Follicle-Stimulating Hormone Exacerbates Cardiovascular Disease in the Presence of Low or Castrate Testosterone Levels.

Low testosterone (T), common in aging men, associates with cardiovascular disease. We investigated whether follicle-stimulating hormone (FSH), which is affected by T, modulates the cardiovascular effects associated with low T or castration. FSHß-/-:low-density lipoprotein receptor (LDLR)-/- mice, untreated or castrated (orchiectomy, gonadotropin-releasing hormone agonist or antagonist), demonstrated significantly less atherogenesis compared with similarly treated LDLR-/- mice, but not following FSH delivery. Smaller plaque burden in LDLR-/- mice receiving gonadotropin-releasing hormone antagonists vs agonists were nullified in FSHß-/-:LDLR-/- mice. Atherosclerotic and necrotic plaque size and macrophage infiltration correlated with serum FSH/T. In patients with prostate cancer, FSH/T following androgen-deprivation therapy initiation predicted cardiovascular events. FSH facilitates cardiovascular disease when T is low or eliminated.

Low Serum Testosterone in Men with Newly Diagnosed Androgen-Deprivation Therapy-Naïve Prostate Cancer and Its Relationship to Cardiovascular Risk Factors: A RADICAL-PC Substudy.

PURPOSE: Cardiovascular disease is a common cause of death in prostate cancer patients. Low testosterone is associated with increased cardiovascular risk in the general male population. We investigated the relationship between serum testosterone, cardiovascular disease and risk factors in androgen-deprivation therapy-naïve prostate cancer patients. MATERIALS AND METHODS: We performed a cross-sectional analysis of a subgroup of 1,326 androgen-deprivation therapy-naïve men from RADICAL-PC (Role of Androgen-Deprivation Therapy In CArdiovascular Disease-A Longitudinal Prostate Cancer study) in whom serum testosterone was measured at baseline. RADICAL-PC is a prospective multicenter cohort study of men (2,565) enrolled within 1 year of prostate cancer diagnosis, or within 6 months of commencing androgen-deprivation therapy for the first time. Cardiovascular risk factors, cancer characteristics and total serum testosterone were collected at baseline. Low testosterone was defined as total serum testosterone <11 nmol/L (<320 ng/dL). A Framingham cardiovascular risk score ≥15 was considered high risk for future cardiovascular events. We performed logistic regression to calculate odds ratios for the association between testosterone and cardiovascular risk. RESULTS: Among 1,326 participants (median age 67 years, range 45-93), 553 (42%) had low testosterone. Low testosterone was associated with existing cardiovascular disease, diabetes, elevated hemoglobin A1c, obesity, hypertriglyceridemia, low high-density lipoprotein cholesterol, hypertension and Framingham score >15. Among patients with low testosterone, the odds ratio for high cardiovascular risk was 1.33 (1.02-1.73) after adjusting for ethnicity, education, alcohol use, cancer characteristics, physical activity and body mass index. CONCLUSIONS: Among androgen-deprivation therapy-naïve prostate cancer patients, low testosterone is common and associated with increased cardiovascular risk factors.

Characteristics of α2,3-sialyl N-glycosylated PSA as a biomarker for clinically significant prostate cancer in men with elevated PSA level.

BACKGROUND: The presence of glycosylated isoforms of prostate-specific antigen (PSA) in prostate cancer (PC) cells is a potential marker of their aggressiveness. We characterized the origin of α2,3-sialylated prostate-specific antigen (S23PSA) by tissue-based sialylation-related gene expression and studied the performance of S23PSA density (S23PSAD) alone and in combination with multiparametric magnetic resonance imaging (MRI) for the detection of clinically significant prostate cancer in men with elevated PSA. METHODS: Tissue-based quantification of S23PSA and sialyltransferase and sialidase gene expression was evaluated in 71 radical prostatectomy specimens. The diagnostic performance of S23PSAD was studied in 1099 men retrospectively enrolled in a multicenter systematic biopsy (SBx) cohort. We correlated the S23PSAD with Prostate Imaging Reporting and Data System (PI-RADS) scores in 98 men prospectively enrolled in a single-center MRI-targeted biopsy (MRI-TBx) cohort. The primary outcome was the PC-diagnostic performance of the S23PSAD, the secondary outcome was the avoidable biopsy rate of S23PSAD combined with DRE and total PSA (tPSA), and with or without PI-RADS. RESULTS: S23PSA was significantly higher in Gleason pattern 4 and 5 compared with benign prostate tissue. In the retrospective cohort, the performance of S23PSAD for detecting PC was superior to tPSA or PSA density (PSAD) (AUC: 0.7758 vs. 0.6360 and 0.7509, respectively). In the prospective cohort, S23PSAD was superior to tPSA, PSAD, and PI-RADS (AUC: 0.7725 vs. 0.5901, 0.7439 and 0.7305, respectively), and S23PSAD + PI-RADS + DRE + tPSA was superior to DRE + tPSA+PI-RADS with avoidance rate of MRI-TBx (13% vs. 1%) at 30% risk threshold. CONCLUSIONS: The diagnostic performance of S23PSAD was superior to conventional strategies but comparable to mpMRI.

Protective effect of pharmacological castration on metabolic perturbations and cardiovascular disease in the hyperglycemic male ApoE-/-:Ins2+/Akita mouse model.

BACKGROUND: Unlike in other mouse models of atherogenesis, it has recently been suggested that orchiectomy plays a role in accelerating atherosclerosis and inhibiting the progression of cardiovascular disease in the ApoE-/-:Ins2+/Akita mouse model of hyperglycemia. Androgen-deprivation therapy (ADT) is a common treatment for prostate cancer, a population with high prevalence of cardiovascular disease and its risk factors. Our objectives were to test and further characterize the effects of pharmacological castration which is currently the acceptable modality to deliver ADT in the clinic. METHODS: Male ApoE-/-:Ins2+/Akita mice received one of three modes of ADT (gonadotropin-releasing hormone (GnRH)-antagonist (degarelix), GnRH-agonist (leuprolide), or bilateral orchiectomy) and were compared to corresponding untreated control mice (n = 9-13/group). Mice were followed for 5 months. Body weight, fasting blood glucose, glucose tolerance, serum C-peptide, leptin, and testosterone levels along with atherosclerotic aortic plaque size and characteristics were determined. In a separate experiment, the survival of mice, untreated and on ADT, was determined. RESULTS: Castration was achieved for all three modes of ADT. However, degarelix-treated mice gained significantly less weight, had lower serum leptin levels and systolic blood pressure compared to orchiectomy and leuprolide-treated mice. ADT improved dysglycemia and atherosclerotic burden. GnRH-antagonist significantly improved survival compared to GnRH-agonist but not compared to orchiectomy. CONCLUSIONS: Further characterization of the ApoE-/-:Ins2+/Akita mouse model confirms that pharmacological ADT ameliorated metabolic syndrome and cardiovascular complications. Improved dysglycemia and atherosclerosis associated with increased survival which was longest after degarelix followed by orchiectomy.

Cardiovascular Morbidity in a Randomized Trial Comparing GnRH Agonist and GnRH Antagonist among Patients with Advanced Prostate Cancer and Preexisting Cardiovascular Disease.

PURPOSE: Androgen deprivation therapy may increase the risk of cardiovascular disease. Limited data suggest that GnRH (gonadotropin-releasing hormone) antagonist may be associated with a lower risk of cardiovascular disease than GnRH agonist. MATERIALS AND METHODS: We performed a phase II, randomized, open label study in men with prostate cancer and preexisting cardiovascular disease who were randomized to receive GnRH agonists or antagonists for 1 year. The primary outcome was endothelial function measured by the EndoPAT 2000 device (Itamar Medical, Caesarea, Israel). The predefined secondary outcome was a new cardiovascular event. Patients were followed for the development of cardiovascular disease, defined as death, myocardial infarction, a cerebrovascular event, percutaneous angioplasty with coronary stent insertion or hospitalizations due to cardiac events. RESULTS: A total of 80 patients were enrolled in study, including 41 and 39 who received GnRH antagonist and agonist, respectively. Patients in each arm had similar baseline characteristics. We did not detect a difference in the primary end point (endothelial function) between the groups (mean ± SD reactive hyperemia index 2.07 ± 0.15 vs 1.92 ± 0.11, p=0.42). However, during the trial period a new cardiovascular event (the secondary end point) developed in 15 patients. Of cases new major cardiovascular and cerebrovascular events developed in 9, including death in 2, myocardial infarction in 1, a cerebrovascular event in 2 and percutaneous angioplasty with coronary stent insertion in 4. Of the patients 20% randomized to GnRH agonist experienced a major cardiovascular and cerebrovascular event compared to 3% of those on GnRH antagonist (p=0.013). The absolute risk reduction in major cardiovascular and cerebrovascular events at 12 months using GnRH antagonist was 18.1% (95% CI 4.6-31.2, p=0.032). CONCLUSIONS: To our knowledge this is the first prospective study to test cardiovascular outcomes among patients with prostate cancer who received androgen deprivation therapy. No differences in the primary end point were noted between the study arms. However, the secondary end point revealed that patients treated with GnRH agonist experienced significantly more major cardiovascular and cerebrovascular events than those treated with GnRH antagonist. These phase II results suggest that in patients with prostate cancer who have preexisting cardiovascular disease selecting the androgen deprivation therapy modality may differentially affect cardiac outcomes.

Clinical significance of the LacdiNAc-glycosylated prostate-specific antigen assay for prostate cancer detection.

To reduce unnecessary prostate biopsies (Pbx), better discrimination is needed. To identify clinically significant prostate cancer (CSPC) we determined the performance of LacdiNAc-glycosylated prostate-specific antigen (LDN-PSA) and LDN-PSA normalized by prostate volume (LDN-PSAD). We retrospectively measured LDN-PSA, total PSA (tPSA), and free PSA/tPSA (F/T PSA) values in 718 men who underwent a Pbx in 3 academic urology clinics in Japan and Canada (Pbx cohort) and in 174 PC patients who subsequently underwent radical prostatectomy in Australia (preop-PSA cohort). The assays were evaluated using the area under the receiver operating characteristics curve (AUC) and decision curve analyses to discriminate CSPC. In the Pbx cohort, LDN-PSAD (AUC 0.860) provided significantly better clinical performance for discriminating CSPC compared with LDN-PSA (AUC 0.827, P = 0.0024), PSAD (AUC 0.809, P < 0.0001), tPSA (AUC 0.712, P < 0.0001), and F/T PSA (AUC 0.661, P < 0.0001). The decision curve analysis showed that using a risk threshold of 20% and adding LDN-PSA and LDN-PSAD to the base model (age, digital rectal examination status, tPSA, and F/T PSA) permitted avoidance of even more biopsies without missing CSPC (9.89% and 18.11%, respectively vs 2.23% [base model]). In the preop-PSA cohort, LDN-PSA values positively correlated with tumor volume and tPSA and were significantly higher in pT3, pathological Gleason score ≥ 7. Limitations include limited sample size, retrospective nature, and no family history information prior to biopsy. LacdiNAc-glycosylated PSA is significantly better than the conventional PSA test in identifying patients with CSPC. This study was approved by the ethics committee of each institution ("The Study about Carbohydrate Structure Change in Urological Disease"; approval no. 2014-195).

Thromboembolism in Patients with Bladder Cancer: Incidence, Risk Factors and Prevention.

Patients with bladder cancer are at high risk of developing both venous and arterial thromboembolic events. Factors that contribute to this phenomenon include the hypercoagulable state induced by the malignancy itself, medical comorbidities that are common in this predominantly elderly patient population as well as treatments such as prolonged pelvic surgery and cisplatin-based chemotherapy. While formal guidelines address prevention of venous thromboembolism in patients undergoing radical cystectomy, consensus regarding the role of pharmacologic prophylaxis in patients with bladder cancer being treated with chemotherapy, either with neoadjuvant or adjuvant intent in conjunction with radical cystectomy, as part of bladder preservation protocols or for metastatic disease, has proved elusive. The present narrative review was undertaken to define the incidence of and identify risk factors for thromboembolism among patients with bladder cancer, as well as to assess the efficacy of pharmacologic prophylaxis in reducing the risk of thromboembolism in this patient population.

Endoplasmic reticulum protein ERp46 in prostate adenocarcinoma.

Endoplasmic reticulum (ER) protein ERp46 is a member of the protein disulfide isomerase family of oxidoreductases, which facilitates the reduction of disulfides in proteins and their folding. Accumulation of misfolded proteins has been implicated in cancer. The objectives of the present study were to investigate the role of ERp46 in prostate cancer, its expression and its effects on prostate cancer growth. A tissue microarray with human prostate cancer and normal prostate tissue samples was stained for ERp46 followed by image analysis. Human prostate adenocarcinoma 22Rv1 cells were stably transfected with short hairpin RNA (shRNA) specific for ERp46, a non-effective scrambled control or a plasmid containing full-length human ERp46 cDNA, and cell growth was determined. Subcloned cells were treated with thapsigargin or tunicamycin to induce ER stress and lysates were subjected to western blot analysis for ER stress proteins. Subcutaneous xenografts of parental 22Rv1, ERp46-overexpressing (ERp46+), shERp46 or scrambled control cells were established in male inbred BALB/c nude mice (n=10/group). Tumor growth curves of the xenografts were constructed over a period of 30 days and subsequently the mice were sacrificed and the amount of serum prostate-specific antigen was determined. The results demonstrated increased ERp46 expression levels in prostate cancer tissue samples of Gleason ≥7 compared with normal prostate tissue samples. When ERp46 was stably knocked down using shRNA or overexpressed in prostate carcinoma 22Rv1 cells, tumor growth in vitro and in BALB/c nude mice was inhibited and accelerated, respectively. ERp46 overexpression led to reduced sensitivity to ER stress as indicated by higher half maximal inhibitory concentrations for tunicamycin and thapsigargin in ERp46+ cells. The shERp46 cells lost the ability to upregulate protein disulfide isomerase following tunicamycin-induced ER stress. The present study suggests a role for ERp46 as a therapeutic target in prostate cancer, given its expression profile in human prostate cancer, and its effect on prostate cancer cell growth.

An Automated Micro-Total Immunoassay System for Measuring Cancer-Associated α2,3-linked Sialyl N-Glycan-Carrying Prostate-Specific Antigen May Improve the Accuracy of Prostate Cancer Diagnosis.

The low specificity of the prostate-specific antigen (PSA) for early detection of prostate cancer (PCa) is a major issue worldwide. The aim of this study to examine whether the serum PCa-associated α2,3-linked sialyl N-glycan-carrying PSA (S2,3PSA) ratio measured by automated micro-total immunoassay systems (µTAS system) can be applied as a diagnostic marker of PCa. The µTAS system can utilize affinity-based separation involving noncovalent interaction between the immunocomplex of S2,3PSA and Maackia amurensis lectin to simultaneously determine concentrations of free PSA and S2,3PSA. To validate quantitative performance, both recombinant S2,3PSA and benign-associated α2,6-linked sialyl N-glycan-carrying PSA (S2,6PSA) purified from culture supernatant of PSA cDNA transiently-transfected Chinese hamster ovary (CHO)-K1 cells were used as standard protein. Between 2007 and 2016, fifty patients with biopsy-proven PCa were pair-matched for age and PSA levels, with the same number of benign prostatic hyperplasia (BPH) patients used to validate the diagnostic performance of serum S2,3PSA ratio. A recombinant S2,3PSA- and S2,6PSA-spiked sample was clearly discriminated by µTAS system. Limit of detection of S2,3PSA was 0.05 ng/mL and coefficient variation was less than 3.1%. The area under the curve (AUC) for detection of PCa for the S2,3PSA ratio (%S2,3PSA) with cutoff value 43.85% (AUC; 0.8340) was much superior to total PSA (AUC; 0.5062) using validation sample set. Although the present results are preliminary, the newly developed µTAS platform for measuring %S2,3PSA can achieve the required assay performance specifications for use in the practical and clinical setting and may improve the accuracy of PCa diagnosis. Additional validation studies are warranted.

Elevated C-Peptides, Abdominal Obesity, and Abnormal Adipokine Profile are Associated With Higher Gleason Scores in Prostate Cancer.

BACKGROUND: Prostate cancer development is associated with numerous lifestyle factors (i.e., physical activity, nutrition intake) and metabolic perturbations. These factors have been studied independently; here, we used an integrative approach to characterize these lifestyle and metabolic parameters in men undergoing diagnostic prostate biopsies. METHODS: We prospectively evaluated 51 consecutive men for body composition, metabolic factors including glucose- and lipid-related measures, as well as lifestyle factors prior to prostate biopsy. Evaluations were performed in a blinded manner and were subsequently related to biopsy outcomes for: (i) presence or absence of cancer; and (ii) where cancer was present, Gleason score. RESULTS: Serum C-peptide concentrations were significantly greater in participants with Gleason scores ≥4 + 3 (2.8 ± 1.1 ng/ml) compared to those with Gleason 3 + 3 (1.4 ± 0.6 ng/ml) or Gleason 3 + 4 (1.3 ± 0.8 ng/ml, P = 0.002), suggesting greater insulin secretion despite lack of differences in fasting glucose concentrations. Central adiposity, measured by waist circumference, was significantly greater in participants with Gleason ≥4 + 3 (110.1 ± 7.4 cm) compared to those with Gleason 3 + 4 (102.0 ± 9.5 cm, P = 0.028). Men with Gleason ≥4 + 3 also had significantly greater leptin concentrations than those with lower Gleason scores (Gleason ≥4 + 3: 15.6 ± 3.3 ng/ml vs. Gleason 3 + 4: 8.1 ± 8.1 ng/ml, P < 0.05) and leptin:adiponectin ratio (Gleason ≥4 + 3: 9.7 ± 6.1 AU, Gleason 3 + 4: 2.9 ± 3.2, Gleason 3 + 3: 2.4 ± 2.1 AU, P = 0.013). CONCLUSIONS: We profiled a cluster of obesity-related metabolic perturbations (C-peptide, central adiposity, leptin, and leptin:adiponectin ratios) which may associate with more aggressive prostate cancer histology. Prostate 77:211-221, 2017. © 2016 Wiley Periodicals, Inc.

Incidence, Characteristics and Implications of Thromboembolic Events in Patients with Muscle Invasive Urothelial Carcinoma of the Bladder Undergoing Neoadjuvant Chemotherapy.

PURPOSE: Neoadjuvant chemotherapy and pelvic surgery are significant risk factors for thromboembolic events. Our study objectives were to investigate the timing, incidence and characteristics of thromboembolic events during and after neoadjuvant chemotherapy and subsequent radical cystectomy in patients with muscle invasive bladder cancer. MATERIALS AND METHODS: We performed a multi-institutional retrospective analysis of 761 patients who underwent neoadjuvant chemotherapy and radical cystectomy for muscle invasive bladder cancer from 2002 to 2014. Median followup from diagnosis was 21.4 months (range 3 to 272). Patient characteristics included the Khorana score, and the incidence and timing of thromboembolic events (before vs after radical cystectomy). Survival was calculated using the Kaplan-Meier method. The log rank test and multivariable Cox proportional hazards regression were used to compare survival between patients with vs without thromboembolic events. RESULTS: The Khorana score indicated an intermediate thromboembolic event risk in 88% of patients. The overall incidence of thromboembolic events in patients undergoing neoadjuvant chemotherapy was 14% with a wide variation of 5% to 32% among institutions. Patients with thromboembolic events were older (67.6 vs 64.6 years, p = 0.02) and received a longer neoadjuvant chemotherapy course (10.9 vs 9.7 weeks, p = 0.01) compared to patients without a thromboembolic event. Of the thromboembolic events 58% developed preoperatively and 72% were symptomatic. On multivariable regression analysis the development of a thromboembolic event was not significantly associated with decreased overall survival. However, pathological stage and a high Khorana score were adverse risk factors for overall survival. CONCLUSIONS: Thromboembolic events are common in patients with muscle invasive bladder cancer who undergo neoadjuvant chemotherapy before and after radical cystectomy. Our results suggest that a prospective trial of thromboembolic event prophylaxis during neoadjuvant chemotherapy is warranted.

Androgen deprivation therapy and cardiovascular disease: what is the linking mechanism?

The past decade has brought increased awareness of the potential adverse effects of androgen deprivation therapy (ADT) in men with prostate cancer. Arguably the most important and controversial of these is the increased risk of cardiovascular morbidity and mortality. Although multiple observational studies have shown that men treated with ADT are at increased risk of developing atherosclerotic cardiovascular disease, our understanding of the biological mechanisms that might underlie this phenomenon is still evolving. In this review, we discuss some of the mechanisms that have been proposed to date, including ADT-induced metabolic changes that promote the development and progression of atherosclerotic plaques as well as direct local effects of hormonal factors on plaque growth, rupture and thrombosis.

Inhibition of carbonic anhydrase IX (CA9) sensitizes renal cell carcinoma to ionizing radiation.

While normal kidneys are relatively sensitive to ionizing radiation (IR), renal cell carcinoma (RCC) is considered radioresistant. Carbonic anhydrase IX (CA9), an enzyme that maintains intracellular pH by carbon dioxide dissolution, is upregulated in the majority of RCC, but not in normal kidneys. Since regulation of intracellular pH may enhance radiation effects, we hypothesized that inhibition of CA9 may radiosensitize RCC. Clonogenic survival assay of human clear cell RCC 786-O and murine RCC RAG cells in the presence of a pharmacological CA9 inhibitor or with shRNA-mediated knockdown of CA9 was performed to investigate the response to IR in vitro (single dose or fractionated) and in vivo. Extracellular pH changes were measured in vitro. Treatment with AEBS [4-(2-aminoethyl)benzene sulfonamide], a sulfonamide, was used as a pharmacological inhibitor of the enzymatic activity of CA9. Nude mice bearing subcutaneous xenografts of 786-O cells stably expressing CA9 shRNA or scrambled control were irradiated (6 Gy). Tumor growth was followed longitudinally in the 786-O-bearing mice receiving AEBS (50-200 µg/ml drinking water) or control (vehicle only) which were irradiated (6 Gy) and compared with mice receiving either IR or AEBS alone. In vitro inhibition of CA9 activity or expression significantly sensitized RCC cells to the effects of IR (p<0.05), an effect even more significant when hypofractionated IR was applied. In vivo irradiated xenografts from RCC cells transfected with CA9 shRNA were significantly smaller compared to irradiated xenografts from the scrambled shRNA controls (p<0.05). RCC xenografts from mice treated with AEBS in combination with IR grew significantly slower than all controls (p<0.05). Inhibition of CA9 expression or activity resulted in radiation sensitization of RCC in a preclinical mouse model.

Cardiovascular risk with androgen deprivation therapy for prostate cancer: potential mechanisms.

Androgen deprivation therapy (ADT) is frequently used for the treatment of advanced prostate cancer. ADT is associated with numerous side effects related to its mode of action, namely the suppression of testosterone to castrate levels. Recently, several large retrospective studies have also reported an increased risk of diabetes and cardiovascular disease in men receiving ADT, although these risks have not been confirmed by prospective randomized trials. We review the literature to consider the risk of cardiovascular disease with different forms of ADT and examine in detail potential mechanisms by which any such risk could be mediated. Mechanisms discussed include the metabolic syndrome resulting from low testosterone level and the potential roles of testosterone flare, gonadotropin-releasing hormone receptors outside the pituitary gland, and altered levels of follicle-stimulating hormone. Finally, the clinical implications for men prescribed ADT for the treatment of advanced prostate cancer are considered.

GnRH antagonist associates with less adiposity and reduced characteristics of metabolic syndrome and atherosclerosis compared with orchiectomy and GnRH agonist in a preclinical mouse model.

OBJECTIVES: Observational studies relate androgen deprivation therapy (ADT) to metabolic syndrome (MS) and cardiovascular disease, an association potentially subject to uncontrollable confounding factors, especially diet and genetic/metabolic risk factors. In the absence of prospective randomized clinical trials, causality remains unproven. We comparatively investigated the effects of different ADT modalities on the development of MS and atherosclerosis in a mouse model. MATERIALS AND METHODS: Low-density lipoprotein receptor knockout mice underwent orchiectomy plus vehicle (2.5% mannitol), sham surgery plus vehicle (control), sham surgery plus gonadotropin-releasing hormone (GnRH) antagonist (degarelix), or sham surgery plus GnRH agonist (leuprolide) (n = 9-13/group) and were followed for 4 months. Visceral fat accumulation, lean body mass, adipocyte size, fasting blood glucose, glucose tolerance, serum levels of leptin, follicle-stimulating hormone, luteinizing hormone, and testosterone, along with atherosclerotic plaque size and characteristics were measured. RESULTS: All 3 modes of ADT decreased circulating testosterone levels in mice, although leuprolide treatment reached nadir levels of testosterone later. Orchiectomized and leuprolide-treated mice gained significantly more visceral fat compared with degarelix-treated mice. Improved glucose tolerance tests were recorded in degarelix-treated mice. The aortic atherosclerotic plaque area in leuprolide-treated and orchiectomized mice was larger than in control mice (P<0.005 and P = 0.002, respectively), but it was not significantly different from control in degarelix-treated mice. The necrotic core area in degarelix-treated mice was smaller compared with leuprolide-treated and orchiectomized mice (P = 0.011 and P = 0.002, respectively). CONCLUSIONS: Our results suggest that ADT induced MS and atherosclerosis in a preclinical mouse model to a mode-specific extent. GnRH antagonist generated the least atherosclerosis and characteristics of MS compared with orchiectomy and GnRH agonist.

Endoplasmic reticulum protein ERp46 in renal cell carcinoma.

An established inverse clinical correlation between serum adiponectin levels and renal cell carcinoma (RCC) aggressiveness exists. We have recently demonstrated that adiponectin suppresses clear cell RCC (ccRCC) progression through interaction with its receptor, adiponectin receptor 1 (AdipoR1). ERp46 has been shown to inhibit adiponectin signaling via interaction with AdipoR1 in HeLa cells. However, the expression of ERp46 in RCC has not been described thus far. The objectives of this study were to investigate ERp46 in RCC, its expression, its effects on RCC growth in a mouse model and whether it interacts with AdipoR1. We demonstrated a higher ERp46/AdipoR1 expression ratio in metastatic compared to non-metastatic ccRCC, as determined by immunohistochemistry of tissue microarrays and subsequent image analysis. When ERp46 was stably knocked down using shRNA or overexpressed in murine RCC RAG cells, RCC growth after subcutaneous injection in BALB/c nude mice was inhibited and accelerated, respectively. In vitro analysis to determine the molecular interaction between AdipoR1 and ERp46 included co-immunoprecipitation using human ccRCC 786-O cells and a bacterial adenylate cyclase-based two hybrid system and demonstrated no sustained AdipoR1-ERp46 interaction. This is the first report to suggest a role for ERp46 as a potential therapeutic target in RCC given its expression profile in human RCC samples and its effect on in vivo RCC growth. Since a stable interaction with AdipoR1 could not be established, we suggest that the tumorigenic properties of ERp46 in RCC cells are not related to an inhibitory modulation of AdipoR1.