CYP17A1

Gene Summary

Gene:CYP17A1; cytochrome P450 family 17 subfamily A member 1
Aliases: CPT7, CYP17, S17AH, P450C17
Location:10q24.32
Summary:This gene encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. This protein localizes to the endoplasmic reticulum. It has both 17alpha-hydroxylase and 17,20-lyase activities and is a key enzyme in the steroidogenic pathway that produces progestins, mineralocorticoids, glucocorticoids, androgens, and estrogens. Mutations in this gene are associated with isolated steroid-17 alpha-hydroxylase deficiency, 17-alpha-hydroxylase/17,20-lyase deficiency, pseudohermaphroditism, and adrenal hyperplasia. [provided by RefSeq, Jul 2008]
Databases:VEGA, OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:steroid 17-alpha-hydroxylase/17,20 lyase
Source:NCBIAccessed: 14 March, 2017

Ontology:

What does this gene/protein do?
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Pathways:What pathways are this gene/protein implicaed in?
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Cancer Overview

Research Indicators

Publications Per Year (1992-2017)
Graph generated 14 March 2017 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

  • Washington
  • Androgens
  • Catechol O-Methyltransferase
  • Polycystic Ovary Syndrome
  • Testosterone
  • Alleles
  • CYP17A1
  • Chromosome 10
  • Case-Control Studies
  • Mutation
  • Risk Factors
  • 3-Oxo-5-alpha-Steroid 4-Dehydrogenase
  • Signal Transduction
  • Estrogens
  • Adolescents
  • Cholesterol Side-Chain Cleavage Enzyme
  • Uterine Cancer
  • Promoter Regions
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  • Cytochrome P-450 Enzyme System
  • Prostate Cancer
  • Weight Loss
  • Postmenopause
  • Restriction Fragment Length Polymorphism
  • Polymorphism
  • Aromatase
  • Genetic Predisposition
  • Cytochrome P-450 CYP1A1
  • Taiwan
  • European Continental Ancestry Group
  • Messenger RNA
  • Sweden
  • Steroid 21-Hydroxylase
  • Androgen Receptors
  • Biomarkers, Tumor
  • Single Nucleotide Polymorphism
  • Polymerase Chain Reaction
  • Breast Cancer
  • Cancer Gene Expression Regulation
  • Odds Ratio
  • Genotype
Tag cloud generated 14 March, 2017 using data from PubMed, MeSH and CancerIndex

Specific Cancers (3)

Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.

Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).

Latest Publications: CYP17A1 (cancer-related)

Tüzüner MB, Öztürk T, Eronat AP, et al.
Evaluation of Local CYP17A1 and CYP19A1 Expression Levels as Prognostic Factors in Postmenopausal Invasive Ductal Breast Cancer Cases.
Biochem Genet. 2016; 54(6):784-802 [PubMed] Related Publications
There is growing attention focused on local estrogen production in the breast tissue and its possible role in breast cancer initiation and progression. Understanding the underlying mechanisms for estrogen synthesis and the microenvironment consisting of tumor and its surrounding adipose tissue might open new avenues in breast cancer prevention, prognosis and treatment. In order to obtain insight, we compared peritumoral and tumor tissue expressions of CYP17A1 and CYP19A1 genes, which play an important role in estrogen biosynthesis. The paired tissue samples of 20 postmenopausal ER(+)/PR(+) patients diagnosed with invasive ductal breast cancer were studied. In addition, 12 breast tissue samples obtained from premenopausal women without a history of breast cancer were also investigated as representative of normal conditions. Peritumoral adipose tissues expressed CYP19A1 approximately threefold higher than tumor itself (p = 0.001). A nonsignificant trend toward low expression of CYP17A1 was observed in peritumoral compared to tumor tissue (p = 0.687). Clinicopathological parameters and patient characteristics which are accepted as risk factors for breast cancer were also associated with individual and combined expressions of CYP17A1 and CYP19A1. This study offers that evaluation of CYP17A1 and CYP19A1 local expression levels might be useful for deciding on personalized treatment approaches and more accurate diagnosis, when evaluated together with several clinicopathological and disease risk factors. Considering the key role of these CYPs in estrogen synthesis, determining their expression levels may be useful as a postdiagnostic marker and for choosing the right treatment method in addition to the conventional approach.

Hussain S, Bano R, Tahir Khan M, Haroon Khan M
Association of the CYP17-34T/C Polymorphism with Pancreatic Cancer Risk.
Asian Pac J Cancer Prev. 2016; 17(S3):71-5 [PubMed] Related Publications
Pancreatic cancer is a leading cause of fatality worldwide. Several population studies have been conducted on genetic diagnosis of pancreatic cancer but the results from epidemiologic studies are very limited. CYP17A gene has a role in disease formation but its influence on pancreatic cancer is unclear. A polymorphism in the 5'UTR promoter region of CYP17A1-34T/C (A1/A2) has been associated with multiple cancers. The aim of the current study was to assess associations of this polymorphism and socio-demographic risk factors with pancreatic cancer. A total of 255 and 320 controls were enrolled in the study, and were genetically analyzed through PCR-RFLP. Statistical analysis was conducted with observed genotype frequencies and odds ratios (ORs) and 95% CIs were estimated using unconditional logistic regression. The impact of socio-demographic factors was accessed through Kaplen-Meir analysis. According to our results, the A2/A2 genotype was significantly associated with pancreatic cancer (OR=2.1, 95%CI = 1.3-3.5). Gender female (OR=2.6, 95%CI=1.8-3.7), age group 80s/80+ years (OR=2.2, 95% CI=1.2-4), smoking both former (OR=4.6, 95% CIs=2.5-8.8) and current (OR=3.6, 95% CI=2-6.7), and family history (OR=7.1; 95%CI = 4.6-11.4) were also found associated with increased risk. Current study suggests that along with established risk factors for pancreatic cancer CYP17A1-34T/C may play a role. However, on the basis of small sample size the argument cannot be fully endorsed and larger scale studies are recommended.

Farzaneh F, Noghabaei G, Barouti E, et al.
Analysis of CYP17, CYP19 and CYP1A1 Gene Polymorphisms in Iranian Women with Breast Cancer.
Asian Pac J Cancer Prev. 2016; 17(S3):23-6 [PubMed] Related Publications
Breast cancer (BC) is the most common cancer and the second cause of mortality in women all around the world. It is caused by several factors including genetic determinants, so that both genetic susceptibility factors and environmental factors are involved in the etiology. Significance of genes functioning in steroid hormone synthesis and metabolism are well established in breast cancer susceptibility. In this study, 134 women with BC and 135 normal controls were analyzed for their genotypes for the polymorphisms, rs743572, rs10046 and rs4646903, resided in CYP17, CYP19 and CYP1A1 genes, respectively. Significant differences in distributions of allele and genotype frequencies were found for the rs10046 polymorphism in CYP19 (p-value=0.01, OR (CI 95%) =1.59 (1.1-2.3), p-value=0.04, OR (CI 95%) =1.7 (1.1-2.5) respectively). For rs743,572 and rs 4646903 polymorphisms, no significant associations were observed. A significant association was observed between the rs10046 polymorphism of the CYP19gene and breast cancer in Iranian patients. Due to inconsistent previous results, more studies in different populations with larger sample sizes are indicated.

Brureau L, Moningo D, Emeville E, et al.
Polymorphisms of Estrogen Metabolism-Related Genes and Prostate Cancer Risk in Two Populations of African Ancestry.
PLoS One. 2016; 11(4):e0153609 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Estrogens are thought to play a critical role in prostate carcinogenesis. It has been suggested that polymorphisms of genes encoding enzymes involved in estrogen metabolism are risk factors for prostate cancer. However, few studies have been performed on populations of African ancestry, which are known to have a high risk of prostate cancer.
OBJECTIVE: We investigated whether functional polymorphisms of CYP17, CYP19, CYP1B1, COMT and UGT1A1 affected the risk of prostate cancer in two different populations of African ancestry.
METHODS: In Guadeloupe (French West Indies), we compared 498 prostate cancer patients and 565 control subjects. In Kinshasa (Democratic Republic of Congo), 162 prostate cancer patients were compared with 144 controls. Gene polymorphisms were determined by the SNaPshot technique or short tandem repeat PCR analysis. Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI).
RESULTS: The AA genotype and the A allele of rs4680 (COMT) appeared to be inversely associated with the risk of prostate cancer in adjusted models for both Afro-Caribbean and native African men. For the A allele, a significant inverse association was observed among cases with low-grade Gleason scores and localized clinical stage, in both populations.
CONCLUSIONS: These preliminary results support the hypothesis that polymorphisms of genes encoding enzymes involved in estrogen metabolism may modulate the risk of prostate cancer in populations of African ancestry.

Song J, Tao ZH, Liu XY, et al.
Relationship between CYP17 gene polymorphisms and risk of prostate cancer.
Genet Mol Res. 2016; 15(1):15017866 [PubMed] Related Publications
Cytochrome P450 17a-hydroxylase (CYP17) plays a critical role in androgen biosynthesis. Polymorphisms of the CYP17 promoter have been proposed as risk factors for prostate cancer; however, some studies have produced inconclusive or controversial results. We investigated the relationship between polymorphisms of the CYP17 gene and the risk of prostate cancer. A total of 176 patients with prostate cancer were enrolled in the study, and 168 healthy individuals acted as the control group. The participants were divided into those <71 years old and those ≥71 years old. Restriction fragment length polymorphism-polymerase chain reaction was used to confirm the genotype of CYP17 in the samples. The prostate-specific antigen (PSA) concentrations were also measured in all subjects. When T/C and C/C were compared with T/T, the ORs were 0.478 (P = 0.489) and 0.814 (P = 0.367), respectively. There was no significant difference in PSA concentration among the three genotypes in the <71 group, whereas there were statistically significant differences in the ≥71 group (P = 0.003 and 0.012, respectively). There was no significant difference in free PSA and total PSA levels between the three groups and the control group. The T/C and C/C genotypes were not associated with the risk of prostate cancer, and there were no significant differences between them. In the ≥71 group, the T/C and C/C genotypes were closely associated with prostate cancer, which suggests that the CYP17 gene might be a risk factor for prostate cancer in males of advanced age.

Cadagan D, Khan R, Amer S
Thecal cell sensitivity to luteinizing hormone and insulin in polycystic ovarian syndrome.
Reprod Biol. 2016; 16(1):53-60 [PubMed] Related Publications
This study examined whether a defect of steroid synthesis in ovarian theca cells may lead to the development of PCOS, through contributions to excess androgen secretion. Polycystic ovarian syndrome (PCOS) is one of the leading causes of infertility worldwide affecting around 1 in 10 of women of a reproductive age. One of the fundamental abnormalities in this syndrome is the presence of hormonal irregularities, including hyperandrogenemia, hyperinsulinemia and hypersecretion of luteinizing hormone (LH). Studies suggest that insulin treatment increases progesterone and androstenedione secretion in PCOS theca cells when compared to insulin treated normal theca cells. Furthermore the augmented effects of LH and insulin have been seen to increase ovarian androgen synthesis in non-PCOS theca cultures whilst also increasing the expression of steroidogenic enzymes specific to the PI3-K pathway. Our examination of primary thecal cultures showed an increase in both the expression of the steroidogenic enzyme CYP17 and androgen secretion in PCOS theca cells under basal conditions, when compared to non-PCOS cells. This was increased significantly under treatments of LH and insulin combined. Our results support the previous reported hypothesis that a dysfunction may exist within the PI3-K pathway. Specifically, that sensitivity exists to physiological symptoms including hyperinsulinemia and hyper secretion of LH found in PCOS through co-stimulation. The impact of these findings may allow the development of a therapeutic target in PCOS.

Fujisawa Y, Sakaguchi K, Ono H, et al.
Combined steroidogenic characters of fetal adrenal and Leydig cells in childhood adrenocortical carcinoma.
J Steroid Biochem Mol Biol. 2016; 159:86-93 [PubMed] Related Publications
Although childhood adrenocortical carcinomas (c-ACCs) with a TP53 mutation are known to produce androgens, detailed steroidogenic characters have not been clarified. Here, we examined steroid metabolite profiles and expression patterns of steroidogenic genes in a c-ACC removed from the left adrenal position of a 2-year-old Brazilian boy with precocious puberty, using an atrophic left adrenal gland removed at the time of tumorectomy as a control. The c-ACC produced not only abundant dehydroepiandrosterone-sulfate but also a large amount of testosterone via the Δ5 pathway with Δ5-androstenediol rather than Δ4-androstenedione as the primary intermediate metabolite. Furthermore, the c-ACC was associated with elevated expressions of CYP11A1, CYP17A1, POR, HSD17B3, and SULT2A1, a low but similar expression of CYB5A, and reduced expressions of AKR1C3 (HSD17B5) and HSD3B2. Notably, a Leydig cell marker INSL3 was expressed at a low but detectable level in the c-ACC. Furthermore, molecular studies revealed a maternally inherited heterozygous germline TP53 mutation, and several post-zygotic genetic aberrations in the c-ACC including loss of paternally derived chromosome 17 with a wildtype TP53 and loss of maternally inherited chromosome 11 and resultant marked hyperexpression of paternally expressed growth promoting gene IGF2 and drastic hypoexpression of maternally expressed growth suppressing gene CDKN1C. These results imply the presence of combined steroidogenic properties of fetal adrenal and Leydig cells in this patient's c-ACC with a germline TP53 mutation and several postzygotic carcinogenic events.

Sakai M, Martinez-Arguelles DB, Aprikian AG, et al.
De novo steroid biosynthesis in human prostate cell lines and biopsies.
Prostate. 2016; 76(6):575-87 [PubMed] Related Publications
BACKGROUND: Intratumoral androgen formation may be a factor in the development of prostate cancer (PCa), particularly castration-resistant prostate cancer (CRPC). To evaluate the ability of the human prostate to synthesize de novo steroids, we examined the expression of key enzymes and proteins involved in steroid biosynthesis and metabolism.
METHODS: Using TissueScan™ Cancer qPCR Arrays and quantitative RT-PCR, we performed comparative gene expression analyses between various prostate cell lines and biopsies, including normal, hyperplastic, cancerous, and androgen-deprived prostate cells lines, as well as normal, benign prostate hyperplasia (BPH), PCa, and CRPC human specimens. These studies were complemented with steroid biosynthesis studies in normal and BPH cells.
RESULTS: Normal human prostate WPMY-1 and WPE1-NA22, benign prostate hyperplasia BPH-1, and cancer PC-3, LNCaP, and VCaP cell lines, as well as normal, BPH, PCa, and CRPC specimens, were used. Although all cell lines express mRNA encoding for hydroxymethylglutaryl-CoA reductase (HMGCR), the mitochondrial translocator protein TSPO and cholesterol side chain cleavage enzyme CYP11A1 were only observed in WPMY-1, BPH-1, and LNCaP cells. HSD3B1, HSD3B2, and CYP17A1 are involved in androgen formation and were not found in most cell lines. WPE1-NA22 and BPH-1 cells were unable to synthesize de novo steroids from mevalonate. Moreover, androgen-deprived cells did not have alterations in the expression of enzymes that could lead to de novo steroid formation. All prostate specimens expressed TSPO and CYP11A1. HSD3B1/2, CYP17A1, HSD17B5, and CYP19A1 mRNA expression was distinct to the profile observed in cells lines. The majority of BPH (90.9%) and PCa (83.1%) specimens contained CYP17A1, compared to control (normal) specimens (46.7%). BPH (82%), PCa (59%), normal (40%), and CRPC (34%) specimens expressed the four key enzymes that metabolize cholesterol to androgens.
CONCLUSION: These studies question the use of prostate cell lines to study steroid biosynthesis and demonstrate that human prostate samples contain transcripts encoding for key steroidogenic enzymes and proteins indicating that they have the potential to synthesize de novo steroids. We propose CYP17A1 as a candidate enzyme that can be used for patient stratification and treatment in BPH and PCa.

Lintermans A, Van Asten K, Jongen L, et al.
Genetic variant in the osteoprotegerin gene is associated with aromatase inhibitor-related musculoskeletal toxicity in breast cancer patients.
Eur J Cancer. 2016; 56:31-6 [PubMed] Related Publications
BACKGROUND: Aromatase inhibitor (AI) therapy is associated with musculoskeletal (MS) toxicity, which adversely affects quality of life and therapy adherence. Our objective was to evaluate whether genetic variants may predict endocrine therapy-related MS pain and hot flashes in a prospective observational cohort study.
PATIENTS & METHODS: 254 early breast cancer patients starting AI (n = 159) or tamoxifen therapy (n = 95) were included in this genetic biomarker study. MS and vasomotor symptoms were assessed at baseline and after 3, 6 and 12 months of therapy. AI-induced MS pain was defined as an increase in arthralgia or myalgia relative to baseline. Single nucleotide polymorphisms (SNP) in candidate genes involved in oestrogen signalling or previously associated with AI-related MS pain or oestrogen levels were selected.
RESULTS: Overall, 13 SNPs in CYP19, CYP17, osteoprotegerin (OPG) and oestrogen receptor 1 exhibited an allele frequency >0.05 and were included in the analysis. Patients carrying the G allele of rs2073618 in OPG experienced significantly more AI-induced MS toxicity compared to the wildtype allele, after correction for multiple testing (P = 0.046). Furthermore, this SNP was associated with severity of pain (P = 0.018). No association was found with regard to the other SNPs, both in AI and tamoxifen-treated patients. Neither could an association with vasomotor symptoms be demonstrated.
CONCLUSION: The SNP rs2073618 in OPG is associated with an increased risk of MS symptoms and pain with AI therapy, which has not been reported previously. Validation of this finding in larger cohorts and further functional studies are required.

Rai R, Kim JJ, Misra S, et al.
A Multiple Interaction Analysis Reveals ADRB3 as a Potential Candidate for Gallbladder Cancer Predisposition via a Complex Interaction with Other Candidate Gene Variations.
Int J Mol Sci. 2015; 16(12):28038-49 [PubMed] Free Access to Full Article Related Publications
Gallbladder cancer is the most common and a highly aggressive biliary tract malignancy with a dismal outcome. The pathogenesis of the disease is multifactorial, comprising the combined effect of multiple genetic variations of mild consequence along with numerous dietary and environmental risk factors. Previously, we demonstrated the association of several candidate gene variations with GBC risk. In this study, we aimed to identify the combination of gene variants and their possible interactions contributing towards genetic susceptibility of GBC. Here, we performed Multifactor-Dimensionality Reduction (MDR) and Classification and Regression Tree Analysis (CRT) to investigate the gene-gene interactions and the combined effect of 14 SNPs in nine genes (DR4 (rs20576, rs6557634); FAS (rs2234767); FASL (rs763110); DCC (rs2229080, rs4078288, rs7504990, rs714); PSCA (rs2294008, rs2978974); ADRA2A (rs1801253); ADRB1 (rs1800544); ADRB3 (rs4994); CYP17 (rs2486758)) involved in various signaling pathways. Genotyping was accomplished by PCR-RFLP or Taqman allelic discrimination assays. SPSS software version 16.0 and MDR software version 2.0 were used for all the statistical analysis. Single locus investigation demonstrated significant association of DR4 (rs20576, rs6557634), DCC (rs714, rs2229080, rs4078288) and ADRB3 (rs4994) polymorphisms with GBC risk. MDR analysis revealed ADRB3 (rs4994) to be crucial candidate in GBC susceptibility that may act either alone (p < 0.0001, CVC = 10/10) or in combination with DCC (rs714 and rs2229080, p < 0.0001, CVC = 9/10). Our CRT results are in agreement with the above findings. Further, in-silico results of studied SNPs advocated their role in splicing, transcriptional and/or protein coding regulation. Overall, our result suggested complex interactions amongst the studied SNPs and ADRB3 rs4994 as candidate influencing GBC susceptibility.

Udhane SS, Flück CE
Regulation of human (adrenal) androgen biosynthesis-New insights from novel throughput technology studies.
Biochem Pharmacol. 2016; 102:20-33 [PubMed] Related Publications
Androgens are precursors for sex steroids and are predominantly produced in the human gonads and the adrenal cortex. They are important for intrauterine and postnatal sexual development and human reproduction. Although human androgen biosynthesis has been extensively studied in the past, exact mechanisms underlying the regulation of androgen production in health and disease remain vague. Here, the knowledge on human androgen biosynthesis and regulation is reviewed with a special focus on human adrenal androgen production and the hyperandrogenic disorder of polycystic ovary syndrome (PCOS). Since human androgen regulation is highly specific without a good animal model, most studies are performed on patients harboring inborn errors of androgen biosynthesis, on human biomaterials and human (tumor) cell models. In the past, most studies used a candidate gene approach while newer studies use high throughput technologies to identify novel regulators of androgen biosynthesis. Using genome wide association studies on cohorts of patients, novel PCOS candidate genes have been recently described. Variant 2 of the DENND1A gene was found overexpressed in PCOS theca cells and confirmed to enhance androgen production. Transcriptome profiling of dissected adrenal zones established a role for BMP4 in androgen synthesis. Similarly, transcriptome analysis of human adrenal NCI-H295 cells identified novel regulators of androgen production. Kinase p38α (MAPK14) was found to phosphorylate CYP17 for enhanced 17,20 lyase activity and RARB and ANGPTL1 were detected in novel networks regulating androgens. The discovery of novel players for androgen biosynthesis is of clinical significance as it provides targets for diagnostic and therapeutic use.

Ek WE, Lagergren K, Cook M, et al.
Polymorphisms in genes in the androgen pathway and risk of Barrett's esophagus and esophageal adenocarcinoma.
Int J Cancer. 2016; 138(5):1146-52 [PubMed] Free Access to Full Article Related Publications
The strong male predominance in Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) remains inadequately explained, but sex hormones might be involved. We hypothesized that single nucleotide polymorphisms (SNPs) in the androgen pathway influence risk of developing BE and EAC. This genetic-epidemiological analysis included 14 studies from Australia, Europe and North America. Polymorphisms in 16 genes coding for the androgen pathway were analyzed using a gene-based approach: versatile gene-based test association study. This method evaluates associations between a trait and all SNPs within a specific gene rather than each SNP marker individually as in a conventional GWAS. The data were stratified for sex, body-mass index, waist-to-hip ratio, tobacco smoking and gastroesophageal reflux status. Included were data from 1,508 EAC patients, 2,383 BE patients and 2,170 control participants. SNPs within the gene CYP17A1 were associated with risk of BE in the sexes combined (p = 0.002) and in males (p = 0.003), but not in females separately (p = 0.3). This association was found in tobacco smokers (p = 0.003) and in BE patients without reflux (p = 0.004), but not in nonsmokers (p = 0.2) or those with reflux (p = 0.036). SNPs within JMJD1C were associated with risk of EAC in females (p = 0.001). However, none of these associations replicated in a subsequent sample. Fourteen other genes studied did not reach statistically significant levels of association with BE, EAC or the combination of BE and EAC, after correcting for the number of genes included in the analysis. In conclusion, genetic variants in the androgen-related genes CYP17A1 and JMJD1C might be associated with risk of BE and EAC, respectively, but replication data with larger sample sizes are needed.

Karakus N, Kara N, Ulusoy AN, et al.
Evaluation of CYP17A1 and LEP Gene Polymorphisms in Breast Cancer.
Oncol Res Treat. 2015; 38(9):418-22 [PubMed] Related Publications
BACKGROUND: Polymorphisms of estrogen synthesis- and adiposity-related genes can contribute to the development of breast cancer. The purpose of the current study was to analyze the association between CYP17A1 T27C (rs743572) and LEP -2548G>A (rs7799039) gene polymorphisms and breast cancer.
MATERIAL AND METHODS: 199 breast cancer patients and 197 healthy controls were included in the study. The CYP17A1 and LEP gene polymorphisms were determined using polymerase chain reaction-based restriction fragment length polymorphism analysis.
RESULTS: No statistically significant association was found between these polymorphisms and breast cancer risk among a Turkish population. However, stratified analysis of these polymorphisms in relation to different clinicopathological characteristics of breast cancer revealed an association between breast cancer diagnosis and the CYP17A1 T27C polymorphism (p = 0.024).
CONCLUSION: Our study suggests no strong association between the CYP17A1 T27C and LEP -2548G>A polymorphisms and the incidence of breast cancer in Turkish women. The potential association between CYP17A1 T27C and the type of breast cancer deserves further consideration.

Dwivedi S, Agrawal S, Singh S, et al.
Association of Cytochrome-17 (MspA1) Gene Polymorphism with Risk of Gall Bladder Stones and Cancer in North India.
Asian Pac J Cancer Prev. 2015; 16(13):5557-63 [PubMed] Related Publications
BACKGROUND: Cholelithiasis is associated in 54%-98% of patients with carcinoma of the gallbladder, and a high incidence among females suggests a role of female hormones in the etiology of the disease. Cytochrome P450C17α (CYP-17) is a key enzyme involved in estrogen metabolism and polymorphisms in CYP-17 are associated with altered serum levels of estrogens. Thus, we investigated whether the CYP-17 MspA1 gene polymorphism might impact on risk of gall bladder cancers or gallstones, as well as to determine if this gene polymorphism might be linked with estrogen serum levels and lipid profile among the North Indian gall bladder cancer or gallstone patients.
MATERIALS AND METHODS: CYP-17 gene polymorphisms (MspA1) were genotyped with PCR-RFLP in cancer patients (n=96), stone patients (n=102), cancer+stone patients (n=52) and age/sex matched control subjects (n=256). Lipid profile was estimated using a commercial kit and serum estrogen was measured using ELISA.
RESULTS: The majority of the patients in all groups were females. The lipid profile and estrogen level were significantly higher among the study as compared to control groups. The frequency of mutant allele A2 of CYP17 MspA1 gene polymorphism was higher among cancer (OR=5.13, 95% CI+3.10-8.51, p=0.0001), stone (OR=5.69, 95%CI=3.46-9.37, p=0.0001) and cancer+stone (OR=3.54, 95%CI=1.90-6.60, p=0.0001) when compared with the control group. However there was no significant association between genotypes of CYP17 MspA1 gene polymorphism and circulating serum level of estrogen and lipid profile.
CONCLUSIONS: A higher frequency of mutant genotype A1A2 as well as mutant allele A2 of CYP-17 gene polymorphism is significantly associated with risk of gallbladder cancer and stones. Elevated levels of estrogen and an altered lipid profile can be used as predictors ofgall bladder stones and cancer in post menopausal females in India.

Ersekerci E, Sofikerim M, Taheri S, et al.
Genetic polymorphism in sex hormone metabolism and prostate cancer risk.
Genet Mol Res. 2015; 14(3):7326-34 [PubMed] Related Publications
We compared single-nucleotide polymorphisms for point mutations in cytochrome P450 genes, including cytochrome P450c17α (CYP17), cytochrome P450 aromatase (CYP19), steroid-5-a-reductase (SRD5A2), and prostate-specific antigen (PSA) involved in androgen and estrogen production. Between January 2008 and January 2010, 90 patients were enrolled in the study. Of these patients, 28 were diagnosed with benign prostatic hyperplasia and 32 with prostate cancer, while 30 subjects were included as a control group. CYP19 1531 C>T, SRD5A2 gene V89L, CYP17 gene -34 T/C, PSA-158 (G/A) regions were evaluated for the association between polymorphisms and benign prostatic hyperplasia and prostate cancer in study population. Age, body mass index, peak urinary flow rate (Q max), voided urine volume, post-void residual urine volume, total PSA, free PSA, free/total PSA ratio, prostate weights measured by transrectal ultrasonography, erectile dysfunction score, and international prostate symptom score were compared between groups. No statistically significant difference in CYP19 1531 C>T, SRD5A2 V89L, and CYP17 -34T/C was observed in both groups when compared to the control group. The homozygote variant of PSA- 158 (G/A) was significantly lower for prostate cancer. Age, total PSA, free PSA, free/total PSA ratio, prostate weight, and Q max were evaluated using multi-variant analysis. Only Q max was significant for the homozygote variant. The probability of being homozygous was 5.8- fold higher in subjects with Q max >14 mL/s. In the Turkish population, the homozygote variant of PSA-158 (G/A) was significantly lower for prostate cancer.

Rodríguez-Sanz M, García-Giralt N, Prieto-Alhambra D, et al.
CYP11A1 expression in bone is associated with aromatase inhibitor-related bone loss.
J Mol Endocrinol. 2015; 55(1):69-79 [PubMed] Related Publications
Aromatase inhibitors (AIs) used as adjuvant therapy in postmenopausal women with hormone receptor-positive breast cancer cause diverse musculoskeletal side effects that include bone loss and its associated fracture. About half of the 391 patients treated with AIs in the Barcelona-Aromatase induced bone loss in early breast cancer cohort suffered a significant bone loss at lumbar spine (LS) and/or femoral neck (FN) after 2 years on AI-treatment. In contrast, up to one-third (19.6% LS, 38.6% FN) showed no decline or even increased bone density. The present study aimed to determine the genetic basis for this variability. SNPs in candidate genes involved in vitamin D and estrogen hormone-response pathways (CYP11A1, CYP17A1, HSD3B2, HSD17B3, CYP19A1, CYP2C19, CYP2C9, ESR1, DHCR7, GC, CYP2R1, CYP27B1, VDR and CYP24A1) were genotyped for association analysis with AI-related bone loss (AIBL). After multiple testing correction, 3 tag-SNPs (rs4077581, s11632698 and rs900798) located in the CYP11A1 gene were significantly associated (P<0.005) with FN AIBL at 2 years of treatment. Next, CYP11A1 expression in human fresh bone tissue and primary osteoblasts was demonstrated by RT-PCR. Both common isoforms of human cholesterol side-chain cleavage enzyme (encoded by CYP11A1 gene) were detected in osteoblasts by western blot. In conclusion, the genetic association of CYP11A1 gene with AIBL and its expression in bone tissue reveals a potential local function of this enzyme in bone metabolism regulation, offering a new vision of the steroidogenic ability of this tissue and new understanding of AI-induced bone loss.

Techatraisak K, Chayachinda C, Wongwananuruk T, et al.
No association between CYP17 -34T/C polymorphism and insulin resistance in Thai polycystic ovary syndrome.
J Obstet Gynaecol Res. 2015; 41(9):1412-7 [PubMed] Related Publications
AIM: To investigate the association of CYP 17 -34T/C polymorphism with insulin resistance (IR) in Thai polycystic ovary syndrome (PCOS).
METHODS: A cross-sectional study was performed on 210 Thai women diagnosed with PCOS. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to analyze CYP17 polymorphism at -34T/C. Student's t-test was used to compare the mean of normally distributed variables between A1/A1 and A2/X. Chi-squared or Fisher's exact tests and OR were used to analyze the association at P < 0.05.
RESULTS: Out of 210 cases, PCR-RFLP was successful in 199. Mean patient age was 24.4 ± 4.7 years, with body mass index 25.2 ± 6.3 kg/m(2) . There were 65 and 134 women in the A1/A1 genotype group and A2/X genotype group, respectively. The A2/X genotype group was statistically significantly younger and had a strong trend toward overweight/obesity compared with the A1/A1 genotype group. The prevalence of IR according to different methods varied from 15.4% to 70.8% and was not different between the two groups. On subgroup analysis, in the overweight/obese PCOS group, the A2/X genotype was not associated with any indices of IR.
CONCLUSION: No significant association between CYP17-34T/C polymorphism and IR was found in Thai PCOS women, although the A2/X genotype group was statistically significantly younger than the A1/A1 genotype group.

Penning TM
Mechanisms of drug resistance that target the androgen axis in castration resistant prostate cancer (CRPC).
J Steroid Biochem Mol Biol. 2015; 153:105-13 [PubMed] Free Access to Full Article Related Publications
Castrate resistant prostate cancer (CRPC) is the fatal-form of prostate cancer and remains androgen dependent. The reactivation of the androgen axis occurs due to adaptive intratumoral androgen biosynthesis which can be driven by adrenal androgens and/or by changes in the androgen receptor (AR) including AR gene amplification. These mechanisms are targeted with P450c17 inhibitors e.g., abiraterone acetate and AR super-antagonists e.g., enzalutamide, respectively. Clinical experience indicates that with either agent an initial response is followed by drug resistance and the patient clinically progresses on these agents. This article reviews the mechanisms of intrinsic and acquired drug resistance that target the androgen axis and how this might be surmounted.

Li Z, Bishop AC, Alyamani M, et al.
Conversion of abiraterone to D4A drives anti-tumour activity in prostate cancer.
Nature. 2015; 523(7560):347-51 [PubMed] Free Access to Full Article Related Publications
Prostate cancer resistance to castration occurs because tumours acquire the metabolic capability of converting precursor steroids to 5α-dihydrotestosterone (DHT), promoting signalling by the androgen receptor and the development of castration-resistant prostate cancer. Essential for resistance, DHT synthesis from adrenal precursor steroids or possibly from de novo synthesis from cholesterol commonly requires enzymatic reactions by 3β-hydroxysteroid dehydrogenase (3βHSD), steroid-5α-reductase (SRD5A) and 17β-hydroxysteroid dehydrogenase (17βHSD) isoenzymes. Abiraterone, a steroidal 17α-hydroxylase/17,20-lyase (CYP17A1) inhibitor, blocks this synthetic process and prolongs survival. We hypothesized that abiraterone is converted by an enzyme to the more active Δ(4)-abiraterone (D4A), which blocks multiple steroidogenic enzymes and antagonizes the androgen receptor, providing an additional explanation for abiraterone's clinical activity. Here we show that abiraterone is converted to D4A in mice and patients with prostate cancer. D4A inhibits CYP17A1, 3βHSD and SRD5A, which are required for DHT synthesis. Furthermore, competitive androgen receptor antagonism by D4A is comparable to the potent antagonist enzalutamide. D4A also has more potent anti-tumour activity against xenograft tumours than abiraterone. Our findings suggest an additional explanation-conversion to a more active agent-for abiraterone's survival extension. We propose that direct treatment with D4A would be more clinically effective than abiraterone treatment.

Henríquez-Hernández LA, Valenciano A, Foro-Arnalot P, et al.
Genetic variations in genes involved in testosterone metabolism are associated with prostate cancer progression: A Spanish multicenter study.
Urol Oncol. 2015; 33(7):331.e1-7 [PubMed] Related Publications
BACKGROUND: Prostate cancer (PCa) is an androgen-dependent disease. Nonetheless, the role of single nucleotide polymorphisms (SNPs) in genes encoding androgen metabolism remains an unexplored area.
PURPOSE: To investigate the role of germline variations in cytochrome P450 17A1 (CYP17A1) and steroid-5α-reductase, α-polypeptides 1 and 2 (SRD5A1 and SRD5A2) genes in PCa.
PATIENTS AND METHODS: In total, 494 consecutive Spanish patients diagnosed with nonmetastatic localized PCa were included in this multicenter study and were genotyped for 32 SNPs in SRD5A1, SRD5A2, and CYP17A1 genes using a Biotrove OpenArray NT Cycler. Clinical data were available. Genotypic and allelic frequencies, as well as haplotype analyses, were determined using the web-based environment SNPator. All additional statistical analyses comparing clinical data and SNPs were performed using PASW Statistics 15.
RESULTS: The call rate obtained (determined as the percentage of successful determinations) was 97.3% of detection. A total of 2 SNPs in SRD5A1-rs3822430 and rs1691053-were associated with prostate-specific antigen level at diagnosis. Moreover, G carriers for both SNPs were at higher risk of presenting initial prostate-specific antigen levels>20ng/ml (Exp(B) = 2.812, 95% CI: 1.397-5.657, P = 0.004) than those who are AA-AA carriers. Haplotype analyses showed that patients with PCa nonhomozygous for the haplotype GCTTGTAGTA were at an elevated risk of presenting bigger clinical tumor size (Exp(B) = 3.823, 95% CI: 1.280-11.416, P = 0.016), and higher Gleason score (Exp(B) = 2.808, 95% CI: 1.134-6.953, P = 0.026).
CONCLUSIONS: SNPs in SRD5A1 seem to affect the clinical characteristics of Spanish patients with PCa.

Werner R, Merz H, Birnbaum W, et al.
46,XY Gonadal Dysgenesis due to a Homozygous Mutation in Desert Hedgehog (DHH) Identified by Exome Sequencing.
J Clin Endocrinol Metab. 2015; 100(7):E1022-9 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: 46,XY disorders of sex development (DSD) comprise a heterogeneous group of congenital conditions. Mutations in a variety of genes can affect gonadal development or androgen biosynthesis/action and thereby influence the development of the internal and external genital organs.
OBJECTIVE: The objective of the study was to identify the genetic cause in two 46,XY sisters of a consanguineous family with DSD and gonadal tumor formation.
METHODS: We used a next-generation sequencing approach by exome sequencing. Electrophysiological and high-resolution ultrasound examination of peripheral nerves as well as histopathological examination of the gonads were performed.
RESULTS: We identified a novel homozygous R124Q mutation in the desert hedgehog gene (DHH), which alters a conserved residue among the three mammalian Hedgehog ligands sonic hedgehog, Indian hedgehog, and desert hedgehog. No other relevant mutations in DSD-related genes were encountered. The gonads of one patient showed partial gonadal dysgenesis with loss of Leydig cells in tubular areas with seminoma in situ and a hyperplasia of Leydig cell-like cells expressing CYP17A1 in more dysgenetic parts of the gonad. In addition, both patients suffer from a polyneuropathy. High-resolution ultrasound revealed a structural change of peripheral nerve structure that fits well to a minifascicle formation of peripheral nerves.
CONCLUSION: Mutations in DHH play a role in 46,XY gonadal dysgenesis and are associated with seminoma formation and a neuropathy with minifascicle formation. Gonadal dysgenesis in these cases may be due to impairment of Sertoli cell-Leydig cell interaction during gonadal development.

Salvi S, Casadio V, Conteduca V, et al.
Circulating cell-free AR and CYP17A1 copy number variations may associate with outcome of metastatic castration-resistant prostate cancer patients treated with abiraterone.
Br J Cancer. 2015; 112(10):1717-24 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: This study aimed to investigate copy number variations (CNVs) of CYP17A1 and androgen receptor (AR) genes in serum cell-free DNA collected before starting abiraterone in 53 consecutive patients with castration-resistant prostate cancer (CRPC).
METHODS: Serum DNA was isolated and CNVs were analysed for AR and CYP17A1 genes using Taqman copy number assays. The association between CNVs and progression-free/overall survival (PFS/OS) was evaluated by the Kaplan-Meier method and log-rank test.
RESULTS: Median PFS of patients with AR gene gain was 2.8 vs 9.5 months of non-gained cases (P < 0.0001). Patients with CYP17A1 gene gain had a median PFS of 2.8 months vs 9.2 months in the non-gained patients (P = 0.0014). A lower OS was reported in both cases (AR: P < 0.0001; CYP17A1: P = 0.0085). Multivariate analysis revealed that PSA decline ⩾ 50%, AR and CYP17A1 CNVs were associated with shorter PFS (P < 0.0001, P = 0.0004 and P = 0.0450, respectively), while performance status, PSA decline ⩾ 50%, AR CNV and DNA concentration were associated with OS (P = 0.0021, P = 0.0014, P = 0.0026 and P = 0.0129, respectively).
CONCLUSIONS: CNVs of AR and CYP17A1 genes would appear to be associated with outcome of CRPC patients treated with abiraterone.

Giacinti S, Bassanelli M, Aschelter AM, et al.
Resistance to abiraterone in castration-resistant prostate cancer: a review of the literature.
Anticancer Res. 2014; 34(11):6265-9 [PubMed] Related Publications
Persistent androgen signaling is functionally significant in castration-resistant prostate cancer (CRPC) and it is actually considered a validated therapeutic target. Residual intra-tumoral androgens compensate for the effects of androgen ablation, activating the androgen receptor (AR), AR-mediated gene expression and driving CRPC. The intra-tumoral biosynthesis of androgens takes place in different ways and cytochrome P450 17A1 (CYP17A1) has a crucial role in this context. Abiraterone, a CYP17A1 inhibitor, has shown impressive results in pre- and post-chemotherapy settings, prolonging the survival of patients with CRPC. However, not all patients respond to the treatment and most responders develop resistance, with a widely variable duration of response. Although many hypotheses are emerging, the mechanisms of resistance to abiraterone treatment have not yet been elucidated. The aim of the present review is to describe the main data currently available on resistance to abiraterone.

Toren PJ, Kim S, Pham S, et al.
Anticancer activity of a novel selective CYP17A1 inhibitor in preclinical models of castrate-resistant prostate cancer.
Mol Cancer Ther. 2015; 14(1):59-69 [PubMed] Related Publications
VT-464 is a novel, nonsteroidal, small-molecule CYP17A1 inhibitor with 17,20-lyase selectivity. This study evaluates the anticancer activity of VT-464 compared with abiraterone (ABI) in castrate-resistant prostate cancer cell lines and xenograft models that are enzalutamide (ENZ)-responsive (C4-2) or ENZ-resistant (MR49C, MR49F). In vitro, androgen receptor (AR) transactivation was assessed by probasin luciferase reporter, whereas AR and AR-regulated genes and steroidogenic pathway enzymes were assessed by Western blot and/or qRT-PCR. The MR49F xenograft model was used to compare effects of oral VT-464 treatment to vehicle and abiraterone acetate (AA). Steroid concentrations were measured using LC-MS chromatography. VT-464 demonstrated a greater decrease in AR transactivation compared with ABI in C4-2 and both ENZ-resistant cell lines. At the gene and protein level, VT-464 suppressed the AR axis to a greater extent compared with ABI. Gene transcripts StAR, CYP17A1, HSD17B3, and SRD5A1 increased following treatment with ABI and to a greater extent with VT-464. In vivo, intratumoral androgen levels were significantly lower after VT-464 or AA treatment compared with vehicle, with the greatest decrease seen with VT-464. Similarly, tumor growth inhibition and PSA decrease trends were greater with VT-464 than with AA. Finally, an AR-antagonist effect of VT-464 independent of CYP17A1 inhibition was observed using luciferase reporter assays, and a direct interaction was confirmed using an AR ligand binding domain biolayer interferometry. These preclinical results suggest greater suppression of the AR axis with VT-464 than ABI that is likely due to both superior selective suppression of androgen synthesis and AR antagonism.

Han JH, Lee YS, Kim HJ, et al.
Association between cytochrome CYP17A1, CYP3A4, and CYP3A43 polymorphisms and prostate cancer risk and aggressiveness in a Korean study population.
Asian J Androl. 2015 Mar-Apr; 17(2):285-91 [PubMed] Free Access to Full Article Related Publications
In this study, we evaluated genetic variants of the androgen metabolism genes CYP17A1, CYP3A4, and CYP3A43 to determine whether they play a role in the development of prostate cancer (PCa) in Korean men. The study population included 240 pathologically diagnosed cases of PCa and 223 age-matched controls. Among the 789 single-nucleotide polymorphism (SNP) database variants detected, 129 were reported in two Asian groups (Han Chinese and Japanese) in the HapMap database. Only 21 polymorphisms of CYP17A1, CYP3A4, and CYP3A43 were selected based on linkage disequilibrium in Asians (r2 = 1), locations (SNPs in exons were preferred), and amino acid changes and were assessed. In addition, we performed haplotype analysis for the 21 SNPs in CYP17A1, CYP3A4, and CYP3A43 genes. To determine the association between genotype and haplotype distributions of patients and controls, logistic analyses were carried out, controlling for age. Twelve sequence variants and five major haplotypes were identified in CYP17A1. Five sequence variants and two major haplotypes were identified in CYP3A4. Four sequence variants and four major haplotypes were observed in CYP3A43. CYP17A1 haplotype-2 (Ht-2) (odds ratio [OR], 1.51; 95% confidence interval [CI], 1.04-2.18) was associated with PCa susceptibility. CYP3A4 Ht-2 (OR: 1.87; 95% CI: 1.02-3.43) was associated with PCa metastatic potential according to tumor stage. rs17115149 (OR: 1.96; 95% CI: 1.04-3.68) and CYP17A1 Ht-4 (OR: 2.01; 95% CI: 1.07-4.11) showed a significant association with histologic aggressiveness according to Gleason score. Genetic variants of CYP17A1 and CYP3A4 may play a role in the development of PCa in Korean men.

Robitaille CN, Rivest P, Sanderson JT
Antiandrogenic mechanisms of pesticides in human LNCaP prostate and H295R adrenocortical carcinoma cells.
Toxicol Sci. 2015; 143(1):126-35 [PubMed] Related Publications
Several pesticides suspected or known to have endocrine disrupting effects were screened for pro- or antiandrogenic properties by determining their effects on proliferation, prostatic-specific antigen (PSA) secretion and androgen receptor (AR) expression, and AR phosphorylation in androgen-dependent LNCaP human prostate cancer cells, as well as on the expression and catalytic activity of the enzyme CYP17 in H295R human adrenocortical carcinoma cells, an in vitro model of steroidogenesis. Effects on SRD5A gene expression were determined in both cell lines. Benomyl, vinclozolin, and prochloraz, but not atrazine, concentration dependently (1-30 μM) decreased dihydrotestosterone (DHT)-stimulated proliferation of LNCaP cells. All pesticides except atrazine decreased DHT-stimulated PSA secretion, AR nuclear accumulation, and AR phosphorylation on serines 81 and 213 in LNCaP cells. Benomyl and prochloraz, but not vinclozolin or atrazine, decreased levels of CYP17 gene and protein expression, as well as catalytic activity in H295R cells. In the case of prochloraz, some of these effects corresponded with cytotoxicity. H295R cells expressed AR protein and SRD5A1, but not SRD5A2 transcripts. SRD5A1 gene expression in H295R cells was increased by 10 nM DHT, whereas in LNCaP cells significant induction was observed by 0.1 nM DHT. AR protein expression in H295R cells was not increased by DHT. Vinclozolin decreased DHT-induced SRD5A1 gene expression in LNCaP, but not H295R cells, indicating a functional difference of AR between the cell lines. In conclusion, pesticides may exert antiandrogenic effects through several mechanisms that are cell type-specific, including AR antagonism and down-regulation or catalytic inhibition of androgen biosynthetic enzymes, such as CYP17 and SRD5A1.

Li L, Gu ZP, Bo QM, et al.
Association of CYP17A1 gene -34T/C polymorphism with polycystic ovary syndrome in Han Chinese population.
Gynecol Endocrinol. 2015; 31(1):40-3 [PubMed] Related Publications
PURPOSE: To investigate the influence of the cytochrome P450 17α (CYP17A1) gene -34T/C polymorphism in the pathogenesis of polycystic ovary syndrome (PCOS) in Han Chinese population.
METHODS: Three-hundred eighteen patients with PCOS and 306 controls were recruited and the CYP17A1 -34T/C polymorphism was genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Furthermore, the relationship of CYP17A1 -34T/C polymorphism and clinical feature parameters of PCOS patients was also analyzed.
RESULTS: The prevalence rates of CYP17A1 genotype TT, TC and CC were 49.69%, 43.71% and 6.6% in the case group and those were 44.77%, 46.08% and 9.15% in the control group. The frequencies of CYP17A1 T and C alleles were 71.54% and 28.46% in the case group, and those were 67.81% and 32.19% in the control group. Neither the genotypic nor the allelic distribution was significantly different between the cases and controls. However, the PCOS patients with the genotype of CC had significantly higher total testosterone levels and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) than those with the genotype of TT or TC.
CONCLUSIONS: The CYP17A1 gene -34T/C polymorphism might not be directly correlated with the PCOS, but might influence PCOS via the association of testosterone level and the HOMA-IR.

Sissung TM, Price DK, Del Re M, et al.
Genetic variation: effect on prostate cancer.
Biochim Biophys Acta. 2014; 1846(2):446-56 [PubMed] Free Access to Full Article Related Publications
The crucial role of androgens in the development of prostate cancer is well established. The aim of this review is to examine the role of constitutional (germline) and tumor-specific (somatic) polymorphisms within important regulatory genes of prostate cancer. These include genes encoding enzymes of the androgen biosynthetic pathway, the androgen receptor gene, genes that encode proteins of the signal transduction pathways that may have a role in disease progression and survival, and genes involved in prostate cancer angiogenesis. Characterization of deregulated pathways critical to cancer cell growth have lead to the development of new treatments, including the CYP17 inhibitor abiraterone and clinical trials using novel drugs that are ongoing or recently completed [1]. The pharmacogenetics of the drugs used to treat prostate cancer will also be addressed. This review will define how germline polymorphisms are known affect a multitude of pathways, and therefore phenotypes, in prostate cancer etiology, progression, and treatment.

Gupta E, Guthrie T, Tan W
Changing paradigms in management of metastatic Castration Resistant Prostate Cancer (mCRPC).
BMC Urol. 2014; 14:55 [PubMed] Free Access to Full Article Related Publications
Recently, the standard of care for metastatic Castration Resistant Prostate Cancer (mCRPC) has changed considerably. Persistent androgen receptor (AR) signaling has been identified as a target for novel therapies and reengages the fact that AR continues to be the primary target responsible for metastatic prostate cancer. Androgen receptor gene amplification and over expression have been found to result in a higher concentration of androgen receptors on tumor cells, making them extremely sensitive to low levels of circulating androgens. Additionally, prostate cancer cells are able to maintain dihydrotestosterone (DHT) concentration in excess of serum concentrations to support tumor growth. For many years ketoconazole was the only CYP17 inhibitor that was used to treat mCRPC. However, significant toxicities limit its use. Newly approved chemotherapeutic agents such as Abiraterone (an oral selective inhibitor of CYP17A), which blocks androgen biosynthesis both within and outside the prostate cancer cells), and enzalutamide (blocks AR signaling) have improved overall survival. There are also ongoing phase III trials for Orteronel (TAK- 700), ARN- 509 and Galeterone (TOK-001), which targets androgen signaling. In this review, we will present the rationale for the newly approved hormonal treatments, their indications and complications, and we will discuss ongoing trials that are being done to improve the efficacy of the approved agents. Finally, we will talk about the potential upcoming hormonal treatments for mCRPC.

Kim W, Jones JO, Diamond M, et al.
Inhibition of the androgen receptor by mineralocorticoids at levels physiologically achieved in serum in patients treated with abiraterone acetate.
Prostate Cancer Prostatic Dis. 2014; 17(3):292-9 [PubMed] Related Publications
BACKGROUND: Abiraterone acetate (AA), a highly potent CYP17A1 inhibitor, has demonstrated marked clinical benefit in patients with metastatic castration-resistant prostate cancer (CRPC). Phase I trials of AA without prednisone showed significant elevation of serum mineralocorticoid concentrations. The aim of this study was to elucidate the biological significance of elevated mineralocorticoid levels on androgen receptor (AR) activity in prostate cancer (PC) cells.
METHODS: Fluorescence resonance energy transfer (FRET) assay was used to assess the effect of mineralocorticoids on androgen-induced conformational change of the AR. LAPC4, LNCaP and LN-AR cells that were cultured and treated with androgens were exposed to mineralocorticoids at varying concentrations, including levels measured in the serum of AA-treated patients in a phase I trial. AR-dependent transcriptional activity and cell growth were measured in these cell lines to determine the biological impact of mineralocorticoids on PC cells.
RESULTS: Corticosterone (CS) and deoxycorticosterone (DOC) inhibited androgen-induced conformational change of the AR in the FRET assay. CS inhibited AR-dependent transcriptional activity and cell growth at concentrations comparable to those measured in the serum of AA-treated patients. DOC inhibited AR transcriptional activity and cell growth at 10-fold greater concentrations than measured in the serum of AA-treated patients.
CONCLUSIONS: Mineralocorticoids directly inhibit androgen-induced conformational change of the AR. CS inhibits AR transcriptional activity and PC cell growth at concentrations found in the serum of patients treated with AA. Further investigation of the potential therapeutic implications of mineralocorticoids in AA-treated CRPC patients is warranted.

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