Modulation of cholesterol metabolism affects tumor growth in hamsters.

: To investigate the effects of cholesterol and cholesterol-lowering agents on cholesterol metabolism and tumor growth, 0.5% cholesterol, 2% cholestyramine, or 0.01% simvastatin was fed to hamsters with transplanted Simian virus40 transformed tumor cells. Tumor weight, tissue cholesterol and DNA concentrations, and HMG-CoA reductase activities were determined. Cholesterol or cholestyramine feeding did not affect the tumor growth, however, the tumor weight and DNA concentration were decreased and tumor HMG-CoA reductase activity was increased in the simvastatin group. In conclusion, simvastatin may inhibit the DNA synthesis and growth of the Simian virus40 transformed tumor cells possibly through the inhibition of cholesterol and isoprenoids synthesis in the hamster.