Stem Cell Reviews and Reports

Molecular Insights into Endometrial Cancer in Mice

Pluripotent, very small embryonic-like stem cells (VSELs) and the 'progenitors' endometrial stem cells (EnSCs) along with associated molecular changes in endometrial cancer, that developed seven months after neonatal exposure to estradiol in one of the sixty mice, were studied in the present study. Endocrine disruption affected both endometrium and myometrium, there was accumulation of endometrial fluid and significant hyperplasia. Disrupted endometrial-myometrial junction resulted in mobilization of myometrial cells into endometrium and epithelial and stromal cells into myometrium suggestive of adenomyosis. Markers specific for VSELs/ EnSCs (OCT-4, NANOG, SSEA-1, SCA-1, c-KIT) showed increased expression in uterine sections and marked upregulation of corresponding transcripts (Oct-4A, Oct-4, Sox-2, Nanog, Sca-1, c-Kit) was noted in RNA extracted from both uterine tissue and stem cells enriched from endometrial fluid. Hormonal receptors (ER-α, ER-β, PR, FSHR) were upregulated in both tumor sections and in endometrial fluid. ER-β and FSHR (Fshr3) expression was prominent suggesting a major role in endometrial cancer. Cancer cells showed global hypomethylation (reduced expression of 5-methyl cytosine), reduced expression of tumor suppressor gene (PTEN) and increased expression of cancer stem cells marker (CD166) which suggested dysregulation and aberrant oncogenic events. Increased expression of PCNA, Ki67, SOX-9 suggested excessive proliferation and hyperplasia which are predominant signs of endometrial cancer. Results suggest that VSELs increase in numbers and possibly transform into cancer stem cells (co-express CD166 and OCT-4) in endometrial cancer. Expression of OCT-4, CD133, ALDHA1 and CD166 in side-population cells from human endometrial cancer samples suggests a possible role of VSELs in human endometrial cancer as well.

Current Developments of CAR-T and CAR-NK Cell Therapies for Ovarian Cancer

Ovarian cancer (OC) remains the deadliest gynecological malignancy, characterized by late diagnosis, tumor heterogeneity, and chemotherapy resistance, contributing to poor survival rates. This comprehensive review explores the potential of chimeric antigen receptor (CAR)-T and CAR-natural killer (NK) cell therapies as emerging immunotherapies for OC. We examine key tumor-associated antigens, including folate receptor alpha (FRα), mesothelin (MSLN), HER2, EpCAM, MUC16, Tn-glycopeptide, TAG-72, and LGR5, which are overexpressed in OC and have shown promise in preclinical studies and early clinical trials for inducing tumor regression without MHC restrictions. While CAR-T cells have demonstrated significant antitumor cytotoxicity in preclinical models, their application in solid tumors like OC faces challenges, including immunosuppressive tumor microenvironments, antigen escape, cytokine release syndrome, and neurotoxicity. CAR-NK cells offer potential advantages, such as reduced toxicity, off-the-shelf availability, and efficacy against heterogeneous tumors, making them a promising complementary approach. This review discusses current research on dosing regimens and combination strategies involving checkpoint inhibitors, chemotherapy, and radiotherapy, as well as responses across histological subtypes. Drawing from ongoing early-phase trials and innovative approaches like CRISPR editing and dual-targeting, we highlight the progress and challenges in developing CAR-based therapies, underscoring their potential while emphasizing the need for further research to establish clinical efficacy in OC.