DNA Methyltransferase Inhibitors Show Potential in Leukemia Treatment

Researchers at Himeji Dokkyo University have conducted a study on the effects of DNA methyltransferase inhibitors (DNMT inhibitors) in treating high-risk myelodysplastic syndromes (MDS) and leukemia. According to the study, DNMT inhibitors such as decitabine (DAC) induce hypomethylation of the promoter region of the cholesterol 25-hydroxylase (CH25H) gene, leading to increased expression of CH25H and subsequent production of 25-hydroxycholesterol (25-OHC). This, in turn, activates the CH25H-oxysterol pathway, resulting in apoptotic cell death of leukemic cells.

Key Takeaways:

• DNMT inhibitors, such as decitabine (DAC), can induce hypomethylation of the CH25H gene promoter region in MDS/leukemia cell lines.
• This hypomethylation leads to increased expression of CH25H and subsequent production of 25-OHC, which activates the CH25H-oxysterol pathway.
• Activation of the CH25H-oxysterol pathway results in apoptotic cell death of leukemic cells.
• Normal CD34-positive cells show hypomethylated status of the CH25H gene promoter region.
• Exogenous addition of 25-OHC suppresses leukemic cell growth.
• The study suggests that DNMT inhibitors may activate the CH25H-oxysterol pathway by their hypomethylating mechanism and induce leukemic cell death.
• Further investigations of the promoter analysis of CH25H gene and therapeutic effects of DNMT inhibitors on MDS/leukemia are warranted.

Statistics:

• 25-OHC production is increased after DAC treatment in vitro (Scientific Reports, 2015;5():9-20).
• 25-OHC is produced at high levels in leukemic cells treated with DAC (Scientific Reports, 2015;5():9-20).
• Leukemic cell growth is suppressed after exogenous addition of 25-OHC (Scientific Reports, 2015;5():9-20).

Sources:

• Five-aza-2 '-deoxycytidine-induced hypomethylation of cholesterol 25-hydroxylase gene is responsible for cell death of myelodysplasia/leukemia cells. Scientific Reports, 2015;5():9-20.