Hypoxia-Inducible MiR-210 Is an Independent Prognostic Factor and Contributes to Metastasis in Colorectal Cancer

MicroRNA-210 (miR-210), the master hypoxamir, plays pleiotropic roles in certain cancers; however, its role in the development of human colorectal cancer remains unclear. Herein, we report that miR-210 is frequently up-regulated in colorectal cancer tissues, with high miR-210 expression significantly correlating with large tumor size, lymph node metastasis, advanced clinical stage and poor prognosis. Functionally, miR-210 overexpression promotes the migration and invasion of colorectal cancer cells. Furthermore, miR-210 can be induced by hypoxia and mediates the hypoxia-induced metastasis of colorectal cancer cells. In addition, vacuole membrane protein 1 (VMP1) is identified as the direct and functional target of miR-210. Thus, miR-210 is a useful biomarker for hypoxic tumor cells and a prognostic factor that plays an essential role in colorectal cancer metastasis.