miR-3133 is an unfavorable prognosis factor and tumor suppressor in colon cancer.

Dysregulated miRNAs have been demonstrated to be associated with the progression of colon cancer. The dysregulation of miR-3133 was observed in colon cancer, but its specific function was unclear. The functional role of miR-3133 in colon cancer was investigated in this study. A total of 113 colon cancer patients were included. miR-3133 expression was evaluated by PCR. The biological effects of miR-3133 in colon cancer cells were assessed with the help of the transwell and CCK8 assay. The prognostic value of miR-3133 was estimated by a series of statistical analyses. In mechanism, the interaction between miR-3133 and RUFY3 was evaluated by luciferase reporter. The significant downregulation of miR-3133 was observed in colon cancer, which showed a significant association with the advanced TNM stage and bad survival of patients. miR-3133 and TNM stage were identified as independent prognostic indicators of colon cancer. In vitro, the overexpression of miR-3133 exerted a dramatically inhibitory effect on cellular processes of colon cancer, which were enhanced by miR-3133 knockdown. Additionally, miR-3133 could negatively regulate the luciferase activity and expression of RUFY3, which was speculated as the underlying mechanism mediating the regulatory effect of miR-3133. miR-3133 functioned as a prognostic biomarker indicating the progression and prognosis of colon cancer, and it also served as a tumor suppressor via negatively regulating RUFY3, which provides a potential therapeutic target for colon cancer.