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Purpose: The nuclear transcription factor nuclear factor-kappa B (NF kappa B) and its inhibitor, I kappa B, regulate the transcription of various genes involved in cell proliferation, adhesion, and survival. The NF kappa B transcription factor complex plays a role in cancer development and progression through its influence on apoptosis. More recently, NF kappa B has been shown to be activated in human and androgen-independent prostate cancer cells. To our knowledge, this is the first study demonstrating the prognostic significance of NF kappa B immunoreactivity in prostate adenocarcinomas (PACs)., Experimental Design: Using prostatectomy specimens, we performed immunohistochemical staining for NF kappa B and I kappa B alpha (Santa Cruz Biotechnology) on formalin-fixed, paraffin-embedded sections obtained from 136 patients with PAC. Cytoplasmic and nuclear immunoreactivity was scored for intensity and distribution, and results were correlated with preoperative serum prostate-specific antigen, tumor grade, stage, DNA ploidy (Feulgen spectroscopy), and biochemical disease recurrence., Results: Forty-nine percent of PACs overexpressed cytoplasmic NF kappa B, and 63% showed decreased I kappa B expression. Cytoplasmic NF kappa B overexpression correlated with advanced tumor stage (P = 0.048), aneuploidy (P = 0.022), and biochemical disease recurrence (P = 0.001). When we compared the means for the NF kappa B-positive and -negative subgroups, NF kappa B overexpression correlated with preoperative serum prostate-specific antigen (P = 0.04) and DNA index (P = 0.05). Fifteen percent of PACs expressed nuclear NF kappa B, which correlated with high tumor grade (P = 0.001) and advanced stage (P = 0.05). Decreased I kappa B alpha expression correlated with high tumor grade (P = 0.015). On multivariate analysis, tumor stage (P = 0.043) and NF kappa B overexpression (P = 0.006) were independent predictors of biochemical recurrence., Conclusion: These results support a role for NF kappa B pathway proteins in the tumorigenesis of PACs. The findings are also consistent with reported experimental studies suggesting a new strategy of combined chemotherapy and specific NF kappa B blockade in decreasing the rate of disease relapse.

Purpose: The restricted expression of the surface glycoprotein prostrate-specific membrane antigen (PSMA) to normal prostate tissue, primary and metastatic prostate cancer (PCa), and the neovasculature of various nonprostatic epithelial malignancies has enabled targeting strategies for PCa treatment using anti-PSMA antibodies., Experimental Design: Using prostatectomy specimens, immunohistochemical staining for PSMA (7E11 antibody) was performed on formalin-fixed paraffin-embedded sections of 136 cases of PCa. Cytoplasmic immunoreactivity was scored for intensity and distribution, and results were correlated with tumor grade, pathological stage, DNA ploidy status (Feulgen spectroscopy), and disease recurrence. PSMA mRNA expression in selected primary tumors and metastatic lesions was also detected using in situ hybridization and autoradiography., Results: Generally, PCa cells expressed relatively increased levels of PSMA as compared with benign elements. Among the PCa cases, increased (high) PSMA expression correlated with tumor grade (P = 0.030), pathological stage (P = 0.029), aneuploidy (P = 0.010), and biochemical recurrence (P = 0.001). The mean serum prostate-specific antigen level of 18.28 ng/ml at the time of diagnosis for the PSMA-overexpressing tumors was significantly greater than the mean serum prostate-specific antigen of 9.10 ng/ml for the non-PMSA-overexpressing group (P = 0.006). On multivariate analysis, pathological stage (P = 0.018) and PSMA expression (P = 0.002) were independent predictors of biochemical recurrence. PSMA protein overexpression in high-grade primary PCa tumors and metastatic lesions also correlated with increased PSMA mRNA expression levels using in situ hybridization and autoradiography., Conclusions: This study demonstrates for the first time that overexpression of PSMA in primary PCa correlates with other adverse traditional prognostic factors and independently predicts disease outcome.

Transforming growth factor alpha-Pseudomonas exotoxin-40 (TP40) is a hybrid fusion protein that selectively binds to cancer cells that express the epidermal growth factor receptor. TP40 is then internalized and kills these cells by virtue of its Pseudomonas exotoxin-derived domains. We studied the safety and short-term antitumor activity of intravesical TP40 in 43 patients with refractory superficial bladder cancer. These patients had resected Ta/T1 disease (n = 19), visible Ta or T1 lesions (n = 11), or carcinoma in situ (n = 13). Patients were treated with increasing dose levels of TP40 at 0.15, 0.3, 0.6, 1.2, 2.4, 4.8, or 9.6 mg/week for 6 weeks and evaluated by comparing pretreatment and posttreatment cystoscopic examinations, cytology, and histopathology. All TP40 doses were well tolerated. No evidence of antitumor activity was seen in any of the patients with Ta or T1 lesions. However, 8 of 9 patients with evaluable carcinoma in situ were judged by histopathology of multiple biopsy specimens to exhibit clinical improvement following TP40 therapy. In most of these responsive patients, cystoscopic examination supported the histopathological findings, although cytology of urine and bladder washings persistently demonstrated malignant cells. Therefore, TP40 appears to be a well-tolerated biological agent that may prove to have utility in treating carcinoma in situ of the bladder.