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The TMPRSS2-ETS fusion prostate cancers comprise 50-70% of the prostate-specific antigen (PSA)-screened hospital-based prostate cancers examined to date, making it perhaps the most common genetic rearrangement in human cancer. The most common variant involves androgen-regulated TMPRSS2 and ERG, both located on chromosome 21. Emerging data from our group and others suggests that TMPRSS2-ERG fusion prostate cancer is associated with higher tumour stage and prostate cancer-specific death. The goal of this study was to determine if this common somatic alteration is associated with a morphological phenotype. We assessed 253 prostate cancer cases for TMPRSS2-ERG fusion status using an ERG break-apart FISH assay. Blinded to gene fusion status, two reviewers assessed each tumour for presence or absence of eight morphological features. Statistical analysis was performed to look for significant associations between morphological features and TMPRSS2-ERG fusion status. Five morphological features were associated with TMPRSS2-ERG fusion prostate cancer: blue-tinged mucin, cribriform growth pattern, macronucleoli, intraductal tumour spread, and signet-ring cell features, all with p-values < 0.05. Only 24% ( n = 30/125) of tumours without any of these features displayed the TMPRSS2-ERG fusion. By comparison, 55% ( n = 38/69) of cases with one feature (RR = 3.88), 86% ( n = 38/44) of cases with two features (RR = 20.06), and 93% ( n = 14/15) of cases with three or more features (RR = 44.33) were fusion positive ( p < 0.001). To our knowledge, this is the first study that demonstrates a significant link between a molecular alteration in prostate cancer and distinct phenotypic features. The strength of these findings is similar to microsatellite unstable colon cancer and breast cancer involving BRCA1 and BRCA2 mutations. The biological effect of TMPRSS2-ERG overexpression may drive pathways that favour these common morphological features that pathologists observe daily. These features may also be helpful in diagnosing TMPRSS2-ERG fusion prostate cancer, which may have both prognostic and therapeutic implications. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The precipitating event(s) that triggers Wegener's granulomatosis (WG) is unknown. Cytokines, costimulatory molecules, and counterregulatory molecules control the quality and intensity of immune responses. Thus, they are relevant candidates for genetic studies of immune dysregulation in WG, the pathogenesis of which may be facilitated by multiple acquired and/or inherited factors. This study was undertaken to investigate possible genetic associations of various proinflammatory cytokines and CTLA-4, a receptor for T cell inhibition, with WG. METHODS: Using polymerase chain reaction-based DNA genotyping, we investigated the polymorphisms located in the genes encoding a variety of proinflammatory cytokines and CTLA-4 in 117 American patients with WG and 123 ethnically matched healthy controls. RESULTS: Compared with controls, patients with WG had a significantly lower frequency of homozygosity for the shortest allele (designated allele 86) of the Ctla4 microsatellite polymorphism (AT)n located in the 3'-untranslated region (3'-UTR) of exon 3 (47.0% versus 69.9%; P = 0.0005). Significant differences between patients and controls in the allelic and genotypic frequencies of polymorphisms in the other cytokine and cytokine receptor genes studied (tumor necrosis factor alpha [TNFalpha], TNF receptor I [TNFRI], TNFRII, interleukin-1beta [IL-1beta], IL-6) were not found. CONCLUSION: The Ctla4 (AT)n 86 allele has been previously demonstrated to be crucial for maintenance of normal levels of CTLA-4 expression and balance between T cell activation and inhibition. Our results in American patients confirm findings from a Scandinavian cohort in which a positive association between WG and longer alleles of (AT)n in the Ctla4 3'-UTR was demonstrated. Diminished frequencies of the most effective allele for CTLA-4 expression may represent a WG-related susceptibility mutation that accounts, in part, for increased T cell activation and clonal expansion in WG. Blockade of T cell costimulation using CTLA-4Ig might be a useful therapeutic intervention, providing an alternative or complementary approach to conventional treatment with immunosuppressive agents. [ABSTRACT FROM AUTHOR]