Increased Expression of Androgen Receptor mRNA in Human Renal Cell Carcinoma Cells is Associated with Poor Prognosis in Patients with Localized Renal Cell Carcinoma

The influence of sex hormones on renal cell carcinoma

Kidney cancer is a common malignancy that constitutes around 5% of all cancer cases. Males are twice as likely to acquire renal cell carcinoma (RCC) compared to females and experience a higher rate of mortality. These disparities indicate that sex hormone (SH)-dependent pathways may have an impact on the aetiology and pathophysiology of RCC. Examination of SH involvement in conventional signalling pathways, as well as genetics and genomics, especially the involvement of ribonucleic acid, reveal further insights into sex-related differences. An understanding of SHs and their influence on kidney cancer is essential to offer patients individualized medicine that would better meet their needs in terms of prevention, diagnosis and treatment. This review presents the understanding of sex-related differences in the clinical manifestation of kidney cancer patients and the underlying biological processes.

Lead Decreases Bone Morphogenetic Protein-7 (BMP-7) Expression and Increases Renal Cell Carcinoma Growth in a Sex-Divergent Manner

Both tissue and blood lead levels are elevated in renal cell carcinoma (RCC) patients. These studies assessed the impact of the subchronic lead challenge on the progression of RCC in vitro and in vivo. Lead challenge of Renca cells with 0.5 μM lead acetate for 10 consecutive passages decreased E-cadherin expression and cell aggregation. Proliferation, colony formation, and wound healing were increased. When lead-challenged cells were injected into mice, tumor size at day 21 was increased; interestingly, this increase was seen in male but not female mice. When mice were challenged with 32 ppm lead in drinking water for 20 weeks prior to tumor cell injection, there was an increase in tumor size in male, but not female, mice at day 21. To investigate the mechanism underlying the sex differences, the expression of sex hormone receptors in Renca cells was examined. Control Renca cells expressed estrogen receptor (ER) alpha but not ER beta or androgen receptor (AR), as assessed by qPCR, and the expression of ERα was increased in tumors in both sexes. In tumor samples harvested from lead-challenged cells, both ERα and AR were detected by qPCR, yet there was a significant decrease in AR seen in lead-challenged tumor cells from male mice only. This was paralleled by a plate-based array demonstrating the same sex difference in BMP-7 gene expression, which was also significantly decreased in tumors harvested from male but not female mice; this finding was validated by immunohistochemistry. A similar expression pattern was seen in tumors harvested from the mice challenged with lead in the drinking water. These data suggest that lead promotes RCC progression in a sex-dependent via a mechanism that may involve sex-divergent changes in BMP-7 expression.

Androgen receptor activity inversely correlates with immune cell infiltration and immunotherapy response across multiple cancer lineages

There is now increasing recognition of the important role of androgen receptor (AR) in modulating immune function. To gain a comprehensive understanding of the effects of AR activity on cancer immunity, we employed a computational approach to profile AR activity in 33 human tumor types using RNA-Seq datasets from The Cancer Genome Atlas. Our pan-cancer analysis revealed that the genes most negatively correlated with AR activity across cancers are involved in active immune system processes. Importantly, we observed a significant negative correlation between AR activity and IFNγ pathway activity at the pan-cancer level. Indeed, using a matched biopsy dataset from subjects with prostate cancer before and after AR-targeted treatment, we verified that inhibiting AR enriches immune cell abundances and is associated with higher IFNγ pathway activity. Furthermore, by analyzing immunotherapy datasets in multiple cancers, our results demonstrate that low AR activity was significantly associated with a favorable response to immunotherapy. Together, our data provide a comprehensive assessment of the relationship between AR signaling and tumor immunity.

Beyond Prostate Cancer: An Androgen Receptor Splice Variant Expression in Multiple Malignancies, Non-Cancer Pathologies, and Development

Multiple studies have demonstrated the importance of androgen receptor (AR) splice variants (SVs) in the progression of prostate cancer to the castration-resistant phenotype and their utility as a diagnostic. However, studies on AR expression in non-prostatic malignancies uncovered that AR-SVs are expressed in glioblastoma, breast, salivary, bladder, kidney, and liver cancers, where they have diverse roles in tumorigenesis. AR-SVs also have roles in non-cancer pathologies. In granulosa cells from women with polycystic ovarian syndrome, unique AR-SVs lead to an increase in androgen production. In patients with nonobstructive azoospermia, testicular Sertoli cells exhibit differential expression of AR-SVs, which is associated with impaired spermatogenesis. Moreover, AR-SVs have been identified in normal cells, including blood mononuclear cells, neuronal lipid rafts, and the placenta. The detection and characterization of AR-SVs in mammalian and non-mammalian species argue that AR-SV expression is evolutionarily conserved and that AR-SV-dependent signaling is a fundamental regulatory feature in multiple cellular contexts. These discoveries argue that alternative splicing of the AR transcript is a commonly used mechanism that leads to an expansion in the repertoire of signaling molecules needed in certain tissues. Various malignancies appropriate this mechanism of alternative AR splicing to acquire a proliferative and survival advantage.

Analysis and Prediction of the Survival Trends of Patients with Clear-Cell Renal Cell Carcinoma: A Model-Based Period Analysis, 2001-2015

Background

Clear-cell renal cell carcinoma (ccRCC) is one of the most common malignant tumors worldwide whose poor prognosis results in a serious disease burden on patients. The changing trend of the long-term relative survival rates (RSRs) of patients with ccRCC was analyzed in this study to evaluate their treatment results over a 15-year period.

Methods

This study is a retrospective study, which assessed and predicted the 1-, 3-, and 5-year survival rates of patients with ccRCC during 2001-2005, 2006-2010, 2011-2015, and 2016-2020 using data extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Period analysis was used in this study to analyze the data from the SEER database and to assess survival differences according to age, sex, race, and socioeconomic status (SES) during the 15-year study period by comparing Kaplan-Meier curves.

Results

During 2001-2015, the 5-year RSR of patients with ccRCC increased from 78.4% to 83.0%, and the generalized linear model predicted that the 5-year RSR increased to 85.7% during 2016-2020. The RSR of patients with ccRCC differed significantly with SES, race, sex, and age. Compared with male patients, the survival advantage of female patients decreased as their age increased. The RSR of all patients with ccRCC was also lower in patients with a lower SES and of black race.

Conclusion

This study found an improvement in the RSR of patients with ccRCC during 2001-2020. Understanding the change trend of the survival rate of patients with ccRCC is helpful to improve the design of clinical trials. It also provides basic data and a scientific basis for evaluating the harm of ccRCC on the health of affected patients and the effect of cancer prevention, and developing cancer prevention plans.

Sex and Gender Differences in Kidney Cancer: Clinical and Experimental Evidence

Simple Summary

Kidney cancer is a frequent malignant tumor that accounts for approximately 5% of all cancer incidences. It affects both males and females, but males are twice as likely to develop kidney cancer than females. Evidence shows that this discrepancy takes root in individual differences, such as genetics or pathologies that affect the patient. It is then reflected in the clinical characteristics of the tumors, as males have larger and more aggressive tumors. Understanding the sex- and gender-based differences in kidney cancer is essential to be able to offer patients individualized medicine that would better cover their needs in terms of prevention, diagnosis and treatment.

Abstract

Sex and gender disparities have been reported for different types of non-reproductive cancers. Males are two times more likely to develop kidney cancer than females and have a higher death rate. These differences can be explained by looking at genetics and genomics, as well as other risk factors such as hypertension and obesity, lifestyle, and female sex hormones. Examination of the hormonal signaling pathways bring further insights into sex-related differences. Sex and gender-based disparities can be observed at the diagnostic, histological and treatment levels, leading to significant outcome difference. This review summarizes the current knowledge about sex and gender-related differences in the clinical presentation of patients with kidney cancer and the possible biological mechanisms that could explain these observations. Underlying sex-based differences may contribute to the development of sex-specific prognostic and diagnostic tools and the improvement of personalized therapies.

Androgen Receptor, Although Not a Specific Marker For, Is a Novel Target to Suppress Glioma Stem Cells as a Therapeutic Strategy for Glioblastoma

Targeting androgen receptor (AR) has been shown to be promising in treating glioblastoma (GBM) in cell culture and flank implant models but the mechanisms remain unclear. AR antagonists including enzalutamide are available for treating prostate cancer patients in clinic and can pass the blood-brain barrier, thus are potentially good candidates for GBM treatment but have not been tested in GBM orthotopically. Our current studies confirmed that in patients, a majority of GBM tumors overexpress AR in both genders. Enzalutamide inhibited the proliferation of GBM cells both in vitro and in vivo. Although confocal microscopy demonstrated that AR is expressed but not specifically in glioma cancer stem cells (CSCs) (CD133+), enzalutamide treatment significantly decreased CSC population in cultured monolayer cells and spheroids, suppressed tumor sphere-forming capacity of GBM cells, and downregulated CSC gene expression at mRNA and protein levels in a dose- and time-dependent manner. We have, for the first time, demonstrated that enzalutamide treatment decreased the density of CSCs in vivo and improved survival in an orthotopic GBM mouse model. We conclude that AR antagonists potently target glioma CSCs in addition to suppressing the overall proliferation of GBM cells as a mechanism supporting their repurposing for clinical applications treating GBM.

BART Cancer: a web resource for transcriptional regulators in cancer genomes

Dysregulation of gene expression plays an important role in cancer development. Identifying transcriptional regulators, including transcription factors and chromatin regulators, that drive the oncogenic gene expression program is a critical task in cancer research. Genomic profiles of active transcriptional regulators from primary cancer samples are limited in the public domain. Here we present BART Cancer (bartcancer.org), an interactive web resource database to display the putative transcriptional regulators that are responsible for differentially regulated genes in 15 different cancer types in The Cancer Genome Atlas (TCGA). BART Cancer integrates over 10000 gene expression profiling RNA-seq datasets from TCGA with over 7000 ChIP-seq datasets from the Cistrome Data Browser database and the Gene Expression Omnibus (GEO). BART Cancer uses Binding Analysis for Regulation of Transcription (BART) for predicting the transcriptional regulators from the differentially expressed genes in cancer samples compared to normal samples. BART Cancer also displays the activities of over 900 transcriptional regulators across cancer types, by integrating computational prediction results from BART and the Cistrome Cancer database. Focusing on transcriptional regulator activities in human cancers, BART Cancer can provide unique insights into epigenetics and transcriptional regulation in cancer, and is a useful data resource for genomics and cancer research communities.

The Association of Androgen Receptor Expression with Renal Cell Carcinoma Risk: a Systematic Review and Meta-Analysis

The relationship between androgen receptor expression and renal cell carcinoma risk remains controversial. This study is aimed to investigate the clinical significance of androgen receptor expression in renal cell carcinoma. A computerized bibliographic search of Embase, the PubMed, and Web of Science combined with manual research between 1977 and 2017 was conducted to explore the association between androgen receptor expression and clinicopathological features of renal cell carcinoma. Data were analyzed by a meta-analysis using RevMan 5.3 analysis software. Eleven retrospective studies with 1839 renal cell carcinoma cases were finally included according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. It was found that there was no significant difference between androgen receptor expression and susceptibility, pathological type, metastatic status, metastatic type (lymph or distant metastasis) and cancer-specific survival of renal cell carcinoma (P > 0.05). However, positive androgen receptor expression was demonstrated to be significantly associated with male patients, lower pathological grade, and earlier tumor stage of renal cell carcinoma (OR = 1.69, 95% CI = 1.30-2.19, P < 0.0001; OR = 2.06, 95% CI = 1.49-2.85, P < 0.0001; OR = 2.81, 95% CI = 1.30-6.12, P = 0.009; respectively). In conclusion, higher androgen receptor expression was correlated with male patients, low tumor grade and early stage of renal cell carcinoma. Based on current results, androgen receptor-inhibited target therapy for renal cell carcinoma patients may be of limited benefits and should be taken into more evaluations.

A magic drug target: Androgen receptor

Androgen receptor (AR) is closely associated with a group of hormone-related diseases including the cancers of prostate, breast, ovary, pancreas, etc and anabolic deficiencies such as muscle atrophy and osteoporosis. Depending on the specific type and stage of the diseases, AR ligands including not only antagonists but also agonists and modulators are considered as potential therapeutics, which makes AR an extremely interesting drug target. Here, we at first review the current understandings on the structural characteristics of AR, and then address why and how AR is investigated as a drug target for the relevant diseases and summarize the representative antagonists and agonists targeting five prospective small molecule binding sites at AR, including ligand-binding pocket, activation function-2 site, binding function-3 site, DNA-binding domain, and N-terminal domain, providing recent insights from a target and drug development view. Further comprehensive studies on AR and AR ligands would bring fruitful information and push the therapy of AR relevant diseases forward.

Hormonal manipulation with finasteride or oral contraception does not influence incidence of renal cell carcinoma

Androgens have been suspected to be involved in the initiation of renal cell carcinoma because of a two-fold increased risk in men compared with women. To investigate the role of self-reported finasteride or oral contraceptive use in the Prostate, Lung, Colorectal, and Ovarian (PCLO) to determine whether the androgen receptor reduces renal cancer development. We query the PCLO trial for predictor variables from the baseline questionnaire and follow-up questionnaires enquiring medication use, specifically the use of 5-α reductase inhibitors (dutasteride or finasteride) and oral contraceptive therapy. The primary outcome of this study was the incidence of renal cancer. Statistical analysis included Student's t-test for continuous variables, χ, or Fisher's exact tests for dichotomous or categorical variables, and multivariable analysis using Cox proportional hazards models. Eight percent (n=6117/73 694) of men in the PCLO trial reported the use of finasteride. 52 (10.6%) of the 492 men diagnosed with renal cancer had self-reported exposure to finasteride and this was not significant in univariable analysis (52/6169; 0.84% vs. 440/66 454; 0.67%, P=0.12) or multivariable main effects analysis (hazard ratio: 1.12; 95% confidence interval: 0.83-1.5; P=0.47). Approximately 54% of women (n=40 997/75 989) in the PCLO trial reported the use of oral contraceptives by questionnaire. 136 (52.1%) of the 261 women diagnosed with renal cancer had self-reported exposure to oral contraceptive therapy and this was not significant in univariable analysis (136/40 997; 0.33% vs. 125/34 992; 0.36%, P=0.36) or in multivariable main effects analysis (hazard ratio: 1.03; 95% confidence interval: 0.97-1.1; P=0.30). Self-reported use of finasteride or oral contraceptives is not associated with a reduced incidence of renal cancer.

Role of the androgen signaling axis in genitourinary malignancies

As we learn more about the molecular biology of genitourinary malignancies, novel therapeutic strategies can be developed. This is especially crucial for prostate, renal, and bladder cancer, where mortality rates remain high especially in advanced disease states. The androgen signaling axis and the androgen receptor (AR) are areas that are actively being explored for their role in these diseases. Although long been associated with prostate cancer development and progression, the role of AR in renal cell carcinoma (RCC) and bladder cancer is becoming recognized as well. This review will highlight the current research into the role of the androgen signaling axis in genitourinary malignancies and how this pathway is being used to expand our therapeutic armamentarium.

Prognostic relevance of androgen receptor expression in renal cell carcinomas

Background

Despite rapid discoveries in molecular biology of renal cell carcinoma (RCC) and advances in systemic targeted therapies, development of new diagnostic and therapeutic strategies is urgently needed. The androgen receptor (AR) has been shown to hold prognostic and predicitve value in several malignancies. Here, we studied a possible association between AR expression and prognosis in patients with RCCs.

Results

Low AR expression levels were associated with occurrence of distant metastasis and higher tumor stage in papillary and clear-cell RCCs. Importantly, multivariate Cox regression analyses revealed that AR is an independent prognostic factor for cancer-specific survival.

Materials and Methods

The expression of AR was measured by immunohistochemistry and assessed by digital image analysis using a tissue microarray containing tumor tissue of a large and well-documented series of RCC patients with long-term follow-up information. Chi-squared tests, Kaplan-Meier curves and Cox regression models were used to investigate the possible relationship between AR expression and clinico-pathological characteristics and patient survival.

Conclusions

Patients affected by AR-positive tumors exhibit a favorable prognosis by multiple Cox regression, while loss of AR expression is related to aggressive disease. Therefore, assessing AR expression offers valuable prognostic information that could improve treatment selection for metastatic disease. Moreover, our findings highlight a potential therapeutic use of AR pharmaceuticals in patients with RCCs.

Impact of preoperative thrombocytosis on prognosis after surgical treatment in pathological T1 and T2 renal cell carcinoma: results of a multi-institutional comprehensive study

Background

The prognostic significance of preoperative thrombocytosis (TC) in renal cell carcinoma (RCC) is not without some debate. The aim of the present multi-institutional study was to determine the association of preoperative TC with the clinicopathological features and prognosis of localized RCC patients who underwent surgery in a large cohort.

Methods

A study involving 8 institutions, and 4,376 patients with pT1 and pT2 RCC from the Korean renal cell carcinoma (KORCC) database, was conducted. TC was defined as a platelet count ≥400,000/μL. Patients were divided into 2 groups based on the presence of preoperative TC. Clinicopathological variables and survival rates were compared between the 2 groups.

Results

Out of the 4,376 patients in the study, 106 (2.4%) had preoperative TC. Compared to patients without TC, these patients had a lower body mass index. Additionally, these patients had more advanced stage tumors with a higher Fuhrman grade, and higher incidence of symptoms at the time of diagnosis. Kaplan-Meier curves revealed that patients with TC had a significantly lower rate of recurrence-free survival (RFS). Furthermore, a lower rate of overall survival (OS) was exhibited amongst patients with TC. Multivariate analysis revealed that TC was an independent prognostic factor in terms of the RFS and OS.

Conclusions

TC appeared to be an important prognostic determinant in localized RCC. Furthermore, preoperative platelet count may be clinically useful for risk stratification of patients with surgically treated localized RCC.

Intracrine androgen biosynthesis in renal cell carcinoma

BACKGROUND

Renal cell carcinoma (RCC) is one of the most lethal genitourinary cancers. The presence of androgen receptor (AR) in RCC has recently been shown to be associated with higher tumour stage irrespective of gender. Because the clinical context of androgens in female RCC patients is similar to that of prostate cancer patients undergoing androgen-deprivation therapy, mechanisms underlying the emergence of castration-resistant prostate cancer (CRPC) may be at play in AR-positive RCC cells. Therefore, we hypothesized that AR-positive RCC has intratumoral steroidogenesis and that anti-androgen therapy may result in tumour suppression.

METHODS

Mice were injected with an AR-positive RCC cell line. When tumours became palpable, surgical castration was performed and tumour volume was measured. Using ELISA, the levels of intracellular testosterone and dihydrotesterone were measured in AR-positive human RCC cell lines. Lastly, male mice containing xenografts were treated with enzalutamide or abiraterone acetate (AA) for 3 weeks to measure tumour volume.

RESULTS

We first observed in vivo that castration retards the growth of AR-positive RCC tumour xenograft in mice. Next, AR-positive human RCC cell lines and tissues were found to have elevated levels of testosterone and dihydrotestosterone and express key enzymes required for intracellular androgen biosynthesis. A mouse xenograft study with AR-positive RCC cell line using the commonly used anti-androgen therapies showed significant tumour suppression (P<0.01).

CONCLUSIONS

Intracrine androgen biosynthesis is a potential source of androgen in AR-positive RCC and that the androgen signaling axis is a potential target of intervention in RCC.

Reciprocal androgen receptor/interleukin-6 crosstalk drives oesophageal carcinoma progression and contributes to patient prognosis

Oesophageal squamous cell carcinoma (ESCC), a leading lethal malignancy of the digestive tract, is characterized by marked gender disparity. Clarifying the roles of the function and regulatory pathway of the androgen receptor (AR) will improve our understanding of oesophageal cancer progression, thereby facilitating the personalized management of ESCC. Here we report evidence to show that AR is a key mediator of inflammatory signals in ESCC cancer progression. High AR expression was associated with poor overall survival in tobacco-using ESCC patients but not in ESCC patients not using tobacco. A gain and loss of AR function enhanced and repressed ESCC cell growth, respectively, by altering cell cycle progression. In mice bearing human ESCC xenografts, silencing AR expression attenuated tumour growth, whereas AR overexpression promoted tumour growth in mice of different androgen statuses (male, female, and castrated male). Array assays revealed that the inflammatory cytokine interleukin-6 (IL6) is a prominent AR target gene in ESCC. By directly binding to the IL6 promoter, AR enhances IL6 transcription, and IL6 can in turn activate AR expression, thus forming a reciprocal regulatory circuit to sustain STAT3 oncogenic signalling in ESCC. Moreover, high expression levels of both AR and IL6 in human ESCC predict poor clinical outcome in tobacco users. Together, these data establish that AR promotes ESCC growth and is associated with poor patient prognosis. The discovery of a positive feedback loop between IL6 and AR bridges the knowledge gaps among lifestyle factor-associated inflammation, gender disparity, and oesophageal carcinoma. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

C1QBP Regulates YBX1 to Suppress the Androgen Receptor (AR)-Enhanced RCC Cell Invasion

Early studies suggested that the androgen receptor (AR) might play important roles to promote the renal cell carcinoma (RCC) progression; however, the detailed mechanisms remain unclear. Here we demonstrated the higher YBX1 expression with lower C1QBP expression in human RCC clinical tissues, and the intensity of C1QBP was negatively correlated with the YBX1 nuclear expression. Mechanism dissection found C1QBP could interact with YBX1 to suppress the YBX1 activation via altering the YBX1 phosphorylation and nuclear translocation in RCC cells. The consequences of such suppression of YBX1 might then result in suppressing the RCC cell migration and invasion that involved altering the AR-modulated MMP9 signals. Interruption of this newly identified C1QBP→YBX1→AR→MMP9-suppressed RCC cell invasion pathway via targeting YBX1 or AR partially reversed the RCC cell invasion. Importantly, results from in vivo mouse model with orthotopic implantation of RCC OSRC2 cells into the left renal capsule also confirmed in vitro cell line studies showing targeting YBX1 could suppress RCC cell invasion via regulation of AR/MMP9 signals. Collectively, these data suggest that C1QBP could regulate YBX1 to suppress the AR-enhanced RCC cell invasion. Targeting this newly identified C1QBP/YBX1/AR/MMP9 signal pathway may provide a new potential therapy to better suppress RCC metastasis.

AR-Signaling in Human Malignancies: Prostate Cancer and Beyond

In the 1940s Charles Huggins reported remarkable palliative benefits following surgical castration in men with advanced prostate cancer, and since then the androgen receptor (AR) has remained the main therapeutic target in this disease. Over the past couple of decades, our understanding of AR-signaling biology has dramatically improved, and it has become apparent that the AR can modulate a number of other well-described oncogenic signaling pathways. Not surprisingly, mounting preclinical and epidemiologic data now supports a role for AR-signaling in promoting the growth and progression of several cancers other than prostate, and early phase clinical trials have documented preliminary signs of efficacy when AR-signaling inhibitors are used in several of these malignancies. In this article, we provide an overview of the evidence supporting the use of AR-directed therapies in prostate as well as other cancers, with an emphasis on the rationale for targeting AR-signaling across tumor types.

Enzalutamide inhibits proliferation of gemcitabine-resistant bladder cancer cells with increased androgen receptor expression

Advanced bladder cancer is treated mainly with gemcitabine and cisplatin, but most patients eventually become resistance. Androgen receptor (AR) signaling has been implicated in bladder cancer as well as other types of cancer including prostate cancer. In this study, we investigated the expression and role of AR in gemcitabine-resistant bladder cancer cells and also the potential of enzalutamide, an AR inhibitor, as a therapeutic for the chemoresistance. First of all, we established gemcitabine-resistant T24 cells (T24GR) from T24 bladder cancer cells and performed gene expression profiling. Microarray analysis revealed upregulation of AR expression in T24GR cells compared with T24 cells. AR mRNA and protein expression was confirmed to be increased in T24GR cells, respectively, by quantitative RT-PCR and western blot analysis, which was associated with more potent AR transcriptional activity as measured by luciferase reporter assay. The copy number of AR gene in T24GR cells determined by PCR was twice as many as that of T24 cells. AR silencing by siRNA transfection resulted in inhibition of proliferation of T24GR cells. Cell culture in charcoal-stripped serum and treatment with enzalutamide inhibited growth of T24GR cells, which was accompanied by cell cycle arrest. AR transcriptional activity was found to be reduced in T24GR cells by enzalutamide treatment. Lastly, enzalutamide also inhibited cell proliferation of HTB5 bladder cancer cells that express AR and possess intrinsic resistance to gemcitabine. Our results suggest that enzalutamide may have the potential to treat patients with advanced gemcitabine-resistant bladder cancer with increased AR expression.

GFOD1 and peejar are promising markers for clear-cell renal cell carcinoma disease progression

Clear cell renal cell carcinoma (ccRCC) is a common genitourinary malignancy. The molecular pathogenesis of ccRCC remains unclear and biomarkers for daily practice were still limited. We performed an integrative analysis of two public ccRCC microarray datasets, E-GEOD-22541 and E-MTAB-1050, The candidate differential expression genes (DEG) were then confirmed in the E-GEOD-53757 dataset. In addition, an independent cohort of 50 ccRCC and 36 non-tumor kidney tissues were analyzed to examine the selected DGEs by qRT-PCR. We identified and validated two DEGs, namely GFOD1 and peejar, which were significantly up-regulated in ccRCC compared with normal renal tissues (p < 0.001). Moreover, the expression of these two genes are related to histological grade and stage and decrease of their expression correlated with disease progression (p < 0.05). Furthermore, we found the expression of peejar was positively correlated with the expression of GFOD1 in ccRCC tissue, with Pearson correlation coefficiency reaching 0.939 (p < 0.001). GFOD1 and peejar were novel genes correlated with ccRCC disease progression and patients' poor prognosis.

In vitro evidence of the promoting effect of testosterone in kidney stone disease: A proteomics approach and functional validation

Incidence of kidney stone disease in males is 2- to 4-fold greater than in females. This study aimed to determine effects of testosterone on kidney stone disease using a proteomics approach. MDCK renal tubular cells were treated with or without 20nM testosterone for 7days. Cellular proteins were extracted, resolved by 2-DE, and stained with Deep Purple fluorescence dye (n=5 gels derived from 5 independent samples/group). Spot matching, quantitative intensity analysis, and statistics revealed significant changes in levels of nine protein spots after testosterone treatment. These proteins were then identified by nanoLC-ESI-Qq-TOF MS/MS. Global protein network analysis using STRING software revealed α-enolase as the central node of protein-protein interactions. The increased level of α-enolase was then confirmed by Western blotting analysis, whereas immunofluorescence study revealed the increased α-enolase on cell surface and intracellularly. Functional analysis confirmed the potential role of the increased α-enolase in enhanced calcium oxalate monohydrate (COM) crystal-cell adhesion induced by testosterone. Finally, neutralization of surface α-enolase using anti-α-enolase antibody successfully reduced the enhanced COM crystal-cell adhesion to the basal level. Our data provided in vitro evidence of promoting effect of testosterone on kidney stone disease via enhanced COM crystal-cell adhesion by the increased surface α-enolase.

BIOLOGICAL SIGNIFICANCE

The incidence of kidney stone disease in male is 2- to 4-fold greater than in female. One of the possible factors of the male preference is the higher testosterone hormone level. However, precise molecular mechanisms that testosterone plays in kidney stone disease remained unclear. Our present study is the first exploratory investigation on such aspect using a proteomics approach. Our data also provide a novel mechanistic aspect of how testosterone can impact the risk of kidney stone formation (i.e. the discovery that testosterone increases alpha-enolase expression on the surface of renal tubular cells that is responsible, at least in part, for crystal-cell adhesion).

A Protective Role for Androgen Receptor in Clear Cell Renal Cell Carcinoma Based on Mining TCGA Data

Androgen receptor (AR) is expressed in normal murine and human kidneys of both genders, but its physiologic role is uncertain. Several studies showed loss of AR in renal cell carcinoma (RCC) in conjunction with increasing clinical stage and pathological grade, but others found that higher AR expression correlated with worse outcomes. Limited functional studies with renal cell lines suggested tumor-promoting activity of AR. In this study, we queried transcriptomic, proteomic, epigenetic and survival data from The Cancer Genome Atlas (TCGA) to evaluate AR expression and its association with overall survival in three subtypes of RCC (clear cell [ccRCC], papillary [pRCC], and chromophobe [chRCC]). We found that although there was no significant difference in AR mRNA expression in ccRCC of males vs. females, AR protein expression in ccRCC was significantly higher in male compared to female patients. More importantly, higher expression of AR at both transcript and protein levels was associated with improved overall survival in both genders with ccRCC, but did not predict survival of either gender with pRCC or chRCC. Genes whose transcript levels were associated with AR mRNA levels significantly overlapped between ccRCC and pRCC, but not with chRCC, suggesting a similar transcriptional program mediated by AR in ccRCC and pRCC. Ingenuity pathway analysis also identified overlapping pathways and upstream regulators enriched in AR-associated genes in ccRCC and pRCC. Hypermethylation of CpG sites located in the promoter and first exon of AR was associated with loss of AR expression and poor overall survival. Our findings support a tumor suppressor role for AR in both genders that might be exploited to decrease the incidence or progression of ccRCC.

DNA repair system and renal cell carcinoma prognosis: under the influence of NBS1

Nibrin (NBS1) is a protein involved in the maintenance of genomic stability and in DNA repair mechanisms. The NBS1 E185Q polymorphism (rs1805794) has been investigated in several studies, including its influence in the pathogenesis of renal cell carcinoma (RCC), although its prognostic value is still not determined for these patients. The purpose of the present work was to determine the role of NBS1 E185Q polymorphism as a prognostic factor/genetic marker of survival in patients with RCC. We conducted a hospital-based study analyzing 172 caucasian patients with histopathological diagnosis of RCC, for which polymorphism genotyping was performed by TaqMan(®) Allelic Discrimination methodology. In this study, we have found that male patients, non-metastatic at diagnosis and NBS1 C allele carriers (GC/CC) showed a lower 5-years survival when compared with GG genotype patients (P = 0.045). Furthermore, for carriers of low-activity NBS1 C allele, multivariate Cox regression analysis revealed almost a fourfold increase in risk of death at 5 years, after adjustment for age, histological type, Fuhrman's grade, tumor size and vascular permeation (HR 3.92; 95 % CI 1.33-11.57; P = 0.013). There were no statistically significant differences between the NBS1 E185Q genotypes and the assessed patients' clinical-pathological characteristics. Our results demonstrate for the first time the impact of NBS1 E185Q polymorphism in RCC prognosis suggesting that, for RCC male patients non-metastatic at diagnosis, this polymorphism might be a putative genetic marker in the clinical outcome.