Rac1 is thought to play a significant role in the development of various cancers, including melanoma (1) and non-small cell lung cancer(2). Rac1 is a small (~21 kDa) signaling G protein (more specifically a GTPase) and is a member of the Rac subfamily of the family Rho family of GTPases. Members of this superfamily appear to regulate a diverse array of cellular events, including the control of cell growth, cytoskeletal reorganization, and the activation of protein kinases Rac1 is a pleiotropic regulator of many cellular processes, including the cell cycle, cell-cell adhesion, motility (through the actin network), and of epithelial differentiation [1][2][3].