Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0376358 (prostate cancer)
 59,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The past four decades of epidemiological research have yielded valuable information on the risks of populations to environmental exposures such as tobacco, asbestos, and dietary components. Prevention efforts have been focused on large-scale population-based interventions to minimize exposure to such external carcinogens. While some cancers are beginning to show a decline from changing environmental exposures, hormone-related cancers, such as breast and prostate, are becoming more prevalent. The development of these cancers appears to be closely related to endogenous exposures to circulating steroid hormones. Although prevention trials using antihormone agents are proving successful in some instances, the long-term control of these cancers necessitates a clearer understanding of the metabolism and transport of the relevant hormone in vivo. The revolution in molecular biology has provided powerful genetic tools for evaluating mechanisms of cancer causation as well as the potential to better define individual susceptibility. Using tobacco exposure as an example, we and others have demonstrated that polymorphisms in genes controlling aromatic amine metabolism provide at least a partial explanation for ethnic and individual susceptibility to bladder cancer. Similar studies have examined genetic polymorphisms in the metabolism of tobacco smoke and lung cancer risk, red meat and colorectal cancer, and aflatoxin and liver cancer. Our current studies have pursued a similar paradigm of genetic polymorphism and individual cancer susceptibility in prostate and breast carcinogenesis. We are evaluating polymorphisms in the steroid 5 alpha-reductase type II and androgen receptor genes in relation to prostate cancer based on the evidence that intracellular dihydrotestosterone is the critical "carcinogen." We are pursuing genetic polymorphisms affecting estradiol metabolism, including those in the 17 beta-hydroxysteroid dehydrogenase 2 and estrogen receptor genes as they relate to susceptibility to breast cancer. The potential role of a polymorphism in the cytochrome P450c 17 alpha gene in both breast and prostate cancers is also being examined.
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PMID:Genetic susceptibility to cancer from exogenous and endogenous exposures. 902 93

Prostatic steroid 5-alpha-reductase gene (SRD5A2) encodes a critical enzyme involved in the conversion of testosterone to dihydrotestosterone. A germline mis-sense substitution (A49T) leads to a variant SRD5A2 protein, which has a 5-fold higher in vitro V(max)than the wild-type protein (Ross et al, 1998; Makridakis et al, 1999). The A49T variant was recently associated with 2.5 to 3.28-fold increased risk of prostate cancer (PC) in African-American and Hispanic men (Makridakis et al, 1999). Also, Jaffe et al (2000) reported an association between A49T and more aggressive disease among Caucasian patients. Here, we report that the prevalence of the A49T variant in 449 Finnish PC patients was 6.0%, not significantly different from 6.3% observed in 223 patients with benign prostatic hyperplasia or 5.8% in 588 population-based controls (odds ratio for PC 1.04, 95% C.I. 0.62-1.76, P = 0.89). There was no association between A49T and the family history of the patients nor with tumour stage or grade. Our results argue against a prominent role of the A49T variant as a genetic risk factor for prostate cancer development and progression in the Finnish population.
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PMID:A missense substitution A49T in the steroid 5-alpha-reductase gene (SRD5A2) is not associated with prostate cancer in Finland. 1135 45

Androgens are essential for the growth of the prostate gland and have been implicated in the development of prostate cancer. Little is known about the determinants of androgen levels in men, although observed ethnic differences suggest they may have a genetic basis. Several polymorphisms have been identified in the steroid 5 alpha-reductase type II gene (SRD5A2), which encodes an enzyme that catalyzes the conversion of testosterone to its more potent metabolite, dihydrotestosterone. Although some of these polymorphisms have been associated with increased prostate cancer risk, the association with circulating androgen levels remains unclear. The purpose of this study is to investigate the association between the (TA)(n) dinucleotide repeat polymorphism in the 3' untranslated region and the A49T polymorphism (which replaces the normal alanine with threonine at codon 49) in the SRD5A2 gene and serum androgen concentrations in 604 British men. In particular, we wanted to test the hypotheses that the variant alleles are associated with an increased serum concentration of androstanediol glucuronide, a direct metabolite of dihydrotestosterone and a serum marker of 5 alpha-reductase activity. Mean hormone concentrations were evaluated in each genotype, and adjusted for age and other relevant factors. We found no evidence that the SRD5A2 (TA)(n) repeat polymorphism was associated with androgen levels. Men who possessed one or two copies of the variant T allele in the A49T polymorphism had a significantly 24% lower androstanediol glucuronide concentration than men who were homozygous for the wild-type allele (P = 0.0003). Because of the rarity of this variant allele, larger studies are needed to additionally clarify the role of the A49T polymorphism in androgen metabolism.
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PMID:Association between two polymorphisms in the SRD5A2 gene and serum androgen concentrations in British men. 1281 6

Some untranslated sequence (UTR)-localized, short tandem repeats (STRs) exhibit evidence of selection pressure, including STR-coupling preferences, STR conservation, interspecies STR-STR replacements, and STR variants implicated in certain diseases. We wished to determine if STR replacements occurred near disease-related genes, including previously unstudied STRs as well as some STRs already implicated in disease. Among nine strong-candidate prostate cancer (CaP)-predisposing genes, three [steroid 5-alpha-reductase 2 (Srd5A-2), macrophage scavenger receptor-1 (MSR-1), and tumor necrosis factor receptor-21 (Tnfr-21)] exhibited striking STR replacements (P<0.001). The glomerular disease-related gene, CD2AP, exhibited an STR replacement flanked by well-conserved sequences, suggesting an STR-focused process. Another glomerular disease-related gene, rabphilin 3A, exhibited at least two STR replacements at the same UTR position comparing Drosophila melanogaster, Mus musculus, and Homo sapiens. Two genes implicated in blood-clotting disorders, von Willebrand factor (vWA) and fibrinogen alpha (FGA), exhibited multiple-intron STR replacements among mammals, extending STR replacement phenomena to introns. Among primates, a tyrosine hydroxylase (THO1) intron STR, previously implicated in both schizophrenia and drug withdrawal delirium, exhibited frequent replacements. Some STR replacements were early events in gene divergence. When STR sequences of closely related species were available, STR replacement was observed to be nearly as rapid as speciation. STR replacements expand the list of STR sequences that may contribute to genetic activity and to disease processes.
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PMID:Short tandem repeat (STR) replacements in UTRs and introns suggest an important role for certain STRs in gene expression and disease. 1565 86

Human steroid 5 alpha-reductase type II is a prostate-specific, membrane-associated enzyme that catalyzes the conversion of testosterone to dihydrotestosterone, the most potent androgen in the prostate gland. Genetic variants of this enzyme have been associated with both the development and the progression of prostate cancer. Both finasteride and dutasteride are competitive inhibitors of the type II steroid 5 alpha-reductase that have been effectively used for the treatment of benign prostatic hyperplasia. Finasteride has also been successfully utilized for prostate cancer chemoprevention. We here investigate 5 alpha-reductase inhibition assays in vitro to measure the effect of incubation time on the apparent inhibition constant (Ki) for both constitutional and somatic (prostate cancer) enzyme variants. Our systematic pharmacogenetic analysis shows that both finasteride and dutasteride are slow, time-dependent inhibitors of steroid 5 alpha-reductase type II, and that the inhibition kinetics depend on the 5 alpha-reductase genotype. We also show that, overall, dutasteride is a more efficient steroid 5 alpha-reductase inhibitor than finasteride. Based on our data, we are able to map areas of the enzyme that are responsible for this time-dependent inhibition for either (or both) enzyme inhibitor(s). This comprehensive pharmacogenetic analysis of steroid 5 alpha-reductase variants unveiled significant pharmacogenetic variation for both finasteride and dutasteride and thus should be taken into account when designing protocols for treatment and/or chemoprevention of prostatic diseases with either one of these 5 alpha-reductase inhibitors since there is considerable pharmacogenetic variation for both drugs.
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PMID:Pharmacogenetic analysis of human steroid 5 alpha reductase type II: comparison of finasteride and dutasteride. 1595 33

Increased levels of androgen dihydrotestosterone is responsible for the development of prostate cancer in humans. The formation of dihydrotestosterone from testosterone is catalysed by an intracellular enzyme 3-oxo-5-alpha-steroid 4-dehydrogenase 2, which is found to be the most promising target for the treatment of prostate cancer. In this study, the identification of a therapeutic inhibitor of 3-oxo-5-alpha-steroid 4-dehydrogenase 2 using in silico approach has been done to treat prostate cancer. ZINC biogenic compounds (Zbc) database was used for docking and virtual screening against the predicted structure. The MD simulation of the docked complex was done to ensure the ligand interaction with 3-oxo-5-alpha-steroid 4-dehydrogenase 2 for 100 ns. The validation results of the established 3D structure strongly favoured the acceptance reliability of the predicted model. Zbc was screened against 3-oxo-5-alpha-steroid 4-dehydrogenase 2 and ZINC00277963 was selected as the lead with significant docking pose with docking score of -9.961 kcal/mole and having -63.182 kcal/mol binding affinity. The protein-ligand complex system remained stable throughout the MD run and seven stable hydrogen bonds were observed. Our study proposes a lead compound that could be validated by in vitro experimental method(s), suggesting its ability to function as a prospective therapeutic drug against prostate cancer.
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PMID:In silico screening of potential lead compounds against 3-oxo-5-alpha-steroid 4-dehydrogenase 2 for treating prostate cancer. 3160 Oct 57