RAC1, a member of the Rho family of small GTPases that acts as molecular switch through GDP-bound inactive and GTP-bound active states and regulates a wide range of cellular processes, including cell proliferation, differentiation, survival, motility, nuclear and cytoskeleton assembly, was recently reported that its nuclear translocation associates with carcinogenesis and enhanced aggressiveness of cancer. This evidence concerns the gene RAC1 and cancer.