IGF2 and benign prostatic hyperplasia: Interestingly, by considering all prostate tumors together without a separation in TUR-BPH, RP-BPH and RP-PCa, we found a highly significant correlation between KLF4 and IGF2 expression (p < 0.0001, Spearman’s rank correlation coefficient r = 0.668) (Fig. 7d).