To examine the effects of Pim1 overexpression on prostate tumorigenesis, we selected three human prostate cell lines at different cancer disease stages: RWPE1, an immortalized, benign, androgen-responsive human prostatic epithelial cell line [29]; LNCaP, a tumorigenic, androgen-responsive human prostate cancer cell line [30,31]; and DU145, a tumorigenic androgen-independent human prostate cancer cell line [32-34]. This evidence concerns the gene PIM1 and cancer.