The fusion index (# nuclei in MyHC+ cells/# myocytes) was reduced ~60% by PC-3 medium and ~30% by DU145 medium as compared to controls (Fig 2C), The differentiation index (#nuclei in MyHC+ cells/total nuclei) was reduced approximately 40% in cells pre-treated with PC-3 medium, and ~30% for those treated with DU145 medium, as compared to controls (Fig 2C), suggesting that both the number and maturity of the myotubes was affected by a brief exposure to tumor-conditioned medium. This evidence concerns the gene MYH6 and neoplasm.