MicroRNA-302a enhances 5-fluorouracil-induced cell death in human colon cancer cells

New therapeutic strategies are needed for colorectal cancer (CRC) treatment. MicroRNAs are involved in cancer-pertinent cellular processes, including chemoresistance. As miR-302a is an embryonic stem cell-specific microRNA, studies on miR-302a have focused on its role in human stem cells. Studies analyzing miR-302 function in cancer are limited. In this study, we used two human colon cancer cell lines, HCT116 and HT29, and evaluated the influence of miR-302a on 5-fluorouracil (5-FU)-induced cell death and viability inhibition. With bioinformatics tools, we hypothesized that insulin-like growth factor-1 receptor (IGF-1R) is a novel target of miR-302a, which we confirmed using a luciferase reporter assay and immunoblotting. Then, we designed siRNA against IGF-1R and found that si-IGF-1R resembled the effect of miR-302a on 5-FU treatment. Both miR-302a and si-IGF-1R inhibited Akt signaling. In conclusion, miR-302a targeted IGF-1R and enhanced 5-FU-induced cell death and viability inhibition in human colon cancer cells. Targeting miR-302a may offer new therapeutic interventions in CRC.