RHO and cancer: Approximately 20% of human cancers harbour Ras subfamily mutations, which maintain Ras in a constitutively active GTP-binding conformation and subsequently overactivate downstream signalling to mediate tumorigenesis.266 In addition, other small G proteins, such as Rho, Rab and Arf subfamilies, are overexpressed in a variety of cancers and promote tumorigenesis by influencing intracellular regulatory processes.266 These molecules need to undergo prenylation to ensure their proper subcellular localisation to the PM and/or endomembranes before performing their oncogenic functions.