D- and L-2HG inhibited KDM5B-catalyzed demethylation with IC50 values in a range of 150–200 μM, that is, less potently than for some other reported histone demethylases (e.g., KDM4A, the IC50 values for both D- and L-2HG ~ 25 μM) [28]; these values, however, do not exclude inhibition in tumor cells where D-2HG levels can reach the mM range [46]. This evidence concerns the gene KDM5B and neoplasm.