Colony formation assays revealed that RAC1G12V expression partially attenuated the enhanced metformin sensitivity in PLC-shDOCK1 cells, whereas wild-type RAC1 showed only negligible effects in PLC-shDOCK1 cells (Figs. 3H, and S3C), which indicated that RAC1 activation contributes to shDOCK1-mediated metformin sensitization for cancer cells. Here, RAC1 is linked to cancer.