miR-142 Suppresses Endometrial Cancer Proliferation In Vitro and In Vivo by Targeting Cyclin D1

Endometrial cancer (EC), a prevalent gynecologic tumor, is a great threat to women. We aimed to explore miR-142's effects on EC and the relevant mechanisms. Cell proliferation was evaluated with MTT, cell counting, and colony formation assay. MRNA abundances of miR-142 and cyclin D1 (CCND1) were examined with quantitative real-time PCR. CCND1 protein level in cells was analyzed with Western blot. miR-142's downstream target was identified with targetscan and luciferase reporter assay. Nude mice were injected subcutaneously with Ishikawa (ISK) cells transfected with or without miR-142 mimics. Ki-67 and CCND1 expressions in tumors of xenograft mice were analyzed with immunohistochemical assay. miR-142 was expressed at a lower level in human EC tumor samples than matched normal tissues, and its mRNA level in EC patients without metastasis was higher than that in patients with metastatic EC. Additionally, low-level miR-142 was closely linked with the poor prognosis of EC patients. miR-142 restricted ISK and H...