Signaling pathways regulated by Rho-like proteins.

Small GTP-binding proteins of the Rho-subfamily, including Cdc42, Rac1 and RhoA, are key control molecules in the reorganization of the actin cytoskeleton induced by growth factors. Recent studies indicate that signal transduction pathways regulated by Rho-like GTPases are interconnected with the Ras-Raf-MAPkinase pathway, and play a role in several kinase pathways that lead to transcriptional activation and oncogenic transformation. Moreover, pathways regulated by Rac are involved in the acquisition of invasive and metastatic capacity of tumor cells. Aberrations in signaling pathways controlled by Rho-like GTPases may thus have consequences for tumor progression and metastasis.