Influence of suramin alone or in combination with DHT and PDGF on the cell proliferation of benign and malignant human prostatic tissues in organ cultures.

We studied the suramin-induced influence on the cell proliferation of 16 benign and 6 malignant lesions of the human prostate maintained in vitro as organ cultures. The cell proliferation was assessed by nuclear labeling with tritiated thymidine autoradiography. We also studied the dihydrotestosterone (DHT)-and platelet-derived growth factor (PDGF)-induced modulation of suramin influence on such prostate organ culture cell proliferation. Our results indicate that more than half of the benign prostatic tissues showed cell proliferation which was modulated by DHT and/or PDGF, while none of the six carcinomas responded to such hormonal stimulation. Suramin alone inhibited the cell proliferation of only 19% of the prostate organ culture under study, while in combination with DHT and/or PDGF this inhibition level reached 48%. However, we occasionally observed that S alone or in combination with DHT and/or PDGF was also able to stimulate prostate cell proliferation. We think that organ cultures of human prostatic tissues might represent a helpful pre-clinical tool to study the anti-tumoral influence of suramin, which is a new antineoplastic generative compound.