KRAS and colorectal carcinoma: By co-transfecting miR-30b and KRAS in HCT8 and CACO2 cells, western blotting, CCK8 and colony formation assays revealed that compared with the control group, the expression level of KRAS protein, the proliferation ability of CRC cells and the number of colonies in the co-transfection group were significantly increased (Fig. 4c–e).