Artículos de revistas: "Comparison with in vitro cultures and in vivo xenografts"

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Chen, Selby, Timothy Peterson, S. Keith Anderson, Jeanette Eckel-Passow, Paul A. Decker, Jann Nagina Sarkaria y Ian F. Parney. "Genotypes of human glioma xenografts compared with glioma stem cell-derived tumors." Journal of Clinical Oncology 31, n.º 15_suppl (20 de mayo de 2013): 2072. http://dx.doi.org/10.1200/jco.2013.31.15_suppl.2072.

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2072 Background: Human glioma stem cells and xenograft lines are common translational models in neuro-oncology but it has not been established if they are genetically and phenotypically comparable. This study aimed to determine if human glioma xenografts and stem cell-derived tumors had similar genotypes. Methods: Matched glioma stem cell cultures and subcutaneous xenograft lines were generated from four human glioblastoma specimens (BT114, BT116, BT120, BT132). Comparison was made between subcutaneous stem cell-derived tumors (flank) and xenografts established in nude mice. Copy number variation (CNV) and gene expression microarray studies were performed. Results: Various differences in copy number and gene expression were seen. Observed CNVs included regions within EGFR, myc, and p16 (INK). For example, EGFR copy number was two fold higher in xenografts vs. stem cell-derived tumor in one line (BT114). This difference was corroborated by western blot. Other differences included a heat shock protein homolog (DNAJA4), tetraspanin 13, and a p53 family target gene (ISG20L1). Two lines (BT114, BT116) had a greater than two fold increase in DNAJA4 expression in xenografts vs. stem cell-derived tumors (p = 0.04, 0.01). Two cell lines (BT116, BT120) had a two to eight fold increase in tetraspanin 13 expression in xenografts (p = 0.02, 0.05). However, neither copy number nor gene expression variations were consistent across all cell lines. Conclusions: Xenografts and glioma stem cell-derived tumors established from the same patient specimens have distinct genotypes. Further work is needed to establish if these differences are random or represent characteristic changes selected by different in vitro or in vivo pressures. However, these variations raise questions regarding which model is ideal for studying glioma biology, and which ones best replicate glioma characteristics in human patients.

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Nelius, Thomas, Courtney Jarvis, Dalia Martinez-Marin y Stephanie Filleur. "Comparison of docetaxel and cabazitaxel efficacy on prostate cancer cells both in vitro and in vivo." Journal of Clinical Oncology 34, n.º 2_suppl (10 de enero de 2016): 351. http://dx.doi.org/10.1200/jco.2016.34.2_suppl.351.

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351 Background: Despite recently approved novel agents, taxane-based chemotherapy remains the major therapeutic strategy for metastatic castration-refractory prostate cancer/mCRPC. Still mCRPC continues to be incurable. Besides, patients often experience severe side effects, prompting a re-evaluation of standard regimen. Past studies have demonstrated promise for Low-Dose Metronomic/LDM chemotherapy, defined as the frequent administration of low doses of chemotherapeutic drugs with no prolonged drug-free breaks. Yet relative activities of LDM taxanes and combinations with known anti-neoplasic agents have to be investigated. Methods: PC3, Du145 and LNCaP-derivative CL1cell lines were used to compare the effect of increasing doses of taxanes on cell proliferation, cell cycle distribution and apoptosis by crystal violet, propidium iodide and AnnexinV stainings, respectively. Autophagy was assessed by western blotting against Beclin1. In vivotumor growth was measured using CL1 control and CL1-PEDF xenografts. Phagocytosis was determined by cytotoxicity assay in CL1-macrophages co-cultures. Results: Our data showed that cabazitaxel/cbz-treated cells had a significantly lower EC50 compared to docetaxel/doc, with Du145 cells presenting the greatest differences. Both low-dose taxanes increased the sub-G0 cells population. However, the sub-G0 increase was significantly greater in cbz- than doc-treated Du145 cells, but not in PC3 and CL1. Accordingly, plasma membrane Annexin V elevation occurred in Du145 cells at lower doses of cbz than doc validating a higher efficacy due to increased apoptosis. Although Beclin1 levels remain unchanged in PC3 and CL1 cells, it was found up-regulated for all doses of cbz in Du145. In vivo, LDM cbz was significantly more efficient in curbing tumor growth than doc. This effect was markedly increased when cbz was combined with the angio-inhibitor and anti-tumor Pigment Epithelium-Derived Factor (PEDF); an effect that could be explained by increased phagocytosis. Conclusions: Our data demonstrate a higher efficacy of cbz on CRPC both in vitro and in vivo, and suggest that LDM taxane chemotherapy/PEDF combination could be used as a novel therapeutic strategy for CRPC.

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Harvell, Djuana M. E., Jennifer K. Richer, D. Craig Allred, Carol A. Sartorius y Kathryn B. Horwitz. "Estradiol Regulates Different Genes in Human Breast Tumor Xenografts Compared with the Identical Cells in Culture". Endocrinology 147, n.º 2 (1 de febrero de 2006): 700–713. http://dx.doi.org/10.1210/en.2005-0617.

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In breast cancers, estrogen receptor (ER) levels are highly correlated with response to endocrine therapies. We sought to define mechanisms of estrogen (E) signaling in a solid breast tumor model using gene expression profiling. ER+ T47D-Y human breast cancer cells were grown as xenografts in ovariectomized nude mice under four conditions: 1) 17β-estradiol for 8 wk (E); 2) without E for 8 wk (control); 3) E for 7 wk followed by 1 wk of E withdrawal (Ewd); or 4) E for 8 wk plus tamoxifen for the last week. E-regulated genes were defined as those that differed significantly between control and E and/or between E and Ewd or control and Ewd. These protocols generated 188 in vivo E-regulated genes that showed two major patterns of regulation. Approximately 46% returned to basal states after Ewd (class I genes); 53% did not (class II genes). In addition, more than 70% of class II-regulated genes also failed to reverse in response to tamoxifen. These genes may be interesting for the study of hormone-resistance issues. A subset of in vivo E-regulated genes appears on lists of clinical ER discriminator genes. These may be useful therapeutic targets or markers of E activity. Comparison of in vivo E-regulated genes with those regulated in identical cells in vitro after 6 and 24 h of E treatment demonstrate only 11% overlap. This indicates the extent to which gene expression profiles are uniquely dependent on hormone-treatment times and the cellular microenvironment.

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Restifo, Diana, Aditya Kulkarni, Caleb Schimke, Joseph McDermott, Umesh Kathad, Kishor Bhatia, Panna Sharma y Igor Astsaturov. "Abstract PO-036: LP184, a novel alkylating agent, is highly effective in pancreatic cancers with DNA damage repair defects". Cancer Research 81, n.º 22_Supplement (15 de noviembre de 2021): PO—036—PO—036. http://dx.doi.org/10.1158/1538-7445.panca21-po-036.

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Abstract Biomarker-based chemotherapy with increased efficacy and prolonged disease-free survival are urgently needed in pancreatic cancer (PDAC). A 15-20% subset of PDAC tumors carry mutations in DNA repair pathway (BRCA1/BRCA2/PALB2/RAD51/ATM/FANCD2). Additionally, mutations in nucleotide excision repair (NER) genes (ERCC2/3/4/5/6) have been reported in ~5% of PDAC. LP184 is a novel synthetic small molecule acylfulvene analog. Using precise synthetic chemistry, we determined that only a negative enantiomer of LP184 is converted to an active alkylating agent in the strict dependency on oxidoreductase, prostaglandin reductase 1 (PTGR1). By computational analyses, we demonstrate a strong positive correlation of LP184 sensitivity with PTGR1 transcript levels (r=0.89, p<10−15) in a broad panel of cancer cell lines. Once activated by PTGR1, highly reactive LP-184 nucleophile creates covalent DNA adducts that are selectively repaired via Nucleotide Excision Repair (NER) mechanism coupled to transcription (TC-NER) and/or homologous recombination (HR). We reasoned that mutation or expression driven TC-NER and HR deficiency would predispose PDAC cells to increased sensitivity to LP184. To test the idea of LP184 activity in DNA repair-deficient tumors, we evaluated LP184 chemosensitivity in genetically defined PDAC models in vitro, ex vivo, and in xenografts. Testing in six different pancreatic cancer cell lines (Capan-1, CFPAC-1, Panc1, MiaPaCa2, Panc03.27 and BxPC-3) resulted in very potent inhibition with LP184 IC50 values ranging from 114 to 182 nM. In this cell line panel, LP184 sensitivity correlated negatively with transcript levels of an NER pathway gene ERCC8 (r = -0.94). In comparison to these PDAC cell lines, a normal pancreatic epithelial cell line HPNE was 3-6 times less sensitive to LP184 (IC50 670 nM). Ex vivo cultures of 4 out of 5 low-passage patient-derived xenografts with HR deficiency showed nanomolar sensitivity to LP184 with IC50s ranging from 45 to 270 nM. These tumor graft models which were at least 6 times less sensitive to olaparib in the same assay. Depletion of ERCC4 enhanced sensitivity to LP184 about 2-fold relative to the parental cell line. To define PTGR1 as a biomarker for LP184 activity, we used CRISPR/Cas9-mediated gene editing to deplete PTGR1 expression. We found PTGR1-null Capan-1 cell line-derived xenografts were poorly sensitive to LP184, whereas PTGR1-expressing xenografts showed near complete tumor regression in all LP184 treated animals with 109% tumor growth inhibition relative to the control group in this study. Furthermore, PTGR1 depleted cells were completely resistant to LP184 in vitro. Our preclinical data demonstrate that PDAC models carrying a range of DNA repair pathway mutations are highly sensitive to LP-184 in vitro and in vivo. Increased PTGR1 expression is a validated biomarker for LP184 cytotoxicity, and is the exclusive convertase of LP184 to an active alkylator drug. We anticipate LP184 will extend the therapeutic opportunities to a large subset of PDAC patients carrying these genetic alterations. Citation Format: Diana Restifo, Aditya Kulkarni, Caleb Schimke, Joseph McDermott, Umesh Kathad, Kishor Bhatia, Panna Sharma, Igor Astsaturov. LP184, a novel alkylating agent, is highly effective in pancreatic cancers with DNA damage repair defects [abstract]. In: Proceedings of the AACR Virtual Special Conference on Pancreatic Cancer; 2021 Sep 29-30. Philadelphia (PA): AACR; Cancer Res 2021;81(22 Suppl):Abstract nr PO-036.

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Garcia, Patrick L., Aubrey L. Miller y Karina J. Yoon. "Patient-Derived Xenograft Models of Pancreatic Cancer: Overview and Comparison with Other Types of Models". Cancers 12, n.º 5 (22 de mayo de 2020): 1327. http://dx.doi.org/10.3390/cancers12051327.

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Pancreatic cancer (PC) is anticipated to be second only to lung cancer as the leading cause of cancer-related deaths in the United States by 2030. Surgery remains the only potentially curative treatment for patients with pancreatic ductal adenocarcinoma (PDAC), the most common form of PC. Multiple recent preclinical studies focus on identifying effective treatments for PDAC, but the models available for these studies often fail to reproduce the heterogeneity of this tumor type. Data generated with such models are of unknown clinical relevance. Patient-derived xenograft (PDX) models offer several advantages over human cell line-based in vitro and in vivo models and models of non-human origin. PDX models retain genetic characteristics of the human tumor specimens from which they were derived, have intact stromal components, and are more predictive of patient response than traditional models. This review briefly describes the advantages and disadvantages of 2D cultures, organoids and genetically engineered mouse (GEM) models of PDAC, and focuses on the applications, characteristics, advantages, limitations, and the future potential of PDX models for improving the management of PDAC.

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Hoare, Owen, Nicolas Fraunhoffer, Abdessamad Elkaoutari, Odile Gayet, Martin Bigonnet, Julie Roques, Rémy Nicolle et al. "Exploring the Complementarity of Pancreatic Ductal Adenocarcinoma Preclinical Models". Cancers 13, n.º 10 (19 de mayo de 2021): 2473. http://dx.doi.org/10.3390/cancers13102473.

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Purpose: Compare pancreatic ductal adenocarcinoma (PDAC), preclinical models, by their transcriptome and drug response landscapes to evaluate their complementarity. Experimental Design: Three paired PDAC preclinical models—patient-derived xenografts (PDX), xenograft-derived pancreatic organoids (XDPO) and xenograft-derived primary cell cultures (XDPCC)—were derived from 20 patients and analyzed at the transcriptomic and chemosensitivity level. Transcriptomic characterization was performed using the basal-like/classical subtyping and the PDAC molecular gradient (PAMG). Chemosensitivity for gemcitabine, irinotecan, 5-fluorouracil and oxaliplatin was established and the associated biological pathways were determined using independent component analysis (ICA) on the transcriptome of each model. The selection criteria used to identify the different components was the chemosensitivity score (CSS) found for each drug in each model. Results: PDX was the most dispersed model whereas XDPO and XDPCC were mainly classical and basal-like, respectively. Chemosensitivity scoring determines that PDX and XDPO display a positive correlation for three out of four drugs tested, whereas PDX and XDPCC did not correlate. No match was observed for each tumor chemosensitivity in the different models. Finally, pathway analysis shows a significant association between PDX and XDPO for the chemosensitivity-associated pathways and PDX and XDPCC for the chemoresistance-associated pathways. Conclusions: Each PDAC preclinical model possesses a unique basal-like/classical transcriptomic phenotype that strongly influences their global chemosensitivity. Each preclinical model is imperfect but complementary, suggesting that a more representative approach of the clinical reality could be obtained by combining them. Translational Relevance: The identification of molecular signatures that underpin drug sensitivity to chemotherapy in PDAC remains clinically challenging. Importantly, the vast majority of studies using preclinical in vivo and in vitro models fail when transferred to patients in a clinical setting despite initially promising results. This study presents for the first time a comparison between three preclinical models directly derived from the same patients. We show that their applicability to preclinical studies should be considered with a complementary focus, avoiding tumor-based direct extrapolations, which might generate misleading conclusions and consequently the overlook of clinically relevant features.

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Bayley, Nicholas, Christopher Tse, Lynn Baufeld, Laura Gosa, Weihong Yan, Henan Zhu, Nikolas Balanis et al. "TMIC-26. PRECLINICAL MODEL SYSTEMS OF GLIOBLASTOMA REVEAL MICROENVIRONMENTAL PROGRAMS AND DEPENDENCIES IN PATIENT TUMORS". Neuro-Oncology 21, Supplement_6 (noviembre de 2019): vi253. http://dx.doi.org/10.1093/neuonc/noz175.1060.

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Abstract Patient-derived model systems serve as a platform for translational research representing the heterogeneity of human cancers, and their success in recapitulating disease-driving genomic alterations is well-documented. While recent studies have demonstrated genomic and functional divergence in patient-derived models with passaging, the need for accurate preclinical models remains. Glioblastoma (GBM) is the most common and aggressive primary brain tumor, and thus far preclinical models have failed to consistently replicate the responses found in patients. We therefore aimed to evaluate the multi-omic fidelity of low-passage GBM model systems across in vitro and in vivo environments and to elucidate the molecular features in which they differ. To this end we established a biobank of glioma direct-from-patient orthotopic xenograft (GliomaPDOX) models and primary gliomasphere cultures (GSCs) and performed whole-exome and RNA sequencing of over 40 purified patient tumors and their matched GliomaPDOXs and GSCs to facilitate paired comparisons across a gradient of full tumor microenvironment (TME) presence. We observed global genomic and transcriptomic fidelity in both systems, but specific programmatic gene expression differences associated with cell-cell interactions in the brain TME, glial cell identity, and in vitro GSC-forming ability. GSCs and GSC-forming ability are strongly associated with an astrocytic gene expression signature, while more stem-like and oligodendrocytic patient tumors including IDH- and H3F3A-mutant GBMs more successfully engraft in GliomaPDOXs. This result implicates the brain TME as a support system for these more stem/oligo-like tumors. Transcription factor network analysis identified regulators of the NOTCH and MYC pathways as strongly enriched in this subgroup of patient tumors and their derivative xenografts, and provides potential targets for therapeutic intervention in near future experiments. Collectively, these findings underline the critical role of the TME in defining GBM cell state, reveal the heterogeneity of TME dependence across patient tumors, and link this dependency to therapeutically actionable molecular features.

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Karikari, Isaac O., Christopher L. Gilchrist, Liufang Jing, David A. Alcorta, Jun Chen, William J. Richardson, Mostafa A. Gabr et al. "Molecular characterization of chordoma xenografts generated from a novel primary chordoma cell source and two chordoma cell lines". Journal of Neurosurgery: Spine 21, n.º 3 (septiembre de 2014): 386–93. http://dx.doi.org/10.3171/2014.4.spine13262.

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Object Chordoma cells can generate solid-like tumors in xenograft models that express some molecular characteristics of the parent tumor, including positivity for brachyury and cytokeratins. However, there is a dearth of molecular markers that relate to chordoma tumor growth, as well as the cell lines needed to advance treatment. The objective in this study was to isolate a novel primary chordoma cell source and analyze the characteristics of tumor growth in a mouse xenograft model for comparison with the established U-CH1 and U-CH2b cell lines. Methods Primary cells from a sacral chordoma, called “DVC-4,” were cultured alongside U-CH1 and U-CH2b cells for more than 20 passages and characterized for expression of CD24 and brachyury. While brachyury is believed essential for driving tumor formation, CD24 is associated with healthy nucleus pulposus cells. Each cell type was subcutaneously implanted in NOD/SCID/IL2Rγnull mice. The percentage of solid tumors formed, time to maximum tumor size, and immunostaining scores for CD24 and brachyury (intensity scores of 0–3, heterogeneity scores of 0–1) were reported and evaluated to test differences across groups. Results The DVC-4 cells retained chordoma-like morphology in culture and exhibited CD24 and brachyury expression profiles in vitro that were similar to those for U-CH1 and U-CH2b. Both U-CH1 and DVC-4 cells grew tumors at rates that were faster than those for U-CH2b cells. Gross tumor developed at nearly every site (95%) injected with U-CH1 and at most sites (75%) injected with DVC-4. In contrast, U-CH2b cells produced grossly visible tumors in less than 50% of injected sites. Brachyury staining was similar among tumors derived from all 3 cell types and was intensely positive (scores of 2–3) in a majority of tissue sections. In contrast, differences in the pattern and intensity of staining for CD24 were noted among the 3 types of cell-derived tumors (p < 0.05, chi-square test), with evidence of intense and uniform staining in a majority of U-CH1 tumor sections (score of 3) and more than half of the DVC-4 tumor sections (scores of 2–3). In contrast, a majority of sections from U-CH2b cells stained modestly for CD24 (scores of 1–2) with a predominantly heterogeneous staining pattern. Conclusions This is the first report on xenografts generated from U-CH2b cells in which a low tumorigenicity was discovered despite evidence of chordoma-like characteristics in vitro. For tumors derived from a primary chordoma cell and U-CH1 cell line, similarly intense staining for CD24 was observed, which may correspond to their similar potential to grow tumors. In contrast, U-CH2b tumors stained less intensely for CD24. These results emphasize that many markers, including CD24, may be useful in distinguishing among chordoma cell types and their tumorigenicity in vivo.

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Grieselhuber, Nicole R., Shaneice R. Mitchell, Shelley Orwick, Bonnie K. Harrington, Virginia M. Goettl, Alison R. Walker, Bhavana Bhatnagar et al. "The Novel BET Inhibitor PLX51107 Has In Vitro and In Vivo Activity Against Acute Myeloid Leukemia". Blood 128, n.º 22 (2 de diciembre de 2016): 3941. http://dx.doi.org/10.1182/blood.v128.22.3941.3941.

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Abstract Background: Acute myeloid leukemia (AML) has very poor long-term survival with traditional therapies. AML has a diverse pathogenesis and likely represents multiple different diseases. Various epigenetic effector proteins are altered in AML by mutation, over-expression, or compartmental displacement and these changes maintain transcriptional programs important for leukemogenesis. The bromodomain and extra-terminal domain (BET) proteins, including BRD2, BRD3 and BRD4, play roles in many cellular functions important to leukemogenesis, such as super-enhancer function, transcriptional elongation, histone acetylation and cell cycle progression. In particular, AML cells depend on BRD4 for expression of the pro-survival proteins MYC and BCL2. BRD4 has therefore become an attractive target for novel therapeutics. PLX51107 is a novel BET inhibitor with a unique binding mode in the acetylated lysine binding pocket of BRD4 that differentiates it from other compounds under investigation. Our group has previously shown this compound to have antineoplastic activity in models of aggressive B cell malignancies. We have now investigated the anti-leukemic properties of PLX51107 in both in vitro and in vivo models of AML. Results: PLX51107 treatment potently reduced viability and proliferation of the human AML cell lines MV4-11, MOLM-13, OCI-AML3, and Kasumi-1, with IC50 of 0.17, 1.8, 0.2 and 0.2 μM, respectively. We then evaluated the in vitro activity of PLX51007 in primary human AML samples. PLX51107 inhibited the proliferation of primary human AML cells co-cultured with HS5 stromal cells. For nearly all samples tested (n=9), the IC50 of PLX51007 was less than 1 μM (average = 0.41 μM, range 0.039 - 1.5 μM). Notably, PLX51107 showed efficacy across a broad range of AML risk groups, including samples with adverse risk features such as 11q23 abnormalities and FLT3-ITD mutations. In comparison, for the same AML samples, the average IC50 for JQ1 was 0.71 μM (range 0.02 - 3.3 μM) and for cytarabine was 3.5 μM (range 0.33 to >10 μM). Furthermore, PLX51107 treatment reduced the clonogenicity of primary AML cells. Following incubation of AML cells in 1 μM PLX51107, there was significantly decreased colony formation (p<0.05) in drug-free, cytokine-supplemented methylcellulose media. We next examined the efficacy of PLX51107 in vivo, utilizing luciferase labeled MV4-11 AML cells xenotransplanted into NOD / SCID / IL2rgnull (NSG) immunodeficient mice. Daily oral dosing with 20 mg/kg PLX51107 resulted in prolonged survival (median 47 days) compared to vehicle treated control animals (median 30 days, p< 0.001). Weekly measurement of bioluminescence showed decreased disease burden in PLX51107 treated mice. In addition, human peripheral blood CD45 / CD33 double positive cells were significantly decreased in treated animals. Histologic analysis conducted at day 16 showed decreased leukemic burden in the bone marrow of the PLX51107 treated animals. In addition, examination of tissues from moribund mice at time of euthanasia demonstrated fewer leukemia cells in the spleen, liver and bone marrow. Conclusions: Collectively, our results show pre-clinical activity of PLX51107 in AML, supporting further development of this compound in clinical trials for relapsed or refractory myeloid malignancies. We are currently working to define downstream targets of PLX51107 action and developing patient derived AML xenografts to further characterize the in vivo effects of PLX51107. Disclosures Walker: Gilead Sciences: Research Funding. Bhatnagar:Karyopharm: Research Funding.

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Huang, Yulun, Lin Qi, Mari Kogiso, Yuchen Du, Frank Braun, Huiyuan Zhang, Lei Huang et al. "PDTM-17. MiR-126, miR-369-5p AND miR-487b DRIVE PEDIATRIC GLIOBLASTOMA INVASION VIA KCNA1". Neuro-Oncology 21, Supplement_6 (noviembre de 2019): vi190—vi191. http://dx.doi.org/10.1093/neuonc/noz175.793.

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Abstract Diffuse invasion is one of the key features that make GBM particularly difficult to treat. We hypothesize that direct comparison of matched invasive (GBMINV) and tumor core GBM cells (GBMTC) would facilitate the discovery of drivers of pediatric GBM (pGBM) invasion. However, GBMINV cells are extremely difficult to obtain from normal brain tissues because aggressive surgical resection of normal tissue carries the risk of serious neurological deficits. Most past and current studies on GBM invasion were and are forced to utilize the resected primary tumor masses. To overcome this barrier, we utilized a panel of 6 pediatric patient tumor-derived orthotopic xenograft (PDOX) mouse models to isolate matching pairs of GBMTC cells and GBMINV cells and confirmed a significantly elevated invasive capacity in GBMINV cells both in vitro and in vivo. Global profiling of 768 human microRNA using a real-time PCR-based Taqman system identified 23 microRNAs were upregulated in the GBMINV cells in at least 4 of the 6 pGBM models as compared with the matching GBMTC cells. We subsequently showed that silencing the top three miRNAINV, miR-126, miR-369-5p, and miR-487b, suppressed tumor cell migration in vitro (both as neurospheres and monolayer cultures) without affecting cell proliferation, and blocked pGBM invasion in mouse brains. Integrated analysis of the mRNA profiling of the same set of GBMTC and GBMINV cells revealed the affected signaling pathways and identified KCNA1 as the sole common computational target gene of the three miRNAINV. Treatment of three pairs of GBMTC and GBMINV cells with two KCNA1 inhibitors, ADWX1 and Agitoxin 2, caused significant suppression of pGBM cell migration in vitro. In conclusion, this study revealed an intrinsically elevated invasive phenotype in GBMINV cells, identified miR-126, -369-5p, and -487b as novel drivers of pGBM invasion, and characterized KCNA1 as a potential therapeutic target for arresting pGBM invasion.

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Kuo, Tzu-Yun, Aisha Hasan y Richard J. O'Reilly. "A Comparison of Human CMVpp65-Specific Central Memory and Effector Memory CD8 T-Cells When Stimulated in-Vivo with IL-2 or IL-15/IL-15Rα Complex in a Murine Xenograft Model of Adoptive Cell Therapy". Blood 124, n.º 21 (6 de diciembre de 2014): 4805. http://dx.doi.org/10.1182/blood.v124.21.4805.4805.

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Abstract Initial clinical trials of adoptive immunotherapy have shown that the efficacy of adoptively transferred T-cells in man is often limited by the failure of cultured T cells, particularly cloned CD8 T cells, to persist in vivo. These studies demonstrated that the transferred T cells induced only transient responses and that persistence of the transferred T-cell clonotypes correlated with disease regression. A previous study suggested that CMV virus-specific CD8 T cell clones derived from central memory T cells (TCM), but not effector memory T cells (TEM), persisted long-term in non-human primates. On the other hand, another study comparing TCM and TEM derived SIV virus specific CD8 T-cell clones that were adoptively transferred in non-human primates demonstrated limited persistence of both TCM and TEM derived transferred T cells, and failed to show any difference between the two cell types. Because of these conflicting data, we have reexamed the persistence of adoptively transferred viral antigen specific T-cells derived from TCM and TEM population. Accordingly, we developed a NOG mouse model for studying the ability of human CMVpp65-specific T cells derived from central memory and effector memory populations to migrate to and accumulate in human tumor xenografts expressing CMVpp65, to alter the growth of these tumors and to persist in the tumors. This model also allows us to test immunomodulating agents and their ability to enhance targeted T-cell accumulations, antitumor activity and persistence. We analyzed CMVpp65-specific CD8 T cells derived from TCM and TEM precursors in vitro and in vivo. To tract the T-cells in vivo, we transduced membrane-bound Gaussia luciferase into TCM and TEM populations and monitored T cell trafficking by in vivo bioluminescence. Contrary to expectation, our results initially showed no differences between TCM and TEM derived CMVpp65-specific T-cell in mice co-treated with IL-2 in the time to accumulation, ultimate level of accumulation, degree of CMVpp65+ tumor regression or T-cell persistence. However, in mice cotreated with IL-15/IL-15Rα complex, both TCM and TEM exhibited more sustained engraftment and more prolonged accumulation in both the targeted tumor and in the marrow. In mice treated with IL-15/IL-15Rα, TCM and TEM derived T cells showed a similar effector memory phenotype and a similar level of regression of tumor growth. Thus, adoptive transfer of CMVpp65 specific TCM or TEM when combined with IL-15/IL-15Rα complex may support better persistence of antigen-specific T-cells following adoptive immunotherapy. Studies comparing IL-15/IL-15Rα complex with IL-15 alone are in progress. Disclosures No relevant conflicts of interest to declare.

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Zhu, Huang, Robert Blum, Zhengming Wu, Andres Bahena, Hanna Julie Hoel, Eivind Heggernes Ask, Kun-Liang Guan, Karl-Johan Malmberg y Dan S. Kaufman. "Notch Activation Rescues Exhaustion in CISH-Deleted Human iPSC-Derived Natural Killer Cells to Promote In Vivo Persistence and Enhance Anti-Tumor Activity". Blood 132, Supplement 1 (29 de noviembre de 2018): 1279. http://dx.doi.org/10.1182/blood-2018-99-112791.

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Abstract Cytokine-inducible SH2-containing protein (CIS) is a critical negative regulator of IL-15 signaling in natural killer (NK) cells and is encoded by CISH gene in human. Recent studies in a murine model demonstrate that CIS is a potent inhibitory checkpoint in NK cell-mediated tumor immunity. However, it is unclear if CIS similarly regulates human NK cell-mediated anti-tumor activity. Unlike CTLA-4 and PD1 that are expressed at the cell surface and can be blocked by antibody-mediated therapy, CIS is expressed intracellularly. Therefore, we deleted CISH gene in human induced pluripotent stem cells (iPSCS) using CRISPR/Cas9 technology and characterized the CISH-knockout iPSC lines. Our study demonstrates that CISH does not regulate maintenance of undifferentiated human pluripotent stem cells. We then derived NK cells from these gene-modified iPSCs using a two-stage in vitro hematopoietic-lymphoid differentiation protocol developed by our group. Initial hematopoietic differentiation of the iPSCs was unaffected by CISH deletion. However, deletion of CISH in iPSCs markedly delayed the second stage of in vitro NK cell differentiation. Specifically, whereas NK cell differentiation was typically fully complete with >90% NK cells after 4 weeks using WT iPSCs, the CISH-/- iPSC- cells only produced ~10% CD45+CD56+ NK cells at 4 weeks, though by 5 weeks these cultures were >80% NK cells. The CISH-/- iPSC-derived NK cells demonstrated typical NK surface maker expression, including CD94, CD16, NKG2D, NKp44, NKp46, FasL, and KIRs. Initial studies demonstrated that CISH-/- human iPSC-derived NK cells had significantly reduced ability to expand in vitro with evidence of NK cell exhaustion, including increased TIM-3 expression, decreased IFN-γ production and decreased cytotoxicity. RNA-seq analysis also confirmed that expression of exhaustion-related genes, including TIM3, CTLA4, and 2B4, were all significantly increased in CISH-/- NK cells. Interestingly, mass cytometric (CyTOF) analysis of CISH-/- NK cells with a panel of 36 phenotypic and functional NK cell markers identified an exhausted sub-population (increased expression of exhaustion marker TIM3 and inhibitory receptors such as ILT2 and Siglec7, as well as decreased proliferation marker Ki67). Importantly, this exhaustion could be rescued by co-culturing CISH-/- NK cells with Notch ligand-expressing OP9-DL4 stromal cells, leading to production of fully functionally mature NK cells. The CISH-/- NK cells stimulated by Notch maintained better expansion and improved cytotoxic function with low concentrations of either IL15 or IL2 compared to WT-iPSC-derived NK cells. CISH-/- NK cells demonstrate increased cytotoxic activity against leukemia cell lines K562 and MOLM-13 cells in vitro. Moreover, single-cell cytokine response analysis of CISH-/- NK cells after Notch stimulation showed >10 fold enrichment of polyfunctional cell subsets with effector cytokine production (Granzyme B, IFN-γ, MIP-1α, Perforin, TNF-α) compared with WT NK cells or NK cells from peripheral blood. In a MOLM-13 xenograft model, CISH-/- NK cells displayed significantly increased persistence in peripheral blood in comparison with WT NK cells (CISH-/- NK cells 6.81 ± 0.85 % vs WT NK cells 2.05 ± 0.25 N=5). More importantly, CISH-/- NK cells show significantly better control of tumor progression in the MOLM-13 xenograft model compared with WT NK cells. Together, these studies demonstrate CISH plays a key role to regulate NK cell activation-induced exhaustion and that Notch activation prevents this exhaustion to enable production of functionally hyperactive NK cells. Disclosures Guan: Vivace: Equity Ownership. Malmberg:Fate Therapeutics Inc.: Consultancy, Research Funding. Kaufman:Fate Therapeutics: Consultancy, Research Funding.

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Rossi, Randall M., Marlene Balys, Dean Franklin, Valerie Grose, Richard I. Fisher y Craig Jordan. "Inhibition of Human Lymphoma Cell Growth by the PKC-Beta Selective Inhibitor Enzastaurin (LY317615) in Combination with Multiple Therapeutic Agents." Blood 112, n.º 11 (16 de noviembre de 2008): 1595. http://dx.doi.org/10.1182/blood.v112.11.1595.1595.

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Abstract Previous studies in our lab have shown that the PKC-beta inhibitor, enzastaurin (LY317615), when used to treat a panel of human diffuse large cell lymphoma (DLCL) lines, was able to induce cell death in vitro and substantially reduce tumor growth in xenograft assays. These findings support the hypothesis that activation of PKC contributes to tumor cell survival and proliferation, which has been implicated in the pathogenesis of human B cell lymphomas. Specifically, PKC-beta activation is increased in tumor cells from patients with poor prognosis DLCL, suggesting that PKC-beta may be a target for therapeutic intervention. In the present study, we have explored the interaction of enzastaurin with a panel of well characterized therapeutic agents to evaluate whether its anti-tumor activity can potentially be enhanced. Drugs were chosen for analysis based either on known single agent activity in lymphoma, or by preclinical evaluation indicating potential synergy with enzastaurin. For in vitro culture assays (48–72 hr treatment), the addition of gemcitabine, rapamycin, or bortezomib, increased the cytotoxicity of enzastaurin from 2 to 7 fold. This effect was evident with multiple human DLCL cell lines, (OCI-Ly3, 7, 10, 19, and SUDHL-4, and 6), as well as two independent primary DLCL cultures. For in vivo studies, subcutaneous transplantation of the DLCL cell line OCI-Ly19, (previously engineered to express luciferase which allows for real time in vivo imaging), or a primary DLCL isolate, into immune deficient NOD/SCID mice formed reproducible tumors. Recipient animals were separated into uniform cohorts when the tumors were of <=500 cubic mm in size. The animals were then simultaneously or sequentially treated with enzastaurin, (150 mg/kg b.i.d. via oral gavage) and a secondary drug, either gemcitabine, (2.5 or 5.0 mg/kg 1x/3 days IP), bortezomib, (0.4 mg/kg twice weekly IP), rapamycin, (1.0 mg/kg, daily IP), or rituxan, (5 mg/kg, weekly IP). Imaging and analysis of tumor volumes showed that addition of either rituxan or rapamycin provided no additional benefit in comparison to enzastaurin alone during the course of treatment. In contrast, the combination of either gemcitabine or bortezomib with enzastaurin demonstrated significantly reduced tumor volumes in comparison to enzastaurin alone (17% to 38% greater decrease with enzastaurin + gemcitabine, and 50% greater decrease in tumor volume with enzastaurin + bortezomib). These data suggest that the use of enzastaurin in combination with existing therapeutic drugs (gemcitabine or bortezomib) has the potential to limit tumor size/growth while lowering dose levels and thereby reducing potential side effects associated with traditional treatments.

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Singh, Sanjay, Maxime Munyeshyaka, Joy Gumin, Jing Yang, Daniel Ledbetter, Anwar Hossain, Brittany Parker Kerrigan y Frederick Lang. "TAMI-24. BEHAVIOR OF GLIOBLASTOMA STEM-LIKE CELLS WITH KNOWN IDH1 STATUS IN CEREBRAL ORGANOIDS". Neuro-Oncology 22, Supplement_2 (noviembre de 2020): ii218. http://dx.doi.org/10.1093/neuonc/noaa215.913.

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Abstract Glioblastomas (GBM) exhibit high proliferative index, areas of necrosis, high vascularization, and are highly invasive to normal brain tissues. The most common and lethal form of GBMs are primary GBMs, with no prior clinical history. Whereas, secondary GBMs arise from low-grade gliomas and are associated with IDH1 mutation. Pre-clinical studies of GBM largely depend on patient-derived GBM stem-like cells (GSCs) in vitro and in vivo as orthotopic xenografts. Cerebral organoids (COs) derived from induced pluripotent stem cells can serve as allogenic in vitro model systems to study interactions between normal brain and GSCs. COs have been shown to harbor neural stem cells and their differentiated progenies as well as microglia within distinct niches. Here, we co-cultured 45 day-old COs and MDA-GSCs lines representing mesenchymal sub-group (M-MDA-GSC), classical sub-group (C-MDA-GSC), and IDH1 mutant (IDH1R132H-MDA-GSC). MDA-GSCs stably express fluorescent proteins and is used to track GSCs within COs. These GSC bearing COs were fixed, embedded, sectioned, immuno-stained, and imaged by confocal microscope. There was a positive correlation between GSC numbers in allografted niche and invasion into COs as measured from the edge of organoid, M-MDA-GSC (R2=0.99; 0.89μm/cell), C-MDA-GSC (R2=0.92; 0.66μm/cell), and IDH1R132H-MDA-GSC (R2=0.89; 0.5μm/cell). Additionally, M-MDA-GSCs had significantly high percentage of Ki67+ve invasive cells (24%) in comparison to C-MDA-GSCs (5.1%; p=0.0057). As a measure of interaction of MDA-GSC with normal cells, we assessed proximity of IBA1+ve microglia in GSC niche within organoids and show that M-MDA-GSC and IDH1R132H-MDA-GSC highly co-localized with IBA1+ve microglia on day12 of co-culture. In conclusion, our cerebral organoid-based allograft study shows that mesenchymal GSCs (M-MDA-GSC) are most invasive whereas IDH1 mutant GSCs (IDH1R132H-MDA-GSC) are least invasive. C-MDA-GSCs are least proliferative while invading into normal COs. Uniqueness of CO based allograft system is highlighted by observed similarity between M-MDA-GSC and IDH1R132H-MDA-GSC for their potential to attract IBA1+ve microglia.

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Gibson, Amber, Mao Zhang, Pariya Sukhumalchandra, Anne V. Philips, Na Qiao, Alexander A. Perakis, Celine Kerros et al. "Pembrolizumab in Combination with Antigen-Specific Cytotoxic T Lymphocytes Enhances Killing of Acute Myeloid Leukemia". Blood 138, Supplement 1 (5 de noviembre de 2021): 2775. http://dx.doi.org/10.1182/blood-2021-149318.

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Abstract Background Pembrolizumab, an antibody that blocks programmed cell death protein 1 (PD-1), has been FDA approved for several solid tumors and hematologic malignancies. Currently, pembrolizumab is under investigation for acute myeloid leukemia (AML) in combination with hypomethylating agents. It is established that AML is highly responsive to immunotherapy, as seen with the anti-leukemic effect of allogeneic hematopoietic stem cell transplantation (alloHSCT). However, response to cytotoxic T lymphocytes (CTLs) that target leukemia-associated antigens (LAAs) has been less reliable in eradicating disease. This insufficient response to LAA-specific CTLs is likely partially accounted for by the immune dysregulation seen in AML. Because of promising murine data that blockade of the PD1/PD-L1 pathway enhances the graft versus leukemia effect of alloHSCT, we investigated if adding pembrolizumab to CTLs that target the two LAAs CG1 and PR1 will enhance CTL antileukemia activities. CG1 and PR1are two HLA-A2 restricted nonameric peptides that we validated as promising AML targets derived from cathepsin G (i.e. CG1), and proteinase 3 (P3) and neutrophil elastase (NE) (i.e. PR1). We hypothesized that pembrolizumab added to CG1-CTLs and PR1-CTLs, will enhance their anti-leukemic effects with minimal off target toxicities. Methods Using a standard calcein AM in vitro cytotoxicity assay, we co-cultured AML targets, including U937 HLA-A2 + (U937-A2) AML cell line and primary patient HLA-A2 + AML samples, with CG1-CTL and PR1-CTL. AML cells were loaded with calcein AM and then incubated with CG1- and PR1-CTLs at increasing effector to target ratios. Pembrolizumab or isotype antibody were added to the cultures. After 4 hours, calcein AM was measured to determine cell viability. T2 cells pulsed with PR1 or CG1, were used as a positive control and non-pulsed T2 cells were used as negative control cells. For in vivo experiments, we used a human established AML xenograft mouse treatment model to determine the effect of pembrolizumab when added to CG1- or PR1- CTL in vivo. CG1-CTL and PR1-CTLs were expanded from the same donor and used as the effector cells. NOD/SCID gamma (NSG) mice (4-6-week-old females) were engrafted with AML samples by tail vein injection. After confirming engraftment, CG1- and/or PR1-CTL were administered to mice and pembrolizumab or isotype antibody [100ug/mouse] were given three times over two weeks. Mice were monitored for clinical GVHD and AML three times/week. Mice were sacrificed at approximately two weeks following treatment. To assess for GVHD, mouse tissues including spleen, liver, kidney, BM, intestine, brain, heart, and lung were harvested and fixed in 10% formalin. The fixed tissue samples were embedded in paraffin, sectioned, and stained with hematoxylin and eosin prior to histologic examination. Bone marrow (BM) was processed using standard methodology and analyzed for residual AML by flow cytometry. Results: In vitro our data demonstrate that U937-A2 and two primary patient HLA-A2 AML samples, have enhanced cell lysis when treated with pembrolizumab (CTL+ pembrolizumab) in comparison with isotype (Iso) + CTL, pembrolizumab only, iso only or CTL only groups (Figure 1). In vivo data show a decrease in U937-A2 disease burden and primary patient AML after treatment with CG1and/or PR1-CTL (CTL-treated) . This decrease was enhanced when pembrolizumab was added to the CTL-treated mice (CTL+ pembrolizumab) in comparison with mice treated with pembrolizumab only (pembrolizumab-treated), or CTL only (CTL-treated) (Figure 2). Pathology data to assess toxicity in mice treated with CTL +/- pembrolizumab showed an enhanced pulmonary (perivascular and parabronchial) lymphocytic infiltration in mice treated with the combination of CTL and pembrolizumab. The other organs investigated, showed no change when combination therapy was used. Conclusion: We have validated in vitro and in vivo the enhanced killing of AML (cell lines and primary patient samples) by CG1-CTL and/or PR1-CTL after addition of pembrolizumab. Toxicity data show mild enhancement of lymphocytic infiltrate in the lungs after addition of pembrolizumab to CTL. Our data suggest that the strategy of combining LAA-specific CTL with immune checkpoint blockade could prove beneficial in the setting of adoptive T cell therapy and allogeneic stem cell transplantation for AML. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

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Wu, Christina C. N., Fitzgerald Lao, Hongying Li, Laura Rassenti, Thomas J. Kipps, Karen Messer, Dennis A. Carson y Michael Y. Choi. "Inhibition of Wnt Signaling By Dimethyl Fumarate Results in in Vitro and in Vivo Clearance of Chronic Lymphocytic Leukemia Cells and Has Additive Activity with Ibrutinib". Blood 124, n.º 21 (6 de diciembre de 2014): 4683. http://dx.doi.org/10.1182/blood.v124.21.4683.4683.

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Abstract Background: Small molecules that inhibit B cell survival pathways are effective treatments for patients with chronic lymphocytic leukemia (CLL). However, such therapies are not curative, and resistance can develop in some patients. Combination therapies with agents that inhibit several CLL survival pathways may allow for more complete responses, and help prevent treatment resistance. Previous data has shown that the pro-survival Wnt pathway is highly active in CLL and is a negative prognostic factor, and therefore is an attractive target for novel therapies to combine with agents like ibrutinib. Dimethyl fumarate (DMF) is an orally bioavailable fumaric acid ester with immunomodulatory properties, including inhibition of the NF-kB signaling cascade. DMF has been evaluated as a systemic treatment of psoriasis as well as multiple sclerosis. Our group previously observed anti-CLL effects of DMF, mediated in part through oxidative stress. Herein we describe a novel mechanism of action of DMF and ibrutinib, mediated by inhibition of the Wnt signaling pathway. Methods: Effects of DMF and ibrutinib on Wnt signaling were determined using a cell-based LEF/TCF beta-lactamase reporter gene FRET assay. In vitro activity was assessed in primary CLL from patients with indolent and aggressive disease. In vivo activity was evaluated in Rag2-/- gamma chain-/- immunodeficient (RG-KO) mice, which were engrafted with human CLL cells by intraperitoneal injection. DMF and/or ibrutinib were administrated to mice by oral gavage, at clinically used doses and schedules. Results: Both DMF and ibrutinib have an alpha-beta unsaturated ketone that can react with essential free cysteines in the Wnt-driven LEF1 transcription factor. This effect was confirmed by a cell-based reporter gene assay in which DMF inhibited LEF/TCF dependent gene expression at low μM levels. Ibrutinib also inhibited Wnt signaling activity in the same assay. In short term cultures, DMF was cytotoxic to primary CLL cells from patients with both indolent and aggressive disease, at low uM concentrations. The combination of DMF and ibrutinib resulted in a higher degree of CLL cell clearance than achieved by either agent alone (p < 0.05 after multiple comparison adjustments, Dunnet’s method). To evaluate the effect in a preclinical CLL xenograft animal model, we administered DMF by oral lavage to RG-KO mice engrafted with human CLL cells. Doses ranging from 3 to 30 mg/kg BID for 7 days resulted in dose dependent clearance of CLL cells compared to vehicle controls, without observable toxicity to the recipient animals. Moreover, the combination of DMF and ibrutinib resulted in a higher degree of CLL cell clearance than achieved by either agent alone. Preliminary FACS analyses revealed that DMF selectively targets CLL subpopulations of cells with aggressive characteristics, as assessed by CD38 expression. Further molecular analyses of predictive or correlative biomarkers are ongoing. Conclusions: DMF inhibits Wnt signaling, and has single agent activity as a treatment for CLL. The combination of DMF and ibrutinib is more effective than either agent alone, particularly in aggressive disease, and is well tolerated. Clinical trials of DMF in CLL are warranted, and are planned. This work is supported by a Leukemia and Lymphoma Society Specialized Center of Research Grant (7005-14) and by the CLL Research Consortium (5P01CA081534-14). Disclosures No relevant conflicts of interest to declare.

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Sison, Edward Allan R., Daniel Magoon, Eric Chevalier, Klaus Dembowsky y Patrick Brown. "The Novel CXCR4 Antagonist POL5551 Decreases Surface CXCR4 (s-CXCR4) Expression, Inhibits Chemotaxis, and Enhances Chemosensitivity in Acute Lymphoblastic Leukemia (ALL)". Blood 120, n.º 21 (16 de noviembre de 2012): 780. http://dx.doi.org/10.1182/blood.v120.21.780.780.

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Abstract Abstract 780 Background: The interaction between the cell surface receptor CXCR4 and the chemokine SDF-1 (CXCL12) is critical in signaling between leukemic blasts and the bone marrow microenvironment. We previously demonstrated that CXCR4 is an important mediator of chemotherapy resistance, as chemotherapy-induced upregulation of s-CXCR4 in acute myeloid leukemia (AML) cell lines and primary samples led to increased SDF-1-mediated chemotaxis and increased protection by normal human bone marrow stroma from chemotherapy-induced apoptosis. We also showed that stromal protection and chemotherapy resistance could be reversed by treatment with the FDA-approved CXCR4 inhibitor plerixafor, both in vitro in stromal co-cultures of pre-B cell ALL cell lines and in vivo in xenografts of primary samples of infant MLL-rearranged ALL. Therefore, disruption of the CXCR4/SDF-1 axis is a rational means to target extrinsic survival mechanisms in acute leukemia. The novel Protein Epitope Mimetic (PEM) POL5551 is a selective and potent antagonist of CXCR4. Treatment with POL5551 inhibits vascular accumulation of CXCR4+ smooth muscle cells but its effects on ALL have not been reported. We hypothesized that treatment of ALL cell lines with POL5551 would 1) decrease s-CXCR4 expression, 2) inhibit SDF-1-mediated chemotaxis, and 3) reverse stromal-mediated protection from chemotherapy-induced apoptosis. Methods/Results: Pre-B cell ALL (697, HB11;19, NALM-6, SEMK2) and T cell ALL cell lines (CCRF-CEM-1301, Jurkat, Molt-4) were treated with dose ranges of POL5551. Cells were harvested at multiple time points over 72 hours and s-CXCR4 was measured by FACS. S-CXCR4 was potently and markedly reduced in all cell lines, with IC50 levels of <5 nM at 1 hour and IC50 levels of <20 nM at 48 hours. In comparison, 3- to 30-fold higher doses of plerixafor were needed to achieve similar levels of reduction. Simultaneous measurement of cell proliferation using the WST-1 proliferation assay demonstrated that treatment with POL5551 neither increased nor decreased leukemia cell proliferation in a significant manner. To ascertain the functionality of s-CXCR4 inhibition, we performed chemotaxis assays. Leukemia cells were treated with 10 nM POL5551 or vehicle control and placed into hanging cell culture inserts. Migration through a permeable membrane toward an SDF-1 gradient was then measured after 24 hours. Compared to control-treated cells, POL5551-treated cells had significantly decreased SDF-1-induced chemotaxis (average 38% reduction in chemotaxis in pre-B cell lines, p<0.001; average 41% reduction in T cell lines, p=0.05). We also performed co-culture experiments with normal human bone marrow stroma in the presence and absence of POL5551 to further demonstrate the functional effects of s-CXCR4 inhibition. Specifically, we cultured leukemia cells off stroma (O), on stroma (S), or pretreated with POL5551 for 30 minutes prior to plating on stroma (P+S). Cells from each culture condition were then treated with dose ranges of chemotherapy. Following treatment, we measured apoptosis by staining with Annexin V/7-AAD. IC10 through IC90 values were obtained using Calcusyn. To quantify stromal protection, we calculated a Protective Index (PI), defined as the S IC values divided by the O IC values. Thus, PI >1 signified stromal protection, while PI ≤1 signified no stromal protection. To quantify the ability of POL5551 to reverse stromal protection, we calculated a Reversal Index (RI), defined as the P+S IC values divided by the O IC values. Therefore, PI > RI indicated a decrease in stromal protection, while RI ≤1 indicated a reversal of stromal protection. Overall, stroma protected leukemia cells from chemotherapy-induced apoptosis. Importantly, treatment with POL5551 abrogated stromal-mediated protection and restored chemosensitivity (eg, PI 1.182 vs. RI 0.956 for NALM-6 treated with daunorubicin +/− 20 nM POL5551, p<1×10e-9). Conclusions: The novel CXCR4 antagonist POL5551 is a potent inhibitor of CXCR4 in pre-B and T ALL cell lines with activity at nanomolar concentrations in decreasing s-CXCR4 expression, inhibiting SDF-1-induced chemotaxis, and reversing stromal-mediated protection from chemotherapy in vitro. Therefore, if our findings are confirmed in primary samples and in vivo, interruption of leukemia-microenvironment signaling with POL5551 may prove to be an effective strategy in the treatment of pre-B and T cell ALL. Disclosures: Chevalier: Polyphor Ltd: Employment. Dembowsky:Polyphor Ltd: Employment.

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Bailey, Stefanie R., Sonika Vatsa, Rebecca Larson, Amanda A. Bouffard, Irene Scarfò, Kathleen M. E. Gallagher, Matthew J. Frigault y Marcela V. Maus. "Blocking IFNγ in CAR-T Reduces Checkpoint Inhibitors and Cell-Mediated Toxicity without Compromising Therapeutic Efficacy in CD19 +malignancies". Blood 138, Supplement 1 (5 de noviembre de 2021): 1723. http://dx.doi.org/10.1182/blood-2021-146042.

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Abstract Background: Chimeric antigen receptor T cells (CAR-T) induce impressive responses in patients with hematologic malignancies but can also mediate a systemic inflammatory toxicity known as cytokine release syndrome (CRS), marked by elevated levels of pro-inflammatory cytokines and chemokines released from activated CAR-T and innate immune cells. Release of the pro-inflammatory cytokine interferon-gamma (IFNγ) in response to antigen is used as a potency assay for CAR-T cells, but elevated levels have been identified in patients suffering from CAR-T-associated toxicities such as CRS and neurotoxicity. Mutations in IFNγ receptor signaling have been identified as a mechanism of resistance in checkpoint blockade in melanoma and other solid tumors, and we have recently identified that IFNγ receptor signaling also confers resistance to CAR-T cell mediated cytotoxicity in solid tumors, but its biologic role in conferring responses in hematologic malignancies is not established. Methods: CD19-targeted CAR-T were generated using either 4-1BB or CD28 costimulatory domains. CAR-T effector functions in vitro and in vivo were assessed in the presence of absence of IFNγ-blocking antibody. Furthermore, we used CRISPR/Cas9 editing to knock out IFNγ in CD19-directed CAR-T cells. The effects of IFNγ inhibition in CAR-T by pharmacologic and genetic approaches on T cell function, immune checkpoint inhibitor expression, cancer cell lysis and macrophage activation/phenotype were assessed using ELISA, flow cytometry, in vitro/in vivo tumor models and Luminex/fluorescence microscopy/NanoString, respectively. Finally, serum from B cell lymphoma patients treated with the CAR-T products tisagenlecleucel or axicabtagene ciloleucel was collected 3 days post-CAR infusion and added to human macrophages in vitro in the presence of blocking antibodies to IFNγ versus the current clinical agents for managing CRS, including those targeting IL-1Rα and IL-6R. Macrophage phenotype and function was determined using NanoString, ELISA, and immunofluorescence microscopy. Results: We found that pharmacologic blockade or genetic knockout of IFNγ specifically reduces IFNγ signaling without compromising T cell phenotype or effector function, including production of GM-CSF, IL-2, Granzyme B and TNFα. We also observed reduced expression of the immune checkpoint proteins CTLA-4, PD-1, Lag3 and Tim3, which correlated with enhanced antigen-specific CAR-T proliferation. Cytotoxicity assays and NSG xenograft tumor-bearing mouse models revealed that blocking IFNγ has no effect on therapeutic efficacy of CAR T cells against CD19 + leukemias or lymphomas in vitro or in vivo. Furthermore, pharmacologic blockade or genetic knockout of IFNγ in CD19-directed CAR T cells abrogated macrophage activation in vitro and in hybrid in vitro/in vivo models of CRS, as shown by a reduction of activation markers (CD69, CD86) and pro-inflammatory proteins (IL-6, IP-10, MIP-1β and MCP-1). Further interrogation revealed that these findings were IFNγ-dependent but cell contact-independent. Finally, data herein reveals that blocking IFNγ in both healthy donor CAR-T cultures and lymphoma patient serum results in reduced macrophage activation/function to a similar, if not superior, extent as current clinical approaches targeting IL-1Rα and IL-6R. In addition to reduced macrophage function, NanoString analysis revealed a decreased expression of immune checkpoint inhibitor genes HAVCR2, VSIR and PDCD1LG2 and upregulation of co-stimulatory genes DPP4 and ICOSL. Conclusions: Collectively, these data show that IFNγ is dispensable for the efficacy of CAR-T against hematologic malignancies and blocking IFNγ could simultaneously mitigate cytokine-related toxicities while enhancing T cell proliferation and persistence via reduced expression of immune checkpoint proteins. Furthermore, direct comparison of IFNγ blockade or knockout in the CAR T cell product with current clinical strategies suggests that targeting IFNγ could mitigate major cytokine-related toxicities to a greater extent than existing approaches. Disclosures Frigault: Arcellx: Consultancy; Novartis: Consultancy, Research Funding; Kite: Consultancy, Research Funding; BMS: Consultancy; Iovance: Consultancy; Takeda: Consultancy; Editas: Consultancy. Maus: WindMIL: Consultancy; Torque: Consultancy, Current holder of stock options in a privately-held company; Tmunity: Consultancy; Novartis: Consultancy; Micromedicine: Consultancy, Current holder of stock options in a privately-held company; Kite Pharma: Consultancy, Research Funding; GSK: Consultancy; Intellia: Consultancy; In8bio (SAB): Consultancy; CRISPR therapeutics: Consultancy; Cabaletta Bio (SAB): Consultancy; BMS: Consultancy; Bayer: Consultancy; Atara: Consultancy; AstraZeneca: Consultancy; Astellas: Consultancy; Arcellx: Consultancy; Agenus: Consultancy; Adaptimmune: Consultancy; tcr2: Consultancy, Divested equity in a private or publicly-traded company in the past 24 months; century: Current equity holder in publicly-traded company; ichnos biosciences: Consultancy, Current holder of stock options in a privately-held company.

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19

Ruella, Marco, Saad S. Kenderian, Olga Shestova, Joseph A. Fraietta, Sohail Qayyum, Qian Zhang, Marcela V. Maus et al. "The Addition of the BTK Inhibitor Ibrutinib to Anti-CD19 Chimeric Antigen Receptor T Cells (CART19) Improves Engraftment and Antitumor Responses Against Mantle Cell Lymphoma". Blood 126, n.º 23 (3 de diciembre de 2015): 704. http://dx.doi.org/10.1182/blood.v126.23.704.704.

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Abstract Introduction: The bruton tyrosine kinase (BTK) inhibitor ibrutinib demonstrates considerable activity in mantle cell lymphoma (MCL). However, approximately 30% of patients do not respond to this treatment and the therapy invariably leads to drug resistance with a median response of 17.5 months. Infusion of autologous T cells transduced with chimeric antigen receptors (CAR) against the B-cell specific CD19 antigen (CART19) leads to dramatic clinical responses in the majority of patients with acute lymphoblastic leukemia and the activity in B cell lymphoma is currently being evaluated in clinical trials. Bulky disease, as sometimes seen in MCL, may impair T cell infiltration. The features of ibrutinib that make it an interesting addition to CART19 include its efficacy in reducing tumor masses and its ability to mobilize neoplastic B cells into the peripheral blood, thereby potentially exposing them to the killing activity of CART19. Therefore, we sought to investigate the combination of the two novel targeted therapies, ibrutinib and CART19 in MCL. Results: In vitro studies with established MCL cell lines and with a novel cell line (MCL-RL) showed a range of responses to ibrutinib with an IC50 ranging from 10 nM to 10 µM; MCL-RL was the most sensitive cell line evaluated with an IC50 of 10nM, similar to primary MCL. Both ibrutinib-sensitive and ibrutinib-resistant cell lines strongly activated CART19 in an antigen-specific manner as detected by CD107a degranulation, cytokine production and CFSE proliferation assays. Importantly, in vitro assays with MCL cell lines co-cultured with increasing doses of CART19 (E:T= 2:1, 1:1, 0.5:1, 0.25:1) combined with increasing concentrations of ibrutinib (0, 10, 100, 1000 nM) demonstrated strong additive tumor killing (Figure 1). Notably, supra-therapeutic doses of Ibrutinib (>/=1 uM) impaired cytokine production and T cell proliferation in vitro. In order to test this combination in vivo we established a novel MCL model, injecting i.v. luciferase-positive MCL-RL cells into NSG mice. This resulted in 100% MCL engraftment in liver and spleen, with eventual dissemination into lymph nodes and bone marrow. Treatment with three different doses of CART19 (0.5, 1 and 2 million cells/mouse) led to a dose dependent anti-tumor effect. A similar dose response to CART19 was also observed in the ibrutinib-resistant Jeko-1 cell line. We also treated MCL-RL xenografts with different doses (0, 25 and 125 mg/Kg/day) of ibrutinib, with a median overall survival respectively of 70, 81 and 100 days (p<0.001). Importantly, a direct in vivo comparison of the highest ibrutinib dose (125 mg/kg) and CART19 showed a significantly improved tumor control for mice treated with CART19. However, treatment with either CART19 or ibrutinib as single agents invariably led to late relapse. Therefore we sought to treat MCL-RL xenografts with the combination of CART19 and ibrutinib and compare it to the single agent activity. The combination resulted in significant improvement in tumor control compared to mice treated with the single agents with 80% of mice achieving long-term disease-free survival ( p=0.007 at day 110, representative mice shown in Figure 2A). Intriguingly, we found that mice treated with ibrutinib had higher numbers of circulating CART19 cells (Figure 2B). Conclusions: Combining CART19 with ibrutinib represents a rational way to incorporate two of the most recent therapies in MCL. Our findings pave the way to a two-pronged therapeutic strategy in patients with MCL and other types of B-cell lymphoma. Figure 1. Figure 1. Figure 2. Figure 2. Disclosures Ruella: Novartis: Patents & Royalties, Research Funding. Kenderian:Novartis: Patents & Royalties, Research Funding. Maus:Novartis: Consultancy, Patents & Royalties, Research Funding. Milone:Novartis: Patents & Royalties, Research Funding. Lacey:Novartis: Patents & Royalties, Research Funding. Mato:Genentech: Consultancy; Pronai Pharmaceuticals: Research Funding; Celgene Corporation: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; Gilead: Consultancy, Research Funding; TG Therapeutics: Research Funding; AbbVie: Consultancy, Research Funding; Janssen: Consultancy. Schuster:Genentech: Consultancy; Pharmacyclics: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Hoffman-LaRoche: Research Funding; Janssen: Research Funding; Gilead: Research Funding; Nordic Nanovector: Membership on an entity's Board of Directors or advisory committees; Novartis: Research Funding. Kalos:Novartis: Patents & Royalties, Research Funding. June:Novartis: Research Funding; University of Pennsylvania: Patents & Royalties: financial interests due to intellectual property and patents in the field of cell and gene therapy. Conflicts of interest are managed in accordance with University of Pennsylvania policy and oversight. Gill:Novartis: Patents & Royalties, Research Funding. Wasik:Janseen and Novartis: Research Funding.

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Sanford, Dominic E., Andrew Giorgi, Brian D. Goetz, Roheena Z. Panni, William G. Hawkins, David Linehan, Peter S. Goedegebuure y Ryan C. Fields. "Demonstration of subpopulations with differing cancer stem cell phenotypes in xenograft and in vitro models of colorectal liver metastases." Journal of Clinical Oncology 31, n.º 4_suppl (1 de febrero de 2013): 394. http://dx.doi.org/10.1200/jco.2013.31.4_suppl.394.

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394 Background: Tumors are composed of heterogeneous cell populations, some of which demonstrate enhanced tumor-forming capabilities (so-called tumor initiating cells [TIC] or cancer stem cells). In colorectal cancer (CRC), CD133, 44, and 24 are cell surface markers that identify TIC. Therefore, we sought to determine if CRC liver metastases (CRC-LM) form xenografts (in vivo) and cell cultures (in vitro) with TIC markers. Methods: CRC-LM were grafted in NOD/SCID mice and passaged serially. Xenografts were mechanically dissociated and cultured under sphere forming conditions. Flow cytometry was performed for TIC phenotype. Results: 16 of 18 (89%) CRC-LM specimens formed tumors in mice. Xenografts formed EpCAM+ tumors and spheres. The frequency of CD133+, CD44+, and CD133+/CD44+ tumor cells were 55%, 33%, and 23%, respectively. There was a subpopulation of CD133+/CD44+ cells with elevated CD44 expression(CD44hi). This CD133+/CD44hi population was also CD24+; representing 5% of cells. Eight of eleven (73%) xenografts formed spheres in vitro. The frequency of CD133+, CD44+, and CD133+/CD44+ cells were 63%, 47%, and 26%, respectively. CD133+/CD44+/CD24+ cells made up 8% of sphere-forming cells. There was a non-significant trend towards increased frequency of CD133+, CD44+, and CD133/CD44 positive cells in the spheres compared to the xenografts. However, the percentage of CD133+/CD44+/CD24+ cells was significantly increased in spheres relative to xenografts (8% vs. 5%, respectively; p<0.05) (see Table). Conclusions: CRC-LM derived xenografts and spheres are composed of distinct cell populations with differing levels of TIC/cancer stem cells. Sphere cultures may enhance for the most enriched TIC population. Thus, xenografts and sphere cultures are important model systems to further study the importance of cancer stem cells in CRC progression and metastases. [Table: see text]

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Freiwan, Abdullah, Abishek Vaidya, Caitlin Zebley, Yiping Fan, Deanna Langfitt, Benjamin Youngblood, Maksim Mamonkin, Stephen Gottschalk y Mireya Paulina Velasquez. "Engineering Naturally Occurring CD7 Negative Cells for the Immunotherapy of CD7 Positive Leukemia". Blood 134, Supplement_1 (13 de noviembre de 2019): 868. http://dx.doi.org/10.1182/blood-2019-124903.

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Background: CD7 has emerged as a promising target for the adoptive immunotherapy with T-cells expressing chimeric antigen receptors (CAR T-cells) of CD7+ T-cell acute lymphoblastic leukemia (T-ALL) and acute myeloid leukemia (AML). However, expressing CD7 CARs in T-cells results in fratricide due to high expression of CD7 in most T-cells. While investigators have developed strategies to overcome this limitation by additional genetic modifications of CD7 CAR T-cells, the goal of this project was to explore the feasibility of selecting and genetically modifying naturally occurring CD7 negative (CD7-) T cells for the adoptive immunotherapy of CD7+ leukemia. Methods: CD7- T-cells were isolated from PBMCs using a 2-step magnetic bead depletion/selection procedure (CD7 depletion followed by selection of CD3+ T cells from the CD7- fraction). Non-selected T-cells (bulk T-cells), CD7+ and CD7- T cells were activated and transduced with a retroviral vector encoding a second-generation CD7 CAR with a CD28 costimulatory endodomain, and expanded with IL7 and IL15. The effector function of CD7- T-cells expressing CD7 CARs (CD7 CARCD7- T cells) was assessed in vitro as well as in xenograft models. Results: To assess the feasibility of our approach, we first determined the frequency of CD7- T-cells in PBMCs. On average, 4.7 % of T cells were CD7- (range: 2% - 12.3%; N=22), and we successfully selected these cells from bulk PBMCs with a combined CD7 depletion/CD3 selection procedure. We genetically modified CD7-, CD7+ and bulk T cellsto express CD7 CARs (CD7 CARCD7-, CD7 CARCD7+, CD7 CARBulk). Transduction efficiencies ranged from 31% to 75% (± 5%) for each T-cell population. Post transduction, CD7 CARCD7- T-cells did not undergo fratricide and had similar expansion kinetics (N=6, p=ns) in comparison to non-transduced (NT) T-cell cultures (NT CD7-, NT CD7+, NT bulk). In contrast, CD7 CARCD7+or CD7 CARBulk T-cells underwent fratricide and did not expand (N=6, p<0.0001). CD7- T-cells (NT and CD7 CARCD7-) had a predominantly CD4+ effector memory phenotype at day 7 and 14 of culture. To assess the effector function of CD7 CARCD7- T-cells, we co-cultured them with CD7+ T-ALL cell lines (CCRF, MOLT3). CD7 CARCD7- T-cells recognized CD7+ targets in contrast to CD7- targets (BV173, Daudi) as evidenced by significant (N=6, p<0.0001) IFN-γ and IL-2 production. Control CAR T-cells (CD19 CARCD7-) did not recognize CD7+ target cells, confirming specificity. CD7 CARCD7- T-cells also had potent cytolytic activity against CD7+ targets in cytotoxicity assays. To assess in vivo the anti-tumor activity of CD7 CARCD7- T-cells, we used a NSG mouse xenograft model with CCRF cells, genetically modified to express firefly luciferase (CCRF.ffluc) to allow for serial bioluminescence imaging. A single infusion of CD7 CARCD7- T-cells had potent anti-leukemia activity as judged by serial imaging resulting in a significant survival (p<0.003) advantage in comparison to control mice. Conclusion: We have successfully generated CD7 CARCD7- T-cells from peripheral blood CD7- T-cells. CD7 CARCD7- T-cells had a predominantly CD4+ effector memory phenotype, and potent anti-leukemia activity in vitro and in vivo. Thus, naturally occurring CD7- T cells may present a promising T-cell source for the cellular immunotherapy of CD7+ leukemia. Disclosures Langfitt: MBIO: Other: St. Jude Children's Research Hospital has an existing exclusive license and ongoing partnership with Mustang Bio for the further clinical development and commercialization of this XSCID gene therapy. Youngblood:MBIO: Other: St. Jude Children's Research Hospital has an existing exclusive license and ongoing partnership with Mustang Bio for the further clinical development and commercialization of this XSCID gene therapy. Gottschalk:NHLBI: Research Funding; America Lebanese Syrian Associated Charities: Research Funding; ASSISI fundation of Memphis: Research Funding; California Institute for Regenerative Medicine: Research Funding; ViraCyte: Consultancy; MBIO: Other: St. Jude Children's Research Hospital has an existing exclusive license and ongoing partnership with Mustang Bio for the further clinical development and commercialization of this XSCID gene therapy; Patents and patent applications in the fields of T-cell & Gene therapy for cancer: Patents & Royalties; TESSA Therapeutics: Other: Research Collaboration; Tidal: Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria; EMD Serono: Honoraria; Merck: Consultancy; Inmatics: Membership on an entity's Board of Directors or advisory committees. Velasquez:St. Jude: Patents & Royalties: Patent Applications in the Fields of Cell and Gene Therapy ; Rally! Foundation: Membership on an entity's Board of Directors or advisory committees.

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Wußmann, Maximiliane, Florian Kai Groeber-Becker, Sabrina Riedl, Dina Alihodzic, Daniel Padaric, Lisa Gerlitz, Alexander Stallinger, Bernadette Liegl-Atzwanger, Dagmar Zweytick y Beate Rinner. "In Model, In Vitro and In Vivo Killing Efficacy of Antitumor Peptide RDP22 on MUG-Mel2, a Patient Derived Cell Line of an Aggressive Melanoma Metastasis". Biomedicines 10, n.º 11 (17 de noviembre de 2022): 2961. http://dx.doi.org/10.3390/biomedicines10112961.

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The host defense derived peptide was assessed in different model systems with increasing complexity employing the highly aggressive NRAS mutated melanoma metastases cell line MUG-Mel2. Amongst others, fluorescence microscopy and spectroscopy, as well as cell death studies were applied for liposomal, 2D and 3D in vitro models including tumor spheroids without or within skin models and in vivo mouse xenografts. Summarized, MUG-Mel2 cells were shown to significantly expose the negatively charged lipid phosphatidylserine on their plasma membranes, showing they are successfully targeted by RDP22. The peptide was able to induce cell death in MUG-Mel2 2D and 3D cultures, where it was able to kill tumor cells even inside the core of tumor spheroids or inside a melanoma organotypic model. In vitro studies indicated cell death by apoptosis upon peptide treatment with an LC50 of 8.5 µM and seven-fold specificity for the melanoma cell line MUG-Mel2 over normal dermal fibroblasts. In vivo studies in mice xenografts revealed effective tumor regression upon intratumoral peptide injection, indicated by the strong clearance of pigmented tumor cells and tremendous reduction in tumor size and proliferation, which was determined histologically. The peptide RDP22 has clearly shown high potential against the melanoma cell line MUG-Mel2 in vitro and in vivo.

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Mikhaylova, I. N., E. M. Treshalina, L. F. Morozova, N. V. Andronova, I. Zh Shubina y A. A. Lushnikova. "Cell lines of human melanoma and their xenograft with braf or nras mutations a targets for targeted therapy. Reviews". Russian Journal of Biotherapy 17, n.º 4 (11 de enero de 2019): 27–35. http://dx.doi.org/10.17650/1726-9784-2018-17-4-27-35.

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The review presents a discussion on articles and patents, describing new in vitro and in vivo models of pigmented or non-pigmented human cutaneous melanoma, received in NMRCO from the patients» metastases. Molecular genetic characteristics of the new models is supported by the arguments in addition to the given data and visual materials. The subjects of the discussed publications are 3 polyclonal cell lines, 2 subclones and 4 subcutaneous (s/c) xenografts in immunodeficient mice Balb/c nude. All the models are stored in Cryo Collection with xenografts at N.N. Blokhin NMRCO as well as in the Russian Collection of Cell Cultures of Vertebrae (RCCCV, St. Petersburg). This mini-collection is recommended for use in basic research of cutaneous melanoma and pre-clinical studies of anti-melanoma agents. The basis for these studies are the appropriate characteristics of the models, including cytological, immunologic, transplantation and molecular-genetic ones, as well as in vivo drug sensitivity to the corresponding target therapy.

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Xu, Xiaoxi, Rajendra Kumari, Jun Zhou, Jing Chen, Binchen Mao, Jingjing Wang, Meiling Zheng et al. "A living biobank of matched pairs of patient-derived xenografts and organoids for cancer pharmacology". PLOS ONE 18, n.º 1 (5 de enero de 2023): e0279821. http://dx.doi.org/10.1371/journal.pone.0279821.

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Patient-derived tumor xenograft (PDX)/organoid (PDO), driven by cancer stem cells (CSC), are considered the most predictive models for translational oncology. Large PDX collections reflective of patient populations have been created and used extensively to test various investigational therapies, including population-trials as surrogate subjects in vivo. PDOs are recognized as in vitro surrogates for patients amenable for high-throughput screening (HTS). We have built a biobank of carcinoma PDX-derived organoids (PDXOs) by converting an existing PDX library and confirmed high degree of similarities between PDXOs and parental PDXs in genomics, histopathology and pharmacology, suggesting “biological equivalence or interchangeability” between the two. Here we demonstrate the applications of PDXO biobank for HTS “matrix” screening for both lead compounds and indications, immune cell co-cultures for immune-therapies and engineering enables in vitro/in vivo imaging. This large biobank of >550 matched pairs of PDXs/PDXOs across different cancers could become powerful tools for the future cancer drug discovery.

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Ji, Yurou, Xinyu Li, Yue Qi, Jianguo Zhao, Wenwen Zhang y Pengpeng Qu. "Anlotinib Exerts Inhibitory Effects against Cisplatin-Resistant Ovarian Cancer In Vitro and In Vivo". Molecules 27, n.º 24 (14 de diciembre de 2022): 8873. http://dx.doi.org/10.3390/molecules27248873.

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Background: Anlotinib is a highly potent multi-target tyrosine kinase inhibitor. Accumulating evidence suggests that anlotinib exhibits effective anti-tumor activity against various cancer subtypes. However, the effects of anlotinib against cisplatin-resistant (CIS) ovarian cancer (OC) are yet to be elucidated. The objective of this study was to investigate the inhibitory effect of anlotinib on the pathogenesis of cisplatin-resistant OC. Materials and Methods: Human OC cell lines (A2780 and A2780 CIS) were cultured and treated with or without anlotinib. The effects of anlotinib on cell proliferation were determined using cell-counting kit-8 and colony-formation assays. To evaluate the invasion and metastasis of OC cells, we performed wound-healing and transwell assays. The cell cycle was analyzed via flow cytometry. A xenograft mouse model was used to conduct in vivo studies to verify the effects of anlotinib. The expression of Ki-67 in the tumor tissue was detected via immunohistochemistry. Quantitative real-time polymerase chain reaction and Western blotting were used to measure the mRNA and protein levels. Results: Our study revealed that anlotinib significantly inhibited the proliferation, migration, and invasion of A2780 and A2780 CIS in a dose-dependent way in vitro (p < 0.05). Through R software ‘limma’ package analysis of GSE15372, it was found that, in comparison with A2780, PLK2 was expressed in significantly low levels in the corresponding cisplatin-resistant strains. The ERK1/2/Plk2 signaling axis mediates the inhibitory effect of anlotinib on the proliferation and migration of ovarian cancer cell lines. Moreover, our research found that anlotinib effectively inhibited the growth of tumor cells in an OC xenograft mouse model. Conclusions: In this study, anlotinib showed excellent inhibitory effects against cisplatin-resistant OC both in vitro and in vivo. These results add to the growing body of evidence supporting anlotinib as a potential anticancer agent against OC.

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Chen, Bao-An, Jue-qiong Wang, Jian Cheng, Feng Gao, Wen-lin Xu, Hui-lin Shen, Jia-hua Ding et al. "Comparison of the Effects on Reversal of Multi-Drug Resistance of 5-Bromotetrandrine and Tetrandrine in K562/A02 Cell Line in Vivo and in Vitro". Blood 112, n.º 11 (16 de noviembre de 2008): 5059. http://dx.doi.org/10.1182/blood.v112.11.5059.5059.

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Abstract Objective This study was to compare the reversal effect of 5-bromotetrandrine (BrTet) with Tetrandrine (Tet) when combined with ADM on multidrug resistance cell line K562/A02 and to investigate the reversal mechanism of this new derivative. Methods The protein levels of P-glycoprotein (P-gp) were detected by fluorospectrophotometry and Western blot. The mRNA levels of P-gp were determined by RT-PCR. The in vivo effect of Tet was investigated using nude mice grafted with sensitive human leukemia cell line K562 and MDR cell line K562/A02. Results Flow cytometry assay showed that 1.0 μMol/L BrTet significantly increased the apoptosis percentage. BrTet also enhanced the intracellular accumulation of ADM in K562/A02 cells and its potency was greater than that of Tet at the same concentrations. BrTet inhibited the overexpression of P-gp and down regulated MDR1 mRNA expression in K562/A02 cells in a dose-dependent manner. In nude mice bearing K562 xenografts on the left flank and K562/A02 xenografts on the right flank, i.p. injection of 10 mg/kg BrTet significantly enhanced the antitumor activity of ADM against K562/A02 xenografts with inhibitory rates of 26.1%, while ADM alone inhibited the growth of KBv200 xenografts by only 5.8%. Conclusion BrTet showed significant MDR reversal activity in vitro and in vivo. Its activity may be related to the inhibition of P-gp overexpression and the increase in intracellular accumulation of anticancer drugs, which lead to more K562/A02 cells apoptosis.

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Hou, Chao, Dai-Han Zhou, Yong-Jian Wu, Xiao-Jun Dai, Qing-Ying Wang, Yin-Qiu Wu y En-Xin Zhang. "In Vitro and In Vivo Inhibitory Effect of Gujin Xiaoliu Tang in Non-Small Cell Lung Cancer". Evidence-Based Complementary and Alternative Medicine 2018 (9 de septiembre de 2018): 1–14. http://dx.doi.org/10.1155/2018/8936108.

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Non-small cell lung cancer (NSCLC) is a serious threat to people’s health. This study aims to determine the possible effect of Gujin Xiaoliu Tang (GJXLT) on NSCLC, which is an empirical formula from Professor Dai-Han Zhou. In this study, chromatographic fingerprinting of GJXLT and A549 cell model in vitro and in vivo was established. We cultured A549 cells in vitro and found that GJXLT inhibited A549 cell growth and induced apoptosis. Compared with the control group, the expression of p-STAT3 and VEGF proteins in the GJXLT groups was decreased. Similar findings were also observed in vivo. First, GJXLT inhibited the growth of transplanted tumor and did not reduce the weight of the tumor-bearing mice in comparison with that of the control group. Then, the Ki-67 expression of transplanted tumor in the GJXLT groups was decreased. In addition, the apoptosis rate of transplanted tumor in the GJXLT groups was increased. Overall, our data showed that GJXLT inhibited A549 cell proliferation and induced apoptosis in vivo and in vitro. Furthermore, GJXLT inhibited the growth of lung cancer xenograft in nude mice model with no obvious side effects. The anti-tumor effect of GJXLT might also be related to the inhibition of p-STATS and VEGF expression in the JAK2/STAT3 pathway. Our results demonstrated the potential of GJXLT as a novel treatment for NSCLC.

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AghaAmiri, Solmaz, Jo Simien, Alastair M. Thompson, Julie Voss, Sukhen C. Ghosh, Servando Hernandez Vargas, Sarah Kim, Ali Azhdarinia y Hop S. Tran Cao. "Comparison of HER2-Targeted Antibodies for Fluorescence-Guided Surgery in Breast Cancer". Molecular Imaging 2021 (1 de febrero de 2021): 1–12. http://dx.doi.org/10.1155/2021/5540569.

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Background. Although therapeutic advances have led to enhanced survival in patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer, detection of residual disease remains challenging. Here, we examine two approved anti-HER2 monoclonal antibodies (mAbs), trastuzumab and pertuzumab, as potential candidates for the development of immunoconjugates for fluorescence-guided surgery (FGS). Methods. mAbs were conjugated to the near-infrared fluorescent (NIRF) dye, IRDye800, and for quantitative in vitro assessment, to the radiometal chelator, desferrioxamine, to enable dual labeling with 89Zr. In vitro binding was evaluated in HER2-overexpressing (BT474, SKBR3) and HER2-negative (MCF7) cell lines. BT474 and MCF7 xenografts were used for in vivo and ex vivo fluorescence imaging. Results. In vitro findings demonstrated HER2-mediated binding for both fluorescent immunoconjugates and were in agreement with radioligand assays using dual-labeled immunoconjugates. In vivo and ex vivo studies showed preferential accumulation of the fluorescently-labeled mAbs in tumors and similar tumor-to-background ratios. In vivo HER2 specificity was confirmed by immunohistochemical staining of resected tumors and normal tissues. Conclusions. We showed for the first time that fluorescent trastuzumab and pertuzumab immunoconjugates have similar NIRF imaging performance and demonstrated the possibility of performing HER2-targeted FGS with agents that possess distinct epitope specificity.

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Alföldi, Balog, Faragó, Halmai, Kotogány, Neuperger, Nagy, Fehér, Szebeni y Puskás. "Single Cell Mass Cytometry of Non-Small Cell Lung Cancer Cells Reveals Complexity of In vivo And Three-Dimensional Models over the Petri-dish". Cells 8, n.º 9 (16 de septiembre de 2019): 1093. http://dx.doi.org/10.3390/cells8091093.

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Single cell genomics and proteomics with the combination of innovative three-dimensional (3D) cell culture techniques can open new avenues toward the understanding of intra-tumor heterogeneity. Here, we characterize lung cancer markers using single cell mass cytometry to compare different in vitro cell culturing methods: two-dimensional (2D), carrier-free, or bead-based 3D culturing with in vivo xenografts. Proliferation, viability, and cell cycle phase distribution has been investigated. Gene expression analysis enabled the selection of markers that were overexpressed: TMEM45A, SLC16A3, CD66, SLC2A1, CA9, CD24, or repressed: EGFR either in vivo or in long-term 3D cultures. Additionally, TRA-1-60, pan-keratins, CD326, Galectin-3, and CD274, markers with known clinical significance have been investigated at single cell resolution. The described twelve markers convincingly highlighted a unique pattern reflecting intra-tumor heterogeneity of 3D samples and in vivo A549 lung cancer cells. In 3D systems CA9, CD24, and EGFR showed higher expression than in vivo. Multidimensional single cell proteome profiling revealed that 3D cultures represent a transition from 2D to in vivo conditions by intermediate marker expression of TRA-1-60, TMEM45A, pan-keratin, CD326, MCT4, Gal-3, CD66, GLUT1, and CD274. Therefore, 3D cultures of NSCLC cells bearing more putative cancer targets should be used in drug screening as the preferred technique rather than the Petri-dish.

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Dankó, Titanilla, Gábor Petővári, Regina Raffay, Dániel Sztankovics, Dorottya Moldvai, Enikő Vetlényi, Ildikó Krencz et al. "Characterisation of 3D Bioprinted Human Breast Cancer Model for In Vitro Drug and Metabolic Targeting". International Journal of Molecular Sciences 23, n.º 13 (4 de julio de 2022): 7444. http://dx.doi.org/10.3390/ijms23137444.

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Monolayer cultures, the less standard three-dimensional (3D) culturing systems, and xenografts are the main tools used in current basic and drug development studies of cancer research. The aim of biofabrication is to design and construct a more representative in vivo 3D environment, replacing two-dimensional (2D) cell cultures. Here, we aim to provide a complex comparative analysis of 2D and 3D spheroid culturing, and 3D bioprinted and xenografted breast cancer models. We established a protocol to produce alginate-based hydrogel bioink for 3D bioprinting and the long-term culturing of tumour cells in vitro. Cell proliferation and tumourigenicity were assessed with various tests. Additionally, the results of rapamycin, doxycycline and doxorubicin monotreatments and combinations were also compared. The sensitivity and protein expression profile of 3D bioprinted tissue-mimetic scaffolds showed the highest similarity to the less drug-sensitive xenograft models. Several metabolic protein expressions were examined, and the in situ tissue heterogeneity representing the characteristics of human breast cancers was also verified in 3D bioprinted and cultured tissue-mimetic structures. Our results provide additional steps in the direction of representing in vivo 3D situations in in vitro studies. Future use of these models could help to reduce the number of animal experiments and increase the success rate of clinical phase trials.

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Ehrenberg, Karl Roland, Jianpeng Gao, Felix Oppel, Stephanie Frank, Na Kang, Sebastian M. Dieter, Friederike Herbst et al. "Systematic Generation of Patient-Derived Tumor Models in Pancreatic Cancer". Cells 8, n.º 2 (10 de febrero de 2019): 142. http://dx.doi.org/10.3390/cells8020142.

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In highly aggressive malignancies like pancreatic cancer (PC), patient-derived tumor models can serve as disease-relevant models to understand disease-related biology as well as to guide clinical decision-making. In this study, we describe a two-step protocol allowing systematic establishment of patient-derived primary cultures from PC patient tumors. Initial xenotransplantation of surgically resected patient tumors (n = 134) into immunodeficient mice allows for efficient in vivo expansion of vital tumor cells and successful tumor expansion in 38% of patient tumors (51/134). Expansion xenografts closely recapitulate the histoarchitecture of their matching patients’ primary tumors. Digestion of xenograft tumors and subsequent in vitro cultivation resulted in the successful generation of semi-adherent PC cultures of pure epithelial cell origin in 43.1% of the cases. The established primary cultures include diverse pathological types of PC: Pancreatic ductal adenocarcinoma (86.3%, 19/22), adenosquamous carcinoma (9.1%, 2/22) and ductal adenocarcinoma with oncocytic IPMN (4.5%, 1/22). We here provide a protocol to establish quality-controlled PC patient-derived primary cell cultures from heterogeneous PC patient tumors. In vitro preclinical models provide the basis for the identification and preclinical assessment of novel therapeutic opportunities targeting pancreatic cancer.

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Jian, Weiguo, Jonathan M. Levitt, Keith S. Chan, Seth P. Lerner y Guru Sonpavde. "The preclinical anti-angiogenic and pro-apoptotic activity of lenalidomide in urothelial carcinoma (UC)." Journal of Clinical Oncology 31, n.º 6_suppl (20 de febrero de 2013): 294. http://dx.doi.org/10.1200/jco.2013.31.6_suppl.294.

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294 Background: Lenalidomide (Len) is an immunomodulatory drug (IMiD) approved for hematologic conditions and demonstrates immune modulation, anti-angiogenic activity and direct anti-tumor cytotoxicity. A rationale can be made to evaluate the preclinical activity of Len in UC. Methods: The in vitro anti-tumor activity of Len was evaluated in 4 human (5637, TCC-SUP, RT4, RT112) and 1 murine (MB49) cell line. Anti-proliferative activity activity (MTT assay), apoptosis (Annexin-FITC immunohistochemistry [IHC], flow cytometry) and cell viability by colony forming assay were measured. In vivo activity of daily oral Len 10 mg/kg or placebo orally for 5 days a week for up to 4 weeks was examined in syngeneic immunocompetent C57BL/6 mice bearing subcutaneous (SC) MB49-Luc25 tumors and RT4 subcutaneous xenografts. Tumors underwent immunohistochemistry (IHC) for microvessel density (CD31), apoptosis (cleaved caspase [cc]-3) and CD3+/CD20+ lymphocyte infiltration. Cereblon, a molecular target of Len was analyzed by IHC. Results: In vitro cultures for 3 days with daily repletion of Len showed significant pro-apoptotic activity (flow cytometry) at low micromolar concentrations attainable in human subjects (2.2 µM) against RT4 cells, a superficially invasive human UC cell line. Long-term cultures of RT4 cells for 2 weeks with daily repletion of Len significantly reduced cell viability and colony forming ability. Cereblon expression was numerically lower in sensitive RT4 cells compared to resistant 5637 cells (p=NS). In the immunocompetent model in vivo, Len did not decrease tumor size, or increase cc-3 and CD3+/CD20+ lymphocytes, but post-Len tumors exhibited decreased CD31 (p<0.05). In RT4 xenografts, Len significantly decreased the size of tumors and CD31, and increased cc-3 (all p<0.05). Cereblon expression increased in Len treated RT4 xenografts (p=0.024). Conclusions: Lenalidomide demonstrated selective preclinical activity against superficially invasive low grade human UC cells attributable to direct tumor cell apoptosis and anti-angiogenic activity. Clinical evaluation in patients with low grade or non-invasive UC and further study of cereblon as a predictive biomarker may be warranted.

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Zhang, Yin, Lijuan Wang, Sirui Yu, Kongzhen Hu, Shun Huang, Youcai Li, Hubing Wu, Hongsheng Li y Quanshi Wang. "Synthesis and Preclinical Evaluation of the Fibrin-Binding Cyclic Peptide 18F-iCREKA: Comparison with Its Contrasted Linear Peptide". Contrast Media & Molecular Imaging 2019 (27 de junio de 2019): 1–11. http://dx.doi.org/10.1155/2019/6315954.

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Purpose. Cys-Arg-Glu-Lys-Ala (CREKA) is a pentapeptide which can target fibrin-fibronectin complexes. Our previous study has built a probe called iCREKA which was based on CREKA and has proved the feasibility and specificity of iCREKA by the fluorescence experiment. The purpose of this study is to achieve the 18F-labeled iCREKA and make preclinical evaluation of the 18F-iCREKA with comparison of its contrasted linear peptide (LP). Methods. CREKA, LP, and iCREKA were labeled by the Al18F labeling method, respectively. These 18F-labeled peptides were evaluated by the radiochemistry, binding affinity, in vitro stability, in vivo stability, micro-PET imaging, and biodistribution tests. Results. 18F-NOTA-iCREKA was stable both in vitro and in vivo. However, 18F-NOTA-CREKA and 18F-NOTA-LP were both unstable. The FITC or 18F-labeled iCREKA could be abundantly discovered only in matrix metalloproteinases- (MMPs-) 2/9 highly expressed U87MG cells, while the FITC or 18F-labeled LP could also be abundantly discovered in MMP-2/9 lowly expressed Caov3 cells. Biodistribution and micropositron emission tomography (PET) imaging revealed that the U87MG xenografts showed a higher uptake of 18F-NOTA-iCREKA than 18F-NOTA-LP while the Caov3 xenografts showed very low uptake of both 18F-NOTA-iCREKA and 18F-NOTA-LP. The tumor-to-muscle (T/M) ratio of 18F-NOTA-iCREKA (9.93 ± 0.42) was obviously higher than 18F-NOTA-LP (2.69 ± 0.35) in U87MG xenografts. Conclusions. The novel CREKA-based probe 18F-NOTA-iCREKA could get a high uptake in U87MG cells and high T/M ratio in U87MG mice. It was more stable and specific than the 18F-NOTA-LP.

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Dumitrescu, Cristina Rodica, Ionela Andreea Neacsu, Vasile Adrian Surdu, Adrian Ionut Nicoara, Florin Iordache, Roxana Trusca, Lucian Toma Ciocan, Anton Ficai y Ecaterina Andronescu. "Nano-Hydroxyapatite vs. Xenografts: Synthesis, Characterization, and In Vitro Behavior". Nanomaterials 11, n.º 9 (2 de septiembre de 2021): 2289. http://dx.doi.org/10.3390/nano11092289.

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This research focused on the synthesis of apatite, starting from a natural biogenic calcium source (egg-shells) and its chemical and morpho-structural characterization in comparison with two commercial xenografts used as a bone substitute in dentistry. The synthesis route for the hydroxyapatite powder was the microwave-assisted hydrothermal technique, starting from annealed egg-shells as the precursor for lime and di-base ammonium phosphate as the phosphate precursor. The powders were characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDAX), transmission electron microscopy (TEM), X-ray fluorescence spectroscopy (XRF), and cytotoxicity assay in contact with amniotic fluid stem cell (AFSC) cultures. Compositional and structural similarities or differences between the powder synthesized from egg-shells (HA1) and the two commercial xenograft powders—Bio-Oss®, totally deproteinized cortical bovine bone, and Gen-Os®, partially deproteinized porcine bone—were revealed. The HA1 specimen presented a single mineral phase as polycrystalline apatite with a high crystallinity (Xc 0.92), a crystallite size of 43.73 nm, preferential growth under the c axes (002) direction, where it mineralizes in bone, a nano-rod particle morphology, and average lengths up to 77.29 nm and diameters up to 21.74 nm. The surface of the HA1 nanoparticles and internal mesopores (mean size of 3.3 ± 1.6 nm), acquired from high-pressure hydrothermal maturation, along with the precursor’s nature, could be responsible for the improved biocompatibility, biomolecule adhesion, and osteoconductive abilities in bone substitute applications. The cytotoxicity assay showed a better AFSC cell viability for HA1 powder than the commercial xenografts did, similar oxidative stress to the control sample, and improved results compared with Gen-Os. The presented preliminary biocompatibility results are promising for bone tissue regeneration applications of HA1, and the study will continue with further tests on osteoblast differentiation and mineralization.

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Choudhary, Rashmi, Brian Freed, James DeGregori y Christopher C. Porter. "Knockdown of HPRT Enables Selection of Genetically Modified Human Hematopoietic Progenitor Cells." Blood 116, n.º 21 (19 de noviembre de 2010): 3772. http://dx.doi.org/10.1182/blood.v116.21.3772.3772.

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Abstract Abstract 3772 Genetic modification of autologous hematopoietic stem cells (HSC) has the potential for effective treatment of a wide variety of inherited blood disorders. However, HSC gene therapy has shown limited clinical efficacy (with notable exceptions), in part because of the small proportion of engrafted genetically corrected HSCs. The use of drug-resistance genes to enable selection for transduced HSCs has been explored, but with limited success. Previous studies from our laboratory have indicated that murine HSC can be selected with 6-Thioguanine (6TG), a relatively non-toxic drug used in the treatment of leukemias, after knocking down the expression of hypoxanthine-guanine phosphoribosyltransferase (HPRT), an enzyme that metabolizes 6TG to its active state. We sought to determine if these findings can be translated to human hematopoietic cells. In the present study, we transduced human myeloid (Molm13, MV4-11) and lymphoid cell lines (Reh) with lentiviral vectors expressing shRNA constructs targeting HPRT or a non-targeted control sequence (Ctrl). Two of the most promising constructs directed against HPRT (491 and 50) were studied in more detail to determine which is most effective. Cells were selected in puromycin and cell lysates analyzed for HPRT gene expression. Reverse-transcription, real-time PCR (RT qPCR) and western blotting demonstrated that construct 491 was most efficient in knocking down HPRT in human hematopoietic cell lines compared to construct 50 (and Ctrl). To determine whether knockdown of HPRT provided resistance to 6TG, cells were cultured in the absence or presence of different doses of 6TG and live cell concentrations were determined. While Ctrl transduced cells decreased in a dose dependent manner after 72h of 6TG treatment, cells transduced with constructs 491 and 50 were relatively resistant to 6TG. IC50 values for construct 491 were significantly higher (114μM for Molm13 and 46μM for Reh cell lines) than construct 50 (1μM for Molm13 and 10μM for Reh) in comparison to control transduced cells (0.4μM for Molm13 and 3.5μM for Reh). We assessed cell death in human hematopoietic cell lines by annexin V staining after exposure to 6TG at 48 and 72h. As expected, control transduced cells died of apoptosis upon 6TG treatment, while 491 and 50 transduced cells were resistant. Furthermore, 491 transduced cells were more resistant to apoptosis than 50 transduced cells. Based on these results, construct 491 was used to transduce human CD34+ progenitor cells isolated from umbilical cord blood along with control shRNA. Transduction efficiency varied from 25–35% as determined by %GFP expression by flow cytometry. Sorted GFP+ cells showed reduced expression of HPRT in 491 transduced cells compared to controls, as measured by RT qPCR. Similar to the effects in cell lines, in vitro proliferation of control transduced CD34+ cells diminished in response to increasing 6TG concentrations. There was an increase in the percentage of GFP+ cells in 6TG treated 491 transduced cells compared to untreated controls in a dose dependent fashion, indicating a selective advantage conferred to 491 transduced cells in the presence of 6TG. Importantly, 491 transduced cells continued to proliferate despite treatment with 6TG. Like 6TG, cisplatin requires mismatch repair (MMR) for cytotoxicity. To determine if HPRT knockdown had off-target effects impairing MMR, transduced cells were also treated with cisplatin. Both control and 491 transduced cells stopped proliferating in the presence of cisplatin indicating that MMR remained intact. These data indicate that human hematopoietic progenitor cells can be selected in vitro by knock-down of HPRT and treatment with 6TG. Xenografts of Ctrl and 491 transduced human CD34+ cord blood cells have been generated and are being treated with 6TG to determine if human cells can be selected with 6TG in vivo. Disclosures: Off Label Use: Off label use of 6-thioguanine will be suggested.

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36

Sharma, Sunil, Raffaella Soldi, Glynn Weldon Gilcrease y Stephen Horrigan. "Preclinical activity of BC2059, a novel compound that degrades beta-catenin, in colon cancer models." Journal of Clinical Oncology 30, n.º 15_suppl (20 de mayo de 2012): e14090-e14090. http://dx.doi.org/10.1200/jco.2012.30.15_suppl.e14090.

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e14090 Background: BC2059 (BetaCat Pharmaceuticals) is a novel small molecule that degrades ß-catenin in a proteosomally dependent manner in cancer cells. Methods: We tested the activity of BC2059 in vitro, in patient derived colon cancers in 3-dimensional cultures and in vivo using HT-29 xenografts. We also used a novel doxycycline driven siRNA model that downregulates ß-catenin to test activity of BC2059. Results: BC2059 was highly active with IC90s in MTS assays (μM): SW480 (0.44), Colo205 (0.66), Colo201 (0.03), HT29 (0.92) and relatively inactive in SW48 (9.83) or L cells (normal) (4). In a 3-Dimensional culture system where we grew patient-derived colon cancer cells in a matrigel system and measured cell death by ethidium bromide exclusion, surprisingly, the average EC50 was 200 picomolar indicating that the compound was much more effective in patient derived samples. In matrigel tumor invasion assays, BC2059 demonstrated potent inhibition of tumor invasion. In HT-29 mouse xenografts, BC2059 series demonstrated tumor growth inhibition with no weight loss with depletion of ß-catenin. We also used chromatin immunoprecipitation (CHIP) assays to demonstrate depletion of ß-catenin on myc and axin promoters. In combination experiments, BC2059 displayed synergy in vitro with 5-fluorouracil in vitro. We used a doxycycline driven siRNA system in colon cancer cell lines and show that the compound activity is synergistic with depletion of ß-catenin. We also conducted combination of BC2059 series of compounds using a proteasome inhibitor MG132 and demonstrate reversal of activity with proteasome inhibition. Conclusions: In conclusion, BC2059 demonstrates potent activity in vitro and in vivo against colon cancer models singly or in combination. Further, it is surprisingly potent in patient derived colon cancer models. It appears to degrade ß-catenin in a proteosomally dependent manner on important effectors like myc and axin. It merits further evaluation in this tumor type.

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37

Patel, Bella, Dey Aditi, Ehsan Ghorani, Yogesh Malam, Steele Andy, R. Wickremasinghe, Rai Lena y Adele Fielding. "Vaccine Measles Virus Has Therapeutic Potential In B Cell Malignancy." Blood 116, n.º 21 (19 de noviembre de 2010): 3757. http://dx.doi.org/10.1182/blood.v116.21.3757.3757.

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Abstract Abstract 3757 Replicating viruses that selectively lyse transformed cells are attractive agents for cancer therapy. The vaccine strain of measles virus has proven oncolytic activity in various murine models of malignancy including myeloma and lymphoma. These pre-clinical reports of MV efficacy have led to advanced phase clinical trial. In the study here we investigate the anti-tumour potential of MV in 2 novel disease targets:- adult B lineage acute lymphoblastic leukaemia (ALL) and Chronic lymphocytic leukaemia (CLL) using in-vitro and in-vivo models. MV derived from the Edmonston strain genetically engineered to express GFP was used to infect primary ALL (n = 6) and chronic lymphocytic leukaemia (CLL, n = 7) cells. All CLL and ALL cells expressed the MV receptor CD46 and were efficiently infected by MV-GFP as indicated by quantitation of viral nucleocapsid mRNA by RQ-PCR and immunoblotting of viral proteins N and H. Large multinucleated syncytia, characteristic of MV- induced cytopathology, were found in all infected ALL cultures, by contrast syncitium formation was much less prominent in the infected CLL specimens. Despite this, both CLL and ALL cells were efficiently killed by MV-GFP, as characterised by viability assays and immunoblotting for PARP cleavage. To further probe the contribution of cell to cell fusion in MV induced oncolysis we used a relatively non-fusogenic strain of MV:- MV-Moraten to infect CLL and ALL specimens. As expected ALL and CLL cells infected with MV-Moraten lacked the typical features of MV induced cytopathology. Despite this cell viability was markedly reduced in both ALL and CLL cultures infected with MV-Moraten compared to uninfected controls suggesting that intracellular fusion might be dispensable for MV-induced oncolysis in our two models. To test whether MV had therapeutic efficacy in-vivo we established subcutaneous xenografts of pre-B ALL in CB17/SCID mice using the Nalm-6 cell line and administered 1 × 107 pfu of MV (n==12) or UV inactivated MV (n=12) intratumorally on 10 occasions. In vivo MV administration had striking antitumour activity resulting in complete resolution of 11/12 or regression (1/12) of established subcutaneous pre-B ALL tumours by week 4. In contrast, all UV-MV treated tumours progressed. The differences in tumour growth between the MV treated and UV-MV control groups was significantly different (p < 0.0001, Figure 1). To test for MV-induced oncolysis in a model more closely related to ALL in humans we used a disseminated pre-B ALL model established by tail vein injection of 1 × 106 Nalm-6 cells. 1 × 106 pfu of MV or UV-MV was administered by the intravenous route six times. Eleven of twelve mice receiving replication competent MV remain disease free whereas 6/7 mice receiving tail vein administered UV MV had become moribund by 67 days (Figure 2). Bone marrow examination of moribund mice revealed 52 – 99% of CD19+/CD10+ Nalm-6 cells present. Overall, our data suggest that both ALL and CLL are targets for MV-mediated lysis in vitro. The significant antineoplastic activity of MV against both subcutaneous and disseminated ALL xenografts holds great promise towards developing vaccine MV as a therapeutic tool in adult ALL. Figure 1 Regression of Nalm-6 subcutaneous xenografts in SCID mice after intratumoral injection of MV. Figure 1. Regression of Nalm-6 subcutaneous xenografts in SCID mice after intratumoral injection of MV. Figure 2 Prolonged survival of disseminated Nalm-6 SCID xenografts after intravenous injection of MV. Figure 2. Prolonged survival of disseminated Nalm-6 SCID xenografts after intravenous injection of MV. Regression of Nalm-6 subcutaneous xenografts in SCID mice after intratumoral injection of MV. Prolonged survival of disseminated Nalm-6 SCID xenografts after intravenous injection of MV. Disclosures: No relevant conflicts of interest to declare.

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38

Swasdison, S. y R. Mayne. "Formation of highly organized skeletal muscle fibers in vitro. Comparison with muscle development in vivo". Journal of Cell Science 102, n.º 3 (1 de julio de 1992): 643–52. http://dx.doi.org/10.1242/jcs.102.3.643.

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Two methods were developed in which long-term cultures of quail skeletal muscle were established so that all of the muscle fibers develop in a highly oriented manner. The muscle fibers became spontaneously and vigorously contractile and established strong connections with the extracellular matrix at their ends that closely duplicate the structure of the myotendinous junction. A continuous basal lamina was formed around each muscle fiber that contained type IV collagen, laminin and heparan sulfate proteoglycan. With one of the methods, an extensive extracellular matrix developed around each muscle fiber that was highly organized with the formation of a distinctive epimysium, perimysium and endomysium. Analysis of the cultures by both methods for different isoforms of myosin showed expression of an adult form of myosin by some of the muscle cells. The results therefore demonstrate that muscle development in the present culture systems proceeds extensively for several weeks. It will now be possible to investigate directly the structure of the connections between muscle fibers and the extracellular matrix.

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39

Maier, Armin, Monika Engelhardt, Heinz-Herbert Fiebig y Julia Schüler. "Profiling of 24 Standard of Care Drugs in a Panel of 20 Human Hematological Cell Lines Using Xenograft-Derived Three-Dimensional (3D) Cultures Ex Vivo and In Vivo". Blood 118, n.º 21 (18 de noviembre de 2011): 4995. http://dx.doi.org/10.1182/blood.v118.21.4995.4995.

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Abstract Abstract 4995 Introduction: Leukemia and lymphoma account for a notable proportion of cancers worldwide. The heterogeneity and biological characteristics of hematological malignancies induce unique therapeutic challenges. It is well known that pluripotent as compared to differentiated cells possess the potential for anchorage independent growth in semisolid medium. This can be monitored via clonogenic or colony formation assays, in which cells grow in vitro in a three-dimensional (3D) manner without adherence to plastic culture material support. These assays can be utilized to evaluate growth and drug sensitivity of tumor stem and progenitor cells (Fiebig HH et al. Eur J Cancer 40:802, 2004). In addition, these 3D cell culture assays often mimic the in vivo scenario better than 2D cell culture assays with adherent tumor cells. Material and methods: For our ex vivo anti-tumor efficacy profiling using clonogenic assays, we established a panel of 20 hematological cell lines comprising different entities like acute lymphoblastic leukemia (ALL, 4 cell lines), acute myeloid leukemia (AML, 6 cell lines), chronic myeloid leukemia (CML, 5 cell lines), Hodgkin- (1 cell line) and non-Hodgkin-lymphoma (NHL, 3 cell lines), as well as multiple myeloma (MM, 3 cell lines). Tumor cells were injected into the flanks of NOD/SCID mice in order to obtain subcutaneous tumor xenografts, which were kept at low passages (n <3). These xenografts served as starting material either to prepare single cell suspensions for ex vivo analysis, or to carry out in vivo efficacy tests using either subcutaneous or disseminated growing tumor xenografts. Results: Twenty-four standard of care agents were tested in terms of their ex vivo chemosensitivity (e.g. cytarabine, cyclophosphamide, dexamethasone, doxorubicin, etoposide, melphalan, prednisolone, vincristine), including selected targeted drugs also (e.g. bortezomib, imatinib, nilotinib, sorafenib). The drugs showed diverse patterns of selectivity and potency: vincristine, doxorubicin and cytarabine, but also the proteasome inhibitor bortezomib exhibited pronounced activity with IC50 values in the nanomolar range (mean IC50 = 1 – 100nM), not only in their respective clinical application, but also in various other tumor entities, such as in ALL and AML with use of bortezomib. Differential activity was determined e.g. for prednisolone and dexamethasone, which were active in a micromolar range (mean IC50 = 22 – 58μM) in the ALL cell lines CCRF-CEM and MOLT-4, AML cell lines NOMO-1, NHL DAUDI and U-937, as well as the MM cell line IM-9. All-trans-retinoic acid (mean IC50 = 1.3μM) as well as interferon-gamma-1b (mean IC50 = 0.43 μM) showed specific activity patterns with pronounced growth inhibition in AML (3/6 tested AML cell lines: KG-1, NOMO-1, OCI-AML2), but also in CML (1/5 tested CML cell lines: EM-2) and MM (1/3 tested MM cell lines: L-363). The strong correlation of both tyrosine kinase inhibitors imatinib and nilotinib (spearman coefficient: 0.73, p <0.001) and their differential activity restricted to bcr-abl-positive cells served as a positive control for the implemented test system. In vivo follow-up testing in defined tumor xenografts confirmed the results obtained ex vivo. For example, cyclophosphamide that showed strong antitumor activity with use of the NHL cell line DAUDI via clonogenic assay (IC50 = 0.3μM), also induced tumor remissions of 80% in xenografts with subcutaneously growing DAUDI cells as compared to untreated control animals. Moreover, an exceedingly promising antitumor activity of sorafenib in AML cells assessed via clonogenic assay (mean IC50 0.84μM in AML cells vs. mean IC50 4.0μM over all tested entities) could be confirmed in the disseminated in vivo model using HL-60 cells (reduction of 99% vs. untreated control; Schueler J. et al. Blood 116 (21):2141, 2010). Conclusions: The presented panel screen using clonogenic assays is of great value for time and cost effective profiling of traditional cytotoxic as well as new targeted anti-cancer agents which can be confirmed in tumor models of hematological malignancies and can thereby guide to more effectively designed in vivo experiments. Diverse activity and resistance patterns ex vivo and in vivo also contribute to create clinical development strategies of standard and novel compounds. Disclosures: No relevant conflicts of interest to declare.

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40

Link, Kevin A., Shan Lin, Kakajan Komurov, Mark Wunderlich y James C. Mulloy. "Oncogene Dosage Is a Major Determinant of Leukemogenic Transformation by AE9a". Blood 118, n.º 21 (18 de noviembre de 2011): 1358. http://dx.doi.org/10.1182/blood.v118.21.1358.1358.

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Abstract Abstract 1358 Chromosomal translocation (8;21) results in the formation of the AML1-ETO (AE) leukemia-associated fusion protein. Roughly 70% of AE+ patient samples also harbor an alternatively spliced variant of AE, termed AE9a. AE9a promotes the leukemic transformation of mouse hematopoietic stem/progenitor cells without the need for secondary external cooperating oncogenes. By comparison, leukemia development in response to expression of full length AE requires one or more additional events. We extended these findings into a human cell system to determine whether AE9a is able to promote the transformation of human CD34+ cord blood (CB) cells to acute myeloid leukemia (AML). Transduction of CD34+ CB cells with AE9a promotes long-term culture potential, enhanced replating capacity, and expansion of CD34+ progenitor cells similar to full length AE. While we have not yet been able to generate AE9a leukemia in xenograft assays (despite several attempts), subcutaneous injection of AE9a cells promotes formation of a robust granulocytic sarcoma which is not seen using cells expressing full length AE. Several of our analyses have highlighted the importance of increased AE9a fusion protein expression in its enhanced function relative to full length AE, a concept that was also observed using the MLL-AF9 leukemia oncogene (Chen et. al, Cancer Cell, 2008). Indeed, flow cytometric sorting of freshly transduced AE or AE9a cultures based on high and low fusion protein expression revealed the importance of expression level for both AE and AE9a. High AE expression completely blocked colony formation and decreased cell expansion. These effects correlated with a dramatic upregulation of the cell cycle inhibitor p21. Conversely, high levels of AE9a did not upregulate p21 to the same degree, and colony formation and cell expansion were not as dramatically affected. In contrast, flow sort for cells expressing low levels of AE or AE9a had significantly less remarkable effects on cell function and p21 expression. Unexpectedly, AE9a-low cells eventually came to resemble the AE9a-high in terms of AE9a protein levels. These effects were not seen for full length AE sorted cultures. To determine whether similar effects were occurring in the murine AML model, we examined the effects of low and high expression levels of AE9a in mouse fetal liver cells. Corroborating our findings with the human cell model, AE9a-low samples promoted significantly less AML as compared to AE9a-high cells. This was not due to lack of engraftment of these cells or to loss of AE9a expression. Similar effects were found in vitro, where AE9a-low cells were unable to replate in methylcellulose assays while AE9a-high cells as well as AE-high and AE-low cells showed enhanced replating ability. Strikingly, the AML that did develop in mice transplanted with AE9a-low cells reverted to a very high level of AE9a protein expression, implying that increased expression of AE9a is essential for function. To better understand the mechanistic link between increased AE9a expression and AML development, we performed global gene expression analysis of murine progenitor cells expressing AE or AE9a (after three weeks of in vivo expansion). Analysis revealed a subset of genes that were highly repressed in AE9a expressing cells as compared to full length AE. Given that AE9a lacks the carboxy-terminal NHR3 and NHR4 domains of AE that interact with the NCoR and SMRT corepressors, the finding of significantly more repressed genes in AE9a cells is quite surprising. Network analysis has uncovered potential signaling pathways that may be involved in AE9a mediated transformation. Uncovering the mechanism of AE9a function could lead to a better understanding of t(8;21)-associated function in human AML. Disclosures: No relevant conflicts of interest to declare.

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Sidorcenco, Vasile, Luisa Krahnen, Marion Schulz, Janina Remy, Donat Kögel, Achim Temme, Ute Krügel, Heike Franke y Achim Aigner. "Glioblastoma Tissue Slice Tandem-Cultures for Quantitative Evaluation of Inhibitory Effects on Invasion and Growth". Cancers 12, n.º 9 (21 de septiembre de 2020): 2707. http://dx.doi.org/10.3390/cancers12092707.

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Glioblastomas (GBMs) are the most malignant brain tumors and are essentially incurable even after extensive surgery, radiotherapy, and chemotherapy, mainly because of extensive infiltration of tumor cells into the adjacent normal tissue. Thus, the evaluation of novel drugs in malignant glioma treatment requires sophisticated ex vivo models that approach the authentic interplay between tumor and host environment while avoiding extensive in vivo studies in animals. This paper describes the standardized setup of an organotypic brain tissue slice tandem-culture system, comprising of normal brain tissue from adult mice and tumor tissue from human glioblastoma xenografts, and explore its utility for assessing inhibitory effects of test drugs. The microscopic analysis of vertical sections of the slice tandem-cultures allows for the simultaneous assessment of (i) the invasive potential of single cells or cell aggregates and (ii) the space occupying growth of the bulk tumor mass, both contributing to malignant tumor progression. The comparison of tissue slice co-cultures with spheroids vs. tissue slice tandem-cultures using tumor xenograft slices demonstrates advantages of the xenograft tandem approach. The direct and facile application of test drugs is shown to exert inhibitory effects on bulk tumor growth and/or tumor cell invasion, and allows their precise quantitation. In conclusion, we describe a straightforward ex vivo system mimicking the in vivo situation of the tumor mass and the normal brain in GBM patients. It reduces animal studies and allows for the direct and reproducible application of test drugs and the precise quantitation of their effects on the bulk tumor mass and on the tumor’s invasive properties.

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42

Bredeck, Gerrit, Angela A. M. Kämpfer, Adriana Sofranko, Tina Wahle, Veronika Büttner, Catrin Albrecht y Roel P. F. Schins. "Ingested Engineered Nanomaterials Affect the Expression of Mucin Genes—An In Vitro-In Vivo Comparison". Nanomaterials 11, n.º 10 (6 de octubre de 2021): 2621. http://dx.doi.org/10.3390/nano11102621.

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The increasing use of engineered nanomaterials (ENM) in food has fueled the development of intestinal in vitro models for toxicity testing. However, ENM effects on intestinal mucus have barely been addressed, although its crucial role for intestinal health is evident. We investigated the effects of ENM on mucin expression and aimed to evaluate the suitability of four in vitro models of increasing complexity compared to a mouse model exposed through feed pellets. We assessed the gene expression of the mucins MUC1, MUC2, MUC5AC, MUC13 and MUC20 and the chemokine interleukin-8 in pre-confluent and confluent HT29-MTX-E12 cells, in stable and inflamed triple cultures of Caco-2, HT29-MTX-E12 and THP-1 cells, and in the ileum of mice following exposure to TiO2, Ag, CeO2 or SiO2. All ENM had shared and specific effects. CeO2 downregulated MUC1 in confluent E12 cells and in mice. Ag induced downregulation of Muc2 in mice. Overall, the in vivo data were consistent with the findings in the stable triple cultures and the confluent HT29-MTX-E12 cells but not in pre-confluent cells, indicating the higher relevance of advanced models for hazard assessment. The effects on MUC1 and MUC2 suggest that specific ENM may lead to an elevated susceptibility towards intestinal infections and inflammations.

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43

Luo, Man-Li, Jingjing Li, Liping Shen, Junjun Chu, Qiannan Guo, Guorun Liang, Wei Wu, Jianing Chen, Rufu Chen y Erwei Song. "The Role of APAL/ST8SIA6-AS1 lncRNA in PLK1 Activation and Mitotic Catastrophe of Tumor Cells". JNCI: Journal of the National Cancer Institute 112, n.º 4 (9 de julio de 2019): 356–68. http://dx.doi.org/10.1093/jnci/djz134.

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Abstract Background Tumor growth can be addicted to vital oncogenes, but whether long noncoding RNAs (lncRNAs) are essential to cancer survival is largely uncharacterized. Methods We retrieved Gene Expression Omnibus datasets to identify lncRNA overexpression in 257 cancers vs 196 normal tissues and analyzed the association of ST8SIA6-AS1 (termed Aurora A/Polo-like-kinase 1 [PLK1]–associated lncRNA, APAL) with the clinical outcomes of multiple types of cancer from public RNA sequencing and microarray datasets as well as from in-house cancer cohorts. Loss- and gain-of-function experiments were performed to explore the role of APAL in cancers in vitro and in vivo. RNA pulldown and RNA immunoprecipitation were used to investigate APAL-interacting proteins. All statistical tests were two-sided. Results APAL is overexpressed in multiple human cancers associated with poor clinical outcome of patients. APAL knockdown causes mitotic catastrophe and massive apoptosis in human breast, lung, and pancreatic cancer cells. Overexpressing APAL accelerates cancer cell cycle progression, promotes proliferation, and inhibits chemotherapy-induced apoptosis. Mechanism studies show that APAL links up PLK1 and Aurora A to enhance Aurora A-mediated PLK1 phosphorylation. Notably, targeting APAL inhibits the growth of breast and lung cancer xenografts in vivo (MCF-7 xenografts: mean tumor weight, control = 0.18 g [SD = 0.03] vs APAL locked nucleic acids = 0.07 g [SD = 0.02], P < .001, n = 8 mice per group; A549 xenografts: mean tumor weight control = 0.36 g [SD = 0.10] vs APAL locked nucleic acids = 0.10 g [SD = 0.04], P < .001, n = 9 mice per group) and the survival of patient-derived breast cancer organoids in three-dimensional cultures. Conclusions Our data highlight the essential role of lncRNA in cancer cell survival and the potential of APAL as an attractive therapeutic target for a broad-spectrum of cancers.

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Janjigian, Yelena Yuriy, Christopher M. Gromisch, Gregory Carbonetti, Laura H. Tang, David Paul Kelsen, Daniel G. Coit, Efsevia Vakiani, Elisa de Stanchina y Vivian E. Strong. "Establishment of esophagogastric xenografts: A model for characterizing disease heterogeneity." Journal of Clinical Oncology 30, n.º 30_suppl (20 de octubre de 2012): 95. http://dx.doi.org/10.1200/jco.2012.30.30_suppl.95.

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95 Background: Gastric cancer is a heterogeneous disease that may be subdivided into distinct subtypes—proximal/gastroesophageal (GE) junction, diffuse/signet ring type, and distal gastric cancer/intestinal type—based on histopathologic and anatomic criteria. Each subtype is associated with unique epidemiology and gene expression. Human epidermal growth factor receptor (HER2) is a validated treatment target in gastric cancer. For patients with metastatic disease, the available cytotoxic agents are applied indiscriminately to all disease subtypes, and with only modest success. The purpose of this study is to establish xenograft models from gastric cancer subtypes to improve our understanding of disease heterogeneity and develop therapies geared for each subtype of gastric cancer. Methods: Fresh specimens obtained from resected primary or metastatic tumors under aseptic conditions. 1 g tumor samples injected SQ into flanks of NSG mice. Xenografts established after 5 passages and maintained by serial transplantation into new mice. Cell cultures established after 5 in vitro passages; cell lines after 15 passages Results: To date, 66 tumor samples have been implanted from which 16 xenografts have been established. The table below summarizes the results. Single-agent afatinib (pan-ErbB inhibitor) demonstrated antitumor activity in an HER2-positive xenograft established from MSKCC patient’s tumor harvested from a skin metastasis. Conclusions: We have established xenograft models of gastric cancer. In vivo testing of afatinib showed a reduction of tumor growth of HER2-positive gastric cancer. These models provide a platform to study potential therapeutics for esophagogastric cancer to further validate difference in their biology and guide rational design of clinical trials. [Table: see text]

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Xiao, Jerry, Richard Schlegel y Seema Agarwal. "Abstract 5123: Establishing circulating tumor cell-derived xenografts following a period of in vitro culture". Cancer Research 82, n.º 12_Supplement (15 de junio de 2022): 5123. http://dx.doi.org/10.1158/1538-7445.am2022-5123.

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Abstract Cancer metastasis—the spread of cancer cells from a primary node to a distant site—is responsible for as much as 90% of all cancer-associated deaths due to treatment resistance and increased tumor burden. Once established, metastatic nodules oftentimes exhibit distinct molecular phenotypes from their original primary tumor, undermining gold-standard methods for determining treatments for patients, which typically rely on molecular characterization of the primary tumor. Unfortunately, a lack of robust, scalable, and appropriate models for studying differences in patient-derived primary and metastatic tumors has hindered progress in identifying metastasis-specific therapies. Previously, we reported the ability to establish in vitro cultures of circulating tumor cells (CTCs), a unique precursor population of cells that exhibits an ability to escape the primary tumor but not yet fully complete metastasis. We have since expanded the application of this GU-CTC platform to culture CTCs from the blood of patients diagnosed with a variety of metastatic cancers, resulting in the successful culture of 31 unique patient-derived CTC cell lines. Furthermore, following an initial short-term culture period, we also performed subcutaneous injection of mixed CTC cultures into immunocompromised mice, resulting in not only primary tumor formation, but also systemic metastatic nodule formation in as short as 3 months. These resulting CTC-derived xenografts (CDXs) have been demonstrated using metastatic pancreatic, colorectal, and lung adenocarcinoma-derived CTCs. Encouragingly, all CDX models also exhibited replicable metastatic patterns upon reimplantation, reinforcing the important role of CTCs as precursors to metastasis. Bulk RNA-sequencing of patient-matched whole blood, cultured CTCs, and CDX-derived primary tumor and metastatic tissues further identified enrichment of an epithelial-mesenchymal transition as well as several cancer-specific gene signatures consistent with an invasive phenotype. This extended GU-CTC platform therefore enables not only the robust and rapid expansion of CTCs through both in vitro and in vivo methods, but also offers an avenue for personalized drug screens in the effort to target cancer metastasis. Citation Format: Jerry Xiao, Richard Schlegel, Seema Agarwal. Establishing circulating tumor cell-derived xenografts following a period of in vitro culture [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5123.

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Tyndyk, Margarita, Irina Popovich, A. Malek, R. Samsonov, N. Germanov, S. Golyadin, S. Mochalov, Sergey Pulnev y Viktor Anisimov. "ANTITUMOR EFFECT OF COLLOIDAL SILVER BISILICATE IN EXPERIMENTAL IN VITRO AND IN VIVO STUDIES". Problems in oncology 65, n.º 5 (1 de mayo de 2019): 760–65. http://dx.doi.org/10.37469/0507-3758-2019-65-5-760-765.

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The paper presents the results of the research on the antitumor activity of a new drug - atomic clusters of silver (ACS), the colloidal solution of nanostructured silver bisilicate Ag6Si2O7 with particles size of 1-2 nm in deionized water. In vitro studies to evaluate the effect of various ACS concentrations in human tumor cells cultures (breast cancer, colon carcinoma and prostate cancer) were conducted. The highest antitumor activity of ACS was observed in dilutions from 2.7 mg/l to 5.1 mg/l, resulting in the death of tumor cells in all studied cell cultures. In vivo experiments on transplanted Ehrlich carcinoma model in mice consuming 0.75 mg/kg ACS with drinking water revealed significant inhibition of tumor growth since the 14th day of experiment (maximally by 52% on the 28th day, p < 0.05) in comparison with control. Subcutaneous injections of 2.5 mg/kg ACS inhibited Ehrlich's tumor growth on the 7th and 10th days of the experiment (p < 0.05) as compared to control.

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47

Suckert, Theresa, Treewut Rassamegevanon, Johannes Müller, Antje Dietrich, Antonia Graja, Michael Reiche, Steffen Löck, Mechthild Krause, Elke Beyreuther y Cläre von Neubeck. "Applying Tissue Slice Culture in Cancer Research—Insights from Preclinical Proton Radiotherapy". Cancers 12, n.º 6 (16 de junio de 2020): 1589. http://dx.doi.org/10.3390/cancers12061589.

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A challenge in cancer research is the definition of reproducible, reliable, and practical models, which reflect the effects of complex treatment modalities and the heterogeneous response of patients. Proton beam radiotherapy (PBRT), relative to conventional photon-based radiotherapy, offers the potential for iso-effective tumor control, while protecting the normal tissue surrounding the tumor. However, the effects of PBRT on the tumor microenvironment and the interplay with newly developed chemo- and immunotherapeutic approaches are still open for investigation. This work evaluated thin-cut tumor slice cultures (TSC) of head and neck cancer and organotypic brain slice cultures (OBSC) of adult mice brain, regarding their relevance for translational radiooncology research. TSC and OBSC were treated with PBRT and investigated for cell survival with a lactate dehydrogenase (LDH) assay, DNA repair via the DNA double strand break marker γH2AX, as well as histology with regards to morphology. Adult OBSC failed to be an appropriate model for radiobiological research questions. However, histological analysis of TSC showed DNA damage and tumor morphological results, comparable to known in vivo and in vitro data, making them a promising model to study novel treatment approaches in patient-derived xenografts or primary tumor material.

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48

Fautrel, Alain, Christophe Chesné, André Guillouzo, Georges De Sousa, Michel Placidi, Roger Rahmani, Françoise Braut et al. "A Multicentre Study of Acute In Vitro Cytotoxicity in Rat Hepatocytes: Tentative Correlation Between In Vitro Toxicities and In Vivo Data". Alternatives to Laboratory Animals 21, n.º 2 (abril de 1993): 281–84. http://dx.doi.org/10.1177/026119299302100223.

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A multicentre validation study of the acute in vitro cytotoxicities of 31 liquid or solid chemicals was carried out by six laboratories, using primary rat hepatocyte cultures as a model system. We report here a comparison of neutral red uptake IC50 and LD50 values. Oral, i.p. and i.v. LD50 values were available for 27, 24 and 18 chemicals, respectively, and an IC50 value was obtained for 15, 14 and 11 of these compounds, respectively. A significant correlation was found only between IC50 and i.v. LD50 values.

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49

Marques da Costa, Maria Eugénia, Antonin Marchais, Anne Gomez-Brouchet, Bastien Job, Noémie Assoun, Estelle Daudigeos-Dubus, Olivia Fromigué, Conceição Santos, Birgit Geoerger y Nathalie Gaspar. "In-Vitro and In-Vivo Establishment and Characterization of Bioluminescent Orthotopic Chemotherapy-Resistant Human Osteosarcoma Models in NSG Mice". Cancers 11, n.º 7 (17 de julio de 2019): 997. http://dx.doi.org/10.3390/cancers11070997.

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Osteosarcoma, the most common bone malignancy with a peak incidence at adolescence, had no survival improvement since decades. Persistent problems are chemo-resistance and metastatic spread. We developed in-vitro osteosarcoma models resistant to chemotherapy and in-vivo bioluminescent orthotopic cell-derived-xenografts (CDX). Continuous increasing drug concentration cultures in-vitro resulted in five methotrexate (MTX)-resistant and one doxorubicin (DOXO)-resistant cell lines. Resistance persisted after drug removal except for MG-63. Different resistance mechanisms were identified, affecting drug transport and action mechanisms specific to methotrexate (RFC/SCL19A1 decrease, DHFR up-regulation) for MTX-resistant lines, or a multi-drug phenomenon (PgP up-regulation) for HOS-R/DOXO. Differential analysis of copy number abnormalities (aCGH) and gene expression (RNAseq) revealed changes of several chromosomic regions translated at transcriptomic level depending on drug and cell line, as well as different pathways implicated in invasive and metastatic potential (e.g., Fas, Metalloproteinases) and immunity (enrichment in HLA cluster genes in 6p21.3) in HOS-R/DOXO. Resistant-CDX models (HOS-R/MTX, HOS-R/DOXO and Saos-2-B-R/MTX) injected intratibially into NSG mice behaved as their parental counterpart at primary tumor site; however, they exhibited a slower growth rate and lower metastatic spread, although they retained resistance and CGH main characteristics without drug pressure. These models represent valuable tools to explore resistance mechanisms and new therapies in osteosarcoma.

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50

Li, Hua, Yubin Wang y FuXiang Zhou. "Effect of ex vivo-expanded γδ-T cells combined with galectin-1 antibody on the growth of human cervical cancer xenografts in SCID mice". Clinical & Investigative Medicine 33, n.º 5 (1 de octubre de 2010): 280. http://dx.doi.org/10.25011/cim.v33i5.14353.

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Objective: To investigate the antitumor activity of ex vivo-expanded γδ-T cells derived from tumor-infiltrating lymphocytes(γδTILs) from cervical cancer patients when combined with galectin-1 antibody and studied both in vitro and in vivo. Methods: The presence of γδTILs in cervical cancer specimens was detected by immunohistochemistry and γδTILs were expanded using the solid-phase antibody method. The expression of galectin-1 by the human cervical cancer cell line, SiHa, was measured by Western blot and ELISA. In vitro cytotoxic activities of expanded γδTILs, with or without galectin-1 inhibitor, were determined using the LDH-release test. In vivo antitumor activity of γδTILs, combined with galectin-1 antibody, was evaluated using the SCID mouse model. Results: γδTILs existed in the cervical cancer and the percentage of TCRγδ+ cells in γδTILs after ex vivo expansion was 91.2±1.2% detected by flow cytometry. SiHa cell expressed and secreted galectin-1 as measured by Western blot and ELISA. Expanded γδTILs from human cervical cancer demonstrated marked cytotoxicity to SiHa or Hela cells. In comparison with non-treated group, the cytotoxicity of γδ TILs towards SiHa or Hela cell was significantly increased when effector and target cells were incubated with either lactose or galectin-1 antibody at E/T ratio of 1:1 (p < 0.05). γδTILs, in combination with galectin-1 antibody treatment, significantly suppressed the growth of xenografts in SCID mice, in comparison with all other groups (p < 0.05). γδTILs alone also showed the ability to inhibit tumour growth in vivo, but were more efficient when combined with specific antibody (p < 0.05). Conclusion: Taken together, our results suggest that γδ-T cells, combined with galectin-1 antibody treatment, could be a more effective adoptive immunotherapy for patients with cervical cancer than traditional adoptive immunotherapy methods.

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