Aberrant methylation in pediatric myelodysplastic syndrome

Background: Aberrant methylation of gene promoter region is responsible for inappropriate gene silencing, and it has been associated to initiation and progression of cancer. Aberrant promoter methylation is frequently observed in adult patients with myelodysplastic syndrome (MDS), but in pediatric patients it has been poorly investigated. Methods: We examined the promoter methylation status of 13 genes in bone marrow cells collected at diagnosis of 21 pediatric patients with MDS (subtype RAEB or RAEB-t). For this analysis, we performed sodium bisulfite treatment of genomic DNA, followed by methylation specific PCR (MSP). Results: In pediatric MDS samples, we observed two genes frequently methylated: CALCA was methylated in 85.7% (18/21) of the analyzed samples and CDKN2B in 50% (6/12). Conclusions: Our findings indicate that CALCA and CDKN2B are frequently methylated in pediatric MDS. It suggests that aberrant methylation in pediatric MDS seems to be similar to adult MDS, thus pediatric patients could be also benefited with treatment using demethylating agents.