DNA Methylation Characterization of Fusion-Positive and Fusion-Negative Rhabdomyosarcoma

Rhabdomyosacoma (RMS) is a common pediatric soft tissue tumor that is associated with the skeletal muscle lineage. RMS comprises two major subtypes: fusion-positive (FP, most commonly PAX3-FOXO1 or PAX7-FOXO1) and fusion-negative (FN, frequently associated with mutations in RAS pathway). Our previous study demonstrated that FP and FN tumors exhibit distinct DNA methylation profiles. In this study, further investigation of genome-wide DNA methylation profiles in RMS tumors revealed DNA methylation differences between AX3-FOXO1 and PAX7-FOXO1 subsets in FP RMS, and between RAS mutation and RAS wild-type subsets in FN RMS. These data provide new insight into the relationship of DNA methylation with mutational changes and transcriptional organization in FP and FN RMS.