Serum and urine biomarkers for human renal cell carcinoma. Dis Markers. 2015;2015:251403. [PMID: 25922552 PMCID: PMC4398943 DOI: 10.1155/2015/251403]

Volatile Organic Metabolites as Potential Biomarkers for Genitourinary Cancers: Review of the Applications and Detection Methods

Cancer is one of the leading causes of death globally, and is ranked second in the United States. Early detection is crucial for more effective treatment and a higher chance of survival rates, reducing burdens on individuals and societies. Genitourinary cancers, in particular, face significant challenges in early detection. Finding new and cost-effective diagnostic methods is of clinical need. Metabolomic-based approaches, notably volatile organic compound (VOC) analysis, have shown promise in detecting cancer. VOCs are small organic metabolites involved in biological processes and disease development. They can be detected in urine, breath, and blood samples, making them potential candidates for sensitive and non-invasive alternatives for early cancer detection. However, developing robust VOC detection methods remains a hurdle. This review outlines the current landscape of major genitourinary cancers (kidney, prostate, bladder, and testicular), including epidemiology, risk factors, and current diagnostic tools. Furthermore, it explores the applications of using VOCs as cancer biomarkers, various analytical techniques, and comparisons of extraction and detection methods across different biospecimens. The potential use of VOCs in detection, monitoring disease progression, and treatment responses in the field of genitourinary oncology is examined.

Optical biomarker analysis for renal cell carcinoma obtained from preoperative and postoperative patients using ATR-FTIR spectroscopy

Renal cell carcinoma (RCC) is the most common malignant tumor in the urinary system, accounting for 80 % to 90 % for all renal malignancies. Traditional diagnostic methods like magnetic resonance imaging (MRI) and computed tomography (CT) lack the sensitivity and specificity as they lack specific biomarkers. These limitations impede effective monitoring of tumor recurrence. This study aims to employ Attenuated Total Reflection (ATR)-Fourier transform infrared (FTIR) spectroscopy, an optical technology sensitive to molecular groups, to analyze the potential optical biomarkers in urine and plasma samples from RCC patients pre- and post-surgery. The results reveal distinctive spectral information from both plasma and urine samples. Post-surgery urine spectra exhibit complexity compared to plasma, showing reduced content at 1072 cm-1, 1347 cm-1 and 1654 cm-1 bands, while increased content at 1112 cm-1, 1143 cm-1, 1447 cm-1, 3334 cm-1 and 3420 cm-1 bands. Utilizing machine learning models such as eXtreme Gradient Boosting (XGBoost), support vector machine (SVM), partial least squares (PLS), and artificial neural network (ANN), the study evaluated plasma and urine samples pre- and post-surgery. Remarkably, the XGBoost method excelled in distinguishing between tumor conditions and recovery, achieving an impressive AUC value of 0.99. These results underscore the potential of ATR-FTIR technology in identifying RCC optical biomarkers, with XGBoost showing promise as a valuable screening tool for RCC recurrence diagnosis.

Proteomics Analysis of Renal Cell Line Caki-2 with AFMID Overexpression and Potential Biomarker Discovery in Urine

Aromatic caninurine formamase (AFMID) is an enzyme involved in the tryptophan pathway, metabolizing N-formylkynurenine to kynurenine. AFMID had been found significantly downregulated in clear cell renal cell carcinoma (ccRCC) in both tissue and urine samples. Although ccRCC is characterized by a typical Warburg-like phenotype, mitochondrial dysfunction, and elevated fat deposition, it is unknown whether AFMID plays a role in tumorigenesis and the development of ccRCC. In the present study, AFMID overexpression had inhibitory effects for ccRCC cells, decreasing the rate of cell proliferation. Quantitative proteomics showed that AFMID overexpression altered cellular signaling pathways involved in cell growth and cellular metabolism pathways, including lipid metabolism and inositol phosphate metabolism. Further urine proteomic analysis indicated that cellular function dysfunction with AFMID overexpression could be reflected in the urine. The activity of predicted upregulators DDX58, TREX1, TGFB1, SMARCA4, and TNF in ccRCC cells and urine showed opposing change trends. Potential urinary biomarkers were tentatively discovered and further validated using an independent cohort. The protein panel of APOC3, UMOD, and CILP achieved an AUC value of 0.862 for the training cohort and 0.883 for the validation cohort. The present study is of significance in terms of highlighting various aspects of pathway changes associated with AFMID enzymes, discovering potential specific biomarkers for potential patient diagnosis, and therapeutic targeting.

Non-coding transcriptome profiles in clear-cell renal cell carcinoma

Clear-cell renal cell carcinoma (ccRCC) is a common urological malignancy with an increasing incidence. The development of molecular biomarkers that can predict the response to treatment and guide personalized therapy selection would substantially improve patient outcomes. Dysregulation of non-coding RNA (ncRNA) has been shown to have a role in the pathogenesis of ccRCC. Thus, an increasing number of studies are being carried out with a focus on the identification of ncRNA biomarkers in ccRCC tissue samples and the connection of these markers with patients' prognosis, pathological stage and grade (including metastatic potential), and therapy outcome. RNA sequencing analysis led to the identification of several ncRNA biomarkers that are dysregulated in ccRCC and might have a role in ccRCC development. These ncRNAs have the potential to be prognostic and predictive biomarkers for ccRCC, with prospective applications in personalized treatment selection. Research on ncRNA biomarkers in ccRCC is advancing, but clinical implementation remains preliminary owing to challenges in validation, standardization and reproducibility. Comprehensive studies and integration of ncRNAs into clinical trials are essential to accelerate the clinical use of these biomarkers.

Elevated serum gamma-glutamyltransferase activity and immunohistochemistry in two dogs with renal carcinoma

During a 3-year time period, a 15-year-old male castrated Terrier mix (dog 1) and a 6-year-old female spayed Labrador Retriever (dog 2) presented to the North Carolina State Veterinary Hospital with similar blood work abnormalities and no significant physical examination findings. A CBC, chemistry panel, and urinalysis performed on both dogs were relatively unremarkable, other than a marked increase in serum gamma-glutamyltransferase (GGT) activity. Through imaging, both patients were diagnosed with a renal mass, and histopathology of both masses revealed a carcinoma. Immunohistochemical staining of the renal mass in both dog 1 and dog 2 were intensely positive for GGT. Dog 1 had the affected kidney removed, which normalized the GGT value. Dog 2 was euthanized, and metastasis to the lung was noted upon postmortem examination. There have been limited case studies documenting an elevation in serum GGT in dogs diagnosed with renal carcinoma. While renal carcinoma is uncommon in dogs, it is an important differential to keep in mind when there is a marked increase in serum GGT without accompanying increases in other measured liver enzymes. In addition, serum GGT can serve as a helpful biomarker for disease resolution and recurrence, as surgical removal of the renal mass (dog 1) led to the resolution of the elevated serum GGT. To our knowledge, this is the first report demonstrating IHC staining for GGT in a canine renal carcinoma.

Urinary miRNAs Predict Metastasis in Patients With Clinically Localized Clear Cell Renal Cell Carcinoma Treated With Nephrectomy

PURPOSE

Patients with clear cell renal cell carcinoma (ccRCC) might develop metastasis after surgery with curative intent. We aimed to characterize the expression levels of microRNAs in the urine (UmiRNAs) of patients before and after nephrectomy to determine the impact of UmiRNAs expression in the emergence of metastases.

METHODS

We prospectively collected pre- and post-nephrectomy urine samples from 117 patients with clinically localized and locally advanced ccRCC. UmiRNAs were extracted, purified, and measured using RT-PCR. Relative quantifications (RQ) of 137 UmiRNAs were calculated through 2-∆∆ method. The post-surgery/pre-surgery RQs ratio represented the magnitude of the expression levels of the UmiRNAs. The association of UmiRNA expression and the development of distant metastases was tested with Cox regression model.

RESULTS

Five UmiRNAs (miR-191-5p, miR-324-3p, miR-186-5p, miR-93-5p, miR-30b-5p) levels were upregulated before nephrectomy (p < .05). This conferred a 2- to 4-fold increased risk of metastasis, with miR-191-5p showing the most significant association with this endpoint (HR = 4.16, 95% CI = 1.38-12.58, p = .011). In a multivariate model stratified with stage and Fuhrman grade, we found that miR-191-5p, miR-324-3p, and miR-186-5p exhibited a strong association with metastasis development in patients with pathological T3 (pT3) tumors. Enrichment analysis with the most differentially expressed UmiRNAs showed that these UmiRNAs targeted genes that regulate cell survival and proliferation.

CONCLUSION

Our study indicated UmiR-191-5p, UmiR-324-3p, and UmiR-186-5p are potential markers to predict the development of metastasis, particularly in pT3 patients.

PATIENT SUMMARY

We compared changes of UmiRNAs expression detected pre- and postnephrectomy of patients with ccRCC. Our findings suggest that UmiRNA expression likely reflects tumor-specific changes that can be promising to predict the metastasis development, particularly in patients with non-metastatic locally advanced ccRCC. If confirmed, these findings may be useful for surveillance protocols for adjuvant therapy protocols.

Urinary volatile organic compounds in prostate cancer biopsy pathologic risk stratification using logistic regression and multivariate analysis models

Prostate cancer (PCa) is the second leading cause of cancer-related death in American men after lung cancer. The current PCa diagnostic method, the serum prostate-specific antigen (PSA) test, is not specific, thus, alternatives are needed to avoid unnecessary biopsies and over-diagnosis of clinically insignificant PCa. To explore the application of metabolomics in such effort, urine samples were collected from 386 male adults aged 44-93 years, including 247 patients with biopsy-proven PCa and 139 with biopsy-proven negative results. The PCa-positive group was further subdivided into two groups: low-grade (ISUP Grade Group = 1; n = 139) and intermediate/high-grade (ISUP Grade Group ≥ 2; n = 108). Volatile organic compounds (VOCs) in urine were extracted by stir bar sorptive extraction (SBSE) and analyzed using thermal desorption with gas chromatography and mass spectrometry (GC-MS). We used machine learning tools to develop and evaluate models for PCa diagnosis and prognosis. In total, 22,538 VOCs were identified in the urine samples. With regularized logistic regression, our model for PCa diagnosis yielded an area under the curve (AUC) of 0.99 and 0.88 for the training and testing sets respectively. Furthermore, the model for differentiating between low-grade and intermediate/high-grade PCa yielded an average AUC of 0.78 based on a repeated test-sample approach for cross-validation. These novel methods using urinary VOCs and logistic regression were developed to fill gaps in PCa screening and assessment of PCa grades prior to biopsy. Our study findings provide a promising alternative or adjunct to current PCa screening and diagnostic methods to better target patients for biopsy and mitigate the challenges associated with over-diagnosis and over-treatment of PCa.

Unveiling the Dichotomy of Urinary Proteins: Diagnostic Insights into Breast and Prostate Cancer and Their Roles

This review covers the diagnostic potential of urinary biomarkers, shedding light on their linkage to cancer progression. Urinary biomarkers offer non-invasive avenues for detecting cancers, potentially bypassing the invasiveness of biopsies. The investigation focuses primarily on breast and prostate cancers due to their prevalence among women and men, respectively. The intricate interplay of urinary proteins is explored, revealing a landscape where proteins exhibit context-dependent behaviors. The review highlights the potential impact of physical activity on urinary proteins, suggesting its influence on tumorigenic behaviors. Exercise-conditioned urine may emerge as a potential diagnostic biomarker source. Furthermore, treatment effects, notably after lumpectomy and prostatectomy, induce shifts in the urinary proteome, indicating therapeutic impacts rather than activating oncogenic signaling. The review suggests further investigations into the double-sided, context-dependent nature of urinary proteins, the potential role of post-translational modifications (PTM), and the integration of non-protein markers like mRNA and metabolites. It also discusses a linkage of urinary proteomes with secretomes from induced tumor-suppressing cells (iTSCs). Despite challenges like cancer heterogeneity and sample variability due to age, diet, and comorbidities, harnessing urinary proteins and proteoforms may hold promise for advancing our understanding of cancer progressions, as well as the diagnostic and therapeutic role of urinary proteins.

Mesenchymal-Epithelial Transition Kinase Inhibitor Therapy in Patients with Advanced Papillary Renal-Cell Carcinoma: A Systematic Review and Meta-Analysis

Papillary subtypes of renal-cell carcinoma (pRCC) represent 10-15% of the cases and commonly have MET alterations. This systematic review and single-arm meta-analysis evaluated MET inhibitor therapy (METi) efficacy and safety in adults with confirmed advanced pRCC. The search strategy included PubMed, Web-of-science, Cochrane, and Scopus. We used the DerSimonian/Laird random effect model for all analyses; p-value < 5% was considered significant, and heterogeneity was assessed with I2. Three clinical trials and six cohort studies were included with 504 patients; 31% were MET-driven. Our pooled analysis demonstrated an objective response rate (ORR) in MET-driven, MET-independent, and overall patients of: 36% (95%CI: 10-62), 0% (95%CI: 0-3), and 21% (95%CI: 1-41), respectively. One-year disease control and progression-free survival rates were, respectively, 70% (95%CI: 52-88) and 15% (95%CI: 10-20). Twelve- and twenty-four-month survival rates were, respectively, 43% (95%CI: 23-64) and 10% (95%CI: 0-30). The prevalence of adverse events of any grade and grades 3-5 were 96% (95%CI: 91-100) and 44% (95%CI: 37-50), respectively. We suggest METi has anti-tumor activity and is tolerable in patients with advanced pRCC.

Investigating the effects of storage conditions on urinary volatilomes for their reliability in disease diagnosis

BACKGROUND

Cancer detection presents challenges regarding invasiveness, cost, and reliability. As a result, exploring alternative diagnostic methods holds significant clinical importance. Urinary metabolomic profiling has emerged as a promising avenue; however, its application for cancer diagnosis may be influenced by sample preparation or storage conditions.

OBJECTIVE

This study aimed to assess the impact of sample storage and processing conditions on urinary volatile organic compounds (VOCs) profiles and establish a robust standard operating procedure (SOP) for such diagnostic applications.

METHODS

Five key variables were investigated: storage temperatures, durations, freeze-thaw cycles, sample collection conditions, and sample amounts. The analysis of VOCs involved stir bar sorptive extraction coupled with thermal desorption-gas chromatography/mass spectrometry (SBSE-TD-GC-MS), with compound identification facilitated by the National Institute of Standards and Technology Library (NIST). Extensive statistical analysis, including combined scatterplot and response surface (CSRS) plots, partial least squares-discriminant analysis (PLS-DA), and probability density function plots (PDFs), were employed to study the effects of the factors.

RESULTS

Our findings revealed that urine storage duration, sample amount, temperature, and fasting/non-fasting sample collection did not significantly impact urinary metabolite profiles. This suggests flexibility in urine sample collection conditions, enabling individuals to contribute samples under varying circumstances. However, the influence of freeze-thaw cycles was evident, as VOC profiles exhibited distinct clustering patterns based on the number of cycles. This emphasizes the effect of freeze-thaw cycles on the integrity of urinary profiles.

CONCLUSIONS

The developed SOP integrating SBSE-TD-GC-MS and statistical analyses can serve as a valuable tool for analyzing urinary organic compounds with minimal preparation and sensitive detection. The findings also support that urinary VOCs for cancer screening and diagnosis could be a feasible alternative offering a robust, non-invasive, and sensitive approach for cancer screening.

Exploration into Plasma Hsa_circ_0052184 as a New Biomarker of Colorectal Cancer Prognosis

Background

Circular RNAs (circRNAs) are strong modulators of tumor pathology. Herein, our goal was to examine the plasma hsa_circ_0052184 content among colorectal cancer (CRC) patients, and assess its association with patient clinicopathological profile and diagnostic values.

Methods

Overall, we collected 228 presurgical CRC and 146 normal plasma samples from The First People's Hospital of Wenling. Circulating hsa_circ_0052184 levels were assessed via qRT-PCR, and the diagnostic prediction was conducted with the receiver operating characteristic (ROC) curve.

Results

Relative to healthy controls, CRC patients exhibited markedly enhanced circulating hsa_circ_0052184 levels, which were closely correlated with advanced stage of disease and worse outcome. Based on our uni- (UA) and multivariate assessments (MA), elevated hsa_circ_0052184 levels were a stand-alone predictor of poor prognosis. The ROC curve depicted an area under the curve (AUC) for CRC diagnosis to be 0.9072.

Conclusion

Circulating hsa_circ_0052184 is a potential bioindicator of CRC outcome.

The Roles of Extracellular Vesicles in the Progression of Renal Cell Carcinoma and Their Potential for Future Clinical Application

Renal cell carcinoma (RCC) is the most common type of kidney cancer and is thought to originate from renal tubular epithelial cells. Extracellular vesicles (EVs) are nanosized lipid bilayer vesicles that are secreted into extracellular spaces by nearly all cell types, including cancer cells and non-cancerous cells. EVs are involved in multiple steps of RCC progression, such as local invasion, host immune modulation, drug resistance, and metastasis. Therefore, EVs secreted from RCC are attracting rapidly increasing attention from researchers. In this review, we highlight the mechanism by which RCC-derived EVs lead to disease progression as well as the potential and challenges related to the clinical implications of EV-based diagnostics and therapeutics.

Human Urinary Volatilome Analysis in Renal Cancer by Electronic Nose

Currently, in clinical practice there are still no useful markers available that are able to diagnose renal cancer in the early stages in the context of population screening. This translates into very high costs for healthcare systems around the world. Analysing urine using an electronic nose (EN) provides volatile organic compounds that can be easily used in the diagnosis of urological diseases. Although no convincing results have been published, some previous studies suggest that dogs trained to sniff urine can recognize different types of tumours (bladder, lung, breast cancer) with different success rates. We therefore hypothesized that urinary volatilome profiling may be able to distinguish patients with renal cancer from healthy controls. A total of 252 individuals, 110 renal patients and 142 healthy controls, were enrolled in this pilot monocentric study. For each participant, we collected, stabilized (at 37 °C) and analysed urine samples using a commercially available electronic nose (Cyranose 320^®). Principal component (PCA) analyses, discriminant analysis (CDA) and ROC curves were performed to provide a complete statistical analysis of the sensor responses. The best discriminating principal component groups were identified with univariable ANOVA analysis. The study correctly identified 79/110 patients and 127/142 healthy controls, respectively (specificity 89.4%, sensitivity 71.8%, positive predictive value 84.04%, negative predictive value 80.37%). In order to test the study efficacy, the Cross Validated Accuracy was calculated (CVA 81.7%, p < 0.001). At ROC analysis, the area under the curve was 0.85. The results suggest that urine volatilome profiling by e-Nose seems a promising, accurate and non-invasive diagnostic tool in discriminating patients from controls. The low costs and ease of execution make this test useful in clinical practice.

Serum C-NLR score, a new inflammatory marker, predicts tumor histopathology and oncological outcomes of localized clear cell renal carcinoma after nephrectomy: A single center retrospective analysis

Background/Aim: Several blood and serum-based parameters have been described as prognostic markers of clear cell renal cell carcinoma (ccRCC). But most of these markers have inconsistent results and are not used in routine clinical practice. Therefore, novel potential predictor biomarkers are needed for the management of ccRCC patients in clinical practice. Here, we investigate the predictive value of a novel marker, serum C-NLR score, for pathological characteristics and oncological outcomes of ccRCC. Methods: A total of 162 RCC patients who underwent radical or partial nephrectomy between January 2015 and January 2021 were evaluated in a retrospective cohort study setting. The serum C-NLR score was compared according to the tumor histopathology-associated parameters. The predictive role of those parameters and C-NLR score on the oncological outcomes of ccRCC was also investigated. Results: The median serum C-NLR scores exhibited statistically significant increases in ccRCC patients with pathological necrosis, lymphovascular invasion, and variant differentiation. Among histopathological characteristics, only tumor necrosis and variant differentiation were associated with overall survival (OS) and tumor grade with metastasis-free survival (MFS) (no metastasis detected in grade 1–2 tumors) in Kaplan Meier analyses. Serum C-NLR score was also associated with OS but not MFS. In the univariate analyses, tumor necrosis, variant differentiation, and C-NLR score were associated with OS of localized RCC patients who underwent nephrectomy (HR: 0.29; 95% CI: 0.08–1.01; P=0.04, HR: 6.01; 95% CI: 1.66–21.82; P=0.006 and, HR: 1.21; 95% CI: 0.20–5.16; P=0.04). However, in the multivariate analysis, only variant differentiation and C-NLR score were associated with OS (HR: 1.43; 95% CI: 0.82–2.98; P=0.03 and HR: 1.21; 95% CI: 0.20–5.16; P=0.04). Tumor grade was directly associated with MFS because grade 1–2 tumors did not exhibit any metastasis. Conclusion: Serum C-NLR score was higher in worse histopathological entities. Moreover, it predicts the OS for patients with ccRCC as an independent factor.

Can microRNAs be utilized as tumor markers for recurrence following nephrectomy in renal cell carcinoma patients? A meta-analysis provides the answer

INTRODUCTION

Renal cell carcinoma (RCC) is an aggressive tumor. Many studies investigated microRNAs (miRs) as RCC prognostic biomarkers, often reporting inconsistent findings. We present a meta-analysis to identify if tissue-derived miRs can be used as a prognostic factor in patients after nephrectomy.

METHODS

Data were obtained from PubMed, Embase, and Web of Science. The hazard ratio with 95% confidence intervals assessed the prognostic value of microRNAs. Outcomes of interest included the prognosis role of microRNAs in overall survival (OS), recurrence-free survival (RFS), and cancer-specific survival (CSS) in nephrectomy patients.

RESULTS

Nine retrospective studies that evaluated microRNAs in 1,541 nephrectomy patients were collected. There were heterogeneities across studies for microRNAs in the 15 studies examining OS, RFS, and CSS (I² = 84.51%; P < 0.01); the random-effect model was calculated (HR = 1.371; (95% CI: 0.831-2.260); P = 0.216).

CONCLUSION

Our study indicated that miRNAs cannot be used as a marker for recurrence in RCC patients after nephrectomy, and researchers shouldn't make the mistake that if miRs can be used as a biomarker in RCC, they cannot be used as a marker after nephrectomy in RCC. As all of these findings were from retrospective studies, further studies are needed to verify the role of microRNAs in clinical trials.

Biomarkers in Urological Cancers

Urological tumours have become one of the most common cancers in the last decade. It is important to apply an approach that evaluates many factors related to the patient and the disease carefully to minimize cancer-associated morbidity and mortality. The clinical use of cancer biomarkers is a valuable part of the clinical management of urological cancers. These biomarkers may lead to optimized detection, treatment, and follow-up of urological cancers. With the development of molecular research, newly developed biomarkers and next-generation sequencing have also contributed to patient management. In this chapter, we will present biomarkers in the most common urological cancers under subheadings of bladder cancer, prostate cancer, kidney cancer, and testicular cancer. Additionally, due to the development that occurred in the next-generation sequencing (NGS), all the above-mentioned malignancies are evaluated with regard to NGS.

The Current Status of Kidney Cancer Urine Markers – A Systematic Review

BACKGROUND: Renal cell carcinoma is the 9th most common malignant disease in the Western World. Typically, patients develop symptoms in a late stage of the disease and most of them are diagnosed by chance. Up to 30% of the patients at the time of diagnosis had metastatic disease. Therefore, highly specific and sensitive biomarkers for the detection and progression of kidney cancer are of great importance. Here, urine markers can be a major advantage and can have a huge clinical impact on the diagnosis, differentiation and prognosis of kidney cancer. At the moment there are several approaches to improve these conditions.. METHODS: A systematic literature research was performed according to the PRISMA guidelines to identify studies reporting urine markers for kidney cancer between 2012 and 2021. A two-step process for the selection of the studies was initiated. In total 287 studies were considering for the final analysis. In total, 6 studies, which presented potential urinary biomarker were analyzed in depth. RESULTS: The major focus was on urinary markers for the detection, progression and differentiation of renal cell carcinoma. In total, a study population of 1099 patients were investigated in the different studies that were analyzed in depth. The median patient sample size of the different studies was 157 patients. The focus was based on the investigation of different microRNAs and proteins as urinary marker for kidney cancer detection. CONCLUSION: Overall, there are different approaches present for the detection, prognosis and differentiation of kidney cancer in urine but most of the studies are based on a small sample size and need to be validated in a greater collective. Furthermore, the standard should be improved to bring these biomarkers into routine clinical practice.

Semaphorin 6D as an independent predictor for better prognosis in clear cell renal cell carcinoma

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The role of SEMA6D in clear cell renal cell carcinoma remains unexplored.

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SEMA6D expression was markedly lower in ccRCC tissues compared to normal tissues.

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SEMA6D may serve as a diagnostic and prognostic biomarker for ccRCC.

Introduction

Clear cell renal cell carcinoma (ccRCC) is the most common type of RCC and is associated with poor survival. However, the mechanisms underlying its development have not been thoroughly investigated. Semaphorin 6D (SEMA6D) is differentially expressed in various cancers, including lung adenocarcinoma and colorectal cancer. However, the role and mechanism of SEMA6D in ccRCC remain unexplored.

Materials and methods

We obtained 25 pairs of ccRCC tissue samples and 57 urine samples from patients with ccRCC and 52 urine samples from healthy volunteers. We performed RNA sequencing and compared the results with data from The Cancer Genome Atlas database to identify our gene of interest, SEMA6D. To verify the differential expression of SEMA6D, we used real-time quantitative polymerase chain reaction, immunohistochemistry, and enzyme-linked immunosorbent assay. Finally, we conducted in vitro proliferation, migration and invasion experiments.

Results

SEMA6D expression was significantly lower in ccRCC tissue compared to that in normal tissue. Comparative analysis of our results with data from online databases revealed that the expression level of SEMA6D in ccRCC tissue correlated with the clinical stage and pathological grade of ccRCC. Furthermore, higher SEMA6D expression was associated with improved quality of life of patients with ccRCC. In addition, the diagnostic value of SEMA6D was confirmed using data from two Gene Expression Omnibus ccRCC databases. The results showed that SEMA6D can be used as a predictor for ccRCC diagnosis, with an area under the curve of 0.9642.

Conclusion

SEMA6D may serve as a diagnostic and prognostic biomarker for ccRCC.

MALDI-TOF/MS Analysis of Non-Invasive Human Urine and Saliva Samples for the Identification of New Cancer Biomarkers

Cancer represents a group of heterogeneous diseases that are a leading global cause of death. Even though mortality has decreased in the past thirty years for different reasons, most patients are still diagnosed at the advanced stage, with limited therapeutic choices and poor outcomes. Moreover, the majority of cancers are detected using invasive painful methods, such as endoscopic biopsy, making the development of non-invasive or minimally invasive methods for the discovery and fast detection of specific biomarkers a crucial need. Among body fluids, a valuable non-invasive alternative to tissue biopsy, the most accessible and least invasive are undoubtedly urine and saliva. They are easily retrievable complex fluids containing a large variety of endogenous compounds that may provide information on the physiological condition of the body. The combined analysis of these fluids with matrix-assisted laser desorption ionization–time-of-flight mass spectrometry (MALDI-TOF/MS), a reliable and easy-to-use instrumentation that provides information with relatively simple sample pretreatments, could represent the ideal option to rapidly achieve fast early stage diagnosis of tumors and their real-time monitoring. On this basis, the present review summarizes the recently reported applications relevant to the MALDI analysis of human urine and saliva samples.

Ubiquitin-specific peptidase 2 inhibits epithelial-mesenchymal transition in clear cell renal cell carcinoma metastasis by downregulating the NF-κB pathway

Clear cell renal cell carcinoma, the most common type of renal cancer, is associated with poor survival. Ubiquitin-specific peptidase 2 regulates the molecular mechanisms of cancer cells. However, its mechanism in clear cell renal cell carcinoma remains unclear. Quantitative real-time polymerase chain reaction, enzyme-linked immunosorbent assay, and immunohistochemistry were performed to assess ubiquitin-specific peptidase 2 expression in human clear cell renal cell carcinoma samples. Ubiquitin-specific peptidase 2 was weakly expressed in clear cell renal cell carcinoma samples and associated with poor patient outcomes. Ubiquitin-specific peptidase 2 inhibition promoted clear cell renal cell carcinoma cell proliferation, migration, and invasion. Ubiquitin-specific peptidase 2 overexpression inhibited clear cell renal cell carcinoma cell proliferation, migration, and invasion in vitro and in vivo. RNA-sequencing showed significant changes in the epithelial-mesenchymal transition-related pathways following ubiquitin-specific peptidase 2 knockdown. Western blotting was performed to detect the protein expression levels. Expression of p-nuclear factor-κB p65, N-cadherin, Vimentin, and Snail, which were markedly increased, as well as E-cadherin, which was decreased following ubiquitin-specific peptidase 2 knockdown. Rescue experiments using the nuclear factor-κB inhibitor BAY 11–7082 revealed that the migration and invasion abilities and the expression of epithelial-mesenchymal transition pathway proteins were inhibited in both the short hairpin RNA (shRNA) for ubiquitin-specific peptidase 2 and shRNA for negative control groups. Ubiquitin-specific peptidase 2 is a potential biomarker to distinguish clear cell renal cell carcinoma patients from healthy individuals. Ubiquitin-specific peptidase 2-mediated inhibition of epithelial-mesenchymal transition in clear cell renal cell carcinoma cells is dependent on the nuclear factor-κB pathway.

SERS Liquid Biopsy Profiling of Serum for the Diagnosis of Kidney Cancer

Renal cancer (RC) represents 3% of all cancers, with a 2% annual increase in incidence worldwide, opening the discussion about the need for screening. However, no established screening tool currently exists for RC. To tackle this issue, we assessed surface-enhanced Raman scattering (SERS) profiling of serum as a liquid biopsy strategy to detect renal cell carcinoma (RCC), the most prevalent histologic subtype of RC. Thus, serum samples were collected from 23 patients with RCC and 27 controls (CTRL) presenting with a benign urological pathology such as lithiasis or benign prostatic hypertrophy. SERS profiling of deproteinized serum yielded SERS band spectra attributed mainly to purine metabolites, which exhibited higher intensities in the RCC group, and Raman bands of carotenoids, which exhibited lower intensities in the RCC group. Principal component analysis (PCA) of the SERS spectra showed a tendency for the unsupervised clustering of the two groups. Next, three machine learning algorithms (random forest, kNN, naïve Bayes) were implemented as supervised classification algorithms for achieving discrimination between the RCC and CTRL groups, yielding an AUC of 0.78 for random forest, 0.78 for kNN, and 0.76 for naïve Bayes (average AUC 0.77 ± 0.01). The present study highlights the potential of SERS liquid biopsy as a diagnostic and screening strategy for RCC. Further studies involving large cohorts and other urologic malignancies as controls are needed to validate the proposed SERS approach.

Early detection of kidney cancer using urinary proteins: a truly non-invasive strategy

OBJECTIVES

To review urinary protein biomarkers as potential non-invasive, easily obtainable, early diagnostic tools in renal cell carcinoma (RCC).

METHODS

A PubMed database search was performed up to the year 2020 to identify primary studies reporting potential urinary protein biomarkers for RCC. Separate searches were conducted to identify studies describing appropriate methods of developing cancer screening programmes and detection of cancer biomarkers.

RESULTS

Several urinary protein biomarkers are under validation for RCC diagnostics, e.g. aquaporin-1, perilipin-2, carbonic anhydrase-9, Raf-kinase inhibitory protein, nuclear matrix protein-22, 14-3-3 Protein β/α and neutrophil gelatinase-associated lipocalin. However, none has yet been validated or approved for clinical use due to low sensitivity or specificity, inconsistencies in appropriate study design, or lack of external validation.

CONCLUSIONS

Evaluation of biomarkers' feasibility, sample preparation and storage, biomarker validation, and the application of novel technologies may provide a solution that maximises the potential for a truly non-invasive biomarker in early RCC diagnostics.

Serum and urine analysis with gold nanoparticle-assisted laser desorption/ionization mass spectrometry for renal cell carcinoma metabolic biomarkers discovery

PURPOSE

Renal cell carcinoma (RCC) is a very aggressive and often fatal heterogeneous disease that is usually asymptomatic until late in the disease. There is an urgent need for RCC specific biomarkers that may be exploited clinically for diagnostic and prognostic purposes.

MATERIALS/METHODS

Serum and urine samples were collected from patients with diagnosed kidney cancer and assessed with gold nanoparticle enhanced target (AuNPET) surface assisted-laser desorption/ionization mass spectrometry (SALDI MS) based metabolomics and statistical analysis.

RESULTS

A database search allowed providing assignment of signals for the most promising features with a satisfactory value of the area under the curve and accuracy. Four potential biomarkers were found in urine and serum samples to distinguish clear cell renal cell carcinoma (ccRCC) from controls, 4 for the ccRCC with and without metastases, and 6 metabolites to distinguish low and high stages or grades.

CONCLUSIONS

This pilot study suggests that serum and urine metabolomics based on AuNPET-LDI MS may be useful in distinguishing types, grades and stages of human RCC.

Urine LOX-1 and Volatilome as Promising Tools towards the Early Detection of Renal Cancer

Simple Summary

Renal cell carcinoma (RCC) is often late diagnosed at an advanced stage, worsening the prognosis of the patients. Thus, an early marker is desirable. This paper presents an innovative combined approach useful to identify, for the first time, the presence of LOX-1 protein within the urine of clear cell RCC patients. The LOX-1 protein is related to metabolic disorder-associated carcinogenesis and is shown to be quantitatively correlated to tumor grade and stage. The analysis of volatile compounds released by urine shows the diagnostic potentialities of volatilome and indicates that at least one volatile compound is correlated with both LOX-1 and cancer. In this work, we propose the potential use of a noninvasive approach that enables an early, routine ccRCC diagnosis and leads to a better management of the patients.

Abstract

Renal cell carcinoma (RCC) represents around 3% of all cancers, within which clear cell RCC (ccRCC) are the most common type (70–75%). The RCC disease regularly progresses asymptomatically and upon presentation is recurrently metastatic, therefore, an early method of detection is necessary. The identification of one or more specific biomarkers measurable in biofluids (i.e., urine) by combined approaches could surely be appropriate for this kind of cancer, especially due to easy obtainability by noninvasive method. OLR1 is a metabolic gene that encodes for the Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), implicated in inflammation, atherosclerosis, ROS, and metabolic disorder-associated carcinogenesis. Specifically, LOX-1 is clearly involved in tumor insurgence and progression of different human cancers. This work reports for the first time the presence of LOX-1 protein in ccRCC urine and its peculiar distribution in tumoral tissues. The urine samples headspace has also been analyzed for the presence of the volatile compounds (VOCs) by SPME-GC/MS and gas sensor array. In particular, it was found by GC/MS analysis that 2-Cyclohexen-1-one,3-methyl-6-(1-methylethyl)- correlates with LOX-1 concentration in urine. The combined approach of VOCs analysis and protein quantification could lead to promising results in terms of diagnostic and prognostic potential for ccRCC tumors.

SPARC is a key mediator of TGF-β-induced renal cancer metastasis

Aberrant expression of transforming growth factor-β1 (TGF-β1) is associated with renal cell carcinoma (RCC) progression by inducing cancer metastasis. However, the downstream effector(s) in TGF-β signaling pathway is not fully characterized. In the present study, the elevation of secreted protein acidic and rich in cysteine (SPARC) as a TGF-β regulated gene in RCC was identified by applying differentially expressed gene analysis and microarray analysis, we further confirmed this result in several RCC cell lines. Clinically, the expression of these two genes is positively correlated in RCC patient specimens. Furthermore, elevated SPARC expression is found in all the subtypes of RCC and positively correlated with the RCC stage and grade. In contrast, SPARC expression is inversely correlated with overall and disease-free survival of patients with RCC, suggesting SPARC as a potent prognostic marker of RCC patient survival. Knocking down SPARC significantly inhibits RCC cell invasion and metastasis both in vitro and in vivo. Similarly, in vitro cell invasion can be diminished by using a specific monoclonal antibody. Mechanistically, SPARC activates protein kinase B (AKT) pathway leading to elevated expression of matrix metalloproteinase-2 that can facilitate RCC invasion. Altogether, our data support that SPARC is a critical role of TGF-β signaling network underlying RCC progression and a potential therapeutic target as well as a prognostic marker.

Acylated ghrelin protects against doxorubicin-induced nephropathy by activating silent information regulator 1

This study investigated the nephroprotective role of acylated ghrelin (AG) against DOX-induced nephropathy and examined whether the protection involves silent information regulator 1 (SIRT1). Rats were divided into control, control + AG, DOX, DOX + AG, DOX + AG + [D-Lys3]-GHRP-6 (a ghrelin receptor antagonist), and DOX + AG + EX-527 (a sirt1 inhibitor). DOX was given over the first 2 weeks. AG (10 ng/kg) and both inhibitors were given as 3 doses/wk for 5 weeks. AG improved the structure and the function of the kidneys; down-regulated the renal expression of TGF-β1, collagen 1A1 and α-SMA; and inhibited the renal collagen deposition in the kidneys of DOX-treated rats. Concomitantly, it reduced the renal levels of ROS, MDA, TNF-α, and IL-6 and protein levels of cytochrome-c, TGF-β1, Smad3 and α-SMA in these rats. In both the control and DOX-treated rats, AG significantly increased the renal levels of SOD and GSH, decreased the expression of cleaved caspase-3 and Bax, increased the total levels and the nuclear activity of SIRT1 and reduced the deacetylation of p53, NF-κB and FOXO-31. All the effects were abolished by the concurrent administration of EX-527 and [D-Lys3]-GHRP-6. In conclusion, AG prevents DOX-induced nephropathy in SIRT1 and GSHRa1-dependent mechanism.

Patient-derived tumour models for personalized therapeutics in urological cancers

Preclinical knowledge of dysregulated pathways and potential biomarkers for urological cancers has undergone limited translation into the clinic. Moreover, the low approval rate of new anticancer drugs and the heterogeneous drug responses in patients indicate that current preclinical models do not always reflect the complexity of malignant disease. Patient-derived tumour models used in preclinical uro-oncology research include 3D culture systems, organotypic tissue slices and patient-derived xenograft models. Technological innovations have enabled major improvements in the capacity of these tumour models to reproduce the clinical complexity of urological cancers. Each type of patient-derived model has inherent advantages and limitations that can be exploited, either alone or in combination, to gather specific knowledge on clinical challenges and address unmet clinical needs. Nevertheless, few opportunities exist for patients with urological cancers to benefit from personalized therapeutic approaches. Clinical validation of experimental data is needed to facilitate the translation and implementation of preclinical knowledge into treatment decision making.

Identification of plasma hsa_circ_0008673 expression as a potential biomarker and tumor regulator of breast cancer

OBJECTIVE

Cell-free circular RNAs (circRNAs) are stable and abundantly exist in body fluids. In this study, we aimed to investigate plasma cell-free circRNAs as a novel class of biomarkers for the diagnosis of breast cancer (BC).

METHODS

Differentially expressed circRNAs from 6 normal and 6 BC plasma samples were detected by microarray. Hsa_circ_0008673 was then screened and validated in the plasma of 102 normal and 378 BC samples. A receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value. The correlations between hsa_circ_0008673 expression and demographic characteristics, tumor features, and prognosis were analyzed. The effects of hsa_circ_0008673 on BC cell proliferation and metastasis were also measured.

RESULTS

Of the top ten up-regulated (hsa_circ_0008673, hsa_circ_0008500, hsa_circ_0005260, hsa_circ_0003423, hsa_circ_0119881, hsa_circ_0000987, hsa_circ_0007386, hsa_circ_0000091, hsa_circ_0016601, and hsa_circ_0008549) and top ten down-regulated (hsa_circ_0000826, hsa_circ_0072697, hsa_circ_0004587, hsa_circ_0000471, hsa_circ_0007786, hsa_circ_0001417, hsa_circ_0005982, hsa_circ_0001566, hsa_circ_0003823, and hsa_circ_0003823) circRNAs from microarray, hsa_circ_0008673 was the most significantly up-regulated circRNA in BC, and represented a good diagnostic value. Hsa_circ_0008673 was remarkably down-regulated after breast mastectomy. Hsa_circ_0008673 expression was associated with larger tumor size, distant metastasis, positive estrogen receptor (ER) status, and positive progesterone receptor (PR) status. Additionally, hsa_circ_0008673 could serve as a prognostic predicator of overall survival (OS) and disease-specific survival (DSS). Cell assays proved that hsa_circ_0008673 knockdown contributed to inhibition of tumor cell proliferation and migration.

CONCLUSION

Plasma cell-free hsa_circ_0008673 was up-regulated in BC, which was associated with poorer prognosis and promoted tumor proliferation and metastasis. Hsa_circ_0008673 is a promising biomarker for tumor diagnosis and prognostic assessment of BC patients.

Emerging role of secreted miR-210-3p as potential biomarker for clear cell Renal Cell Carcinoma metastasis

BACKGROUND

MicroRNAs (miRNAs) are emerging as promising molecules in the diagnosis, prognosis and treatment of urological tumours. Recently, our group performed two independent studies highlighting that miR-210-3p may be a useful biomarker not only for diagnosis but also for post-surgery clear cell Renal Cell Carcinoma (ccRCC) management.

OBJECTIVE

The aim of this study is to further explore the effectiveness of miRNA as non-invasive biomarker for clinical outcomes and ccRCC response to the treatment.

METHODS

We analyzed miR-210-3p levels in neoplastic and healthy tissue and in urine specimens collected at surgery and during follow-up of 21 ccRCC patients by RTqPCR.

RESULTS

Firstly, we confirmed that the expression of miR-210-3p was upregulated in tumor tissues and in urine samples of analyzed cohort. Of note is that miR-210-3p expression was significantly reduced in urine samples from disease-free patients during follow-up (from 3 to 12 months) compared to the baseline levels observed at the time of surgery. In a small subgroup of patients presenting metastatic progression (such as bone, intestinal or lung metastasis), the urine levels of miR-210-3p correlated with responsiveness to the therapy.

CONCLUSIONS

This pilot study highlights the relevance of secreted miR-210-3p as powerful non-invasive prognostic and predictive biomarker for the evaluation of clinical outcomes and treatment response during ccRCC follow up.

Value of Ferritin Heavy Chain (FTH1) Expression in Diagnosis and Prognosis of Renal Cell Carcinoma

BACKGROUND Serum ferritin is a useful tumor marker for renal cell carcinoma (RCC). However, the expression of ferritin heavy chain (FTH1), the main subunit of ferritin, is unclear in primary RCC tissues. In this study, we investigated FTH1 mRNA expression and its diagnostic and prognostic value in RCC. MATERIAL AND METHODS The mRNA expression of FTH1 was analyzed using including Oncomine, Gene Expression Omnibus, and Cancer Genome Atlas datasets, while the protein level of FTH1 was analyzed using the Human Protein Atlas database. The associations between FTH1 and clinicopathologic characteristics and survival time and Cox multivariate survival analysis were analyzed using SPSS 22.0 software. A meta-analysis was performed to assess consistency of FTH1 expression. GO, KEGG, and PPI analyses were used to predict biological functions. RESULTS According to TCGA data, overexpression of FTH1 was detected in 890 RCC tissues (15.2904±0.63157) compared to 129 normal kidney tissues (14.4502±0.51523, p<0.001). Among the clinicopathological characteristics evaluated, patients with increased pathologic T staging, lymph node metastasis, and distant metastasis were significantly associated with higher expression of FTH1. Elevated FTH1 mRNA levels were correlated with worse prognosis of RCC patients. Cox multivariate survival analysis indicated that age, stage, and M stage were predictors of poor prognosis in patients with RCC. CONCLUSIONS Our data suggest that FTH1 expression is an effective prognostic and diagnosis biomarker for RCC.

Development of biomarkers of genitourinary cancer using mass spectrometry-based clinical proteomics

Prostate, bladder and kidney cancer are the three most common types of genitourinary cancer in the world. Of these, prostate and bladder cancers are within the top 10 most common cancers in men. Notably, kidney cancer causes no obvious symptoms in the early stages. To satisfy clinical-management requirements, researchers have developed numerous biomarkers by applying proteomic approaches using clinical serum, urine and tissue specimens, as well as cell and animal models. Through application of biomarker pipeline protocols, including discovery, verification and validation phases, and mass-spectrometric based proteomic platforms coupled with multiplexed quantification assays, these studies have led to recent rapid progress in this area. With improvements in mass-spectrometric based proteomic techniques, numerous promising biomarker candidates and marker panels for various clinical purposes have been proposed. Verification of novel protein biomarker candidates is very resource demanding (e.g. on the clinical and laboratory sides). With the support of national consortia, it is now possible to investigate the future clinical use of such biomarker strategies and assess their cost-effectiveness in personalized medicine.

Autoantibody against arrestin-1 as a potential biomarker of renal cell carcinoma

Renal cell carcinoma (RCC) is the second-most common uronephrological cancer. In the absence of specific symptoms, early diagnosis of RCC is challenging. Monitoring of the aberrant expression of tumour-associated antigens (TAAs) and related autoantibody response is considered as a novel approach of RCC diagnostics. The aim of this study was to examine the aberrant expression of arrestin-1 in renal tumours, to investigate the possible epigenetic mechanism underlying arrestin-1 expression, and to assess the frequency of anti-arrestin-1 autoantibody response. Immunohistochemistry was used to assess the presence of arrestin-1 in primary tumours and metastases of 39 patients with RCC and renal oncocytoma. Bisulfite sequencing was employed to analyse the methylation status of the promoter of the SAG gene encoding arrestin-1. Western blot analysis was performed to detect autoantibodies against arrestin-1 in serum samples of 36 RCC and oncocytoma patients. Arrestin-1 was found to be expressed in RCC (58.7% of cases) and renal oncocytoma (90% of cases) cells, while being absent in healthy kidney. The expression of arrestin-1 in RCC metastases was more prominent than in primary tumours. Hypomethylation of the SAG gene promoter is unlikely to be the mechanism for the aberrant expression of arrestin-1. Autoantibodies against arrestin-1 were detected in sera of 75% of RCC patients. Taken together, our findings suggest employment of autoantibody against arrestin-1 as biomarker of RCC.

Plasma Glycosaminoglycans as Diagnostic and Prognostic Biomarkers in Surgically Treated Renal Cell Carcinoma

BACKGROUND

Plasma glycosaminoglycan (GAG) measurements, when aggregated into diagnostic scores, accurately distinguish metastatic clear-cell renal cell carcinoma (RCC) from healthy samples and correlate with prognosis. However, it is unknown if GAG scores can detect RCC in earlier stages or if they correlate with prognosis after surgery.

OBJECTIVE

To explore the sensitivity and specificity of plasma GAGs for detection of early-stage RCC and prediction of recurrence and death after RCC surgery.

DESIGN, SETTING, AND PARTICIPANTS

This was a retrospective case-control study consisting of a consecutive series of 175 RCC patients surgically treated between May 2011 and February 2014 and 19 healthy controls.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Plasma GAGs in preoperative and postoperative RCC and healthy samples were measured using capillary electrophoresis with laser-induced fluorescence in a single blinded laboratory. A discovery set was first analyzed to update the historical GAG score. The sensitivity of the new GAG score for RCC detection versus healthy subjects was validated using the remaining samples. The correlation of the new GAG score to histopathologic variables, overall survival, and recurrence-free survival was evaluated using nonparametric and log-rank tests and multivariable Cox regression analyses.

RESULTS AND LIMITATIONS

The RCC cohort included 94 stage I, 58 stage II-III, and 22 stage IV cases. In the first discovery set (n=67), the new GAG score distinguished RCC from healthy samples with an area under the receiver operating characteristic curve (AUC) of 0.999. In the validation set (n=108), the GAG score achieved an AUC of 0.991, with 93.5% sensitivity. GAG scores were elevated in RCC compared to healthy samples, irrespective of and uncorrelated to stage, grade, histology, age, or gender. The total chondroitin sulfate concentration was an independent prognostic factor for both overall and recurrence-free survival (hazard ratios 1.51 and 1.25) with high concordance when combined with variables available at pathologic diagnosis (C-index 0.926 and 0.849) or preoperatively (C-index 0.846 and 0.736). Limitations of the study include its retrospective nature and moderate variability in GAG laboratory measurements.

CONCLUSIONS

Plasma GAGs are highly sensitive diagnostic and prognostic biomarkers in surgically treated RCC independent of stage, grade, or histology. Prospective validation studies on GAG scores for early detection, prediction, and surveillance for RCC recurrence are thus warranted.

PATIENT SUMMARY

In this study, we examined if a new molecular blood test can detect renal cell carcinoma in the early stages and predict if the cancer might relapse after surgery. The trial is registered on ClinicalTrial.gov as NCT03471897.

Racial Disparities and Preventive Measures to Renal Cell Carcinoma

Kidney cancer ranks among the top 10 cancers in the United States. Although it affects both male and female populations, it is more common in males. The prevalence rate of renal cell carcinoma (RCC), which represents about 85% of kidney cancers, has been increasing gradually in many developed countries. Family history has been considered as one of the most relevant risk factors for kidney cancer, although most forms of an inherited predisposition for RCC only account for less than four percent. Lifestyle and other factors such as occupational exposure, high blood pressure, poor diet, and heavy cigarette smoking are highly associated with its incidence and mortality rates. In the United States, White populations have the lowest prevalence of RCC compared to other ethnic groups, while Black Americans suffer disproportionally from the adverse effects of RCC. Hence, this review article aims at identifying the major risk factors associated with RCC and highlighting the new therapeutic approaches for its control/prevention. To achieve this specific aim, articles in peer-reviewed journals with a primary focus on risk factors related to kidney cancer and on strategies to reduce RCC were identified. The review was systematically conducted by searching the databases of MEDLINE, PUBMED Central, and Google Scholar libraries for original articles. From the search, we found that the incidence and mortality rates of RCC are strongly associated with four main risk factors, including family history (genetics), lifestyle (poor diet, cigarette smoking, excess alcohol drinking), environment (community where people live), and occupation (place where people work). In addition, unequal access to improvement in RCC cancer treatment, limited access to screening and diagnosis, and limited access to kidney transplant significantly contribute to the difference observed in survival rate between African Americans and Caucasians. There is also scientific evidence suggesting that some physicians contribute to racial disparities when performing kidney transplant among minority populations. New therapeutic measures should be taken to prevent or reduce RCC, especially among African Americans, the most vulnerable population group.

Surveillance following surgery for nonmetastatic renal cell carcinoma

PURPOSE OF REVEIW

Approximately one in three patients with nonmetastatic renal cell carcinoma (RCC) at the time of surgery will subsequently develop local or metastatic recurrence. The purpose of this review is to examine the current rationale for surveillance, describe sites of RCC metastasis, evaluate the existing guidelines for postsurgical follow-up studies, and analyze the risk stratification systems following RCC surgery.

RECENT FINDINGS

Although 75% of recurrences will be identified during the first 5 years following surgery, late recurrences are not uncommon. The risk of recurrence can be predicted from the tumor stage, grade, and other pathologic features. Advanced risk stratification will likely be possible in the future with increased use of molecular classification and serum biomarkers. Patient comorbidities, age, and individual recurrence risk should also be considered when designing individualized surveillance protocols.

SUMMARY

Follow-up after surgery for RCC should focus on imaging of the chest and abdomen to detect common sites of recurrence. Patients should be stratified for risk, and surveillance imaging should be more frequent and intensive in healthy patients with higher risk. Future research is needed to define an optimal individualized surveillance strategy that balances the potential benefits of early cancer detection with the risks and cost of surveillance.

The tyrosine-kinase inhibitor sunitinib targets vascular endothelial (VE)-cadherin: a marker of response to antitumoural treatment in metastatic renal cell carcinoma

Background

Vascular endothelial (VE)-cadherin is an endothelial cell-specific protein responsible for endothelium integrity. Its adhesive properties are regulated by post-translational processing, such as tyrosine phosphorylation at site Y⁶⁸⁵ in its cytoplasmic domain, and cleavage of its extracellular domain (sVE). In hormone-refractory metastatic breast cancer, we recently demonstrated that sVE levels correlate to poor survival. In the present study, we determine whether kidney cancer therapies had an effect on VE-cadherin structural modifications and their clinical interest to monitor patient outcome.

Methods

The effects of kidney cancer biotherapies were tested on an endothelial monolayer model mimicking the endothelium lining blood vessels and on a homotypic and heterotypic 3D cell model mimicking tumour growth. sVE was quantified by ELISA in renal cell carcinoma patients initiating sunitinib (48 patients) or bevacizumab (83 patients) in the first-line metastatic setting (SUVEGIL and TORAVA trials).

Results

Human VE-cadherin is a direct target for sunitinib which inhibits its VEGF-induced phosphorylation and cleavage on endothelial monolayer and endothelial cell migration in the 3D model. The tumour cell environment modulates VE-cadherin functions through MMPs and VEGF. We demonstrate the presence of soluble VE-cadherin in the sera of mRCC patients (n = 131) which level at baseline, is higher than in a healthy donor group (n = 96). Analysis of sVE level after 4 weeks of treatment showed that a decrease in sVE level discriminates the responders vs. non-responders to sunitinib, but not bevacizumab.

Conclusions

These data highlight the interest for the sVE bioassay in future follow-up of cancer patients treated with targeted therapies such as tyrosine-kinase inhibitors.

Urinary RNA-based biomarkers for prostate cancer detection

Prostate cancer (PCa) is the commonest malignancy in the male population worldwide. Serum prostate specific antigen (PSA) test is the most important biomarker for the detection, follow-up and therapeutic monitoring of PCa. Defects in PSA specificity have elicited research for new biomarkers to improve early diagnosis and avoid false-positive results. This review evaluates urinary RNA-based biomarkers. Urine is a versatile body fluid for non-invasive biomarker detection in case of urological malignancies. The importance of RNA-based biomarkers has been demonstrated by the current use of PCA3, a long non coding RNA biomarker already approved by the Food and Drugs Administration. Through the years, other urinary RNA biomarkers have been evaluated, including the well-known TMPRSS2:ERG transcript, as well as many messenger RNAs, long non coding RNAs and micro-RNA. Validation of a specific urinary RNA-based marker or an algorithm of different biomarkers levels as diagnostic markers for PCa could be useful to avoid unnecessary prostate biopsies.

Secreted miR-210-3p as non-invasive biomarker in clear cell renal cell carcinoma

The most common subtype of renal cell carcinoma (RCC) is clear cell RCC (ccRCC). It accounts for 70-80% of all renal malignancies representing the third most common urological cancer after prostate and bladder cancer. The identification of non-invasive biomarkers for the diagnosis and responsiveness to therapy of ccRCC may represent a relevant step-forward in ccRCC management. The aim of this study is to evaluate whether specific miRNAs deregulated in ccRCC tissues present altered levels also in urine specimens. To this end we first assessed that miR-21-5p, miR-210-3p and miR-221-3p resulted upregulated in ccRCC fresh frozen tissues compared to matched normal counterparts. Next, we evidenced that miR-210-3p resulted significantly up-regulated in 38 urine specimens collected from two independent cohorts of ccRCC patients at the time of surgery compared to healthy donors samples. Of note, miR-210-3p levels resulted significantly reduced in follow-up samples. These results point to miR-210-3p as a potential non-invasive biomarker useful not only for diagnosis but also for the assessment of complete resection or response to treatment in ccRCC management.

Functional analysis of fatty acid binding protein 7 and its effect on fatty acid of renal cell carcinoma cell lines

Background

Renal cell carcinomas (RCCs) overexpress fatty acid binding protein 7 (FABP7). We chose to study the TUHR14TKB cell line, because it expresses higher levels of FABP7 than other cell lines derived from renal carcinomas (OS-RC-2, 786-O, 769-P, Caki-1, and ACHN).

Methods

FABP7 expression was detected using western blotting and real-time PCR. Cell proliferation was determined using an MTS assay and by directly by counting cells. The cell cycle was assayed using flow cytometry. Cell migration was assayed using wound-healing assays. An FABP7 expression vector was used to transfect RCC cell lines.

Results

The levels of FABP7 expressed by TUHR14TKB cells and their doubling times decreased during passage. High-passage TUHR14TKB cells comprised fewer G0/G1-phase and more S-phase cells than low-passage cells. Cell proliferation differed among subclones isolated from cultures of low-passage TUHR14TKB cells. The proliferation of TUHR14TKB cells decreased when FABP7 was overexpressed, and the cell migration property of TUHR14TKB cells were decreased when FABP7 was overexpressed. High concentrations of docosatetraenoic acid and eicosapentaenoic acid accumulated in TUHR14TKB cells that overexpressed FABP7, and docosatetraenoic acid enhanced cell proliferation.

Conclusions

The TUHR14TKB cell line represents a heterogeneous population that does not express FABP7 when it rapidly proliferates. The differences in FABP7 function between RCC cell lines suggests that FABP7 affects cell proliferation depending on cell phenotype.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3184-x) contains supplementary material, which is available to authorized users.

Mutations in the Mitochondrial ND1 Gene Are Associated with Postoperative Prognosis of Localized Renal Cell Carcinoma

We analyzed mutations in the mitochondrial ND1 gene to determine their association with clinicopathological parameters and postoperative recurrence of renal cell carcinoma (RCC) in Japanese patients. Among 62 RCC cases for which tumor pathology was confirmed by histopathology, ND1 sequencing revealed the presence of 30 mutation sites in 19 cases. Most mutations were heteroplasmic, with 16 of 19 cases harboring one or more heteroplasmic sites. Additionally, 12 sites had amino acid mutations, which were frequent in 10 of the cases. The 5-year recurrence-free survival (RFS) rate was significantly worse in patients with tumors >40 mm in diameter (p = 0.0091), pathological T (pT) stage ≥3 (p = 0.0122), Fuhrman nuclear atypia grade ≥III (p = 0.0070), and ND1 mutations (p = 0.0006). Multivariate analysis using these factors revealed that mutations in ND1 were significantly associated with the 5-year RFS rate (p = 0.0044). These results suggest a strong correlation between the presence of ND1 mutations in cancer tissue and postoperative recurrence of localized RCC in Japanese patients.

The proteomic landscape of renal tumors

INTRODUCTION

Renal cell carcinoma (RCC) is the most fatal of the common urologic cancers, with approximately 35% of patients dying within 5 years following diagnosis. Therefore, there is a need for non-invasive markers that are capable of detecting and determining the severity of small renal masses at an early stage in order to tailor treatment and follow-up. Proteomic studies have proved to be very useful in the study of tumors. Areas covered: In this review, we will detail the current knowledge obtained by the different proteomic approaches, focusing on MS-based strategies, used to investigate RCC biology in order to identify diagnostic, prognostic and predictive biomarkers on tissue, cultured cells and biological fluids. Expert commentary: Currently, no reliable biomarkers or targets for RCC have been translated into the clinical setting. Moreover, despite the efforts of proteomics and other -omics disciplines, only a small number of them have been observed as shared targets between the different analytical platforms and biological specimens. The difficulty to define a specific molecular pattern for RCC and its subtypes highlights a peculiar profile and a heterogeneity that must be taken into account in future studies.

Review of renal cell carcinoma and its common subtypes in radiology

Representing 2%-3% of adult cancers, renal cell carcinoma (RCC) accounts for 90% of renal malignancies and is the most lethal neoplasm of the urologic system. Over the last 65 years, the incidence of RCC has increased at a rate of 2% per year. The increased incidence is at least partly due to improved tumor detection secondary to greater availability of high-resolution cross-sectional imaging modalities over the last few decades. Most RCCs are asymptomatic at discovery and are detected as unexpected findings on imaging performed for unrelated clinical indications. The 2004 World Health Organization Classification of adult renal tumors stratifies RCC into several distinct histologic subtypes of which clear cell, papillary and chromophobe tumors account for 70%, 10%-15%, and 5%, respectively. Knowledge of the RCC subtype is important because the various subtypes are associated with different biologic behavior, prognosis and treatment options. Furthermore, the common RCC subtypes can often be discriminated non-invasively based on gross morphologic imaging appearances, signal intensity on T2-weighted magnetic resonance images, and the degree of tumor enhancement on dynamic contrast-enhanced computed tomography or magnetic resonance imaging examinations. In this article, we review the incidence and survival data, risk factors, clinical and biochemical findings, imaging findings, staging, differential diagnosis, management options and post-treatment follow-up of RCC, with attention focused on the common subtypes.

From Smallpox to Big Data: The Next 100 Years of Epidemiologic Methods

For more than a century, epidemiology has seen major shifts in both focus and methodology. Taking into consideration the explosion of "big data," the advent of more sophisticated data collection and analytical tools, and the increased interest in evidence-based solutions, we present a framework that summarizes 3 fundamental domains of epidemiologic methods that are relevant for the understanding of both historical contributions and future directions in public health. First, the manner in which populations and their follow-up are defined is expanding, with greater interest in online populations whose definition does not fit the usual classification by person, place, and time. Second, traditional data collection methods, such as population-based surveillance and individual interviews, have been supplemented with advances in measurement. From biomarkers to mobile health, innovations in the measurement of exposures and diseases enable refined accuracy of data collection. Lastly, the comparison of populations is at the heart of epidemiologic methodology. Risk factor epidemiology, prediction methods, and causal inference strategies are areas in which the field is continuing to make significant contributions to public health. The framework presented herein articulates the multifaceted ways in which epidemiologic methods make such contributions and can continue to do so as we embark upon the next 100 years.

Tumor size, stage and grade alterations of urinary peptidome in RCC

Background

Several promising biomarkers have been found for RCC, but none of them has been used in clinical practice for predicting tumour progression. The most widely used features for predicting tumour aggressiveness still remain the cancer stage, size and grade. Therefore, the aim of our study is to investigate the urinary peptidome to search and identify peptides whose concentrations in urine are linked to tumour growth measure and clinical data.

Methods

A proteomic approach applied to ccRCC urinary peptidome (n = 117) based on prefractionation with activated magnetic beads followed by MALDI-TOF profiling was used. A systematic correlation study was performed on urinary peptide profiles obtained from MS analysis. Peptide identity was obtained by LC–ESI–MS/MS.

Results

Fifteen, twenty-six and five peptides showed a statistically significant alteration of their urinary concentration according to tumour size, pT and grade, respectively. Furthermore, 15 and 9 signals were observed to have urinary levels statistically modified in patients at different pT or grade values, even at very early stages. Among them, C1RL, A1AGx, ZAG2G, PGBM, MMP23, GP162, ADA19, G3P, RSPH3, DREB, NOTC2 SAFB2 and CC168 were identified.

Conclusions

We identified several peptides whose urinary abundance varied according to tumour size, stage and grade. Among them, several play a possible role in tumorigenesis, progression and aggressiveness. These results could be a useful starting point for future studies aimed at verifying their possible use in the managements of RCC patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-015-0693-8) contains supplementary material, which is available to authorized users.