RHOJ and neoplasm: CDC42 GTPases (CDC42, RHOJ, and RHOQ)are small guanosine triphosphate(GTP)-binding proteins that are known to regulate tumor growth, angiogenesis,metastasis, and cell resistance to targeted therapies.1−5 CDC42 GTPases are essential molecular switches within the cell.Their active/inactive state depends on whether they are bound to GTPor guanosine diphosphate (GDP).6 When CDC42GTPases are bound to GTP, they change their structural conformation,allowing protein surface interactions that are complementary to theirdownstream effectors.