CDKN1C and neoplasm: The modest decrease in HES1 tumor mRNA but robust increase in CDKN1C as measured by the nCounter experiment (Fig. S12F,G) likely reflects tumor cell heterogeneity, i.e., some RMS cells become resistant to the shRNA and continue dividing as the xenograft experiment progresses as we have seen previously [47], while others cease dividing and express CDKN1C.