FIBP (FGF1 intracellular binding protein) is a nuclear protein that mediates fibroblast growth factor signaling pathways and plays diverse roles in cellular function and disease. The protein is evolutionarily conserved and encoded by a gene located at chromosome 11.1 1. FIBP functions as a negative regulator of T cell effectiveness in tumor environments, where its knockout enhances CD8+ T cell-mediated cancer killing by reducing cholesterol metabolism that normally inhibits effector T cell function 2. In lung adenocarcinoma, FIBP promotes cancer progression and radioresistance by interacting with transcription factor STAT3 to induce EME1 expression 3. The protein also contributes to Alzheimer's disease risk through immune cell-specific mechanisms, with reduced FIBP expression in peripheral immune cells being protective 45. Disease-causing mutations in FIBP result in Thauvin-Robinet-Faivre syndrome, an autosomal recessive overgrowth disorder characterized by intellectual disability, developmental delay, and tumor predisposition including Wilms tumor 67. Patient fibroblasts with FIBP mutations show increased proliferation capacity, explaining the overgrowth phenotype, while embryonic expression patterns suggest roles in cognitive development 6. These findings establish FIBP as a multifunctional regulator of cell growth, immune responses, and cancer biology.