Estrogen promotes the proliferation and migration of endometrial cancer cells by upregulating the expression of lncRNA HOTAIR.

OBJECTIVE: Estrogen (E2) is the main contributor to the progression of endometrial cancer (EC). The long noncoding RNA HOX antisense intergenic RNA (HOTAIR) is emerging as a new regulator in several cancer types. This study aimed to investigate the role of HOTAIR in EC development and identify the underlying molecular mechanisms. METHODS: HOTAIR expression levels in human EC tissues and the corresponding adjacent tissues and human EC Ishikawa cells were determined by quantitative PCR. Ishikawa cells were treated with E2 or estrogen receptor (ER) inhibitor ICI182780, transfected with siHOTAIR oligo, or infected with lentivirus expressing shHOTAIR/shNC, alone or in combinations. The protein expression of polycomb repressive complex 2 (PRC2) was evaluated by western blotting, and cell migration was measured by transwell assays. A xenograft tumorigenic model was established by inoculating control or stable shHOTAIR-infected Ishikawa cells into nude mice and implanting 17ß-estradiol release pellets. RESULTS: HOTAIR expression was significantly elevated in human EC tissues. E2 exposure markedly increased HOTAIR levels in Ishikawa cells. Notably, E2 increased the protein expression of PRC2 and promoted EC cell migration, which were dependent on HOTAIR expression, as HOTAIR knockdown abolished these effects of E2. Similarly, E2 promoted the in vivo proliferation of grafted Ishikawa cells via upregulated HOTAIR expression in nude mice. CONCLUSIONS: Human EC tissues highly express HOTAIR, and E2-induced EC progression depends on HOTAIR expression. This work suggests that the E2-HOTAIR axis is a potential therapeutic target in EC therapy.

Clinicopathological Characteristics and Prognostic Prediction in Pseudomyxoma Peritonei Originating From Mucinous Ovarian Cancer.

OBJECTIVE: To describe the clinicopathological characteristics of mucinous ovarian cancer (MOC)-derived pseudomyxoma peritonei (PMP) and identify prognostic factors for survival. METHODS: Medical records from patients with MOC-derived PMP who attended the Aerospace Center Hospital, Beijing, China between January 2009, and December 2019 were retrospectively reviewed. Survival analysis was performed with the Kaplan-Meier method, the log-rank test, and a Cox proportional hazards model. RESULTS: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for PMP originating from MOC were performed on 22 patients, who had a median age of 52 years at the time of surgery. At the last follow-up in June 2020, 9 (41%) patients were still alive. Median OS was 12 months (range, 1 to 102 months), and the 2-, 3-, and 5-year survival rates were 23, 9, and 5%, respectively. CONCLUSION: Histopathologic subtype and PCI may be applied as predictors of prognosis in patients with MOC-derived PMP. Patients with high-grade disease could benefit from completeness of cytoreduction (CCR) 0/1.