Carbonic anhydrase II is induced in HL‐60 cells by 1,25‐dihydroxyvitamin D3: A model for osteoclast gene regulation

Carbonic anhydrase II (CA II) generates the H+ required for osteoclast‐mediated bone resorption in humans. We have developed the human promyelocytic cell line HL‐60 as a model system with which to study the osteoclast‐specific expression of the CA II gene. Treatment of the cell line with 1,25‐dihydroxyvitamin D3 resulted in a dramatic de novo induction of CA II at both the protein and mRNA levels. CA II mRNA was also induced to a lesser extent by 12‐O‐tetradecanoyl phorbol 13‐acetate. Treatment with dimethyl sulfoxide did not increase CA II mRNA. These findings indicate that the HL‐60 cell line will be a useful model system to study the osteoclast‐specific expression of the CA II gene.