RAC1 and breast cancer: More investigations have revealed that Rac-dependent cell signaling activation can promote cell adhesion, migration, invasion and metastasis in a variety of cancers, such as prostate cancer, breast cancer, hepatocellular carcinoma, colon carcinoma and renal carcinoma, suggesting that Rac1 plays an important role in tumorigenesis and carcinoma progression [31], [34], [35].