Another study performed on xenograft models using VCaP cells with knocked-down ERG expression (siRNA), showed a significant reduction in tumorigenicity, concomitant reduction in the expression of the oncogene C-MYC and upregulation of prostate epithelial differentiation genes KLK3 and SLC45A3 (Sun et al., 2008), suggesting that ERG overexpression has an oncogenic role in established prostate tumors, by inducing upregulation of C-MYC and repressing prostate epithelial differentiation. This evidence concerns the gene ERG and prostate neoplasm.