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.