Properties of androphilic proteins in cytosols of human benign prostatic hypertrophy.

Androphilic proteins in the cytosol from the human benign prostatic hypertrophy are separated into two fractions by Sephadex chromatography; void volume fraction and IgG fraction which was eluted near the site of hIgG. In the present study, properties of these two androphilic proteins were compared. Association constants of these proteins were in the order of 10(9) M-1. However, the binding capacity of the former was smaller than that of the latter. These two androphilic proteins well bound to nuclei, and the high-affinity and saturable binding to nuclei was observed in the 3H-dihydrotestosterone-IgG fraction complex, while binding of 3H-dihydrotestosterone-void volume fraction complex to nuclei was low affinity and unsaturable. The binding of the complexes to chromatin seems to be of low affinity and nonsaturable. These androphilic proteins did not bind to calf thymus DNA. Salt extractability of the bound void volume fraction after incubation with nuclei was not different from that of the bound IgG fraction. It was observed that the chromatographic behavior of the androphilic protein in IgG fraction was changed after incubation with nuclei.