The Partial Dependency of Human Prostatic Growth Factor on Steroid Hormones in Stimulating Thymidine Incorporation into Dna

Abstract Growth factors stimulating DNA synthesis in mouse 3T3, human DU145, and LNCaP were partially purified from human benign hyperplastic and cancerous prostates. These factors have a high affinity for heparin sepharose and are eluted from the heparin-sepharose column, at 1.2 to 1.9 M NaCl. In normal prostates, the high affinity human prostatic growth factor occurred only in extremely small amounts. The high affinity growth factors stimulate DNA synthesis in 3T3, DU145, and LNCaP. Stimulation was significantly enhanced by 5 α -dihydrotestosterone and 17 β -estradiol in the androgen sensitive LNCaP cell line. SDS-PAGE and isoelectrofocusing confirmed that the partially purified factors had a molecular weight of 18 kDa and acidic isoelectric points of pH 3.6 and 4.7.