CYP24A1 and colorectal carcinoma: Additionally, we also found that the expression of CYP24A1, the main enzyme determining the biological half-life of calcitriol, was significantly inhibited by miR-1278, according to data from clinical, RNA-seq and functional assays, which allowed miR-1278 to sensitize CRC cells to vitamin D. In summary, our data demonstrated that miR-1278 may serve as a potential tumor suppressor gene and biomarker for determining sensitivity to oxaliplatin and vitamin D in CRC.