Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1519176 (PSA)
 5,490 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Approximately one-third of prostate cancer patients present with intermediate risk disease. Interestingly, while this risk group is clinically well defined, it demonstrates the most significant heterogeneity in PSA-based biochemical outcome. Further, the majority of candidate genes associated with prostate cancer progression have been identified using cell lines, xenograft models, and high-risk androgen-independent or metastatic patient samples. We used a global high-resolution array comparative genomic hybridization (CGH) assay to characterize copy number alterations (CNAs) in intermediate risk prostate cancer. Herein, we show this risk group contains a number of alterations previously associated with high-risk disease: (1) deletions at 21q22.2 (TMPRSS2:ERG), 16q22-24 (containing CDH1), 13q14.2 (RB1), 10q23.31 (PTEN), 8p21 (NKX3.1); and, (2) amplification at 8q21.3-24.3 (containing c-MYC). In addition, we identified six novel microdeletions at high frequency: 1q42.12-q42.3 (33.3%), 5q12.3-13.3 (21%), 20q13.32-13.33 (29.2%), 22q11.21 (25%), 22q12.1 (29.2%), and 22q13.31 (33.3%). Further, we show there is little concordance between CNAs from these clinical samples and those found in commonly used prostate cancer cell models. These unexpected findings suggest that the intermediate-risk category is a crucial cohort warranting further study to determine if a unique molecular fingerprint can predict aggressive versus indolent phenotypes.
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PMID:High-resolution array CGH identifies novel regions of genomic alteration in intermediate-risk prostate cancer. 1935 May 49

Despite the use of PSA, Gleason score, and T-category as prognosticators in intermediate-risk prostate cancer, 20-40% of patients will fail local therapy. In order to optimize treatment approaches for intermediate-risk patients, additional genetic prognosticators are needed. Previous reports using array comparative genomic hybridization (aCGH) in radical prostatectomy cohorts suggested a combination of allelic loss of the PTEN gene on 10q and allelic gain of the c-MYC gene on 8q were associated with metastatic disease. We tested whether copy number alterations (CNAs) in PTEN (allelic loss) and c-MYC (allelic gain) were associated with biochemical relapse following modern-era, image-guided radiotherapy (mean dose 76.4 Gy). We used aCGH analyses validated by fluorescence in-situ hybridization (FISH) of DNA was derived from frozen, pre-treatment biopsies in 126 intermediate-risk prostate cancer patients. Patients whose tumors had CNAs in both PTEN and c-MYC had significantly increased genetic instability (percent genome alteration; PGA) compared to tumors with normal PTEN and c-MYC status (p < 0.0001). We demonstrate that c-MYC gain alone, or combined c-MYC gain and PTEN loss, were increasingly prognostic for relapse on multivariable analyses (hazard ratios (HR) of 2.58/p = 0.005 and 3.21/p = 0.0004; respectively). Triaging patients by the use of CNAs within pre-treatment biopsies may allow for better use of systemic therapies to target sub-clinical metastases or locally recurrent disease and improve clinical outcomes.
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PMID:Copy number alterations of c-MYC and PTEN are prognostic factors for relapse after prostate cancer radiotherapy. 2228 94

In prostate biopsies and in prostatectomy specimens, the Gleason score remains the strongest prognosticator of prostate cancer progression, in addition to serum PSA level and DRE findings, in spite of numerous potential biomarkers discovered during the last few decades. Inter- and intratumoural heterogeneity may have limited the employment of tissue biomarkers on prostate biopsies. Nevertheless, the monoclonality of morphologically heterogeneous (Gleason score 7) tumour foci would suggest that genetic biomarkers, arising early in prostate carcinogenesis, may overcome issues related to intratumoural heterogeneity. In spite of the above limitations, a few biomarkers including the proliferation marker Ki-67 and genetic markers such as c-MYC and PTEN have consistently shown their independent prognostic impact both for biochemical recurrence and for clinical outcome parameters such as metastatic disease or prostate-specific mortality. The routine application of biomarkers requiring immunostaining (e.g. Ki-67) has particularly been hindered by the lack of standardized protocols for processing and scoring, while the application of fluorescence in situ hybridization (FISH) technology is considered more labour intensive but better standardized. Future steps to enhance the uptake of prostate tissue biomarkers should be focused on prospective studies, particularly on prostate biopsy specimens, using protocols that are highly standardized for the processing and scoring of the biomarkers. A few recently developed RNA-based test signatures may provide an alternative to FISH or immunohistochemistry-based tests.
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PMID:Prognostic prostate tissue biomarkers of potential clinical use. 2448 90

Prostate cancer (PCa) is the most common non-cutaneous cancer in men. The androgen receptor (AR), a ligand-activated transcription factor, constitutes the main drug target for advanced cases of the disease. However, a variety of other transcription factors and signaling networks have been shown to be altered in patients and to influence AR activity. Amongst these, the oncogenic transcription factor c-Myc has been studied extensively in multiple malignancies and elevated protein levels of c-Myc are commonly observed in PCa. Its impact on AR activity, however, remains elusive. In this study, we assessed the impact of c-Myc overexpression on AR activity and transcriptional output in a PCa cell line model and validated the antagonistic effect of c-MYC on AR-targets in patient samples. We found that c-Myc overexpression partially reprogrammed AR chromatin occupancy and was associated with altered histone marks distribution, most notably H3K4me1 and H3K27me3. We found c-Myc and the AR co-occupy a substantial number of binding sites and these exhibited enhancer-like characteristics. Interestingly, c-Myc overexpression antagonised clinically relevant AR target genes. Therefore, as an example, we validated the antagonistic relationship between c-Myc and two AR target genes, KLK3 (alias PSA, prostate specific antigen), and Glycine N-Methyltransferase (GNMT), in patient samples. Our findings provide unbiased evidence that MYC overexpression deregulates the AR transcriptional program, which is thought to be a driving force in PCa.
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PMID:c-Myc Antagonises the Transcriptional Activity of the Androgen Receptor in Prostate Cancer Affecting Key Gene Networks. 2844 Mar 28