Effect of finasteride on serum androstenedione and risk of prostate cancer within the prostate cancer prevention trial: differential effect on high- and low-grade disease.

OBJECTIVE: To evaluate the effect of finasteride on serum androst-4-ene-3,17-dione (androstenedione) and its association with prostate cancer risk among subjects who participated in the Prostate Cancer Prevention Trial. METHODS: We analyzed serum androstenedione levels in 317 prostate cancer cases and 353 controls, nested in the Prostate Cancer Prevention Trial, a randomized placebo-controlled trial that found finasteride decreased prostate cancer risk. Androstenedione is the second most important circulating androgen in men besides testosterone and also a substrate for 5α-reductase enzyme. RESULTS: We observed a 22% increase in androstenedione levels compared with the baseline values in subjects who were treated with finasteride for 3 years. This significant increase did not vary by case-control status. Adjusted odds ratio and 95% confidence interval for the third tertile of absolute change in androstenedione levels compared with the first tertile were 0.42 (95% confidence interval, 0.19-0.94) for low-grade (Gleason score <7) cases. Similar results were observed when analyzed using percent change. There were no significant associations between serum androstenedione levels and the risk of high-grade disease. CONCLUSION: The results of this nested case-control study confirm that finasteride blocks the conversion of testosterone to dihydrotestosterone (DHT) and of androstenedione to 5α-androstanedione-3,17-dione, which also leads to the reduction of DHT formation. This decrease in DHT may help reduce the risk of low-grade prostate cancer in men. Our data on a differential effect of androstenedione also suggest that some high-grade prostate cancers may not require androgen for progression.

Individualized medicine for renal cell carcinoma: establishment of primary cell line culture from surgical specimens.

BACKGROUND: The lack of effective "in vivo" and "in vitro" models to predict success of pharmacological therapy for patients with renal cell carcinoma, as well as, the variety of cancer cell types demands the development of better experimental models to understand the pathophysiology of the disease and evaluate drug sensitivity in vitro. PURPOSE: To develop primary renal cancer cell culture irrespective of tumor grade and tumor type, harvested from the patient's pathological specimen immediately after the laparoscopic radical nephrectomy to study potential "in vivo" pharmacological sensitivity. MATERIALS AND METHODS: A total of 24 patients (17 males and 7 females). Mean age of 63.1+/-3.1 y.o. The mean size of the renal masses was 7.56+/-3.1 cm. Normal and pathological renal tissue was collected immediately after the specimen was extracted and submitted to enzymatic digestion for 16-24 hours. Clear cell carcinoma cells were selected through multiple passages in DMEM medium supplemented with glucose and antibiotics. RESULTS: Establishment of cell line culture from all the patients' specimens irrespective of tumor grade and tumor type was achieved successfully. In addition to the tumor cell line culture, normal parenchyma tissue yielded primary cell lines to allow testing the response of tumor types to various pharmacological therapeutic agents and toxicity of such treatments to healthy tissue. From the initial collection of the specimens obtained after the removal of the kidney to the development of cell lines took occurred in average 32+6 hrs. The cells in culture showed characteristics of epithelial cells; like expression on cytokeratin and were maintained in culture for more than 20 passages. CONCLUSION: The development of renal cancer cell cultures in vitro is labor intense but may yield a more realistic model to tailor pharmacological therapies and predict therapeutic success prior to "in vivo" application-a step in the direction of individualized medicine for RCC.