RHOA and cancer: RhoA is a well-studied Rho GTPase and has long been implicated in malignant transformation, tumor invasion and metastasis.3,21 Activating RhoA mutations are found in a subset of diffuse-type gastric cancer and lymphoma but very rare in most human cancers.22 Therefore, inactivating mutations in the negative regulators of RhoA may represent alternative ways to achieve constitutive activation of RhoA.