Ph1imatinib: high incidence of thromboembolic events with docetaxel/estramustine combination for CRPC. Ph2 imatinib: limited PSA response, toxicities in biochemical failure patients Ph3 dasatinib: addition of dasatinib to docetaxel did not improve overall survival in mCRPC. Ph3 sunitinib: plus prednisone did not improve OS compared with prednisone alone in docetaxel-refractory mCRPC Ph2 sorafenib: 20% PR mTTP 5.9 mos, mOS 14.6 mos. Ph2 cabozantinib: improvements in bone scans, pain, analgesic use, measurable soft tissue disease, circulating tumor cells, and bone biomarkers, mOS 10.8 mos. Here, KLK3 is linked to neoplasm.