GAS7 (growth arrest specific 7) is a cytoskeleton regulator with multifaceted roles in cellular differentiation and disease pathogenesis. Primary Function: GAS7 promotes morphological differentiation of neural cells and regulates cytoskeletal reorganization 1. The protein contains an SH3 domain in its longest isoform (hGas7c) that mediates protein-protein interactions through a non-canonical ligand-binding mode 1. Mechanism: GAS7 participates in neural development and chondrogenic differentiation through ERK1/2 and SOX9 signaling pathways 2. In hepatocellular carcinoma, GAS7 suppresses the PI3K/Akt pathway, inhibiting cell proliferation and enhancing chemotherapy sensitivity 3. GAS7 is also upregulated in activated hepatic stellate cells during metabolic dysfunction-associated steatohepatitis, where it drives myofibroblast transdifferentiation 4. Disease Relevance: Genetic variants in GAS7 associate with primary open-angle glaucoma (POAG); the rs9913911 SNP risk allele increases glaucoma susceptibility and likelihood of requiring surgical intervention 56. The GAS7 locus shows interaction with cannabis exposure in modulating intraocular pressure 7. Low GAS7 expression correlates with poor survival in hepatocellular carcinoma patients 3. Clinical Significance: GAS7 represents a potential prognostic biomarker and therapeutic target for glaucoma, hepatocellular carcinoma, and liver fibrosis.