Chemotherapy sensitivity testing on ovarian cancer cells isolated from malignant ascites

EM-transcriptomic signature predicts drug response in advanced stages of high-grade serous ovarian carcinoma based on ascites-derived primary cultures

Introduction: High-grade serous ovarian carcinoma (HGSOC) remains a medical challenge despite considerable improvements in the treatment. Unfortunately, over 75% of patients have already metastasized at the time of diagnosis. Advances in understanding the mechanisms underlying how ascites cause chemoresistance are urgently needed to derive novel therapeutic strategies. This study aimed to identify the molecular markers involved in drug sensitivity and highlight the use of ascites as a potential model to investigate HGSOC treatment options. Methods: After conducting an in silico analysis, eight epithelial-mesenchymal (EM)-associated genes related to chemoresistance were identified. To evaluate differences in EM-associated genes in HGSOC samples, we analyzed ascites-derived HGSOC primary cell culture (AS), tumor (T), and peritoneal nodule (NP) samples. Moreover, in vitro experiments were employed to measure tumor cell proliferation and cell migration in AS, following treatment with doxorubicin (DOX) and cisplatin (CIS) and expression of these markers. Results: Our results showed that AS exhibits a mesenchymal phenotype compared to tumor and peritoneal nodule samples. Moreover, DOX and CIS treatment leads to an invasive-intermediate epithelial-to-mesenchymal transition (EMT) state of the AS by different EM-associated marker expression. For instance, the treatment of AS showed that CDH1 and GATA6 decreased after CIS exposure and increased after DOX treatment. On the contrary, the expression of KRT18 has an opposite pattern. Conclusion: Taken together, our study reports a comprehensive investigation of the EM-associated genes after drug exposure of AS. Exploring ascites and their associated cellular and soluble components is promising for understanding the HGSOC progression and treatment response at a personalized level.

A Recipe for Successful Metastasis: Transition and Migratory Modes of Ovarian Cancer Cells

One of the characteristic features of ovarian cancer is its early dissemination. Metastasis and the invasiveness of ovarian cancer are strongly dependent on the phenotypical and molecular determinants of cancer cells. Invasive cancer cells, circulating tumor cells, and cancer stem cells, which are responsible for the metastatic process, may all undergo different modes of transition, giving rise to mesenchymal, amoeboid, and redifferentiated epithelial cells. Such variability is the result of the changing needs of cancer cells, which strive to survive and colonize new organs. This would not be possible if not for the variety of migration modes adopted by the transformed cells. The most common type of metastasis in ovarian cancer is dissemination through the transcoelomic route, but transitions in ovarian cancer cells contribute greatly to hematogenous and lymphatic dissemination. This review aims to outline the transition modes of ovarian cancer cells and discuss the migratory capabilities of those cells in light of the known ovarian cancer metastasis routes.

Efficacy of Bispecific Antibody Targeting EpCAM and CD3 for Immunotherapy in Ovarian Cancer Ascites: An Experimental Study

OBJECTIVE

This study aimed to explore the value of M701, targeting epithelial cell adhesion molecule (EpCAM) and CD3, in the immunotherapy of ovarian cancer ascites by the in vitro assay.

METHODS

The expression of EpCAM in ovarian cancer tissues was analyzed by databases. The EpCAM expression and immune cell infiltration in different foci of ovarian cancer were detected by 8-channel flow cytometry. The toxic effect of M701 on OVCAR3 was tested using the in vitro cytotoxicity assay. The 3D cell culture and drug intervention experiments were performed to evaluate the therapeutic effect of M701 in ovarian cancer specimens. Flow cytometry was used to examine the effect of M701 on the binding of immune cells to tumor cells and the activation capacity of T cells.

RESULTS

The results of the bioinformatic analysis showed that the expression of EpCAM in ovarian cancer tissue was significantly higher than that in normal ovarian tissue. The 8-channel flow cytometry of clinical samples showed that the EpCAM expression and lymphocyte infiltration were significantly heterogeneous among ovarian cancer patients and lesions at different sites. The in vitro experiment results showed that M701 had a significant killing effect on OVCAR3 cells. M701 also obviously killed primary tumor cells derived from some patients with ovarian cancer ascites. M701 could mediate the binding of CD3⁺ T cells to EpCAM⁺ tumor cells and induce T cell activation in a dose-dependent manner.

CONCLUSION

M701 showed significant inhibitory activity on tumor cells derived from ovarian cancer ascites, which had a promising application in immunotherapy for patients with ovarian cancer ascites.

Fluorescence In Situ Hybridization (FISH) for the Characterization and Monitoring of Primary Cultures from Human Tumors

Genetic and drug sensitivity assays on primary cultures are not only of basic but also of translational interest and could eventually aid oncologists in the selection of treatments. However, cancer cells need to be identified and differentiated from the non-tumor cells always present in primary cultures. Also, successive passages can change the proportions of these two subpopulations. In this study, we propose fluorescence in situ hybridization (FISH) analysis on cell smears to determine the presence of tumor cells in primary cultures obtained from patients carrying translocations or copy number gains. FISH proved to be an easy, fast, economic, and reliable method of characterizing cell populations, which could be used repeatedly at different passages to monitor variations and to confirm the maintenance of translocations and copy number gains throughout the culture process.

ZEB2 facilitates peritoneal metastasis by regulating the invasiveness and tumorigenesis of cancer stem-like cells in high-grade serous ovarian cancers

Peritoneal metastasis is a common issue in the progression of high-grade serous ovarian cancers (HGSOCs), yet the underlying mechanism remains unconfirmed. We demonstrated that ZEB2, the transcription factor of epithelial–mesenchymal transition (EMT), was upregulated in ascites cells from HGSOC patients and in CD133⁺ cancer stem-like cells (CSLCs) from epithelial ovarian cancer (EOC) cell lines. SiRNA-mediated knockdown of ZEB2 in EOC cells decreased the percentage of CSLCs and reduced the colony forming potential, cell invasion capacity and expression of pluripotent genes Oct4 and Nanog. Inhibition of ZEB2 also induced cellular apoptosis and impacted the tumorigenicity of ovarian CSLCs. The mesenchymal markers N-cadherin and vimentin were downregulated, while the epithelial marker E-cadherin was upregulated after ZEB2 knockdown. MiR-200a, a molecule that downregulates ZEB2, had the opposite effect of ZEB2 expression in EOC-CSLCs. A retrospective study of 98 HGSOC patients on the relationship of ascites volume, pelvic and abdominal metastasis, International Federation of Gynecology and Obstetrics (FIGO) stage and the malignant involvement of abdominal organs and lymph nodes was performed. Patients with high expression of ZEB2 in tumour tissues had a higher metastasis rate and a poorer prognosis than those with low expression. The parameters of ZEB2 expression and ascites volume were strongly linked with the prognostic outcome of HGSOC patients and had higher hazard ratios. These findings illustrated that ZEB2 facilitates the invasive metastasis of EOC-CSLCs and can predict peritoneal metastasis and a poor prognosis in HGSOC patients.

Targeting P2 receptors in purinergic signaling: a new strategy of active ingredients in traditional Chinese herbals for diseases treatment

Adenosine triphosphate (ATP) and its metabolites adenosine diphosphate, adenosine monophosphate, and adenosine in purinergic signaling pathway play important roles in many diseases. Activation of P2 receptors (P2R) channels and subsequent membrane depolarization can induce accumulation of extracellular ATP, and furtherly cause kinds of diseases, such as pain- and immune-related diseases, cardiac dysfunction, and tumorigenesis. Active ingredients of traditional Chinese herbals which exhibit superior pharmacological activities on diversified P2R channels have been considered as an alternative strategy of disease treatment. Experimental evidence of potential ingredients in Chinese herbs targeting P2R and their pharmacological activities were outlined in the study.