miR-873 inhibits colorectal cancer cell proliferation by targeting TRAF5 and TAB1

MicroRNA-873 (miR-873) has been reported to be dysregulated in a variety of malignancies, however, the biological function and underlying molecular mechanism of miR-873 in colorectal cancer (CRC) remain unclear. In the present study we found that the expression levels of miR-873 were markedly decreased in CRC cell lines and tissues from patients. Statistical analysis revealed that miR-873 expression was inversely correlated with the disease stage of CRC. Kaplan-Meier survival analysis revealed that patients with CRC with lower miR-873 expression had shorter overall survival rates. Additionally, downregulation of miR-873 enhanced the proliferation of CRC cells, while upregulation of miR-873 reduced this proliferation. Furthermore, we found that tumor necrosis factor (TNF) receptor-associated factor 5 (TRAF5) and TGF-beta activated kinase 1 (MAP3K7) binding protein 1 (TAB1) were direct targets of miR-873 in CRC cells. A luciferase assay revealed that ectopic expression of miR-873 significantly reduced nuclear factor B (NF-kappa B) luciferase activity, while ectopic expression of miR-873 inhibitor enhanced luciferase activity, suggesting that downregulation of miR-873 can activate NF-kappa B signaling. Therefore, our findings established a tumor-suppressive role for miR-873 in the inhibition of CRC progression, which may be employed as a novel prognostic marker and as an effective therapeutic target for CRC.