CDC42 is a plasma membrane-associated small GTPase that cycles between active GTP-bound and inactive GDP-bound states to regulate diverse cellular processes 1. It functions as a central regulator of actin cytoskeleton dynamics, controlling cell migration, epithelial cell polarization, and filopodia formation in neurons and podocytes 2. CDC42 also regulates spindle microtubule attachment during mitosis and participates in phagocytosis through F-actin organization. In the nervous system, CDC42 mediates dendritic spine structural plasticity and is required for DOCK10/DOCK11-dependent spine formation 2. Clinically, CDC42 dysfunction contributes to multiple pathologies. Loss-of-function DOCK11 mutations impairing CDC42 activation cause severe immune dysregulation, systemic inflammation, and anemia 2. CDC42 deficiency in endometrial stromal cells induces senescence via Wnt pathway activation, impairing uterine receptivity in recurrent implantation failure 3. Conversely, CDC42 overexpression drives malignancy: elevated CDC42 promotes glioma progression through PI3K-AKT pathway activation 4, and CDC42 upregulation in gastric cancer enhances chemotherapy resistance 5. Additionally, CDC42 missense mutations cause autoinflammatory diseases, revealing novel roles in innate immunity 6. CDC42 also regulates vascular leakage through antagonistic interactions with RhoA 7, highlighting its broader inflammatory roles.