miR-944 inhibits cell migration and invasion by targeting MACC1 in colorectal cancer

Dysfunction of microRNAs (miRNAs) is strongly proved to participate in the pathogenesis and tumorigenicity of colorectal cancer (CRC). miR-944 was reported to play either oncogenic or tumor suppressive roles in human cancers. A recent study reported that the levels of miR-944 in recurrent CRC patients were evidently lower than that in non-recurrent cases, suggesting that miR-944 may function as a tumor suppressive miRNA in CRC. Yet, the clinical value and biological function of miR-944 remain rarely known in CRC. In the present study, we present that miR-944 level in CRC tissues is notably reduced compared to matched non-cancerous specimens. Its decreased level is evidently correlated with malignant clinical parameters and poor prognosis of CRC patients. Accordingly, the levels of miR-944 were obviously downregulated in CRC cells. Ectopic expression of miR-944 in CRC cells prominently inhibits the migration and invasion of tumor cells, while miR-944 knockdown increased these effects of CRC cells. Mechanically, miR-944 negatively regulated the metastasis-associated in colon cancer-1 (MACC1) abundance in CRC cells. Herein, MACC1 was found to be a downstream molecule of miR-944 in CRC. An inversely correlation between miR-944 and MACC1 was confirmed in CRC specimens. Furthermore, restoration of MACC1 expression could abrogate the anti-metastatic effects of miR-944 on CRC cells with enhanced cell migration and invasion. MACC1/Met/AKT signaling may be implicated with the function of miR-944 in CRC cells. Altogether, miR-944 potentially act as a prognostic predictor and a drug-target for CRC patients.