Rhabdomyosarcoma: Molecular analysis of Igf2, MyoD1 and Myogenin expression

Rhabdomyosarcoma is the most common soft tissue sarcoma of childhood. There are two major histopathological types of RMS - embryonal (eRMS) and alveolar (aRMS). A molecular study of Igf2, MyoD1 and Myogenin was performed to determine the expression profiles and to assess the possible utility of these genes as potential treatment targets. Patients with RMS showed up to 100-fold increase of Igf2 transcription in comparison with normal skeletal muscle. Our data suggest that overexpression of Igf2 occurs in RMS of both histological subtypes. No correlation between the results of Igf2 mRNA expression and LOH at the 11p15 region (p=0.12) was observed, but there was a trend of a higher expression of Igf2 mRNA in RMS samples with LOH. We observed a high level of MyoD1 mRNA in both aRMS and eRMS, and we detected a similar level of MyoD1 mRNA in RMS and normal skeletal muscles. There was a correlation between the results of MyoD1 mRNA expression and LOH at the 11p15 region. We did not observe any statistical difference in the level of Myogenin mRNA in the subgroups of RMS. Analogous to MyoD1, we observed a similar level of Myogenin mRNA in RMS and normal skeletal muscles.