More than 1,000,000 men undergo prostate biopsy each year in the United States, most for “elevated” serum prostate specific antigen (PSA). Given the lack of specificity and unclear mortality benefit of PSA testing, methods to individualize management of elevated PSA are needed. Greater than 50% of PSA-screened prostate cancers harbor fusions between the transmembrane protease, serine 2 (TMPRSS2) and v-ets erythroblastosis virus E26 oncogene homolog (avian) (ERG) genes. Here, we report a clinical-grade, transcription-mediated amplification assay to risk stratify and detect prostate cancer noninvasively in urine. The TMPRSS2:ERG fusion transcript was quantitatively measured in prospectively collected whole urine from 1312 men at multiple centers. Urine TMPRSS2:ERG was associated with indicators of clinically significant cancer at biopsy and prostatectomy, including tumor size, high Gleason score at prostatectomy, and upgrading of Gleason grade at prostatectomy. TMPRSS2:ERG, in combination with urine prostate cancer antigen 3 (PCA3), improved the performance of the multivariate Prostate Cancer Prevention Trial risk calculator in predicting cancer on biopsy. In the biopsy cohorts, men in the highest and lowest of three TMPRSS2:ERG+PCA3 score groups had markedly different rates of cancer, clinically significant cancer by Epstein criteria, and high-grade cancer on biopsy. Our results demonstrate that urine TMPRSS2:ERG, in combination with urine PCA3, enhances the utility of serum PSA for predicting prostate cancer risk and clinically relevant cancer on biopsy.

Background TMPRSS2:ERG (T2:ERG) and prostate cancer antigen 3 (PCA3) are the most advanced urine-based prostate cancer (PCa) early detection biomarkers. Objective Validate logistic regression models, termed Mi-Prostate Score (MiPS), that incorporate serum prostate-specific antigen (PSA; or the multivariate Prostate Cancer Prevention Trial risk calculator version 1.0 [PCPTrc]) and urine T2:ERG and PCA3 scores for predicting PCa and high-grade PCa on biopsy. Design, setting, and participants T2:ERG and PCA3 scores were generated using clinical-grade transcription-mediated amplification assays. Pretrained MiPS models were applied to a validation cohort of whole urine samples prospectively collected after digital rectal examination from 1244 men presenting for biopsy. Outcome measurements and statistical analysis Area under the curve (AUC) was used to compare the performance of serum PSA (or the PCPTrc) alone and MiPS models. Decision curve analysis (DCA) was used to assess clinical benefit. Results and limitations Among informative validation cohort samples (n = 1225 [98%], 80% from patients presenting for initial biopsy), models incorporating T2:ERG had significantly greater AUC than PSA (or PCPTrc) for predicting PCa (PSA: 0.693 vs 0.585; PCPTrc: 0.718 vs 0.639; both p < 0.001) or high-grade (Gleason score >6) PCa on biopsy (PSA: 0.729 vs 0.651, p < 0.001; PCPTrc: 0.754 vs 0.707, p = 0.006). MiPS models incorporating T2:ERG score had significantly greater AUC (all p < 0.001) than models incorporating only PCA3 plus PSA (or PCPTrc or high-grade cancer PCPTrc [PCPThg]). DCA demonstrated net benefit of the MiPS_PCPTrc (or MiPS_PCPThg) model compared with the PCPTrc (or PCPThg) across relevant threshold probabilities. Conclusions Incorporating urine T2:ERG and PCA3 scores improves the performance of serum PSA (or PCPTrc) for predicting PCa and high-grade PCa on biopsy. Patient summary Incorporation of two prostate cancer (PCa)-specific biomarkers (TMPRSS2:ERG and PCA3) measured in the urine improved on serum prostate-specific antigen (or a multivariate risk calculator) for predicting the presence of PCa and high-grade PCa on biopsy. A combined test, Mi-Prostate Score, uses models validated in this study and is clinically available to provide individualized risk estimates.

PCA3 is independent of prostate volume, serum prostate specific antigen level and the number of prior biopsies. The quantitative PCA3 score correlated with the probability of positive biopsy. Logistic regression results suggest that the PCA3 score could be incorporated into a nomogram for improved prediction of biopsy outcome. The results of this study provide further evidence that PCA3 is a useful adjunct to current methods for prostate cancer diagnosis.

human immunodeficiency virus type 1 (HIV-1) Nef interacts with the clathrin-associated AP-1 and AP-3 adaptor complexes, stabilizing their association with endosomal membranes. These findings led us to hypothesize a general impact of this viral protein on the endosomal system. Here, we have shown that Nef specifically disturbs the morphology of the early/recycling compartment, inducing a redistribution of early endosomal markers and a shortening of the tubular recycling endosomal structures. Furthermore, Nef modulates the trafficking of the transferrin receptor (TfR), the prototypical recycling surface protein, indicating that it also disturbs the function of this compartment. Nef reduces the rate of recycling of TfR to the plasma membrane, causing TfR to accumulate in early endosomes and reducing its expression at the cell surface. These effects depend on the leucine-based motif of Nef, which is required for the membrane stabilization of AP-1 and AP-3 complexes. Since we show that this motif is also required for the full infectivity of HIV-1 virions, these results indicate that the positive influence of Nef on viral infectivity may be related to its general effects on early/recycling endosomal compartments.Trafficking of membrane proteins is governed by a regulated machinery that involves the vesicular transport of proteins throughout different intracellular compartments. One major regulatory mechanism is related to the function of the adaptor protein (AP) 1 complexes that assemble on donor membranes of the endocytic pathway to form transport vesicles (for review, see Ref. 1). The sorting of transmembrane proteins into these vesicles requires the recognition by the AP complexes of specific tyrosine-or leucine-based motifs contained within the cytoplasmic domains of cargo proteins (2). Four different types of heterotetrameric AP complexes (AP-1-AP-4) have been identified (3). AP-2 is specifically involved in the formation of clathrincoated vesicles at the plasma membrane, whereas AP-1 and AP-3 mediate the formation of clathrin-coated vesicles at the levels of the trans-Golgi network (TGN) and endosomes. The function of AP-4 is less well documented, but it regulates formation of non-clathrin-coated vesicles at the TGN. The association of the AP-1, AP-3, and AP-4 complexes with TGN and endosomal membranes is regulated by ADP-ribosylation factor 1 (ARF1). The Nef protein of HIV-1 is a 27-kDa protein that associates with the cell membranes through N-terminal myristoylation and is abundantly produced shortly after virus infection (for review, see Refs. 4 and 5). Nef is an essential factor in vivo for efficient viral replication and pathogenesis. In vitro, Nef also facilitates virus replication and enhances the infectivity of virions. Although the positive influence of Nef on viral replication and infectivity may be multifactorial, genetic evidence suggests a relationship between these virological effects and the ability of Nef to modulate the cell surface expression of multiple membrane-associated proteins. In additio...

New markers for prostate cancer can be incorporated into the Prostate Cancer Prevention Trial risk calculator by a novel approach. Incorporation of prostate cancer gene 3 improved the diagnostic accuracy of the Prostate Cancer Prevention Trial risk calculator.