CPSF1 and Familial prostate cancer: To confirm an important role for CPSF1 in regulating the growth of prostate cancer cells and rule out off-target effects from screening with siRNA pools, we used two independent lentivirus short hairpin RNAs (shRNAs) to stably knockdown CPSF1 in LNCaP, LNCaP95, and 22Rv1 cells and the benign epithelial prostate cell line RWPE-1 (Figures 2F–2I).