MTTP is a microsomal lipid transfer protein essential for plasma lipoprotein assembly and secretion. It catalyzes the transport of triglycerides, cholesteryl esters, and phospholipids between phospholipid surfaces 12, functioning as a critical cofactor for apolipoprotein B-containing lipoprotein assembly in hepatocytes (VLDL) and intestinal cells (chylomicrons) 3. Beyond lipid metabolism, MTTP regulates ferroptosis and immune responses, with expression predominantly in macrophages within tumor microenvironments 3. In H. pylori-induced gastritis, MTTP downregulation via DNMT1-mediated methylation promotes inflammation and ferroptosis through reduced GPX4 expression 4. Clinically, MTTP mutations cause abetalipoproteinemia and familial hypobetalipoproteinemia, severe genetic lipid disorders characterized by marked hypolipidemia and malabsorption of fat-soluble vitamins 5. MTTP inhibition by lomitapide effectively reduces LDL cholesterol by 50% in homozygous familial hypercholesterolemia patients resistant to statins, representing a valuable therapeutic approach 6. Emerging evidence indicates MTTP as a pan-cancer prognostic and immunotherapeutic biomarker, with elevated expression correlating with poor prognosis in multiple tumor types 3. Additionally, MTTP genetic polymorphisms associate with hepatic steatosis progression in hepatitis C infection 7.