5 hepatoma cells. These cells express CYP27B1, the gene encoding for the enzyme responsible for the synthesis
of the vitamin-D hormonally active metabolite, calcitriol. Treatment with vitamin-D(3) resulted in calcitriol production and induction of calcitriol target gene CYP24A1, indicating that these cells contain the full machinery for vitamin-D metabolism and activity. Notably, treatment with calcitriol resulted in HCV inhibition.