MiR-22 regulates 5-FU sensitivity by inhibiting autophagy and promoting apoptosis in colorectal cancer cells

Autophagy has become one of the most important mechanisms of chemotherapy resistance by supporting the survival of tumor cells under metabolic and therapeutic stress. Here, we showed that miR-22 inhibited autophagy and promoted apoptosis to increase the sensitivity of colorectal cancer (CRC) cells to 5-fluorouracil (5-FU) treatment both in vitro and in vivo. B-cell translocation gene 1 (BTG1) was identified as a new target of miR-22, which could reverse the inhibition of autophagy induced by miR-22. Thus, miR-22 may function as an important switch between autophagy and apoptosis to regulate 5-FU sensitivity through post-transcriptional silencing of BTG1. Promisingly, miR-22 could be considered as both a predictor of 5-FU sensitivity for personalized treatment and a therapeutic target for colorectal cancer.