkia makrofagien ja kielisyöpäsolujen vuorovaikutuksia erilaisilla in vitro migraatio- ja invaasiomalleilla. Anti-inflammatoristen, syövän etenemistä edesauttavien TAM-makrofagien kaltaisiksi erilaistetut M2-tyypin makrofagit lisäsivät HSC-3 kielikarsinoomasolujen invaasiota ja migraatiota, kun taas M1-tyypin makrofagien vaikutus oli päinvastainen. Potilaan vaste kemosädehoitoon riippuu syöpäkasvaimen ominaisuuksista, kuten syöpäsolujen aggressiivisuudesta ja syövän levinneisyysasteesta. Tämän vuoksi on tarve uusille menetelmille, joiden avulla voidaan ottaa huomioon potilaan sekä syöpätyypin yksilölliset ominaisuudet hoitoa suunniteltaessa. Testasimme syöpäkasvaimen mikroympäristöä mallintavien, ihmiskudokseen perustuvien menetelmien käyttökelpoisuutta ja luotettavuutta kemosädehoidon vaikutusten arvioimiseen. Testiemme perusteella myoomakudokseen pohjautuvat menetelmät voivat auttaa kemosädehoidon vaikutusten testauksessa. Matriksin metalloproteinaasi (MMP) 9:n on pitkään uskottu olevan yksinomaan syövän etenemistä edesauttava molekyyli. Viimeaikaisissa tutkimuksissa on myös havaittu, että MMP9:llä voi olla syövältä suojaavia vaikutuksia. Tutkimme MMP9:n vaikutusta kielisyöpäsoluihin ja havaitsimme, että MMP9:llä on myös invaasiota hillitseviä vaikutuksia. Lisäksi MMP9 saattaa toimia verisuonten muodostumista estävän arresten-molekyylin syövältä suojaavien mekanismien välittäjänä

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Bin, Saeedan Abdulaziz Saad Abdulaziz. "The role of MMP10 in non-small cell lung cancer, and pharmacological evaluation of its potential as a target for therapeutic intervention : investigation of the role of MMP10 in the tumour microenvironment of non-small cell lung cancer using gene, protein and mass spectrometry approaches to determine MMP10's potential in drug development strategies." Thesis, University of Bradford, 2014. http://hdl.handle.net/10454/14070.

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Bin, Saeedan Abdulaziz S. A. "The role of MMP10 in non-small cell Lung cancer, and pharmacological evaluation of its potential as a target for therapeutic intervention. Investigation of the role of MMP10 in the tumour microenvironment of non-small cell lung cancer using gene, protein and mass spectrometry approaches to determine MMP10’s potential in drug development strategies." Thesis, University of Bradford, 2014. http://hdl.handle.net/10454/14070.

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Non-Small Cell Lung Cancer (NSCLC), which accounts for 80% of all lung cancer cases, is associated with resistance to chemotherapy and poor prognosis. Exploitation of NSCLC-upregulated pathways that can either be targeted by novel therapeutics or used to improve the tumour-delivery of current chemotherapeutics are required. Among the matrix metalloproteinases (MMPs) that are essential for tumour development, MMP10 is a potential candidate as a therapeutic target based on its expression and contribution to NSCLC development. This research aims to explore the expression and functions of MMP10 in the tumour microenvironment of NSCLC and evaluate the potential of MMP10 as a target for therapeutic intervention. Herein, MMP10 expression at gene and protein levels were analysed in a panel of NSCLC cell lines using RT-PCR and Western blotting analysis. To determine MMP10 functional relevance, an in vitro angiogenesis assay using cell conditioned media was carried out. To identify specific peptide sequences for the design of prodrugs rationalised to be MMP10 activated, in vitro substrate cleavage studies were performed using a mass spectrometry approach to differentiate between MMP10 and the structurally similar MMP3. This study demonstrates that MMP10 is highly expressed in NSCLC and that high levels of MMP10 are associated with induction of angiogenesis, a crucial process supporting tumour growth. In addition to the achievement of having been able to differentiate between closely similar MMP3 and MMP10 through carefully monitoring the hydrolysis rate of compound 444259 (a known MMP substrate), data generated herein provides the basis for further studies to exploit MMP10 as a prodrug-activator.
Full text was made available at the end of the embargo period, 12th Dec 2019

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Lawrence, Mitchell Graham. "Crosstalk between developmental and tumour-specific signalling pathways : kallikrein-related serine peptidases and nodal in prostrate cancer." Thesis, Queensland University of Technology, 2009. https://eprints.qut.edu.au/37184/1/Mitchell_Lawrence_Thesis.pdf.

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Prostate cancer is an important male health issue. The strategies used to diagnose and treat prostate cancer underscore the cell and molecular interactions that promote disease progression. Prostate cancer is histologically defined by increasingly undifferentiated tumour cells and therapeutically targeted by androgen ablation. Even as the normal glandular architecture of the adult prostate is lost, prostate cancer cells remain dependent on the androgen receptor (AR) for growth and survival. This project focused on androgen-regulated gene expression, altered cellular differentiation, and the nexus between these two concepts. The AR controls prostate development, homeostasis and cancer progression by regulating the expression of downstream genes. Kallikrein-related serine peptidases are prominent transcriptional targets of AR in the adult prostate. Kallikrein 3 (KLK3), which is commonly referred to as prostate-specific antigen, is the current serum biomarker for prostate cancer. Other kallikreins are potential adjunct biomarkers. As secreted proteases, kallikreins act through enzyme cascades that may modulate the prostate cancer microenvironment. Both as a panel of biomarkers and cascade of proteases, the roles of kallikreins are interconnected. Yet the expression and regulation of different kallikreins in prostate cancer has not been compared. In this study, a spectrum of prostate cell lines was used to evaluate the expression profile of all 15 members of the kallikrein family. A cluster of genes was co-ordinately expressed in androgenresponsive cell lines. This group of kallikreins included KLK2, 3, 4 and 15, which are located adjacent to one another at the centromeric end of the kallikrein locus. KLK14 was also of interest, because it was ubiquitously expressed among the prostate cell lines. Immunohistochemistry showed that these 5 kallikreins are co-expressed in benign and malignant prostate tissue. The androgen-regulated expression of KLK2 and KLK3 is well-characterised, but has not been compared with other kallikreins. Therefore, KLK2, 3, 4, 14 and 15 expression were all measured in time course and dose response experiments with androgens, AR-antagonist treatments, hormone deprivation experiments and cells transfected with AR siRNA. Collectively, these experiments demonstrated that prostatic kallikreins are specifically and directly regulated by the AR. The data also revealed that kallikrein genes are differentially regulated by androgens; KLK2 and KLK3 were strongly up-regulated, KLK4 and KLK15 were modestly up-regulated, and KLK14 was repressed. Notably, KLK14 is located at the telomeric end of the kallikrein locus, far away from the centromeric cluster of kallikreins that are stimulated by androgens. These results show that the expression of KLK2, 3, 4, 14 and 15 is maintained in prostate cancer, but that these genes exhibit different responses to androgens. This makes the kallikrein locus an ideal model to investigate AR signalling. The increasingly dedifferentiated phenotype of aggressive prostate cancer cells is accompanied by the re-expression of signalling molecules that are usually expressed during embryogenesis and foetal tissue development. The Wnt pathway is one developmental cascade that is reactivated in prostate cancer. The canonical Wnt cascade regulates the intracellular levels of β-catenin, a potent transcriptional co-activator of T-cell factor (TCF) transcription factors. Notably, β-catenin can also bind to the AR and synergistically stimulate androgen-mediated gene expression. This is at the expense of typical Wnt/TCF target genes, because the AR:β-catenin and TCF:β-catenin interactions are mutually exclusive. The effect of β-catenin on kallikrein expression was examined to further investigate the role of β-catenin in prostate cancer. Stable knockdown of β-catenin in LNCaP prostate cancer cells attenuated the androgen-regulated expression of KLK2, 3, 4 and 15, but not KLK14. To test whether KLK14 is instead a TCF:β-catenin target gene, the endogenous levels of β-catenin were increased by inhibiting its degradation. Although KLK14 expression was up-regulated by these treatments, siRNA knockdown of β-catenin demonstrated that this effect was independent of β-catenin. These results show that β-catenin is required for maximal expression of KLK2, 3, 4 and 15, but not KLK14. Developmental cells and tumour cells express a similar repertoire of signalling molecules, which means that these different cell types are responsive to one another. Previous reports have shown that stem cells and foetal tissues can reprogram aggressive cancer cells to less aggressive phenotypes by restoring the balance to developmental signalling pathways that are highly dysregulated in cancer. To investigate this phenomenon in prostate cancer, DU145 and PC-3 prostate cancer cells were cultured on matrices pre-conditioned with human embryonic stem cells (hESCs). Soft agar assays showed that prostate cancer cells exposed to hESC conditioned matrices had reduced clonogenicity compared with cells harvested from control matrices. A recent study demonstrated that this effect was partially due to hESC-derived Lefty, an antagonist of Nodal. A member of the transforming growth factor β (TGFβ) superfamily, Nodal regulates embryogenesis and is re-expressed in cancer. The role of Nodal in prostate cancer has not previously been reported. Therefore, the expression and function of the Nodal signalling pathway in prostate cancer was investigated. Western blots confirmed that Nodal is expressed in DU145 and PC-3 cells. Immunohistochemistry revealed greater expression of Nodal in malignant versus benign glands. Notably, the Nodal inhibitor, Lefty, was not expressed at the mRNA level in any prostate cell lines tested. The Nodal signalling pathway is functionally active in prostate cancer cells. Recombinant Nodal treatments triggered downstream phosphorylation of Smad2 in DU145 and LNCaP cells, and stably-transfected Nodal increased the clonogencity of LNCaP cells. Nodal was also found to modulate AR signalling. Nodal reduced the activity of an androgen-regulated KLK3 promoter construct in luciferase assays and attenuated the endogenous expression of AR target genes including prostatic kallikreins. These results demonstrate that Nodal is a novel example of a developmental signalling molecule that is reexpressed in prostate cancer and may have a functional role in prostate cancer progression. In summary, this project clarifies the role of androgens and changing cellular differentiation in prostate cancer by characterising the expression and function of the downstream genes encoding kallikrein-related serine proteases and Nodal. Furthermore, this study emphasises the similarities between prostate cancer and early development, and the crosstalk between developmental signalling pathways and the AR axis. The outcomes of this project also affirm the utility of the kallikrein locus as a model system to monitor tumour progression and the phenotype of prostate cancer cells.

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Eriksson, Emma. "Preclinical evaluation of immunostimulatory gene therapy for pancreatic cancer." Doctoral thesis, Uppsala universitet, Institutionen för immunologi, genetik och patologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-330189.

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Pancreatic cancer is characterized by its desmoplastic tumor microenvironment and the infiltration of immunosuppressive cells. It is a devastating disease where most patients are diagnosed at a late stage and the treatment options are few. The development of new treatments is surly needed. One treatment option explored is the use of immunotherapy with the intent to activate the immune system and change the balance from pro-tumor to anti-tumor. This thesis presents the idea of using oncolytic adenoviruses called LOAd-viruses that are armed with immunostimulatory- and microenvironment-modulating transgenes. For effective treatment of pancreatic cancer, the virus needs to be able to be given in addition to standard therapy, the chemotherapy gemcitabine. In paper I, the immunomodulatory effect of gemcitabine was evaluated in blood from pancreatic cancer patients receiving their first 28-day cycle of treatment with infusions day 1, 8 and 15 followed by a resting period. Gemcitabine reduced the level of immunosup-pressive cells and molecules but the effect did not last throughout the resting period. On the other hand, gemcitabine did not affect the level or proliferative function of effector T cells indicating that gemcitabine could be combined with immunotherapy. The LOAd700 virus expresses a novel membrane-bound trimerized form of CD40L (TMZ-CD40L). In paper II, LOAd700 showed to be oncolytic in pancreatic cancer cell lines as well as being immunostimulatory as shown by its capacity to activate dendritic cells (DCs), myeloid cells, endothelium, and to promote expansion of antigen-specific T cells. In paper III, LOAd703 armed with both 4-1BBL and TMZ-CD40L was evaluated. LOAd703 gave a more profound effect than LOAd700 on activation of DCs and the virus was also capable of reducing factors in stellate cells connected to the desmo-plastic and immunosuppressive microenvironment. In paper IV, LOAd713 armed with TMZ-CD40L in combination with a single-chain variable fragment against IL-6R was evaluated. The virus could kill pancreatic cancer cells lines through oncolysis and could also reduce factors involved in desmoplasia in stellate cells. Most interestingly, LOAd713 could reduce the up-regulation of PD-1/PD-L1 in DCs after CD40 activation. Taken together, LOAd703 and LOAd713 seem to have interesting features with their combination of immunostimulation and microenvironment modulation. At present, LOAd703 is evaluated in a clinical trial for pancreatic cancer (NCT02705196).

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Dissertations / Theses on the topic 'Cancer cell microenvironment'

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