Treatment with different combinations of LSD1 and HDAC inhibitors at the same concentrations used for RMS cells (i.e., GSK690/JNJ-26481585, Ex917/JNJ-26481585 or GSK690/SAHA) induced no or little (< 20%) cell death in C2C12 cells (Supplementary Fig. 4A–C), thus pointing to some tumor selectivity. This evidence concerns the gene HDAC9 and neoplasm.