The results illustrate that human prostate cancer frequently show both increased H(2)O(2) and Nox1, and that in an animal model system increased Nox1/H(2)O(2) correlates with increased tumorigenicity.

No abstract

We report a previously unrecognized prostate-specific protein, PrLZ (prostate leucine zipper), a new member of the Tumor Protein D52 (TPD52) family. The gene for PrLZ was localized at chromosome 8q21.1, a locus most frequently amplified in human prostate cancer. Multiple tissue analyses demonstrated PrLZ predominantly in the prostate gland. Although its expression was enhanced by androgens in androgen receptor-expressing cells, PrLZ was detected in all of the human prostate cancer cell lines, regardless of androgen receptor status. Monoclonal anti-PrLZ antibodies were produced and intense immunohistochemical staining of PrLZ was observed in prostate epithelial cells in intraepithelial neoplasia and prostate cancer, whereas lower-level staining was detected in normal and benign epithelial components of the prostate gland. As the only prostate-specific gene identified in the most frequently amplified genomic region in prostate cancer, PrLZ may be the link between chromosome 8q amplification and malignant transformation of the prostate epithelia.

The aim of this study was to assess the relationship of immunoreactivity of cytokeratin 20 (CK20) and CD44 across the spectrum of urothelial neoplasia using the WHO/ISUP consensus classification. A total of 120 papillary urothelial pTa and pT1 tumors (8 papillomas, 8 neoplasms of low malignant potential, and 42 low-grade and 62 high-grade carcinomas) were immunostained by using CK20 and CD44 antibodies. The relationships of tumor grade, pathologic stage, recurrences, and progression in stage with CK20 and CD44 immunoreactivity were assessed. WHO/ISUP grade correlated with tumor stage (P < 0.005), recurrence (P ‫؍‬ 0.02), and progression in stage (P ‫؍‬ 0.031). Normal urothelium showed CK20 immunoreactivity restricted to a few umbrella cells. Expression of CD44 in normal urothelium was restricted to the basal cell layer. Loss of CD44 immunoreactivity and increasing CK20 positivity were significantly associated with increasing tumor grade and stage (P < 0.005). An inverse relationship was observed in the staining patterns of CK20 and CD44 within individual cases, as well as in the aggregate data, with 79.2% of tumors with CD44 loss showing CK20 positivity (P < 0.001). In conclusion, CK20 and CD44 immunoreactivity are significantly related to the WHO/ISUP grade and to each other, and our data suggest their potential combined utility in predicting biologic behavior in patients with papillary urothelial pTa and pT1 neoplasms.