Targeting histone demethylases KDM5A and KDM5B in AML cancer cells: A comparative view.

Epigenetic modifications play an important role in initiation and progression of cancers including acute myeloid leukemia. Among different epigenetic modifiers, lysine specific demethylases have been noticed as potential therapeutic targets. KDM5 family of histone demethylases which removes methyl marks from lysine residues of H3, are frequently found in the promoter region of transcriptionally active genes resulting in repression of expression. Here we have compared the effects of KDM5A and KDM5B downregulation on HL-60 cell line behavior. KDM5A/5B knockdown resulted in lower viability of HL-60 cells in addition to modified cell cycle distribution and sub-G1 accumulation. Induction of apoptosis was observed in both knockdown cells. But in spite of similarity in their role, downregulation of KDM5A showed more efficient anti-leukemic effects in comparison to KDM5B. Cells showed higher accumulation in sub-G1 and apoptosis occurred significantly higher and also earlier after KDM5A reduction. Expression analysis confirmed almost 5 and 4 fold increased expression for bax and caspase-3 after downregulation of KDM5A in comparison to KDM5B. Due to the present study we propose KDM5A as a potential target for therapeutic aspects of acute myeloid leukemia although further investigations are needed.