[Mechanism of miR-200b-3p-induced FOSL2 inhibitorion of endometrial cancer cell proliferation and metastasis].

Objective The purpose of this study was to investigate how miR-200b-3p inhibitors the proliferation and metastasis of endometrial cancer(EC) cells by inducing the expression of FOS-like antigen 2(FOSL2) of activator protein 1(AP1) transcription family. Methods Endometrial cancer cell line HEC-1-A was divided into 12 groups: NC-mimic (transfected with negative control NC mimic), miR-200b-3p mimic (transfected with miR-200b-3p mimic), NC-inhibitor (transfected with negative control NC inhibitor), miR-200b-3p inhibitor group (transfected with miR-200b-3p inhibitor), si-NC (transfected with negative control Si-NC), si-FOSL2 (transfected with si-FOSL2), oe-NC (transfected with negative control oe-NC), oe-FOSL2 group (oe-FOSL2), miR-200b-3p mimic+oe-NC group (co-transfected with miR-200b-3p mimic and oe-NC), miR-200b-3p mimic+oe-FOSL2 group (co-transfected with miR-200b-3p mimic and oe-FOSL2), miR-200b-3p inhibitor+si-NC group (co-transfected with miR-200b-3p inhibitor and si-NC), miR-200b-3p inhibitor+si-FOSL2 group (co-transfected with miR-200b-3p inhibitor and si-FOSL2). Real-time fluorescence quantitative PCR, Western blot, CCK-8 assay, scratch test and Transwell assay were used to detect the expression of miR-200b-3p mRNA, FOSL2 mRNA and protein expression level, cell proliferation, migration and invasion. Results In endometrial cancer cell lines, the expression of miR-200b-3p was significantly down-regulated, while the expression of FOSL2 was significantly up-regulated. Compared with NC-mimic group, the expression of FOSL2, N-cadherin and Vimentin in miR-200b-3p mimic group was significantly decreased, and the expression of E-cadherin was significantly increased. The cell proliferation, migration rate and the number of transmembrane cells were significantly decreased. Compared with the miR-200b-3p mimic+oe-NC group, the expression of FOSL2, N-cadherin and Vimentin in miR-200b-3p mimic+oe-FOSL2 group was significantly increased, and the expression level of E-cadherin was significantly decreased, and the cell proliferation, migration rate and the number of transmembrane cells were significantly increased. Compared with NC-inhibitor group, the expression of FOSL2, N-cadherin and Vimentin in miR-200b-3p inhibitor group was significantly increased, and the expression of E-cadherin was significantly decreased. The cell proliferation, migration rate and the number of transmembrane cells were significantly increased. Compared with the miR-200b-3p inhibitor+si-NC group, the expression of FOSL2, N-cadherin and Vimentin in miR-200b-3p inhibitor+si-FOSL2 group was significantly decreased, and the expression of E-cadherin was significantly increased; the cell proliferation, migration rate and the number of transmembrane cells were significantly decreased. Conclusion The expression of miR-200b-3p in endometrial cancer cells is down-regulated, which can inhibitor the proliferation, migration and invasion of endometrial cancer cells by regulating the EMT process, and its mechanism is related to its targeted negative regulation of FOSL2 expression.