CYP24A1 and cancer: Coumarin-based inhibitors, particularly 7-hydroxycoumarin derivatives and substituted analogues, were shown to be endowed with a good selectivity profile, demonstrating nanomolar inhibition of hCA IX and XII, and a much lower potency against hCA I and II, with some representative compounds demonstrating also cytotoxic activity in cancer cells [16,17,18,19,20].