FGF12 is an intracellular fibroblast growth factor belonging to the FHF subfamily, located on chromosome 3 and expressed abundantly in excitable cells 1. Its primary function involves regulating neuronal sodium channel activity, particularly through interaction with voltage-gated sodium channels SCN8A, NaV1.2, and NaV1.6, where it promotes neuronal excitability by modulating fast inactivation kinetics 23. Beyond neural function, FGF12 regulates diverse cellular processes including macrophage activation, keratinocyte proliferation, and cardiac fibroblast activation through distinct signaling pathways 456. In macrophages, FGF12 promotes pro-inflammatory activation via the JAK-STAT pathway and MCP-1/CCR2 axis, driving liver and cardiac fibrosis progression 46. In keratinocytes, FGF12 suppresses p53 signaling by stabilizing MDM2, enhancing proliferation in psoriasis 5. FGF12 is clinically significant in developmental and epileptic encephalopathy, where both loss-of-function biallelic variants and gain-of-function heterozygous variants cause disease through altered sodium channel regulation 23. Additionally, FGF12 overexpression correlates with fibrosis severity in liver and heart diseases and serves as a prognostic biomarker in endometrial stromal sarcoma 4678. These findings position FGF12 as a potential therapeutic target for fibrotic and neurological disorders.