Immunohistochemical expression of transforming growth factor beta 1 and nm-23 H1 antioncogene in prostate cancer: divergent correlation with clinicopathological parameters.

BACKGROUND: Prostate cancer is one of the main causes of morbidity and mortality among men. Several oncogenes and growth factors have been studied in an attempt to explain the molecular basis of carcinogenesis and progress of this carcinoma. In this study we correlated the immunohistochemical expression of antioncogene nm-23 H1 and transforming growth factor beta 1 (TGF-beta 1) with the clinical stage, PSA values, Gleason score and survival in prostate cancer. MATERIALS AND METHODS: Fifty nine patients with prostate cancer were evaluated. PSA measurement, Gleason score determination and clinical staging were recorded for all the patients by the time of initial diagnosis and prior to any treatment. Follow-up ranged from 12 to 40 months. Tissue sections from representative areas of the tumors were immunohistochemically stained for nm-23 H1 and TGF-beta 1. The expression of these markers was correlated with stage, PSA values, Gleason score and survival. RESULTS: There was a negative correlation between nm-23 H1 staining and tumor stage and grade. High grade (Gleason score 8-10) and stage D tumors showed weaker staining than low stage and grade tumors. There was a positive correlation between TGF-beta 1 staining, tumor stage and serum PSA levels. Additionally, TGF-beta 1 proved to be a negative predicting factor for patient survival. In tumors expressing both markers, TGF-beta 1 was the one to determine the aggressiveness of the carcinoma. CONCLUSIONS: nm-23 H1 appears to be a tumor suppressor gene in prostate cancer, while TGF-beta 1 may act as a stimulating agent provoking aggressive behavior and metastasis. Their immunohistochemical staining may constitute complementary information in the evaluation of prostate cancer patients.

Determination of interferon-alpha receptors in urothelial cancer and in normal urothelium.

PURPOSE: We determined and compared the presence and frequency of interferon-alpha 2b receptors in urothelial neoplasms and normal urothelium, since the biological activity of interferons becomes apparent only after they bind to specific receptors. MATERIALS AND METHODS: With our method detection of interferon-alpha 2b receptors required a large number of cells, that is more than 1 x 10(6) cells per ml. We studied 14 patients with relatively large tumors of all stages and grades. Three patients had grade I, 4 grade II and 7 grade III disease. As controls we used biopsies of normal urothelium from 14 patients who underwent transvesical prostatectomy. Interferon-alpha 2b receptors were detected quantitatively through the binding of radiolabeled 125iodine human recombinant interferon-alpha 2b in normal and malignant urothelial tissue samples. The interferon-alpha 2b receptors are expressed as receptor sites per cell, and the results were evaluated with Scatchard analysis. RESULTS: The number of interferon-alpha 2b receptor sites per cell ranged from 43 to 100 (mean plus or minus standard deviation 62 +/- 18) in normal urothelium and from 110 to 210 (mean 174 +/- 25) in malignant epithelium. This difference was statistically significant (p < 0.001), Student's t test 13.75). The difference in the number of interferon-alpha 2b receptors in grades I plus II and grade III tumors is suggestive but not statistically significant (p < 0.10, Student's t test 2.075). High grade tumors expressed greater numbers of interferon-alpha 2b receptors than low grade tumors. CONCLUSIONS: The method used needs refining so that it will require fewer cells to determine interferon-alpha 2b receptors. Interferon-alpha 2b receptors are detected in bladder urothelium and are abundant in malignant tissue with increasing frequency as tumor grade increases. If we can establish, in the future, a correlation of the number of interferon-alpha 2b receptors with the potential response of patients to intravesical instillation therapy with interferon, we might have an important prognostic method for selecting subgroups of patients with transitional cell carcinomas who will benefit from interferon-alpha 2b instillation.