CDKN1A and breast cancer: The present study was designed to determine the possible impact of hepatitis C virus (HCV) infection on the expression of telomerase (TERT), retinoblastoma (RB1), E2F3, TP53, CDKN1A (p21) and fibroblast growth factor receptor- 3 (FGFR3) genes in patients with bladder cancer (BC).