MiR-449a functions as a tumor suppressor in endometrial cancer by targeting CDC25A

Abstract

Accumulating evidence has demonstrated that microRNAs (miRNAs) play critical roles in cancer initiation and development by functioning either as oncogenes or as tumor suppressors. The role of microRNA-449a (miR-449a) in endometrial cancer remains unclear. We examined the levels of miR-449a and miR-449b in benign endometrium, type I and type II endometrial cancer tissues by quantitative real-time polymerase chain reaction. To further investigate the roles of miR-449a in regulating the behavior of endometrial cancer cells, we overexpressed miR-449a in the endometrial cancer cell line HEC-1B, which had low endogenous miR-449a expression. We analyzed the effects of miR-449a overexpression on CDC25 expression, proliferation, invasion and apoptosis of HEC-1B cells. We found that miR-449a and miR-449b levels were markedly reduced in type II endometrial cancer tissues but not in type I endometrial cancer tissues compared with normal endometrium. Overexpression of miR-449a significantly inhibited the proliferation, invasion and clonogenic survival of HEC-1B cells. MiR-449a overexpression also induced apoptosis in HEC-1B cells. In addition, real-time RT-PCR and western blot analysis showed that CDC25A expression was suppressed by miR-449a overexpression. Our results suggest that miR-449a may act as a tumor suppressor by targeting CDC25A in endometrial cancer.

MicroRNA-449a Inhibits Proliferation and Induces Apoptosis by Directly Repressing E2F3 in Gastric Cancer

“…Despite increasing evidence pointing to a role for miR-449a as a tumor suppressor, the role of miR-449a in human gastric cancer remains unclear [14,15,16]. In the present study, miR-449a expression was downregulated in gastric cancer tissues and cell lines.…”

Loss of miR-449a in ERG-associated prostate cancer promotes the invasive phenotype by inducing SIRT1

“…Extensive research has shown that miR-449a functions as a tumor suppressor in variety of cancers including endometrial cancer [33], gastric adenocarcinoma [34], retinoblastoma [35], neuroblastoma [36] and bladder cancer [37] by reducing cell proliferation, migration and invasion. Recent reports indicate that miR-449a also suppresses the epithelial-mesenchymal transition and metastasis of hepatocellular carcinoma [38].…”

miR-652 Promotes Tumor Proliferation and Metastasis by Targeting RORA in Endometrial Cancer

“…Although previous studies found that differentially expressed miRNAs may be associated with the carcinogenesis of endometrial cancer (10,11), the roles and potential mechanisms of miRNAs in endometrial cancer are still largely unknown. Only few miRNAs, such as miR-145 (12), miR-181c (13), miR-200a, miR-200b (14), miR-218 (15), and miR-449a (16), have been studied for their roles in endometrial carcinogenesis. miR-652 has been reported to be an oncomir in human breast cancer (17), osteosarcoma (18), and rectal cancer (19), and a tumor suppressor gene in malignant pleural mesothelioma (20).…”