Ras-related C3 botulinum toxin substrate 1 (RAC1), Ras homolog family member A (RHOA) and cell division control protein 42 homolog (CDC42), which are the most important and extensively studied members of Rho GTPases, have been identified to regulate actin cytoskeleton reorganization, migration, and metastasis and promote the development of lung cancer [8–11]. The gene discussed is CDC42; the disease is lung cancer.