FABP1 (fatty acid binding protein 1) is a cytosolic lipid carrier that binds free fatty acids, cholesterol, and their coenzyme A derivatives, playing central roles in hepatic and intestinal lipid metabolism 1. In the liver, FABP1 mediates lipoprotein-mediated cholesterol uptake and intracellular lipid transport 2. Mechanistically, FABP1 functions through interaction with peroxisome proliferator-activated receptors (PPARα/γ), regulating fatty acid uptake and oxidation 3. In enterocytes, FABP1 is essential for dietary fatty acid absorption, basolateral secretion, and chylomicron assembly, while also supporting cell proliferation 4. Dysregulation of FABP1 is implicated in multiple pathologic conditions. FABP1 overexpression in tumor-associated macrophages promotes hepatocellular carcinoma progression through PPARG/CD36-mediated fatty acid oxidation, with orlistat-mediated FABP1 inhibition synergizing with anti-PD-1 immunotherapy 5. In renal cell carcinoma, FABP1+ tumors drive angiogenesis via the PLG-PLAT axis under fatty acid reprogramming 6. Conversely, FABP1 downregulation via PPARα suppression contributes to IgA nephropathy-associated ferroptosis in mesangial cells 7. The human FABP1 T94A polymorphism is associated with dyslipidemias and NAFLD 1. These findings establish FABP1 as a therapeutic target across metabolic and malignant diseases.