KLK3 and prostate cancer: Following the discovery that miR-141 is elevated in prostate cancer and correlates with the serum PSA levels [164], a number of other microRNAs were found to be up-regulated (e.g., miR-20a, miR-21, miR-195 and miR-375) or down-regulated (e.g., miR-34a, miR-143/145, miR-205 and miR-488) in prostate cancer (for recent reviews see [28,165].