In this study, distinct methylation alterations were identified in the 5' flanking region of the MyoD1 gene from the two major subtypes, ie, alveolar and embryonal rhabdomyosarcoma.
Here we report the discovery, through whole-exome sequencing, of a recurrent somatic mutation encoding p.Leu122Arg in the myogenic transcription factor MYOD1 in a distinct subset of ERMS tumors with poor outcomes that also often contain mutations altering PI3K-AKT pathway components.
YAP1-TEAD1 upregulate pro-proliferative and oncogenic genes and maintain the ERMS differentiation block by interfering with MYOD1 and MEF2 pro-differentiation activities.
Here we report the discovery, through whole-exome sequencing, of a recurrent somatic mutation encoding p.Leu122Arg in the myogenic transcription factor MYOD1 in a distinct subset of ERMS tumors with poor outcomes that also often contain mutations altering PI3K-AKT pathway components.
The immunohistochemical analysis was positive for the antigens: MyoD1, myogenin, desmin, and Ki67 (100% positivity in neoplastic cells), allowing the identification of the tumour as an eRMS.
Immunohistochemical stains were positive for vimentin, CD99, myogenin, and MyoD1 consistent with a diagnosis of embryonal rhabdomyosarcoma, botryoid subtype.