While studies on how RAC1 and RAC1B contribute to chemotherapy resistance and targeted therapy resistance in CRC are scarce, RAC1 has been shown to be involved in therapy resistance in other cancers such as breast cancer, melanoma, prostate cancer, pancreatic cancer, and others [106,107,108,109,110,111,112,113,114]. This evidence concerns the gene RAC1 and breast carcinoma.