Prognostic relevance of androgen receptor expression in renal cell carcinomas

Frequent gene mutations and the correlations with clinicopathological features in clear cell renal cell carcinoma: preliminary study based on Chinese population and TCGA database

BACKGROUND

Large-scale sequencing plays important roles in revealing the genomic map of ccRCC and predicting prognosis and therapeutic response to targeted drugs. However, the relevant clinical data is still sparse in Chinese population.

METHODS

Fresh tumor specimens were collected from 66 Chinese ccRCC patients, then the genomic RNAs were subjected to whole transcriptome sequencing (WTS). We comprehensively analyzed the frequently mutated genes from our hospital's cohort as well as TCGA-KIRC cohort.

RESULTS

VHL gene is the most frequently mutated gene in ccRCC. In our cohort, BAP1 and PTEN are significantly associated with a higher tumor grade and DNM2 is significantly associated with a lower tumor grade. The mutant type (MT) groups of BAP1 or PTEN, BAP1 or SETD2, BAP1 or TP53, BAP1 or MTOR, BAP1 or FAT1 and BAP1 or AR had a significantly correlation with higher tumor grade in our cohort. Moreover, we identified HMCN1 was a hub mutant gene which was closely related to worse prognosis and may enhance anti-tumor immune responses.

CONCLUSIONS

In this preliminary research, we comprehensively analyzed the frequently mutated genes in the Chinese population and TCGA database, which may bring new insights to the diagnosis and medical treatment of ccRCC.

CD15 Is a Risk Predictor and a Novel Target in Clear Cell Renal Cell Carcinoma

INTRODUCTION

Tumor cells use adhesion molecules like CD15 or sialylCD15 (sCD15) for metastatic spreading. We analyzed the expression of CD15 and sCD15 in clear cell renal cell carcinoma (ccRCC) regarding prognosis.

METHODS

A tissue microarray containing tissue specimens of 763 patients with ccRCC was immunohistochemically stained for CD15 and sCD15, their expression quantified using digital image analysis, and the impact on patients' survival analyzed. The cell lines 769p and 786o were stimulated with CD15 or control antibody in vitro and the effects on pathways activating AP-1 and tumor cell migration were examined.

RESULTS

ccRCC showed a broad range of CD15 and sCD15 expression. A high CD15 expression was significantly associated with favorable outcome (p < 0.01) and low-grade tumor differentiation (p < 0.001), whereas sCD15 had no significant prognostic value. Tumors with synchronous distant metastasis had a significantly lower CD15 expression compared to tumors without any (p < 0.001) or with metachronous metastasis (p < 0.01). Tumor cell migration was significantly reduced after CD15 stimulation in vitro, but there were no major effects on the activating pathways of AP-1.

CONCLUSION

CD15, but not sCD15, qualifies as a biomarker for risk stratification and as an interesting novel target in ccRCC. Moreover, the data indicate a contribution of CD15 to metachronous metastasis. Further research is warranted to decipher the intracellular pathways of CD15 signaling in ccRCC in order to characterize the CD15 effects on ccRCC more precisely.

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.

Discovery of pathway-independent protein signatures associated with clinical outcome in human cancer cohorts

Proteomic data provide a direct readout of protein function, thus constituting an information-rich resource for prognostic and predictive modeling. However, protein array data may not fully capture pathway activity due to the limited number of molecules and incomplete pathway coverage compared to other high-throughput technologies. For the present study, our aim was to improve clinical outcome prediction compared to published pathway-dependent prognostic signatures for The Cancer Genome Atlas (TCGA) cohorts using the least absolute shrinkage and selection operator (LASSO). RPPA data is particularly well-suited to the LASSO due to the relatively low number of predictors compared to larger genomic data matrices. Our approach selected predictors regardless of their pathway membership and optimally combined their RPPA measurements into a weighted risk score. Performance was assessed and compared to that of the published signatures using two unbiased approaches: 1) 10 iterations of threefold cross-validation for unbiased estimation of hazard ratio and difference in 5-year survival (by Kaplan-Meier method) between predictor-defined high and low risk groups; and 2) a permutation test to evaluate the statistical significance of the cross-validated log-rank statistic. Here, we demonstrate strong stratification of 445 renal clear cell carcinoma tumors from The Cancer Genome Atlas (TCGA) into high and low risk groups using LASSO regression on RPPA data. Median cross-validated difference in 5-year overall survival was 32.8%, compared to 25.2% using a published receptor tyrosine kinase (RTK) prognostic signature (median hazard ratios of 3.3 and 2.4, respectively). Applicability and performance of our approach was demonstrated in three additional TCGA cohorts: ovarian serous cystadenocarcinoma (OVCA), sarcoma (SARC), and cutaneous melanoma (SKCM). The data-driven LASSO-based approach is versatile and well-suited for discovery of new protein/disease associations.

Differential Expression of the Androgen Receptor, Splice Variants and Relaxin 2 in Renal Cancer

Background: The role of the androgen receptor (AR) in renal cell carcinoma (RCC) is unclear. We aimed to analyze the expression of AR and its splice variants (SVs) and their correlation with relaxin 2 (RLN2) and cytokines in RCC. Methods: We investigated the expression of RLN2 and AR variants in 25 clear cell RCC (ccRCC) and 9 papillary (pRCC) tumor tissues and the corresponding controls using quantitative PCR and serum RLN2, testosterone and cytokine levels in matched samples using ELISA and chemiluminescent immunometric assay, respectively. Results: ccRCC tissues but not pRCC tissues more frequently expressed AR and the SVs than did normal tissues. All pRCC samples expressed more AR than did ccRCC samples. The highest expression of all AR variants except AR-V12 was found in low-stage tumors, with dominant expression of AR-V7. In males in the ccRCC cohort, the expression of AR-FL, AR-V1 and AR-V3 was significantly correlated with that of RLN2. The secretion pattern of proinflammatory IL-6 was higher in ccRCC than in pRCC. Conclusions: The results highlight additional molecular differences between ccRCC and pRCC, suggesting the influence of external factors on the whole kidney or genetic predispositions to developing certain types of renal cancer, and may support further pathological analysis and studies of targeted hormone therapy.

Controlled ovarian stimulation therapy as a potential risk for the development and progression of renal cell carcinomas: A case report and literature review

Renal Cell Carcinoma (RCC) is the most common type of cancer in the kidney and is mostly asymptomatic. Previous studies have supported the important role of sex hormones in RCC pathophysiology and that targeted hormone receptor therapy, such as estrogen receptor targeting, is a promising treatment strategy. However, to the best of our knowledge, it remains unknown whether hormonal therapy, such as controlled ovarian stimulation for in vitro fertilization, serves a role in the development and progression of RCC. The present report describes a case of RCC developed after a fertility stimulation therapy and provides a summary of the known literature on the role of hormone receptors in the development and progression of RCC. A 35-year-old woman received fertility stimulation treatment with follitropin alfa 900 units, human chorionic gonadotropic hormone 5,000 units, injectable leuprolide 1 mg/0.2 ml and cetrotide 0.25 mg. The patient presented to the hospital with shortness of breath and weight loss. The patient had no known genetic predisposition or family history of malignancies and no exposure to chemicals. The patient never used tobacco, alcohol or recreational drugs. Imaging revealed a 17x19 mm, heterogeneously enhancing, and partially exophytic mass in the right kidney. After partial nephrectomy, the pathological evaluation confirmed the diagnosis of clear cell RCC. To the best of our knowledge, this was the first time that a case of ovarian stimulation therapy was associated with the development of RCC. This case raises concerns about the potential oncogenic effect of controlled ovarian stimulation therapy in RCC promotion, suggesting a need for systematic research to clarify the clinical significance of existing pre-clinical data.

Y box binding protein 1 (YB-1) oncoprotein at the hub of DNA proliferation, damage and cancer progression

The Y Box binding protein 1 (YB-1) belongs to the highly conserved Cold Shock Domain protein family and is a major component of messenger ribonucleoprotein particles (mRNPs) in various organisms and cells. Cold Shock proteins are multifunctional nucleic acids binding proteins involved in a variety of cellular functions. Biological activities of YB-1 range from the regulation of transcription, splicing and translation, to the orchestration of exosomal RNA content. The role of YB-1 in malignant cell transformation and fate transition is the subject of intensive investigation. Besides, emerging evidence indicates that YB-1 participates in several DNA damage repair pathways as a non-canonical DNA repair factor thus pointing out that the protein can allow cancer cells to evade conventional anticancer therapies and avoid cell death. Here, we will attempt to collect and summarize the current knowledge on this subject and provide the basis for further lines of inquiry.

Histone Demethylase LSD1 Regulates Kidney Cancer Progression by Modulating Androgen Receptor Activity

Kidney cancer is one of the most difficult cancers to treat by targeted and radiation therapy. Therefore, identifying key regulators in this cancer is especially important for finding new drugs. We focused on androgen receptor (AR) regulation by its epigenetic co-regulator lysine-specific histone demethylase 1 (LSD1) in kidney cancer development. LSD1 knock-down in kidney cancer cells decreased expression of AR target genes. Moreover, the binding of AR to target gene promoters was reduced and histone methylation status was changed in LSD1 knock-down kidney cancer cells. LSD1 knock-down also slowed growth and decreased the migration ability of kidney cancer cells. We found that pargyline, known as a LSD1 inhibitor, can reduce AR activity in kidney cancer cells. The treatment of kidney cancer cells with pargyline delayed growth and repressed epithelial–mesenchymal transition (EMT) markers. These effects were additively enhanced by co-treatment with the AR inhibitor enzalutamide. Down-regulation of LSD1 in renal cancer cells (RCC) attenuated in vivo tumor growth in a xenograft mouse model. These results provide evidence that LSD1 can regulate kidney cancer cell growth via epigenetic control of AR transcription factors and that LSD1 inhibitors may be good candidate drugs for treating kidney cancer.

Novel molecular signatures and potential therapeutics in renal cell carcinomas: Insights from a comparative analysis of subtypes

Renal cell carcinomas (RCCs) are among the highest causes of cancer mortality. Although transcriptome profiling studies in the last decade have made significant molecular findings on RCCs, effective diagnosis and treatment strategies have yet to be achieved due to lack of adequate screening and comparative profiling of RCC subtypes. In this study, a comparative analysis was performed on RNA-seq based transcriptome data from each RCC subtype, namely clear cell RCC (KIRC), papillary RCC (KIRP) and kidney chromophobe (KICH), and mutual or subtype-specific reporter biomolecules were identified at RNA, protein, and metabolite levels by the integration of expression profiles with genome-scale biomolecular networks. This approach revealed already-known biomarkers in RCCs as well as novel biomarker candidates and potential therapeutic targets. Our findings also pointed out the incorporation of the molecular mechanisms of KIRC and KIRP, whereas KICH was shown to have distinct molecular signatures. Furthermore, considering the Dipeptidyl Peptidase 4 (DPP4) receptor as a potential therapeutic target specific to KICH, several drug candidates such as ZINC6745464 were identified through virtual screening of ZINC molecules. In this study, we reported valuable data for further experimental and clinical efforts, since the proposed molecules have significant potential for screening and therapeutic purposes in RCCs.

Prognostic and Predictive Value of Tumor-infiltrating Leukocytes and of Immune Checkpoint Molecules PD1 and PDL1 in Clear Cell Renal Cell Carcinoma

INTRODUCTION: Immune checkpoint inhibitors (ICI) have been approved for patients with clear cell renal cell carcinoma (ccRCC), but not all patients benefit from ICI. One reason is the tumor microenvironment (TME) that has substantial influence on patient's prognosis and therapy response. Thus, we comprehensively analyzed the TME of ccRCC regarding prognostic and predictive properties. METHODS: Tumor-infiltrating CD3-positive T-cells, CD8-positive cytotoxic T-lymphocytes (CTLs), regulatory T-cells, B-cells, plasma cells, macrophages, granulocytes, programmed cell death receptor 1 (PD-1), and its ligand PD-L1 were examined in a large hospital-based series of ccRCC with long-term follow-up information (n = 756) and in another patient collective with information on response to nivolumab therapy (n = 8). Tissue microarray technique and digital image analysis were used. Relationship between immune cell infiltration and tumor characteristics, cancer-specific survival (CSS), or response to ICI was examined. RESULTS: Univariate survival analysis revealed that increased tumor-infiltrating B-cells, T-cells, and PD-1-positive cells were significantly associated with favorable CSS and high levels of intratumoral granulocytes, macrophages, cytotoxic T-cells, and PD-L1 significantly with poor CSS. High CTL or B-cell infiltration and high PD-L1 expression of ccRCC tumor cells qualified as independent prognostic biomarkers for patients' CSS. Significantly higher densities of intratumoral T-cells, CTLs, and PD-1-positive immune cells were observed in ccRCC with response to ICI compared with patients with mixed or no response (CD3: p = 0.003; CD8: p = 0.006; PD-1: p = 0.01). DISCUSSION: This study shows that subsets of tumor-infiltrating leukocytes in the TME and also PD-1/PD-L1 provide prognostic and predictive information for patients with ccRCC.

Lamin-B1 is a senescence-associated biomarker in clear-cell renal cell carcinoma

Clear-cell renal cell carcinoma (ccRCC) is a von-Hippel-Lindau gene (VHL) associated tumor disease. In addition to activating the hypoxia inducible factor (HIF) dependent oxygen-sensing pathway, VHL loss also has an impact on a HIF-independent senescence program which functions as a tumorigenesis barrier. Lamin-B1 is a nuclear intermediate filament protein that exhibits effects on chromatin structure and gene expression and acts as a senescence effector. In the present study, the expression and prognostic relevance of Lamin-B1 in a large cohort of ccRCC patients was examined and the report presents initial functional data on possible therapeutic implications. The expression of Lamin-B1 was measured by immunohistochemistry using a tissue microarray containing tumor tissue samples from 763 ccRCC patients. Chi-squared tests, Kaplan-Meier curves and Cox regression models were used to investigate the possible association between Lamin-B1 expression, clinical and pathological characteristics and patient survival. High Lamin-B1 expression was associated with poor clinical outcomes and multivariate Cox regression analyses revealed that Lamin-B1 was an independent prognostic factor for cancer-specific survival. Furthermore in vitro data suggested that Lamin-B1 acted as a functional downstream senescence effector in RCC cell lines. In conclusion, patients affected by ccRCC with high Lamin-B1 expression exhibit poor prognosis. Lamin-B1 may serve as a tissue-based biomarker for new therapeutic agents targeting therapy-induced senescence.

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.

Biomarkers of aggressiveness in genitourinary tumors with emphasis on kidney, bladder, and prostate cancer

INTRODUCTION

Over the last decade, the improvement in molecular techniques and the acquisition of genomic information has transformed and increased the quality of patient care and our knowledge of diseases. Areas covered: Protein expression levels in immunohistochemistry and molecular biomarkers are reported for their ability to predict recurrence, progression, development of metastases, or patient survival. In particular, for renal cell carcinoma, we take into consideration the biomarkers applicable to immunohistochemistry and with molecular and genetic analyses. In urothelial carcinoma, there is great interest in the possibility of distinguishing the basal vs. luminal subtypes and to acquire deeper insight into the tumor biology through examining exosomes in urine and biomarkers in the serum. In prostate cancer, single gene expression and multiple gene expression classifiers are reviewed as a tool to distinguish indolent vs. aggressive disease. Expert commentary: The genomic information along with the application of ancillary techniques allow the definition of a neoplasia not only by its morphology but also by its biological signature. This continuous increase in knowledge will result in a better comprehension of oncogenesis, development of targeted therapies and optimizing decision-making processes related to patient care.

SPOP, ZEB-1 and E-cadherin expression in clear cell renal cell carcinoma (cc-RCC): Clinicopathological and prognostic significance

BACKGROUND

Clear cell renal cell carcinoma (cc-RCC), is a serious cancer regarding; its fatality, liability for metastases and chemoresistance, so identification of recent therapeutic targets to improve the patients prognosis is needed. SPOP is a BTB/POZ domain containing speckle-type POZ protein, has been identified as an E3 ubiquitin ligase component. ZEB1 is an essential epithelial mesenchymal transition (EMT) activator; E-cadherin is a cell adhesion protein that had been detected in normal epithelial cells membrane.

AIM

Was to assess the tissue protein markers SPOP, ZEB1 & E-cadherin expressions in benign areas of neoplastic kidney specimens and in cc-RCC patients, then correlating their expression levels with patients clinicopathological and prognostic data.

METHODS

We evaluated SPOP, ZEB-1 & E-cadherin expression using immunohistochemistry in samples from 50 cc-RCC and 20 benign areas of neoplastic kidney specimens, then we followed our patients for 5 years and finally we have analyzed correlations between the levels of markers expressions with patients clinicopathological and prognostic criteria in cc-RCC.

RESULTS

Positive expression of SPOP & ZEB1 in addition to negative E- cadherin expression was detected in cc-RCC more than benign areas of neoplastic kidney specimens (p = 0.004 and p < 0.001 respectively). In cc-RCC Positive expression of SPOP, ZEB1 and negative E- cadherin expression was associated with higher grade (p = 0.006, 0.007 & <0.001 respectively), advanced AJCC stage (p = 0.013, 0.023 & <0.001 respectively), presence of L.N metastases (p = 0.002 = 0.010 and <0.001 respectively), distant metastases (p = 0.001, 0.003 & 0.035 respectively), poor PFS and OS rates (p < 0.001 and p = 0.013 respectively).

CONCLUSION

Positive expression of SPOP& ZEB1 in addition to negative E- cadherin are associated with poor prognosis in cc-RCC patients.