Littérature scientifique sur le sujet « Curbing malignancy »

Diffuse peritoneal leiomyomatosis is a rare benign condition which has a multifactorial origin with genetic or hormonal component leading to metaplasia of peritoneal mesenchymal cells. Thus, a combination of radiology with clinical correlation is an ideal approach for diagnosis. Though benign, radiologically it could give a picture of malignancy. In our case, patient came with an acute presentation resembling torsion ovary which usually needs emergency detorsion. In this scenario, multiple radiology component directed the case towards malignancy while ultimately a history, clinical correlation and biopsy revealed its benign nature. Reviewing the reported cases of disseminated peritoneal leiomyomatosis (DPL) incidence has slightly increased in recent years and is more common in patients with a past history of unconfined laparoscopic myomectomy wherein spillage of the myoma content into the abdominal cavity can trigger DPL as these are hormone sensitive tissues. The indolent course of the disease usually suggests a borderline disease, but only histological and immunohistochemical studies can confirm DPL, showing smooth muscle cells without nuclear atypia, strongly expressing estrogen and progesterone receptors. Mainstay of treatment targets in curbing the hormone influence on DPL and surgical management.

The non-antimicrobial properties of tetracyclines such as anti-inflammatory, proanabolic and anti-catabolic actions make them effective pharmaceuticals for the adjunctive management of chronic inflammatory diseases. An over-exuberant inflammatory response to an antigenic trigger in periodontitis and other chronic inflammatory diseases could contribute to an autoimmune element in disease progression. Their adjunctive use in managing periodontitis could have beneficial effects in curbing excessive inflammatory loading from commonly associated comorbidities such as CHD, DM and arthritis. Actions of tetracyclines and their derivatives include interactions with MMPs, tissue inhibitors of MMPs, growth factors and cytokines. They affect the sequence of inflammation with implications on immunomodulation, cell proliferation and angiogenesis; these actions enhance their scope, in treating a range of disease entities. Non-antimicrobial chemically modified tetracyclines (CMTs) sustain their diverse actions in organ systems which include anti-inflammatory, anti-apoptotic, anti-proteolytic actions, inhibition of angiogenesis and tumor metastasis. A spectrum of biological actions in dermatitis, periodontitis, atherosclerosis, diabetes, arthritis, inflammatory bowel disease, malignancy and prevention of bone resorption is particularly relevant to minocycline. Experimental models of ischemia indicate their specific beneficial effects. Parallel molecules with similar functions, improved Zn binding and solubility have been developed for reducing excessive MMP activity. Curbing excessive MMP activity is particularly relevant to periodontitis, and comorbidities addressed here, where specificity is paramount. Unique actions of tetracyclines in a milieu of excessive inflammatory stimuli make them effective therapeutic adjuncts in the management of chronic inflammatory disorders. These beneficial actions of tetracyclines are relevant to the adjunctive management of periodontitis subjects presenting with commonly prevalent comorbidities addressed here.

Cancer cell aggressiveness, marked by actin cytoskeleton reconfiguration critical for metastasis, may result from an imbalanced ratio favoring γ-actin. Dysfunctional p53 emerges as a key regulator of invasiveness and migration in various cancer cells, both in vitro and in vivo. P53 inactivation (via mutants R175H, R248W, R273H, or TP53 repression) significantly enhanced the migration, invasion, and proliferation of human lung adenocarcinoma A549 cells in vitro and in vivo, facilitating intrapulmonary xenograft metastasis in athymic mice. Conversely, wild-type TP53 (TP53 WT) overexpression in p53-deficient non-small- cell lung cancer (NSCLC) H1299 cells substantially reduced proliferation and migration in vitro, effectively curbing orthotopic tumorigenicity and impeding in vivo metastasis. These alterations in cell motility were closely associated with actin cytoskeleton restructuring, favoring γ-actin, and coincided with ERK1/2-mediated signaling activation, unveiling an innovative regulatory mechanism in malignancy progression. Cancer cell aggressiveness, driven by actin cytoskeleton reorganization and a shift towards γ-actin predominance, may be regulated by p53 dysfunction, thereby providing novel insight into tumor progression mechanisms.

Abstract Pancreatic Ductal Adenocarcinoma (PDAC) is a deadly malignancy with poor prognosis and treatment options. Cancer associated fibroblasts (CAFs) play a complex role in the PDAC tumor microenvironment (TME), contributing significantly to the progression of the tumor and the dense desmoplastic stroma. Phosphatase and tensin homolog (PTEN) is a tumor suppressor and its loss in both the tumor and in CAFs is associated with increased tumor aggressiveness and resistance to therapy. Our group previously demonstrated PTEN loss occurs in CAFs in ~25% of PDAC patient samples, which correlated with worsened outcomes. In addition, PTEN expression was lost in 80% of SMA+ CAFs in mouse PDAC models. Genetic or pharmacologic inhibition of the hedegehog pathway leads to ubiquitin-dependent destruction of PTEN by the proteosome. However, little is known of the signals produced by tumor cells that trigger PTEN degradation in CAFs. In order to address this problem, we developed an in vitro assay system based on wild type murine PDAC-CAFs that expresses a PTEN-GFP fusion protein. Initially, we focused on IL6 and IL6 family members Leukemia Inhibitory Factor (LIF) and Oncostatin-M (OSM) and Transforming Growth Factor beta 1 (TGFb1). The SMO inhibitor GDC-0449 was used as a positive control. PTEN stability was evaluated using the LSM 880 confocal microscope and GFP+ cells were quantified with QuPath-0.4.3 and analyzed with GraphPad Prism. Among the repertoire of secreted factors, we found that only OSM and TGFb1 could destabilize PTEN after 48H of treatment. When queried against the single cell RNA sequence dataset produced by our lab, we observed that CD45+ leukocytes were the likely source of OSM whereas TGFb1 was produced by tumor cells, fibroblasts, and immune cells. In conclusion, OSM and TGFb1 can downregulate PTEN in CAFs in vitro. Current efforts are aimed at testing whether inhibition of these pathways can restore PTEN expression in mouse PDAC models, and in identifying signaling pathways and E3-ligases that mediate PTEN destruction. These pathways and interactions could be further exploited for selective inhibition aimed at therapeutic benefits in curbing PDAC progression. Citation Format: Ivo N. Woogeng, Lu Han, Samaneh Saberi, Cameron Bumbleburg, Joseph Beaudet, Sudarshana Sharma, Michael Ostrowski. Oncostatin-M and transforming growth factor-beta promote loss of PTEN in PDAC cancer associated fibroblasts [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr C041.

Medical and long-term care costs are increasing all over the world. In this study, we investigated the characteristics of groups with high cost of medical and long-term care to define targets for curbing social security costs. As a result, for the population covered by the National Health Insurance, a large portion of medical costs were incurred for mental disorders, malignant neoplasms, and lifestyle-related diseases. For those covered by the Late Elderly Health Insurance System, most medical costs were incurred for lifestyle-related diseases, femoral fractures, neurological diseases, mental disorders, pneumonia, malignant neoplasms, and Alzheimer’s disease. From multiple regression analysis, the hospitalization days, use of advanced medical treatment, outpatient days, and high long-term care level influenced the increased costs. On the other hand, disease characteristics had only a very low effect. These findings suggest that the target population has complex medical and long-term care needs because they have multiple diseases.

The Epstein-Barr virus (EBV) infects more than 95% of adults worldwide and is associated with various malignant tumors and immune diseases, imparting a huge disease burden on the human population. Available EBV vaccines are imminent. Prophylactic vaccines can effectively prevent the spread of infection, whereas therapeutic vaccines mainly stimulate cell-mediated immunity and kill infected cells, thus curbing the development of malignant tumors. Nevertheless, there are still no approved EBV vaccines after decades of effort. The complexity of the EBV life cycle, the lack of appropriate animal models, and the limited reports on adjuvant selection and immune responses are gravely impeding progress in EBV vaccines. The soluble gp350 vaccine could reduce the incidence of infectious mononucleosis (IM), which seemed to offer hope, but could not prevent EBV infection. Continuous research and vaccine trials provide deep insights into the structural biology of viruses, the designs for immunogenicity, and the evolving vaccine platforms. Moreover, the new vaccine candidates are expected to achieve further success via combined immunization to elicit both a dual protection of B cells and epithelial cells, and sustainable immunization against infected cells at several phases of infection.

Abstract Abstract 1981 Introduction: Immune reconstitution after HCT is important for curbing infections and malignancy. ATG has been increasingly used to prevent graft-vs-host disease (GVHD), however, its impact on immune reconstitution has not been well studied. Here we studied (1) immune reconstitution after ATG-conditioned HCT, (2) compared it to non-ATG-conditioned HCT, and (3) determined factors influencing the immune reconstitution. Patients and Methods: Immune subset cell counts were determined on day 28, 56, 84, 180, 365 and 730 post transplant in 125 recipients of allogeneic filgrastim-mobilized blood stem cells who received ATG (Thymoglobulin, 4.5 mg/kg) during conditioning. The subset counts were also determined in 47 non-ATG-conditioned patients (otherwise similarly treated). Subset counts (in blood) and ATG levels (in serum) were quantified by flow cytometry. Mann-Whitney rank sum test was used to compare subset counts (1) in ATG-conditioned patients vs donors, (2) in ATG-conditioned patients vs non-ATG-conditioned patients, and (3) between subgroups of ATG-conditioned patients; Spearman rank correlation test was used to determine associations between subset counts and ordinal variables like ATG levels. Results: (1) After ATG-conditioned HCT, the counts of the following subsets normalized (became not significantly lower than in donors) by day 28: NK cells, monocytes, myeloid dendritic cells (MDCs), and plasmacytoid dendritic cells (PDCs). The counts of the following subsets normalized by day 84: memory/effector CD8 T cells, and CD4−CD8− T cells. The counts of naïve B cells normalized by day 180. The counts of the following subsets have not normalized by day 365 or 730: memory B cells (both isotype switched and unswitched), both naïve and memory/effector CD4 T cells, naïve CD8 T cells, CD4+CD8+ T cells, and invariant NKT (iNKT) cells. (2) Compared to non-ATG-conditioned HCT, counts of B cells, CD4 T cells and CD8 T cells were significantly lower after ATG-conditioned HCT on day 28. Thereafter, recovery of both naïve and memory B cells and memory/effector CD8 T cells was significantly faster in ATG-conditioned patients, leading to higher total B and higher total CD8 T cell counts on day 84 (Figure). On the contrary, recovery of naïve CD8 T cells and both naïve and memory/effector CD4 T cells was significantly slower, the latter leading to low total CD4 T cell counts throughout the first year (Figure). (3) Reconstitution after ATG-conditioned HCT was influenced by (a) the number of cells of the same subset transferred with the graft in case of increased memory B cells, naïve CD4 T cells, naïve CD8 T cells, iNKT cells and MDCs, (b) age of recipient in case of decreased naïve CD4 T cells and naïve CD8 T cells, (c) cytomegalovirus (CMV) serostatus of recipient in case of increased memory/effector T cells, (d) GVHD in case of increased naïve B cells, and (e) day 7 or 28 ATG levels in case of decreased T cell subsets. Conclusion: (1) Reconstitution after ATG conditioned HCT is very fast for NK cells, monocytes, MDCs and PDCs, fast for memory/effector CD8 T cells and CD4−CD8− T cells, slow for naïve B cells, and very slow for memory B cells, both naïve and memory/effector CD4 T cells, naïve CD8 T cells, CD4+CD8+ T cells and iNKT cells. (2) Compared to no ATG, the patients conditioned with ATG have lower counts of B and T cells on day 28. Thereafter, the ATG-conditioned patients have faster recovery of both naïve and memory B cells and memory/effector CD8 T cells, and slower recovery of both naïve and memory/effector CD4 T cells and naïve CD8 T cells. (3) Similar to what has been described for non-ATG-conditioned HCT, reconstitution after ATG-conditioned HCT is influenced by the number of the immune cells transferred with the graft, recipient age, recipient CMV serostatus and GVHD. Moreover, the reconstitution after ATG-conditioned HCT is influenced by ATG clearance. Disclosures: No relevant conflicts of interest to declare.

The major type I interferon-producing plasmacytoid dendritic cells (pDC) surround and infiltrate certain tumors like malignant melanoma, head and neck cancer, and ovarian and breast cancer. The presence of pDC in these tumors is associated with an unfavorable prognosis for the patients as long as these cells are unstimulated. Upon activation by synthetic Toll-like receptor agonists or viruses, however, pDC develop cytotoxic activities. Viruses have the additional advantage to augment cytotoxic activities of pDC via lytic replication in malignant lesions. These effects turn cold tumors into hotspots, recruiting further immune cells to the site of inflammation. Activated pDC contribute to cross-presentation of tumor-associated antigens by classical dendritic cells, which induce cytotoxic T-cells in particular in the presence of checkpoint inhibitors. The modification of oncolytic herpes viruses via genetic engineering favorably affects this process through the enhanced production of pro-inflammatory cytokines, curbing of tumor blood supply, and removal of extracellular barriers for efficient viral spread. Importantly, viral vectors may contribute to stimulation of memory-type adaptive immune responses through presentation of tumor-related neo- and/or self-antigens. Eventually, both replication-competent and replication-deficient herpes simplex virus 1 (HSV-1) may serve as vaccine vectors, which contribute to tumor regression by the stimulation of pDC and other dendritic cells in adjuvant and neo-adjuvant situations.

Objective: In triple-negative breast cancer (CMTN), the standard therapeutic procedure is usually not very effective due to the aggressiveness of the disease. Therefore, it is important to identify and characterize new forms of treatment for this neoplasm. In this context, the study of the genetic material of diseases has gained notoriety among alternative forms of therapy, as long non-coding RNAs (IncRNAs) have been identified in neoplastic cells. Therefore, the aim of this study was to evaluate the use of epigenetics in the treatment of CMTN, with emphasis on lncRNAs. Methodology: A systematic review of the specialized scientific literature was carried out, in the PubMed database, with the descriptors: “breast cancer,” “epigenetic,” and “treatment”; the Boolean operator: “AND”; and the filters: “free full text,” “adults: 19+ years,” and publication date from 2021 to 2023. A total of 32 articles were identified, with 3 included Results: Epigenetics influences the treatment of breast cancer; as the lncRNA was found in neoplastic cells, it was possible to monitor the prognosis of the disease. The lncRNA Uc003xsl.1 was associated with a poor prognosis, as it was related to advanced stages of CMTN, increasing the transcriptional activity of NFkB, which promotes tumor progression. On the contrary, the lncRNA LINC00472 proved to be a marker of good prognosis, as it inhibited the proliferation, invasion, and migration of neoplastic cells in the CMTN. Furthermore, with regard to breast cancer, lncRNA IGF-2AS proved to be an important biomarker, as it slows tumor growth in vivo, repressing malignancy and tumor progression. Therefore, IncRNAs have gained notoriety in treatment as regulators of breast cancer tumorigenesis. Conclusion: Thus, the use of epigenetics in the treatment of CMTN has proven to be essential to curbing neoplastic cells, as it interferes with tumor proliferation in different ways, either by influencing transcription or by slowing down growth.