Alternatively, reduction of global DNA methylation levels by 5-aza may render the T-ALL epigenome more responsive to the enhancing effect of vitamin C on histone demethylases, since vitamin C has been shown to act as a cofactor for several Jumonji-catalytic-domain–containing histone demethylases such as KDM2A-B (H3K36me), KDM3A (H3K9me), KDM4A-E (H3K36me and H3K9me), and KDM6A-B (H3K27me) (70). Here, KDM4A is linked to acute lymphoblastic leukemia.