Mutations in the mtDNA have been found to fulfill all of the criteria expected for pathogenic mutations causing prostate cancer. Focusing on the cytochrome oxidase subunit I (COI) gene, we found that 11-12% of all prostate cancer patients harbored COI mutations that altered conserved amino acids (mean conservation index ‫؍‬ 83%), whereas <2% of no-cancer controls and 7.8% of the general population had COI mutations, the latter altering less conserved amino acids (conservation index ‫؍‬ 71%). Four conserved prostate cancer COI mutations were found in multiple independent patients on different mtDNA backgrounds. Three other tumors contained heteroplasmic COI mutations, one of which created a stop codon. This latter tumor also contained a germ-line ATP6 mutation. Thus, both germ-line and somatic mtDNA mutations contribute to prostate cancer. Many tumors have been found to produce increased reactive oxygen species (ROS), and mtDNA mutations that inhibit oxidative phosphorylation can increase ROS production and thus contribute to tumorigenicity. To determine whether mutant tumors had increased ROS and tumor growth rates, we introduced the pathogenic mtDNA ATP6 T8993G mutation into the PC3 prostate cancer cell line through cybrid transfer and tested for tumor growth in nude mice. The resulting mutant (T8993G) cybrids were found to generate tumors that were 7 times larger than the wild-type (T8993T) cybrids, whereas the wild-type cybrids barely grew in the mice. The mutant tumors also generated significantly more ROS. Therefore, mtDNA mutations do play an important role in the etiology of prostate cancer.cybrid ͉ oxidative phosphorylation ͉ inherited predisposition

No abstract

Although bladder cancers are very common, little is known about their molecular pathogenesis. In this study, invasive bladder cancers were evaluated for the presence of gene mutations in the p53 suppressor gene. Of 18 tumors evaluated, 11 (61 percent) were found to have genetic alterations of p53. The alterations included ten point mutations resulting in single amino acid substitutions, and one 24-base pair deletion. In all but one case, the mutations were associated with chromosome 17p allelic deletions, leaving the cells with only mutant forms of the p53 gene products. Through the use of the polymerase chain reaction and oligomer-specific hybridization, p53 mutations were identified in 1 to 7 percent of the cells within the urine sediment of each of three patients tested. The p53 mutations are the first genetic alterations demonstrated to occur in a high proportion of primary invasive bladder cancers. Detection of such mutations ex vivo has clinical implications for monitoring individuals whose tumor cells are shed extracorporeally.

No abstract

Of 35 patients with 48 angiomyolipomas 24 patients were followed clinically to determine the natural history of angiomyolipoma. Average patient age at presentation was 50 years (range 17 to 74) and of the patients 94% were women, 17% had tuberous sclerosis and 25% overall had bilateral disease. The patients could be divided into 2 distinct groups based on tumor size of 4 cm. or less and greater than 4 cm. Those with tumors less than 4 cm. were less likely to be symptomatic (24%) and patients with angiomyolipomas greater than 4 cm. were more often symptomatic (52%). No surgery was required for tumors less than 4 cm. but for 30% of the tumors greater than 4 cm. surgical intervention was necessary. Unlike any previously reported large series this study included radiological and historical followup available for 24 patients with angiomyolipoma with a mean followup time of 4 years (range 0.5 to 14). Moreover, to our knowledge we report for the first time documented growth during the study period of 27% of angiomyolipomas less than 4 cm. (4 of 15 tumors) and 46% of angiomyolipomas greater than 4 cm. (6 of 13 tumors). All patients with tumors less than 4 cm. were asymptomatic and only 1 required surgery. In contrast, tumors greater than 4 cm. were more frequently symptomatic (46%) and required surgery (54%). Patients with tuberous sclerosis and angiomyolipomas were distinctly different from patients with angiomyolipoma only, since they tended to present at a younger age, had a higher incidence of bilateral renal involvement, were more symptomatic, had larger tumors that were more likely to grow, and frequently required surgery. Based on this study, a modified approach to the current management of angiomyolipoma is recommended.

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.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) gene-transduced, irradiated tumor vaccines induce potent, T-cell-mediated antitumor immune responses in preclinical models. We report the initial results of a Phase I trial evaluating this strategy for safety and the induction of immune responses in patients with metastatic renal cell carcinoma (RCC). Patients were treated in a randomized, double-blind dose-escalation study with equivalent doses of autologous, irradiated RCC vaccine cells with or without ex vivo human GM-CSF gene transfer. The replicationdefective retroviral vector MFG was used for GM-CSF gene transfer. No dose-limiting toxicities were encountered in 16 fully evaluable patients. GM-CSF gene-transduced vaccines were equivalent in toxicity to nontransduced vaccines up to the feasible limits of autologous tumor vaccine yield. No evidence of autoimmune disease was observed. Biopsies of intradermal sites of injection with GM-CSF gene-transduced vaccines contained distinctive macrophage, dendritic cell, eosinophil, neutrophil, and T-cell infiltrates similar to those observed in preclinical models of efficacy. Histological analysis of delayed-type hypersensitivity responses in patients vaccinated 1 This work was supported by the NIH GCRC at Johns Hopkins, the Kirby Award of the Cancer Research Institute, the Longrifles Endowment, the Burroughs Wellcome Experimental Therapeutics Award, and the CaPCURE Foundation. Partial funding for this study was provided by Somatix Corporation. Under an agreement between Somatix and the Johns Hopkins University, D. P. is entitled to a share of sales royalty received by the University from Somatix. The terms of this arrangement are being managed by the University in accordance with its conflict of interest policies.

Human b-defensin-1 (hBD-1) is a candidate tumor suppressor gene located on chromosome 8p23. Previously, we showed that cancer-specific loss of hBD-1 was found in 90% of renal clear cell carcinomas and in 82% of prostate cancers. To investigate the possible mechanisms of decreased gene expression and determine the function of hBD-1 protein in urological cancers, we sequenced hBD-1 gene coding regions in prostatic and renal cancer samples. We then analyzed the frequency distribution of promoter polymorphisms and determined the effect of these base changes on transcriptional activity of the hBD-1 promoter. A polymorphism at À688 bases upstream of the ATG start codon affects hBD-1 promoter activity, leading to a rate of reporter gene transcription that is 40% to 50% lower than the wild-type sequence when tested in either DU145 or TSU-Pr1 cell lines. In addition, a polymorphism at À44 bases was shown to enhance transcription up to 2.3 times more than the wild-type sequence in the same cell lines. In addition, three novel hBD-1 promoter mutations were found in renal and prostate cancer clinical samples. An iso-5-aza-2 ¶-deoxycytidine treatment was effective in transcription up-regulation in DU145, suggesting a possible upstream methylation-dependent effect. Synthetic hBD-1 peptide inhibited bladder cancer cell TSU-Pr1 proliferation. Overexpression of the hBD-1 gene in renal cancer cells SW156 resulted in caspase-3-mediated apoptosis. These data support the hypothesis that hBD-1 is a potential tumor suppressor gene for urological cancers. Promoter point mutations may be responsible for cancer-specific loss of hDB-1 expression.