Type C Niemann-Pick disease fibroblasts and their transformed cell lines are hypersensitive to HMG-CoA reductase inhibitors.

The deficiency of exogenous cholesterol transport within fibroblasts of Niemann-Pick disease type C (NPC) has been addressed. In this report we confirmed that the endogenous synthesis of cholesterol within cells was markedly increased in NPC fibroblasts and those transformed by origin-defective simian virus 40. The transformed fibroblasts and those of the primary culture were hypersensitive to 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors as a consequence of their dependence on endogenous cholesterol biosynthesis. The transformed fibroblasts should help further biochemical and genetic research in this condition.