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MicroRNA (miRNA) deregulation in prostate cancer (PCa) contributes to PCa initiation and metastatic progression. To comprehensively define the cancer-associated changes in miRNA targeting and function in commonly studied models of PCa, we performed photoactivatable ribonucleoside-enhanced cross-linking immunoprecipitation of the Argonaute protein in a panel of PCa cell lines modeling different stages of PCa progression. Using this comprehensive catalogue of miRNA targets, we analyzed miRNA targeting on known drivers of PCa and examined tissue-specific and stage-specific pathway targeting by miRNAs. We found that androgen receptor is the most frequently targeted PCa oncogene and that miR-148a targets the largest number of known PCa drivers. Globally, tissue-specific and stage-specific changes in miRNA targeting are driven by homeostatic response to active oncogenic pathways. Our findings indicate that, even in advanced PCa, the miRNA pool adapts to regulate continuing alterations in the cancer genome to balance oncogenic molecular changes. These findings are important because they are the first to globally characterize miRNA changes in PCa and demonstrate how the miRNA target spectrum responds to staged tumorigenesis., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

Estrogens and antioxidants indirectly alleviate telomere attrition. However, available clinical data on the association between hormone exposure and telomere length are inconclusive. In the present study, we examined the effects of exogenous estrogen use and of some genetic factors implicated in estrogen metabolism and oxidative stress response on mean leukocyte telomere length. We studied 259 postmenopausal women. Genotyping was conducted for CYP1B1 (rs1056836), COMT (rs4680), GSTP1 (rs1695), MnSOD (rs4880), KRAS (rs61764370), and MTHFR (rs1801133 and rs1801131) polymorphisms. Mean leukocyte telomere length was measured using a quantitative real-time PCR assay. In multivariate analysis we found no association between oral contraceptives or hormone replacement therapy (HRT) and mean leukocyte telomere length. The presence of variant alleles in CYP1B1, KRAS and MTHFR genes was statistically significantly associated with shorter mean leukocyte telomere length. Further, the data provided evidence for the effect modification of the association between HRT and mean leukocyte telomere length by the CYP1B1, KRAS and MTHFR genotypes. Our findings suggest that functionally relevant genetic variants within estrogen and folate metabolic pathways may influence telomere length. We propose these genetic factors should be taken into consideration when interpreting associations between hormone exposure and telomere length., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

The objective of the present study was to evaluate the influence of TAAAA repeat allele length on the levels of serum sex hormone binding globulin (SHBG) and cardiovascular risk factors in patients with polycystic ovary syndrome (PCOS). The study included 91 females with PCOS and 99 healthy controls. Phenotypic hyperandrogenism, body mass index and waist‑to‑hip ratio (WHR) were recorded. Hormonal profiles, fasting insulin and glucose levels, lipid profiles and C‑reactive protein (CRP) levels were measured. Genotyping of TAAAA repeat polymorphisms in the SHBG gene was performed. No significant difference was found in the frequency and distribution of TAAAA repeat alleles between PCOS patients and controls (P=0.739). In PCOS patients, SHBG levels were inversely correlated with serum C‑reactive protein (CRP) levels (R=-0.489, P<0.001). PCOS patients with long TAAAA repeat alleles had significantly lower serum SHBG and free testosterone levels, yet higher CRP levels than patients with short allele repeats. A multiple linear regression model using the number of TAAAA repeats, waist‑to‑hip ratio, a homeostatic model assessment of insulin resistance and age as independent predictors explained 44.8% of the variability in serum SHBG levels. In this model, TAAAA repeat polymorphism was found to be the only reliable predictor of serum SHBG levels (P<0.001). In conclusion, the TAAAA repeat polymorphism was shown to not be a major determinant of the PCOS status, although it influenced serum SHBG levels in females with PCOS. A strong independent association existed between serum SHBG and CRP levels. CRP is an established risk factor of cardiovascular disease and a marker of low‑grade inflammation, typical of atherogenesis. This may be one of the pathways by which low SHBG levels affect cardiovascular risk.

Purpose: Uveal melanoma (UM) tumors require large doses of radiation therapy (RT) to achieve tumor ablation, which frequently results in damage to adjacent normal tissues, leading to vision-threatening complications. Approximately 50% of UM patients present with activating somatic mutations in the gene encoding for G protein αq-subunit (GNAQ), which lead to constitutive activation of downstream pathways, including protein kinase C (PKC). In this study, we investigated the impact of small-molecule PKC inhibitors bisindolylmaleimide I (BIM) and sotrastaurin (AEB071), combined with ionizing radiation (IR), on survival in melanoma cell lines., Methods: Cellular radiosensitivity was determined by using a combination of proliferation, viability, and clonogenic assays. Cell-cycle effects were measured by flow cytometry. Transcriptomic and proteomic profiling were performed by quantitative real-time PCR, reverse-phase protein array analysis, and immunofluorescence., Results: We found that the PKC inhibitors combined with IR significantly decreased the viability, proliferation, and clonogenic potential of GNAQ(mt), but not GNAQ(wt)/BRAF(mt) cells, compared with IR alone. Combined treatment increased the antiproliferative and proapoptotic effects of IR in GNAQ(mt) cells through delayed DNA-damage resolution and enhanced induction of proteins involved in cell-cycle arrest, cell-growth arrest, and apoptosis., Conclusions: Our preclinical results suggest that combined modality treatment may allow for reductions in the total RT dose and/or fraction size, which may lead to better functional organ preservation in the treatment of primary GNAQ(mt) UM. These findings suggest future clinical trials combining PKC inhibitors with RT in GNAQ(mt) UM warrant consideration.

Insulin resistance is one of the key factors in the pathogenesis of polycystic ovary syndrome (PCOS). The peroxisome proliferator-activated receptor gamma (PPARG) plays a role in the regulation of insulin sensitivity. The aim of the present study was to establish a possible association of the PPARG Pro12Ala polymorphism with PCOS and its effect on family and personal history, as well as on the metabolic and endocrine parameters in PCOS patients. A total of 151 PCOS patients and 179 healthy women of reproductive age were enrolled. History, body mass index (BMI), waist-to-hip ratio and the presence of phenotypic hyperandrogenism were recorded. Hormonal, metabolic and biochemical profiles were assessed. A molecular analysis for the genetic polymorphism was performed. One third (29.8%) of the PCOS patients were found to be carriers of at least one variant of the Ala allele (X/Ala), while 70.2% carried two wild-type Pro alleles (Pro/Pro), with an equal distribution observed in the control group. The PCOS patients carrying the X/Ala alleles exhibited lower serum fasting insulin levels, homeostatic model assessment of insulin resistance (HOMA-IR) and BMI compared to Pro/Pro carriers. This finding was significant only in the lean PCOS group. The polymorphic genotype exerted no effect on history, hormonal and clinical hyperandrogenism, lipid status or C-reactive protein, leptin, adiponectin, resistin and ghrelin serum levels in women with PCOS. In conclusion, although the PPARG Pro12Ala polymorphism is not a major determinant of PCOS in the Croatian population, it may exert a positive effect on insulin sensitivity and BMI. As these associations were recorded exclusively in the lean group of patients with PCOS, this polymorphism potentially contributes to a protective role against hyperinsulinemia and obesity.

Background: In prostate cancer patients treated with androgen deprivation therapy (ADT) and radiation therapy (RT), a pre-RT PSA level 0.5 ng ml(-1), determined after neoadjuvant ADT and before RT, predicts for worse survival measures. The present study sought to identify patient, tumor and treatment characteristics associated with the pre-RT PSA in prostate cancer patients., Methods: We reviewed the charts of all patients diagnosed with intermediate- and high-risk prostate cancer and treated with a combination of neoadjuvant (median, 2.2 and 2.5 months, respectively), concurrent, and adjuvant ADT and RT between 1990 and 2011., Results: A total of 170 intermediate- and 283 high-risk patients met inclusion criteria. On multivariate analysis, both intermediate- and high-risk patients with higher pre-treatment PSA (iPSA) were significantly less likely to achieve a pre-RT PSA <0.5 ng ml(-1) (iPSA 10.1-20 ng ml(-1): P=0.005 for intermediate risk; iPSA 10.1-20 ng ml(-1): P=0.005, iPSA >20 ng ml(-1): P<0.001 for high risk). High-risk patients undergoing total androgen blockade were more likely to achieve a pre-RT PSA <0.5 ng ml(-1) (P=0.031). We observed an interaction between race and type of neoadjuvant ADT (P=0.074); whereas African-American men on total androgen blockade reached pre-RT PSA <0.5 ng ml(-1) as frequently as other men on total androgen blockade (P=0.999), African-American men on luteinizing hormone-releasing hormone (LH-RH) agonist monotherapy/orchiectomy were significantly less likely to reach pre-RT PSA <0.5 ng ml(-1) compared with other men on LH-RH monotherapy/orchiectomy (P=0.001)., Conclusions: Our findings suggest that total androgen blockade in the neoadjuvant period may be beneficial compared with LH-RH monotherapy for achieving a pre-RT PSA <0.5 ng ml(-1) in African-American men with high-risk prostate cancer. In addition, men with higher iPSA are more likely to have a pre-RT PSA greater than 0.5 ng ml(-1) in response to neoadjuvant ADT and are therefore candidates for clinical trials testing newer, more aggressive hormone-ablative therapies.

Obesity and insulin resistance is a common finding in patients with polycystic ovary syndrome (PCOS). Significant number of PCOS women experience insulin resistance that is irrespective of the degree of obesity suggesting possible genetic basis. Therefore, several polymorphisms of the genes encoding for the insulin (INS), insulin receptor (INSR) or insulin receptor substrates (IRS) involved in postreceptor signaling have been explored for their association with abnormal sensitivity to insulin in PCOS. The aim of the present study was to determine whether selected polymorphisms of INS, INSR and IRS-1 are associated with the development of PCOS as well as with increased insulin resistance in Croatian women with PCOS. The study enrolled 150 women with PCOS and 175 control women. The diagnosis of PCOS was based on Rotterdam consensus criteria. Each subject underwent an evaluation of body mass index (BMI), hirsutism, acne and menstrual cycle abnormalities as well as follicular stimulating hormone (FSH), luteinizing hormone (LH), total and free testosterone, androstendione, dehydroepiandrosterone sulphate (DHEAS), sex hormone binding globulin (SHBG), fasting glucose and fasting insulin. Insulin resistance (IR) was quantified using the homeostatic model assessment of IR (HOMA-IR). Molecular analyses for the genetic polymorphisms were preformed. There was a significant difference in clinical and biochemical characteristics of the studied groups except for BMI and fasting glucose levels. No significant differences were observed in the genotype and allele distribution of the VNTR INS, C/T INSR, Gly792Arg IRS-1 polymorphisms between cases and controls. Moreover, no association was found between VNTR INS, C/T INSR and Gly792Arg IRS-1 polymorphism and parameters of insulin resistance in PCOS patients. In conclusion, our data does not support an association between VNTR INS, C/T INSR and Gly792Arg IRS-1 polymorphism and susceptibility to PCOS or insulin resistance in Croatian women with PCOS.

Purpose: The aim of the study was to evaluate the prognostic value of prostate-specific antigen (PSA) response to neoadjuvant androgen deprivation therapy (ADT) prior to dose-escalated radiation therapy (RT) and long-term ADT in high-risk prostate cancer., Methods and Materials: We reviewed the charts of all patients diagnosed with high-risk prostate cancer and treated with a combination of long-term ADT (median, 24 months) and dose-escalated (median, 75.6 Gy) RT between 1990 and 2007. The associations among patient, tumor, and treatment characteristics with biochemical response to neoadjuvant ADT and their effects on failure-free survival (FFS), time to distant metastasis (TDM), prostate cancer-specific mortality (PCSM) and overall survival (OS) were examined., Results: A total of 196 patients met criteria for inclusion. Median follow-up time for patients alive at last contact was 7.0 years (range, 0.5-18.1 years). Multivariate analysis identified the pre-RT PSA concentration (<0.5 vs ≥0.5 ng/mL) as a significant independent predictor of FFS (P=.021), TDM (P=.009), PCSM (P=.039), and OS (P=.037). On multivariate analysis, pretreatment PSA (iPSA) and African-American race were significantly associated with failure to achieve a pre-RT PSA of <0.5 ng/mL., Conclusions: For high-risk prostate cancer patients treated with long-term ADT and dose-escalated RT, a pre-RT PSA level≥0.5 ng/mL after neoadjuvant ADT predicts for worse survival measures. Both elevated iPSA and African-American race are associated with increased risk of having a pre-RT PSA level≥0.5 ng/mL. These patients should be considered for clinical trials that test newer, more potent androgen-depleting therapies such as abiraterone and MDV3100 in combination with radiation., (Copyright © 2013 Elsevier Inc. All rights reserved.)

The purpose of this study is to investigate whether BRCA1 promoter methylation is associated with poorer outcome in sporadic breast cancer cases treated with tamoxifen. BRCA1 promoter methylation was determined by bisulfite pyrosequencing in two groups of sporadic breast cancer patients, systemically untreated (N = 497) and treated with adjuvant tamoxifen (N = 497). Associations of BRCA1 promoter methylation with clinopathological characteristics and the effect of BRCA1 promoter methylation on time to first recurrence (TTR) and overall survival (OS) were examined. No significant differences were observed between BRCA1 promoter methylation and clinopathological characteristics in untreated and tamoxifen-treated groups. Cut point analysis did not find any promising cut point for BRCA1 promoter methylation that would differentially influence TTR and OS in untreated and tamoxifen-treated group. Using the median (2.53 %) and an arbitrary value of 10 % as a cut point for methylation, we still found no significant effect of BRCA1 promoter methylation on TTR and OS in untreated and tamoxifen-treated group. Despite data suggesting that BRCA1 levels impact estrogen receptor response to tamoxifen, our results indicate that BRCA1 promoter methylation is not associated with poorer outcome in sporadic breast cancer cases treated with tamoxifen.

Background: A single nucleotide polymorphism located in the 3'-untranslated region of the KRAS oncogene (KRAS variant; rs61764370) disrupts a let-7 miRNA binding and was recently reported to act as a genetic marker for increased risk of developing human cancers. We aimed to investigate an association of the KRAS variant with sporadic and familial breast cancer and breast tumor characteristics., Methods: Genotyping was accomplished in 530 sporadic postmenopausal breast cancer cases, 165 familial breast cancer cases (including N = 29, who test positive for BRCA1/2 mutations) and 270 postmenopausal control women using the flurogenic 5' nuclease assay. Information on hormone replacement therapy (HRT) use and tumor characteristics in sporadic breast cancer cases was ascertained from a postal questionnaire and pathology reports, respectively. Associations between the KRAS genotype and breast cancer or breast tumor characteristics were assessed using chi-square test and logistic regression models., Results: No evidence of association was observed between the KRAS variant and risk of sporadic and familial breast cancer - either among BRCA carriers or non-BRCA carriers. The KRAS variant was statistically significantly more often associated with human epidermal growth factor receptor 2 (HER2) - positive tumors and tumors of higher histopathologic grade. However, both associations were detected only in HRT users., Conclusion: Our data do not support the hypothesis that the KRAS variant rs61764370 is implicated in the aetiology of sporadic or of familial breast cancer. In postmenopausal women using HRT, the KRAS variant might lead to HER2 overexpressed and poorly-differentiated breast tumors, both indicators of a worse prognosis.

Hyperandrogenemia has been the most consistent feature of polycystic ovary syndrome (PCOS). Androgens exert their effects through androgen receptors (ARs). The expansion of the codon CAG trinucleotide repeat polymorphism in exon 1 of the AR gene represents a type of genetic alteration associated with changes in the AR gene function. The purpose of this study was to establish a possible association of the AR gene CAG repeat length polymorphism with PCOS, and its influence on clinical and biochemical androgen traits. Two hundred and fourteen Croatian women with PCOS and 209 healthy control women of reproductive age were enrolled. Phenotypic hyperandrogenism, BMI and waist to hip ratio were recorded. Hormonal profiles, fasting insulin and glucose levels were measured on cycle days 3-5. Genotyping of the CAG repeat polymorphism in the AR gene was performed. We found no significant difference in the mean CAG repeat number between the PCOS patients and controls (22.1±3.4 vs. 21.9±3.2, P=0.286). There was a positive correlation between the CAG repeat length and total testosterone (TT) in the PCOS group (R=0.225, P=0.015). A multiple linear regression model using mean CAG repeat length, BMI, age and HOMA-IR as predictors explained 8.5% (adjusted R²) of the variability in serum TT levels. In this model the CAG repeat polymorphism was found to be a significant predictor of serum TT levels in PCOS patients (P=0.015). The logistic regression analysis revealed that the CAG repeat length is not a significant predictor of hirsutism and acne status (P=0.921 and P=0.437, respectively). The model was adjusted for serum TT, free testosterone, androstendione and DHEAS levels as independent variables, which were also not found to be significant predictors of hirsutism (P=0.687, P=0.194, P=0.675 and P=0.938, respectively) or acne status (P=0.594, P=0.095, P=0.290 and P=0.151, respectively). In conclusion, the AR CAG repeat polymorphism is not a major determinant of PCOS in the Croatian population, but it is a predictor of serum TT level variability in women with PCOS., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The aim of this study was to further elucidate the influence of HRT use, regarding duration, regimen and route of administration, on breast tumor characteristics. We evaluated the associations between HRT use and breast tumor characteristics in 530 postmenopausal women diagnosed with invasive breast cancer. Detailed information on HRT use and mammographic attendance were collected through a postal questionnaire. Adjusted odds ratios and 95% confidence intervals were calculated using logistic regression. Tumors in HRT users were significantly smaller, more often of ductal histologic type and with lower grade and lower mitotic index compared to tumors in nonusers. Tumor characteristics did not vary significantly by HRT duration, regimen and route of administration, except for mitotic index, which was more often of score 2 in long-term users, and of score 3 in short-term users. Higher mammographic surveillance among HRT users did not explain our results. We conclude that tumors in HRT users have a more favorable prognostic profile regardless of duration, regimen and route of administration. These effects seem to be due to the influence of HRT on preexisting tumors causing their greater differentiation rather than earlier detection due to mammographic surveillance.

Objective: The aim of the study was to examine the influence of the use of hormone replacement therapy (HRT) and of some generally recognized risk factors on breast cancer risk among Slovenian postmenopausal women., Methods: Eligible women diagnosed with breast cancer and a control group of women of the same age and ethnicity were invited to participate in the case-control study via a personal letter and asked to complete a written questionnaire. Adjusted odds ratios and 95% confidence intervals were estimated using multivariate logistic regression analysis., Results: A total of 784 cases and 709 controls aged 50-69 years were enrolled. HRT use was inversely associated with breast cancer risk. The effect was most pronounced with the use of estrogen-only replacement therapy (odds ratio (OR) 0.51, 95% confidence interval (CI) 0.30-0.87). Longer duration of HRT use did not result in a significant change in risk (1 to <5 years of HRT use: OR 0.44, 95% CI 0.26-0.73; ≥ 5 years of HRT use: OR 0.51, 95% CI 0.30-0.87). Obesity (25 ≤ body mass index <30 kg/m(2): OR 1.34, 95% CI 1.04-1.73; body mass index ≥ 30 kg/m(2): OR 1.89, 95% CI 1.36-2.63), smoking ≥ 10 cigarettes per day (OR 1.70, 95% CI 1.20-2.43), and any first-degree relative with breast or ovarian cancer (OR 1.52, 95% CI 1.11-2.08) were positively associated with breast cancer risk., Conclusions: Our analysis revealed some differences from the previously published literature, which might reflect underlying demographic changes. Comprehensive medical care in HRT users without pre-existing breast abnormalities probably reduces the incidence of new breast cancer cases in Slovenia.

Association between long-term hormone replacement therapy (HRT) use and increased risk of breast cancer is still under debate. Functionally relevant genetic variants within the estrogen metabolic pathway may alter exposure to exogenous sex hormones and affect the risk of postmenopausal breast cancer. We investigated the associations of common polymorphisms in 4 genes encoding key proteins of the estrogen metabolic pathway, duration of HRT use and their interactions with breast cancer risk. We studied 530 breast cancer cases and 270 controls of the same age and ethnicity participating in a case-control study of postmenopausal women. Duration of HRT use was ascertained through a postal questionnaire. Genotyping was conducted for CYP1B1 (rs1056836), COMT (rs4680), GSTP1 (rs1695) and MnSOD (rs4880) polymorphisms by PCR-based RFLP and TaqMan® allelic discrimination method. Adjusted odds ratios and 95% confidence intervals were calculated using logistic regression analysis. HRT use was significantly associated with decreased breast cancer risk (p<0.001). None of the polymorphisms studied was associated with breast cancer risk. A significant interaction was observed between MnSOD 47T>C and HRT use (pinteraction=0.036); the risk of breast cancer associated with long-term vs. short-term HRT use was decreased in women homozygous for the wild-type allele and increased in women with at least one variant allele of the MnSOD 47T>C polymorphism. Our results suggest that MnSOD 47T>C polymorphism in interaction with long-term HRT use may modify the risk of breast cancer.

Objective: Estrogen plays a key role in breast cancer development and functionally relevant genetic variants within the estrogen metabolic pathway are prime candidates for a possible association with breast cancer risk. We investigated the independent and the combined effects of commonly occurring polymorphisms in four genes encoding key proteins of estrogen metabolic pathway on their potential contribution to breast cancer risk., Methods: We studied 530 breast cancer cases and 270 controls of the same age and ethnicity participating in a case-control study of postmenopausal women. Genotyping was conducted for CYP1B1 (rs1056836), COMT (rs4680), GSTP1 (rs1695), and MnSOD (rs4880) polymorphisms by polymerase chain reaction based restriction fragment length polymorphism and TaqMan allelic discrimination method. Adjusted ORs and 95% CIs were calculated using logistic regression., Results: None of the 4 genetic variants examined contributed to breast cancer risk individually. When the combined effects of the risk genotypes were investigated, significant associations were observed among women with two high-risk genotypes in CYP1B1 and COMT (OR, 2.0; 95% CI, 1.1 to 3.5) and two high-risk genotypes in COMT and MnSOD (OR, 2.0; 95% CI, 1.0 to 3.8), compared to those with low-risk genotypes., Conclusion: Our results suggest that individual susceptibility to breast cancer incidence may be increased by combined effects of the high-risk genotypes in CYP1B1, COMT, and MnSOD estrogen metabolic genes.

Objective: The aim of the study was to analyze the impact of the rs2747648 genetic variant in the estrogen receptor alpha (ER1) gene affecting a putative miR-453-binding site on the risk of breast cancer in postmenopausal women. Furthermore, we examined if the risk changes in a subset of women on hormone replacement therapy (HRT)., Patients and Methods: We studied 530 breast cancer cases and 270 controls of the same age and ethnicity. Duration of HRT use was ascertained through a postal questionnaire. Genotyping was accomplished by TaqMan® allelic discrimination assay. The associations with breast cancer risk were assessed using logistic regression models., Results: The analysis did not reveal any association between the ER1 genetic variant and postmenopausal breast cancer risk, either ER-positive or ER-negative disease. Also, there was no association between the ER1 genetic variant and breast cancer risk in postmenopausal women receiving HRT., Conclusion: There may be an inverse association between the premenopausal women carrying the variant allele and breast cancer, but it was not detected in our analysis for the postmenopausal women, or for those on HRT.