Hormone receptor expression in uterine sarcomas: prognostic and therapeutic roles.

OBJECTIVES.: The utility of hormone therapy in the management of uterine sarcomas is poorly defined. We hypothesize that estrogen receptor (ER) expression is common in uterine sarcomas, and carries prognostic significance. Further, we hypothesize that ER-positive uterine sarcomas respond to hormone therapy. METHODS.: We retrospectively reviewed charts of patients with uterine sarcomas. Stepwise Cox proportional hazards regression model was used to evaluate variables related to the risk of death: age, histology, stage, use of pelvic radiotherapy, and ER expression. In addition, we examined clinical outcomes in patients treated with aromatase inhibitors, megestrol acetate, depot medroxyprogesterone acetate, and tamoxifen. RESULTS.: Fifty-four patients underwent immunohistochemical staining, and 34 (63%) were ER-positive. Kaplan-Meier survival analysis and log-rank test indicated that patients with ER-positive sarcomas demonstrated improved overall survival when compared with ER-negative patients (median OS 36 vs. 16 months, p=0.004). Upon multivariate analysis, ER positivity retained significance as an independent predictor of survival (HR=0.32, CI 0.12-0.89, p=0.03). Four patients received hormonal treatment in the adjuvant setting and remained in remission (range of follow up: 18-68 months). Eighteen patients received hormone therapy in the setting of recurrent or progressive disease: fourteen (78%) demonstrated stable disease or complete or partial response (range of follow up: 6-124 months). CONCLUSIONS.: ER expression is common and is associated with improved overall survival in uterine sarcomas. Conducting immunohistochemical staining to ascertain ER status may aid with prognostication in this disease. Hormone therapy should be considered in patients with primary and recurrent ER-positive uterine sarcomas.

Snail knockdown reverses stemness and inhibits tumour growth in ovarian cancer.

To develop effective therapies for advanced high grade serous ovarian cancer (HGSOC), understanding mechanisms of recurrence and metastasis is necessary. In this study, we define the epithelial/mesenchymal status of cell lines that accurately model HGSOC, and evaluate the therapeutic potential of targeting Snai1 (Snail), a master regulator of the epithelial/mesenchymal transition (EMT) in vitro and in vivo. The ratio of Snail to E-cadherin (S/E index) at RNA and protein levels was correlated with mesenchymal morphology in four cell lines. The cell lines with high S/E index (OVCAR8 and COV318) showed more CSC-like, motile, and chemoresistant phenotypes than those with low S/E index (OVSAHO and Kuramochi). We tested the role of Snail in regulation of malignant phenotypes including stemness, cell motility, and chemotherapy resistance: shRNA-mediated knockdown of Snail reversed these malignant phenotypes. Interestingly, the expression of let-7 tumour suppressor miRNA was upregulated in Snail knockdown cells. Furthermore, knockdown of Snail decreased tumour burden in an orthotopic xenograft mouse model. We conclude that Snail is important in controlling HGSOC malignant phenotypes and suggest that the Snail/Let-7 axis may be an attractive target for HGSOC treatment.