CYP24A1 and neoplasm: Interestingly, target coumarins potently inhibited both tumour-related isoforms hCA IX (KIs: 14.7–82.4 nM) and hCA XII (KIs: 5.9–95.1 nM), whereas the cytosolic off-target hCA I and II isoforms have not inhibited by all tested coumarins up to 100 μM.