Prognostic factors and selection for clinical studies of patients with kidney cancer

CD44 Expression in Clear Cell Renal Cell Carcinoma (ccRCC) Correlates with Tumor Grade and Patient Survival and Is Affected by Gene Methylation

Clear cell RCC (ccRCC) represents the most common type of kidney cancer, with surgery being the only potential curative treatment. Almost one-third of ccRCC patients relapse either locally or as cases of distant metastases. Several biomarkers have been employed in order to separate ccRCC patients with better prognosis or to predict treatment outcomes, with limited results. CD44 is a membrane glycoprotein with multiple roles in normal development but also cancer. Recently, the CD44 standard isoform has been implicated in tumor progression and the metastasis cascade through microenvironment interactions. Here, through CD44 immunohistochemical staining of ccRCC patient samples and TCGA data analysis, we sought to elucidate the expression patterns (mRNA and protein) of CD44 in clear cell RCC and correlate its expression with clinicopathological parameters. We were able to show that CD44 expression presents a positive association with tumor grade and overall survival, predicting a worse patient outcome in ccRCC. In addition, our data indicate that the CD44 mRNA upregulation can be attributed to reduced gene methylation, implicating epigenetic gene regulation in ccRCC development and progression.

Incremental value of radiomics with machine learning to the existing prognostic models for predicting outcome in renal cell carcinoma

Purpose

To systematically evaluate the potential of radiomics coupled with machine-learning algorithms to improve the predictive power for overall survival (OS) of renal cell carcinoma (RCC).

Methods

A total of 689 RCC patients (281 in the training cohort, 225 in the validation cohort 1 and 183 in the validation cohort 2) who underwent preoperative contrast-enhanced CT and surgical treatment were recruited from three independent databases and one institution. 851 radiomics features were screened using machine-learning algorithm, including Random Forest and Lasso-COX Regression, to establish radiomics signature. The clinical and radiomics nomogram were built by multivariate COX regression. The models were further assessed by Time-dependent receiver operator characteristic, concordance index, calibration curve, clinical impact curve and decision curve analysis.

Result

The radiomics signature comprised 11 prognosis-related features and was significantly correlated with OS in the training and two validation cohorts (Hazard Ratios: 2.718 (2.246,3.291)). Based on radiomics signature, WHOISUP, SSIGN, TNM Stage and clinical score, the radiomics nomogram has been developed. Compared with the existing prognostic models, the AUCs of 5 years OS prediction of the radiomics nomogram were superior to the TNM, WHOISUP and SSIGN model in the training cohort (0.841 vs 0.734, 0.707, 0.644) and validation cohort2 (0.917 vs 0.707, 0.773, 0.771). Stratification analysis suggested that the sensitivity of some drugs and pathways in cancer were observed different for RCC patients with high-and low-radiomics scores.

Conclusion

This study showed the application of contrast-enhanced CT-based radiomics in RCC patients, creating novel radiomics nomogram that could be used to predict OS. Radiomics provided incremental prognostic value to the existing models and significantly improved the predictive power. The radiomics nomogram might be helpful for clinicians to evaluate the benefit of surgery or adjuvant therapy and make individualized therapeutic regimens for patients with renal cell carcinoma.

Neutrophil-to-Lymphocyte Ratio Predicts Cancer Outcome in Locally Advanced Clear Renal Cell Carcinoma

BACKGROUND

To evaluate the association of neutrophil-to-lymphocyte ratio (NLR) with recurrence-free survival (RFS) and overall survival (OS) in patients with locally advanced nonmetastatic clear cell renal cell carcinoma (ccRCC) undergoing radical nephrectomy.

MATERIAL AND METHODS

We retrospectively identified 880 nephrectomies performed between January 2009 and December 2016 in a single center, reviewed data from 478 radical nephrectomies for kidney tumors and identified 187 patients with locally advanced nonmetastatic ccRCC (pT3-T4 N0M0). NLR was obtained preoperatively and calculated by dividing absolute neutrophil count by absolute lymphocyte count. OS and RFS were evaluated by the Kaplan-Meier method. Cox proportional-hazards regression models were used to evaluate predictors of RFS and OS.

RESULTS

Among 187 patients with ccRCC (mean age 63.4 ± 11.5 years; 118 [63.1%] male), the median follow-up was 48.7 months. On univariate analysis, in patients with Fuhrman nuclear grade of differentiation 3-4, the median time to recurrence was significantly shorter with NLR ≥ 4 than < 4 (24 vs. 55 months, P = .045). On multivariable analysis adjusted for NLR ≥ 4, among all variables analyzed (NLR, microvascular invasion, sarcomatoid differentiation, tumor size and body mass index), only nuclear grade of differentiation was an independent predictor of recurrence (hazard ratio 2.18; 95% confidence interval 1.07-4.92, P = .03). The 3-year OS had no statistically significant difference between patients with NLR ≥ 4 or < 4.

CONCLUSION

For patients with locally advanced, nonmetastatic ccRCC, RFS was reduced with high nuclear grade of differentiation and high preoperative NLR. These findings suggest an association between higher NLR and worse outcomes in locally advanced ccRCC.

Modeling Neoplastic Growth in Renal Cell Carcinoma and Polycystic Kidney Disease

Renal cell carcinoma (RCC) and autosomal dominant polycystic kidney disease (ADPKD) share several characteristics, including neoplastic cell growth, kidney cysts, and limited therapeutics. As well, both exhibit impaired vasculature and compensatory VEGF activation of angiogenesis. The PI3K/AKT/mTOR and Ras/Raf/ERK pathways play important roles in regulating cystic and tumor cell proliferation and growth. Both RCC and ADPKD result in hypoxia, where HIF-α signaling is activated in response to oxygen deprivation. Primary cilia and altered cell metabolism may play a role in disease progression. Non-coding RNAs may regulate RCC carcinogenesis and ADPKD through their varied effects. Drosophila exhibits remarkable conservation of the pathways involved in RCC and ADPKD. Here, we review the progress towards understanding disease mechanisms, partially overlapping cellular and molecular dysfunctions in RCC and ADPKD and reflect on the potential for the agile Drosophila genetic model to accelerate discovery science, address unresolved mechanistic aspects of these diseases, and perform rapid pharmacological screens.

Roles of microRNA-186 and vascular endothelial growth factor in hepatocellular carcinoma complicated with portal vein tumor thrombus

The present study aims to investigate the role and underlying mechanism of microRNA (miR)-186 in patients with hepatocellular carcinoma (HCC) complicated with portal vein tumor thrombus. Blood samples from 29 HCC patients with portal vein tumor thrombus were collected between January 2014 and September 2015 in Huai'an First People's Hospital, while blood from 36 HCC patients without vein tumor thrombus was also collected in the same period. In addition, tumor thrombus specimens were collected from the HCC patients with portal vein tumor thrombus, and peritumoral tissues of the tumor thrombus were used as the control. Reverse transcription-quantitative polymerase chain reaction, ELISA and western blot analyses were applied to detect vascular endothelial growth factor (VEGF) expression at the mRNA and protein levels. Bioinformatics prediction was used to predict the target of miR-186, and then miR-186 expression was detected. Furthermore, dual-luciferase reporter assay was used to validate whether miR-186 directly targeted VEGF. Following transfection with agomiR-186, the expression levels of miR-186 and VEGF were detected, while MTT assay was used to detect EA.hy926 cell proliferation subsequent to small interfering RNA (siRNA) silencing. The results identified that VEGF was significantly increased in the tumor thrombus and blood samples of HCC patients with vein tumor thrombus at the mRNA and protein levels, while miR-186 expression was significantly decreased (P<0.05). Following silencing VEGF by siRNA transfection, the proliferation of EA.hy926 cells was inhibited. In addition, VEGF expression was significantly decreased and cell proliferation was reduced when upregulating miR-186. Dual-luciferase reporter assay demonstrated that miR-186 regulated VEGF expression through complementary binding to 3'-untranslated region. In conclusion, VEGF was significantly increased in tumor thrombus and blood samples from HCC patients with vein tumor thrombus, which may be associated with the downregulation of miR-186. Thus, miR-186 may promote the development and progression of vein tumor thrombus in HCC.

Association of Abl interactor 2, ABI2, with platelet/lymphocyte ratio in patients with renal cell carcinoma: A pilot study

There are many unknown aspects of the pathogenesis of renal cell carcinoma (RCC). The aim of the current study was to define new RCC-related genes and measure their associations with RCC and clinical parameters, especially platelet/lymphocyte ratio which may be an independent predictor of prognosis in patients with RCC and other forms of cancer. Via in silico analysis upon RCC-specific deleted genes in chromosome 3, four possible ceRNAs (ATXN3, ABI2, GOLGB1 and SMAD2) were identified. Then, the expression levels of these genes in tumour and adjacent healthy kidney tissues of 19 RCC patients were determined by real-time PCR. ATXN3 and GOLGB1 gene expression levels increased but ABI2 gene expression level decreased in tumour kidney tissues when compared to normal ones. ATXN3, ABI2 and GOLGB1 gene expression levels were significantly higher in Fuhrman grade 4 than other grades (P < .001). ABI2 gene expression levels were significantly associated with higher platelet/lymphocyte ratio of the patients with RCC (P < .05). ATXN3, ABI2 and GOLGB1 may predict higher RCC grades. Also, ABI2 may regulate platelet/lymphocyte ratio which may be an independent predictor of RCC and other forms of cancer.

Construction and validation of a seven-gene signature for predicting overall survival in patients with kidney renal clear cell carcinoma via an integrated bioinformatics analysis

Kidney renal clear cell carcinoma (KIRC) remains a significant challenge worldwide because of its poor prognosis and high mortality rate, and accurate prognostic gene signatures are urgently required for individual therapy. This study aimed to construct and validate a seven-gene signature for predicting overall survival (OS) in patients with KIRC. The mRNA expression profile and clinical data of patients with KIRC were obtained from The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC). Prognosis-associated genes were identified, and a prognostic gene signature was constructed. Then, the prognostic efficiency of the gene signature was assessed. The results obtained using data from the TCGA were validated using those from the ICGC and other online databases. Gene set enrichment analyses (GSEA) were performed to explore potential molecular mechanisms. A seven-gene signature (PODXL, SLC16A12, ZIC2, ATP2B3, KRT75, C20orf141, and CHGA) was constructed, and it was found to be effective in classifying KIRC patients into high- and low-risk groups, with significantly different survival based on the TCGA and ICGC validation data set. Cox regression analysis revealed that the seven-gene signature had an independent prognostic value. Then, we established a nomogram, including the seven-gene signature, which had a significant clinical net benefit. Interestingly, the seven-gene signature had a good performance in distinguishing KIRC from normal tissues. GSEA revealed that several oncological signatures and GO terms were enriched. This study developed a novel seven-gene signature and nomogram for predicting the OS of patients with KIRC, which may be helpful for clinicians in establishing individualized treatments.

New Preoperative Nomogram Using the Centrality Index to Predict High Nuclear Grade Clear Cell Renal Carcinoma

Objective

Nuclear grading is an independent prognosis factor of clear-cell renal cell carcinoma (ccRCC). A non-invasive preoperative predictive WHO/International Society of Urologic Pathology (WHO/ISUP) grading of ccRCC model is needed for clinical use. The anatomical complexity scoring system can span a variety of image modalities. The Centrality index (CI) is a quantitatively anatomical score commonly used for renal tumors. The purpose of this study was to develop a simple model to predict WHO/ISUP grading based on CI.

Materials and methods

The data in this study were from 248 ccRCC patients from five hospitals. We developed three predictive models using training data from 167 patients: a CI-only model, a valuable clinical parameter model and a fusion model of CI with valuable clinical parameters. We compared and evaluated the three models by discrimination, clinical usefulness and calibration, then tested them in a set of validation data from 81 patients.

Results

The fusion model consisting of CI and tumor size (valuable clinical parameter) had an area under the curve (AUC) of 0.82. In the validation set, the AUC was 0.85. The decision curve showed that the model had a good net benefit between the threshold probabilities of 5–80%. And the calibration curve showed good calibration in the training set and validation set.

Conclusion

This study confirms that CI is associated with the WHO/ISUP grade of ccRCC, and the possibility that a bivariate model incorporating tumor size may help urologist’s evaluation patients’ prognostic.

Development of a Highly Sensitive Technique for Capturing Renal Cell Cancer Circulating Tumor Cells

Purpose: Liquid biopsy is becoming increasingly important as a guide for selecting new drugs and determining their efficacy. In urological cancer, serum markers for renal cell and urothelial cancers has made the development of liquid biopsy for these cancers strongly desirable. Liquid biopsy is less invasive than conventional tissue biopsy is, enabling frequent biopsies and, therefore, is considered effective for monitoring the treatment course. Circulating tumor cells (CTCs) are a representative liquid biopsy specimen. In the present study, we focused on developing our novel technology for capturing renal cell cancer (RCC)-CTCs using an anti-G250 antibody combined with new devices. Basic experiments of our technology showed that it was possible to detect RCC-CTC with a fairly high accuracy of about 95%. Also, RCC-CTC was identified in the peripheral blood of actual RCC patients. Additionally, during the treatment course of the RCC patient, change in the number of RCC-CTC was confirmed in one case. We believe that the technology we developed will be useful for determining the treatment efficacy and drug selection for the treatment of renal cell cancer (RCC). In order to solve issues such as thresholds setting of this technology, large-scale clinical trials are expected.

A long non-coding RNA signature to improve prognostic prediction in clear cell renal cell carcinoma

BACKGROUND

Accumulating research reports have indicated that long non-coding RNAs (lncRNAs) are abnormally expressed in many types of cancers. However, few lncRNA signatures for predicting cancer prognosis have been established. Our goal is to establish a lncRNA signature for predicting the prognosis of clear cell renal cell carcinoma (ccRCC).

METHODS

We downloaded KIRC lncRNA FPKM (Fragments Per Kilobase of transcript per Million Fragments) standardized expression data from The Cancer Genome Atlas (TCGA) by using the TANRIC tool. We established an 11-lncRNA signature that was clearly linked to the overall survival (OS) rates in the training and test sets.

RESULTS

The training set was divided into the high-risk and low-risk subgroups, between which the OS was disparate (HR = 1.51, 95%CI = 1.39-1.64, P < 0.0001). The accuracy of the 11-lncRNA signature for predicting prognosis was confirmed in the test set. Further analysis revealed that the prognostic value of this signature was independent of the neoplasm grade and TNM stage. Gene set enrichment analysis (GSEA) was performed, and a summary of 4 gene sets related to canonical pathway, biological process, molecular function and cellular component was obtained. We demonstrated the biological function of these lncRNAs in ccRCC cell lines and found that LINC00488 and HOTTIP promoted tumour proliferation and inhibited apoptosis. However, LINC-PINT had the opposite effect.

CONCLUSIONS

The establishment of the 11-lncRNA signature indicated the underlying biochemical functional roles of the selected lncRNAs in ccRCC. Our results may provide a reliable theoretical basis for clinical evaluation of ccRCC prognosis.

Identification of a universal 6-lncRNA prognostic signature for three pathologic subtypes of renal cell carcinoma

Renal cell carcinoma (RCC) is the most common adult renal epithelial cancer susceptible to metastasis and patients with irresectable RCC always have a poor prognosis. Long noncoding RNAs (lncRNAs) have recently been documented as having critical roles in the etiology of RCC. Nevertheless, the prognostic significance of lncRNA-based signature for outcome prediction in patients with RCC has not been well investigated. Therefore, it is essential to identify a lncRNA-based signature for predicting RCC prognosis. In the current study, we comprehensively analyzed the RNA sequencing data of the three main pathological subtypes of RCC (kidney renal clear cell carcinoma [KIRC], kidney renal papillary cell carcinoma [KIRP], and kidney chromophobe carcinoma [KICH]) from The Cancer Genome Atlas (TCGA) database, and identified a 6-lncRNA prognostic signature with the help of a step-wise multivariate Cox regression model. The 6-lncRNA signature stratified the patients into low- and high-risk groups with significantly different prognosis. Multivariate Cox regression analysis showed that predictive value of the 6-lncRNA signature was independent of other clinical or pathological factors in the entire cohort and in each cohort of RCC subtypes. In addition, the three independent prognostic clinical factors (including age, pathologic stage III, and stage IV) was also stratified into low- and high-risk groups basis on the risk score, and the stratification analyses demonstrated that the high-risk score was a poor prognostic factor. In conclusion, these findings indicate that the 6-lncRNA signature is a novel prognostic biomarker for all three subtypes of RCC, and can increase the accuracy of predicting overall survival.

Expression and role of VEGFA and miR-381 in portal vein tumor thrombi in patients with hepatocellular carcinoma

The aim of the present study was to examine the expression and role of vascular endothelial growth factor A (VEGFA) and microRNA (miRNA or miR)-381 in tumor thrombi from patients with hepatocellular carcinoma and portal vein tumor thrombus (PVTT). Tumor thrombi and adjacent paired tissues were collected from 39 patients with hepatocellular carcinoma with PVTT. VEGFA expression levels were assessed using reverse transcription-quantitative polymerase chain reaction and western blotting. miRNAs that may regulate VEGFA expression were predicted using bioinformatics analysis and confirmed via a dual luciferase reporter assay. The effects of VEGFA and its upstream miRNA on proliferation of the proliferation of EAhy926 human venous endothelial cells were analyzed using an MTT assay. Compared with the paired adjacent tissues, VEGFA was significantly upregulated at both the mRNA and protein level in tumor thrombi (P<0.05). VEGFA was predicted to be a target of miR-381 and this was confirmed experimentally. miR-381 expression was significantly downregulated in tumor thrombi from patients with PVTT compared with paired adjacent tissues (P<0.05). In addition, transfection with antagomirs against miR-381 or short interfering RNA against VEGFA significantly inhibited EAhy926 cell proliferation (P<0.05). In conclusion, the results of the present study indicate that VEGFA is upregulated in tumor thrombi whereas miR-381 is downregulated. VEGFA is regulated by miR-381 and both may be associated with the development of PVTT.

Combined cell surface carbonic anhydrase 9 and CD147 antigens enable high-efficiency capture of circulating tumor cells in clear cell renal cell carcinoma patients

Circulating tumor cells (CTCs) have emerged as promising tools for noninvasive cancer detection and prognosis. Most conventional approaches for capturing CTCs use an EpCAM-based enrichment strategy, which does not work well in cancers that show low or no expression of EpCAM, such as renal cell carcinoma (RCC). In this study, we developed a new set of cell surface markers including CA9 and CD147 as alternative CTC-capture antigens specifically designed for RCC patients. We showed that the expression of both CA9 and CD147 was prevalent in a RCC patient cohort (n=70) by immunohistochemical analysis, with both molecules in combination covering 97.1% of cases. The NanoVelcro platform combined with CA9-/CD147-capture antibodies demonstrated significantly higher efficiency for capturing both CTC-mimicking renal cancer cells and RCC CTCs in peripheral blood, compared to the conventional EpCAM-based method. Using immunofluorescence cytological validation at the single-cell level, we were able to identify bona fide CTCs in RCC patient blood following the well-accepted criteria in our CTC-capture system. We further demonstrated a significant association of CTC numbers as well as the CTC expression status of Vimentin, a mesenchymal marker, with disease progression, including pathologic features and clinical staging. These results provide new insights into developing novel, effective targets/approaches for capturing CTCs, making CTCs a valuable tool for improved cancer detection, prognosis and treatment in RCC.

Tissue and urinary KIM-1 relate to tumor characteristics in patients with clear renal cell carcinoma

The objective of this prospective follow-up trial was to ascertain whether the urinary kidney injury molecule-1 (uKIM-1) associates with tumor tissue (tKIM-1) expression and with the pathological characteristics of clear renal cell carcinoma (cRCC) in radically nephrectomized (RN) and/or in partially nephrectomized (PN) patients with cRCC, pre- and postoperatively. This clinical study included 40 patients subjected to RN/PN (cRCC group) and 30 healthy volunteers (control group). Urinary KIM-1 was determined by ELISA TIM-1/KIM-1 kit and normalized by urinary creatinine. Immunohistochemical staining (monoclonal anti-human anti-TIM-1/KIM-1/HAVCR antibody) was used for semiquantitative analysis of the tKIM-1 expression and expressed as a score (% KIM-1 positively stained tubules). Both markers were interpreted in terms of the tumor characteristics comprising tumor size, Fuhrman grade, pathological (pT) stage, tumor/nodes/metastasis (TNM) stage, lymphovascular invasion and type of surgery RN/PN. Preoperative uKIM-1 was significantly higher in the cRCC group compared to controls, such as uKIM-1 was statistically higher in RN than in PN patients. Postoperatively, uKIM-1 decreased to control values. Expression of tKIM-1 was documented in all nephrectomized patients. Significant associations were achieved between uKIM-1 and tKIM-1 and with considered tumor characteristics, especially with tumor size and grade. Based on the accomplished associations, we found uKIM-1 as a highly sensitive marker for cRCC diagnosis. The clinical trial registration number: 1110-2012.

Prognostic value of granulocyte colony-stimulating factor in patients with non-metastatic clear cell renal cell carcinoma

Granulocyte colony-stimulating factor is a well-known cytokine to stimulate inflammatory cells. We sought to investigate the prognostic value of its expression in patients with non-metastatic clear cell renal cell carcinoma. Enrolled in this study were 228 eligible patients treated with curative nephrectomy for clear cell renal cell carcinoma during 2008. Granulocyte colony-stimulating factor expression was detected by immunohistochemistry in patient specimens, and was divided into three groups according to the distribution of its immunohistochemistry score. Subgroup analyses were performed to evaluate its risk stratification ability. Cox regression models were applied to analyze the impact of prognostic factors. We found that high granulocyte colony-stimulating factor expression was associated with diminished recurrence-free survival (P<0.001). Its expression had stronger stratification ability in late disease patients, and was further identified as an independent prognosticator for recurrence-free survival. Moreover, nomogram based on granulocyte colony-stimulating factor expression presented a better prognostic ability compared with current prognostic systems (the concordance index = 0.874). To conclude, intratumoal granulocyte colony-stimulating factor expression could be a potential prognosticator for recurrence-free survival in non-metastatic clear cell renal cell carcinoma patients. Incorporating its expression into other pathologic factors provided a finer individual model for non-metastatic clear cell renal cell patients.

Role of Contrast Enhancement and Corrected Attenuation Values of Renal Tumors in Predicting Renal Cell Carcinoma (RCC) Subtypes: Protocol for a Triphasic Multi-Slice Computed Tomography (CT) Procedure

BACKGROUND

To distinguish RCC subtypes based on contrast enhancement features of CT images.

MATERIAL/METHODS

In total, 59 lesions from 57 patients were included. All patients underwent multi-slice CT imaging with a triphasic protocol, which included non-contrast, corticomedullary, nephrographic and urographic phases. Contrast enhancement features of renal masses were evaluated in terms of CT attenuation values (AV) and differences in contrast density; the aorta or renal parenchyma were evaluated based on corrected or relative values.

RESULTS

Clear cell RCC (ccRCC) showed more intense contrast enhancement than other RCC subtypes. When differentiating ccRCC from other RCC subtypes, a cut-off AV of 86-89 HU, aorta-based corrected AV of 89-95 HU and renal parenchyma-based corrected AV of 87-95 HU showed a diagnostic accuracy of 81-86%, 86-88% and 74-78%, respectively, in the corticomedullary phase. Furthermore, a cutoff of 2.42-2.72 for the relative contrast enhancement ratio, a cutoff of 2.59-2.74 for the aorta-based corrected relative contrast enhancement ratio and a cutoff of 2.63-2.76 for the renal parenchyma-based attenuation ratio showed a diagnostic accuracy of 83-88%, 88-90% and 81%, respectively.

CONCLUSIONS

The most reliable parameters for differentiating ccRCC from other RCC subtypes are aorta-based corrected AV and aorta-based corrected relative contrast enhancement values in the corticomedullary phase.

Recurrence in Localized Renal Cell Carcinoma: a Systematic Review of Contemporary Data

PURPOSE OF REVIEW

Patients with localized renal cell carcinoma (RCC) are at risk of recurrence. The purpose of this review was to characterize the literature on recurrence rates and risk factors after diagnosis of localized RCC.

RECENT FINDINGS

Our search revealed that existing data examining the prevalence of recurrence rates predominantly originates from cohorts of patients diagnosed and treated in the 1980s to 1990s, and may therefore not be as useful for counseling for current patients today. Many nomograms including the Cindolo Recurrence Risk Formula, the University of California-Los Angeles (UCLA) Integrated Scoring System (UISS), the SSIGN score, the Kattan nomogram, and the Karakiewicz nomogram have shown value in identifying patients at higher risk for recurrence. Biomarkers and gene assays have shown promise in augmenting the predictive accuracy of some of the aforementioned predictive models, especially when multiple gene markers are used in combination. However, more work is needed in not only developing a model but also validating it in other settings prior to clinical use. Adjuvant therapy is a promising new treatment strategy for patients with high-risk disease. Importantly, too many surveillance strategies exist. This may stem from the lack of a consensus in the urological community in how to follow these patients, as well as the variable guideline recommendations. In conclusion, contemporary recurrence rates are needed. Recurrence risk prediction models should be developed based on a series of more contemporary patients, and externally validated prior to routine clinical practice. Surveillance strategies following treatment of localized RCC need to be identified and standardized. Finally, there is a trend toward personalizing surveillance regimens to more appropriately screen patients at higher risk of recurrence.

Pre-treatment neutrophil-to-lymphocyte ratio predicts tumor pathology in newly diagnosed renal tumors

PURPOSE

The neutrophil-to-lymphocyte ratio (NLR) predicts adverse outcomes after surgical treatment for clear cell renal cell carcinoma (ccRCC). However, its ability to distinguish aggressive from indolent renal tumors remains unknown. We therefore evaluated the association between NLR and pathologic outcomes at nephrectomy.

METHODS

From 1995 to 2008, 2402 patients underwent radical or partial nephrectomy for localized renal tumors. Of these, 2039 had an NLR within 90 days prior to surgery. Comparisons of NLR by tumor size, histologic subtype, and nuclear grade were evaluated.

RESULTS

Benign renal masses had a significantly lower NLR than malignant tumors (median 2.92 vs. 3.12; p = 0.037) with the greatest difference noted among renal lesions >7 cm (median 2.79 vs. 3.87; p < 0.001). There was a significant difference in NLR among RCC subtypes (p = 0.002), with cystic ccRCC demonstrating the lowest (median 2.48) and collecting duct RCC the highest NLR (median 5.99). Moreover, there was a significant increase in NLR with larger tumor size and greater nuclear grade (p < 0.001). Specifically, in patients with ccRCC, an incremental increase in tumor size (≤4 cm = 2.80, >4 but ≤7 cm = 3.09 and >7 cm = 3.95) and nuclear grade (G1 = 2.68, G2 = 2.87, G3 = 3.48, and G4 = 5.18) was associated with greater NLR (p < 0.001).

CONCLUSIONS

An elevated NLR is associated with RCC pathology, higher-grade tumors, and more aggressive histologic subtypes at the time of nephrectomy. Therefore, NLR appears to be a preoperative marker of biologically aggressive RCC and may be useful in predicting malignancy and guiding management among patients with suspicious renal tumors.

Genomic DNA Hypomethylation and Risk of Renal Cell Carcinoma: A Case-Control Study

PURPOSE

Genomic DNA hypomethylation is a hallmark of most cancer genomes, promoting genomic instability and cell transformation. In the present study, we sought to determine whether global DNA methylation in peripheral blood is associated with risk of renal cell carcinoma (RCC).

EXPERIMENTAL DESIGN

A retrospective case-control study consisting of 889 RCC cases and an equal number of age, gender, and ethnicity-matched controls was applied. Global DNA methylation was measured as 5-mC% content. Logistic regression was used to estimate odds ratio (OR) and 95% confidence interval (CI) for the association between DNA methylation level and the risk of RCC.

RESULTS

The median 5-mC% was significantly lower in cases than in healthy controls (P< 0.001). In multivariate logistic regression analysis, individuals in the lowest tertile (T1) of 5-mC% had higher risk of RCC with OR of 1.40 (95% CI, 1.06-1.84), compared with individuals in the highest tertile (T3;Pfor trend= 0.02). When stratified by RCC risk factors, associations between hypomethylation and increased RCC risk appeared to be stronger among males (OR, 1.61;Pfor trend= 0.01), younger age (OR, 1.47;Pfor trend= 0.03), never smokers (OR, 1.55;Pfor trend= 0.02), family history of other cancer (OR, 1.64;Pfor trend= 1.22E-03), and late stage (OR, 2.06,Pfor trend= 4.98E-04). Additionally, we observed significant interaction between gender and 5-mC% in elevating RCC risk (Pfor interaction= 0.03).

CONCLUSIONS

Our findings suggest an association between global DNA hypomethylation and RCC risk. To establish global DNA hypomethylation as a risk factor for RCC, future prospective studies are warranted. This study may provide further understanding of the etiology of RCC tumorigenesis.

TRIM8 anti-proliferative action against chemo-resistant renal cell carcinoma

In some tumours, despite a wild-type p53 gene, the p53 pathway is inactivated by alterations in its regulators or by unknown mechanisms, leading to resistance to cytotoxic therapies. Understanding the mechanisms of functional inactivation of wild-type p53 in these tumours may help to define prospective targets for treating cancer by restoring p53 activity.

Recently, we identified TRIM8 as a new p53 modulator, which stabilizes p53 impairing its association with MDM2 and inducing the reduction of cell proliferation.

In this paper we demonstrated that TRIM8 deficit dramatically impairs p53-mediated cellular responses to chemotherapeutic drugs and that TRIM8 is down regulated in patients affected by clear cell Renal Cell Carcinoma (ccRCC), an aggressive drug-resistant cancer showing wild-type p53. These results suggest that down regulation of TRIM8 might be an alternative way to suppress p53 activity in RCC. Interestingly, we show that TRIM8 expression recovery in RCC cell lines renders these cells sensitive to chemotherapeutic treatments following p53 pathway re-activation.

These findings provide the first mechanistic link between TRIM8 and the drug resistance of ccRCC and suggest more generally that TRIM8 could be used as enhancer of the chemotherapy efficacy in cancers where p53 is wild-type and its pathway is defective.

Survival among Black and White patients with renal cell carcinoma in an equal-access health care system

PURPOSE

Unequal access to health care may be a reason for shorter survival among Black patients with renal cell carcinoma (RCC) than among their White counterparts. No studies have investigated survival disparity among RCC patients in an equal-access health care delivery system. This study aimed to examine racial differences in survival among clear cell RCC patients in the Department of Defense's (DoD) Military Health System (MHS), which provides equal access to care to all persons.

METHODS

The study used the DoD's Automated Central Tumor Registry to identify 2056 White patients and 370 Black patients diagnosed with clear cell RCC between 1988 and 2004. The subjects were followed through 2007 with a median follow-up time of 4.8 years. Kaplan-Meier survival curves were compared and a Cox model was used to estimate the hazard ratios (HRs) associated with survival by race.

RESULTS

During follow-up, 1,027 White and 158 Black patients died. The Kaplan-Meier curves showed that Black patients had more favorable overall survival than did White patients (log rank p = 0.031). After adjustment for demographic, tumor, and treatment variables, the Cox model showed no statistically significant racial difference overall (adjusted HR 1.07, 95 % CI 0.90-1.28) or stratified by age, sex or tumor stage. However, among patients who did not undergo surgery, Black patients had poorer survival than White patients.

CONCLUSIONS

The lack of racial difference in survival among RCC patients in the MHS may be related to equal access to health care. Improved access could reduce the survival disparity among RCC patients in the general population.

Preoperative neutrophil-lymphocyte ratio predicts death among patients with localized clear cell renal carcinoma undergoing nephrectomy

OBJECTIVES

The neutrophil-lymphocyte ratio (NLR) is an indicator of the systemic inflammatory response. An increased pretreatment NLR has been associated with adverse outcomes in other malignancies, but its role in localized (M0) clear cell renal cell carcinoma (ccRCC) remains unclear. As such, we evaluated the ability of preoperative NLR to predict oncologic outcomes in patients with M0 ccRCC undergoing radical nephrectomy (RN).

METHODS AND MATERIALS

From 1995 to 2008, 952 patients underwent RN for M0 ccRCC. Of these, 827 (87%) had pretreatment NLR collected within 90 days before RN. Metastasis-free, cancer-specific, and overall survival was estimated using the Kaplan-Meier method and compared using the log-rank test. Multivariate models were used to analyze the association of NLR with clinicopathologic outcomes.

RESULTS

At a median follow-up of 9.3 years, 302, 233, and 436 patients had distant metastasis, death from ccRCC, and all-cause mortality, respectively. Higher NLR was associated with larger tumor size, higher nuclear grade, histologic tumor necrosis, and sarcomatoid differentiation (all, P < 0.001). A NLR ≥ 4.0 was significantly associated with worse 5-year cancer-specific (66% vs. 85%) and overall survival (66% vs. 85%). Finally, after controlling for clinicopathologic features, NLR remained independently associated with risks of death from ccRCC and all-cause mortality (hazard ratio for 1-unit increase: 1.02, P < 0.01).

CONCLUSIONS

Our results suggest that NLR is independently associated with increased risks of cancer-specific and all-cause mortality among patients with M0 ccRCC undergoing RN. Accordingly, NLR, an easily obtained marker of biologically aggressive ccRCC, may be useful in preoperative patient risk stratification.

Identification of high-risk patients with clear cell renal cell carcinoma based on interphase-FISH

Background:

The aim of this study was to examine the prognostic value of four significant aberrations based on our previous studies by array-CGH to develop a prognostic Fluorescence-in situ-hybridisation (FISH) assay for clear cell renal cell carcinomas (ccRCC).

Methods:

Fluorescence-in situ-hybridisation experiments were performed on 100 ccRCCs (52 metastasised out of 48 non-metastasised). The mean/median follow up of patients was 59/54 months. Commercially available FISH probes were used for each critical chromosomal region (1q21.3, 7q36.3, 9p21.3p24.1 and 20q11.21q13.32). The total number of specific aberrations (TNSA) was calculated for each tumour based on the specific genomic alterations.

Results:

Total number of specific aberrations was the best predictor of metastasis (area under the curve (AUC)=0.814) compared with single aberrations (AUC: 0.619–0.708) and to 11 different combinations of these 4 aberrations in the receiver operating characteristic curve analysis. Total number of specific aberrations, tumour grade and tumour size were independent predictors of metastasis in the multivariate analysis (P<0.001) for the whole cohort as well as for organ-confined tumours. Total number of specific aberrations and grade could also independently predict cancer-specific mortality (CSM). Total number of specific aberrations demonstrated the highest significance in COX proportional hazard models of overall survival (OS), cancer-specific survival (CSS) and progression-free survival (PFS).

Conclusions:

We identified TNSA as an independent prognostic factor which is associated with metastasis occurrence, CSM, OS, CSS and PFS in patients with ccRCCs.

GOLPH3 is a novel marker of poor prognosis and a potential therapeutic target in human renal cell carcinoma

Background:

Golgi phosphoprotein 3 (GOLPH3) has been reported to be involved in the development of several human cancers. The present study was conducted to investigate the expression of GOLPH3 and its prognostic significance in renal cell carcinoma (RCC). Meanwhile, the function of GOLPH3 in human RCC was further investigated in cell culture models.

Methods:

Expression of GOLPH3 was examined in 43 fresh RCC tissues and paired adjacent normal renal tissues by real-time quantitative PCR and western blotting. Immunohistochemistry for GOLPH3 was performed on additional 218 RCC tissues. The clinical significance of GOLPH3 expression was analysed. Downregulation of GOLPH3 was performed using small-interfering RNA (siRNA) in Caki-1 and 786-O cells with high abundance of GOLPH3, and the effects of GOLPH3 silencing on cell proliferation, migration, invasion in vitro, and tumour growth in vivo were evaluated.

Results:

Expression of GOLPH3 was upregulated in the majority of the RCC clinical tissue specimens at both mRNA and protein levels. Clinicopathological analysis showed that GOLPH3 expression was significantly correlated with T stage (P<0.001), lymph-node status (P=0.003), distant metastasis (P<0.001), tumour-node-metastasis (TNM) stage (P<0.001), and Fuhman grade (P=0.001). Expression of GOLPH3 was inversely correlated with both overall and recurrence-free survival of RCC patients. Multivariate analysis showed that GOLPH3 expression was an independent prognostic indicator for patient's survival. Knockdown of the GOLPH3 expression reduced cell proliferation, anchorage-independent growth, migration, invasion, and tumour growth in xenograft model mice.

Conclusions:

These results suggest that GOLPH3 expression is likely to have important roles in RCC development and progression, and that GOLPH3 is a prognostic biomarker and a promising therapeutic target for RCC.

MicroRNA expression signatures of stage, grade, and progression in clear cell RCC

Clear cell RCC is the most common, and more likely to metastasize, of the three main histological types of RCC. Pathologic stage is the most important prognostic indicator and nuclear grade can predict outcome within stages of localized RCC. Epithelial tumors are thought to accumulate a series of genetic and epigenetic changes as they progress through well-defined clinical and histopathological changes. MicroRNAs (miRNAs) are involved in the regulation of mRNA expression from many human genes and miRNA expression is dysregulated in cancer. To better understand the contribution of dysregulated miRNA expression to the progression and biology of ccRCC, we examined the differences in expression levels of 723 human miRNAs through a series of analyses by stage, grade, and disease progression status in a large series of 94 ccRCC. We found a consistent signature that included significant upregulation of miR-21-5p, 142-3p, let-7g-5p, let-7i-5p and 424-5p, as well as downregulation of miR-204-5p, to be associated with ccRCC of high stage, or high grade, or progression. Discrete signatures associated with each of stage, grade, or progression were also identified. The let-7 family was significantly downregulated in ccRCC compared with normal renal parenchyma. Expression of the 6 most significantly differentially expressed miRNAs between ccRCC was verified by stem-loop qRT-PCR. Pathways predicted as targets of the most significantly dysregulated miRNAs included signaling, epithelial cancers, metabolism, and epithelial to mesenchymal transition. Our studies help to further elucidate the biology underlying the progression of ccRCC and identify miRNAs for potential translational application.

Chest X-ray in the follow-up of renal cell carcinoma

PURPOSE

To evaluate the value of chest X-ray in the follow-up of surgically treated T1-3N0M0 renal cell carcinoma.

METHODS

We performed retrospective analysis of patients that underwent surgical treatment of a localized renal cell carcinoma (T1-3N0M0) between January 1993 and July 2010. Data on frequency and results of performed chest X-rays were collected from patients' records.

RESULTS

In 17.5 years, 249 patients with a T1-3N0M0 renal cell carcinoma underwent a radical or partial nephrectomy. In 221 patients, 823 chest X-rays were performed during a median follow-up of 3.3 years (range 0.5-17 years). In 19 patients, a pulmonary recurrence occurred, of which 10 were not detected by the regular follow-up. Of the 9 patients that were diagnosed with a pulmonary recurrence with a chest X-ray during follow-up, 7 were asymptomatic at the time of diagnosis, and the chest X-ray has led to the detection; 0.85 % of the performed chest X-rays (7/823) have led to the detection of asymptomatic lung metastases.

CONCLUSIONS

Due to the low yield of chest X-ray for detection of asymptomatic pulmonary recurrences, it has very low clinical value in the follow-up after nephrectomy for T1-3N0M0 renal cell carcinoma.

Ribosomal s6 protein kinase 4: a prognostic factor for renal cell carcinoma

Background:

The expression and function of ribosomal s6 protein kinase 4 (RSK4) in renal cell carcinoma (RCC) are unknown.

Methods:

Immunohistochemistry was used to detect the expression of RSK4 in RCC, and the relationship between RSK4 expression and clinicopathological features as well as prognosis of RCC patients was statistically analysed. Ectopic RSK4 expression in RCC cell lines was performed to determine its effect on cell cycle regulation, tumour invasiveness, and metastatic capability.

Results:

RSK4 was overexpressed in RCCs (P=0.003), compared with normal tissues, and the expression varied in different RCC subtypes (P=0.021), especially in two subtypes of papillary RCCs (P=0.001). RSK4 expression was positively correlated with high pT stage (P<0.001), high Fuhrman grade (P<0.001), lymph node involvement (P<0.001), and presence of distant metastasis (P=0.039), and could predict poor outcome in RCC patients. Molecular studies showed that overexpression of RSK4 could promote cell cycle progression and enhance the invasive and metastatic capability of RCC cell lines and vice versa.

Conclusion:

The expression pattern and molecular mechanisms of RSK4 in RCCs indicate that it could be a potential independent prognostic factor and serve as a new potential therapeutic target for RCC patients.

Genomics and epigenomics of clear cell renal cell carcinoma: recent developments and potential applications

Majority of clear cell renal cell carcinomas (ccRCCs) are diagnosed in the advanced metastatic stage resulting in dramatic decrease of patient survival. Thereby, early detection and monitoring of the disease may improve prognosis and treatment results. Recent technological advances enable the identification of genetic events associated with ccRCC and reveal significant molecular heterogeneity of ccRCC tumors. This review summarizes recent findings in ccRCC genomics and epigenomics derived from chromosomal aberrations, DNA sequencing and methylation, mRNA, miRNA expression profiling experiments. We provide a molecular insight into ccRCC pathology and recapitulate possible clinical applications of genomic alterations as predictive and prognostic biomarkers.

Validation of the pre-treatment neutrophil-lymphocyte ratio as a prognostic factor in a large European cohort of renal cell carcinoma patients

Background:

The neutrophil–lymphocyte ratio (NLR) has been proposed as an indicator of systemic inflammatory response. Several studies suggest a negative impact of increased NLR for patient's survival in different types of cancer. However, previous findings from small-scale studies revealed conflicting results about its prognostic significance with regard to different clinical end points in non-metastatic renal cell carcinoma (RCC) patients. Therefore, the aim of our study was the validation of the prognostic significance of NLR in a large cohort of RCC patients.

Methods:

Data from 678 consecutive non-metastatic clear cell RCC patients, operated between 2000 and 2010 at a single centre, were evaluated retrospectively. Cancer-specific, metastasis-free, as well as overall survival (OS) were assessed using the Kaplan–Meier method. To evaluate the independent prognostic significance of NLR, multivariate Cox regression models were applied for all three different end points. Influence of the NLR on the predictive accuracy of the Leibovich prognosis score was determined by Harrell's concordance index.

Results:

Multivariate analysis identified increased NLR as an independent prognostic factor for overall (hazard ratio (HR)=1.59, 95% confidence interval (CI)=1.10–2.31, P=0.014), but not for cancer-specific (HR=1.59, 95% CI=0.84–2.99, P=0.148), nor for metastasis-free survival (HR=1.39, 95% CI=0.85–2.28, P=0.184). The estimated concordance index was 0.79 using the Leibovich risk score and 0.81 when NLR was added.

Conclusion:

Regarding patients' OS, an increased NLR represented an independent risk factor, which might reflect a higher risk for severe cardiovascular and other comorbidities. Adding the NLR to well-established prognostic models such as the Leibovich prognosis score might improve their predictive ability.

Hepatitis A virus cellular receptor 1/kidney injury molecule-1 is a susceptibility gene for clear cell renal cell carcinoma and hepatitis A virus cellular receptor/kidney injury molecule-1 ectodomain shedding a predictive biomarker of tumour progression

AIM OF THE STUDY

To correlate hepatitis A virus cellular receptor (HAVCR)/kidney injury molecule-1 (KIM-1) expression in clear cell renal cell carcinoma (ccRCC) tumours with patient outcome and study the consequences of HAVCR/KIM-1 ectodomain shedding.

METHODS

HAVCR/KIM-1 expression in ccRCC, oncocytomes, papillary carcinomas and unaffected tissue counterparts was evaluated. Minimal change disease and pre-clamping normal and ccRCC tissue biopsies were included. Tissue microarrays from 98 ccRCC tumours were analysed. Tumour registry data and patient outcome were retrospectivelly collected. Deletions in HAVCR/KIM-1 ectodomain and lentiviral infection of 786-O cells with HAVCR/KIM-1 mutated constructs to determine their subcellular distribution and invasive capacity were performed.

RESULTS

HAVCR/KIM-1 was expressed in ccRCC, papillary tumours and in tubule cells of adjacent and distal unaffected counterparts of ccRCC tumours. The latest was not related to ischemic or tumour-related paracrine effects since pre-clamping normal biopsies were positive for HAVCR/KIM-1 and unaffected counterparts of papillary tumours were negative. HAVCR/KIM-1 analyses in patients and the invasive capacity of HAVCR/KIM-1 shedding mutants in cell lines demonstrated that: (i) relative low HAVCR/KIM-1 membrane levels correlate with activated shedding in ccRCC patients and mutant cell lines; (ii) augmented shedding directly correlates with higher invasiveness and tumour malignancy. CONCLUDING STATEMENTS: Constitutive expression of HAVCR/KIM-1 in kidney might constitute a susceptibility trait for ccRCC tumour development. Enhanced HAVCR/KIM-1 ectodomain shedding promotes invasive phenotype in vitro and more aggressive tumours in vivo.

NDRG2 is involved in the oncogenic properties of renal cell carcinoma and its loss is a novel independent poor prognostic factor after nephrectomy

BACKGROUND

Although NDRG2 is a candidate tumor suppressor, its exact role in renal cell carcinoma (RCC) is not fully understood. We investigated the functional role of NDRG2 and its clinical relevance in RCC tumorigenesis.

METHODS

NDRG2 expression and its clinical implications in clear cell RCC were evaluated. Biological function was assessed by a proliferation assay, anchorage-independent growth assay, and wound healing and transwell migration assays in RCC cell lines overexpressing NDRG2 coupled with an investigation of the effects of NDRG2 expression on the epithelial-mesenchymal transition (EMT).

RESULTS

NDRG2 was differentially expressed in patients with RCC. A loss of NDRG2 was significantly associated with a higher proportion of tumors >10 cm and a high nuclear grade. Furthermore, multivariate analyses indicated that a loss of NDRG2 was an independent poor prognostic factor for patient survival (recurrence-free survival, hazard ratio 7.901; disease-specific survival, hazard ratio 15.395; overall survival, hazard ratio 11.339; P < 0.001 for all parameters). NDRG2 expression inhibited the anchorage-independent growth and migration of RCC cells. NDRG2 expression also modulated the expression of EMT-related genes such as Snail, Slug, and SIP1, and it decreased EMT signaling in RCC cells. Finally, NDRG2 recovered E-cadherin expression in E-cadherin-negative RCC cells.

CONCLUSIONS

These results indicate that a lack of NDRG2 is associated with oncogenic properties through the loss of its role as a tumor suppressor, and that NDRG2 is an independent poor prognostic factor predicting survival in clear cell RCC, suggesting that it can serve as a novel prognostic biomarker.

CD44 is associated with tumor recurrence and is an independent poor prognostic factor for patients with localized clear cell renal cell carcinoma after nephrectomy

CD44 has been implicated in tumor development and progression in several types of cancer. CD44 expression is altered in renal cell carcinoma (RCC) and has been suggested as a useful prognostic marker, but its prognostic role in RCC remains controversial. We investigated the expression of CD44 in a large homogeneous set of localized clear cell RCC to determine its potential prognostic value. We examined 110 patients with localized clear cell RCC who underwent nephrectomy. The clinicopathological data were obtained retrospectively and the expression level of CD44 was studied by immunohistochemistry. Correlations between CD44 expression and clinical parameters as well as survival were determined. The CD44-high expression group (HEG) was significantly associated with a higher nuclear grade (P=0.014) and tumor recurrence (P<0.001) when compared with the CD44-low expression group (LEG). Concerning survival, the 5-year recurrence-free survival (RFS) rates for the CD44-HEG and CD44-LEG groups were 38.9 and 91.3%, respectively (P<0.001), and the 5-year disease-specific survival (DSS) rates for the CD44-HEG and CD44-LEG groups were 55.6 and 94.6%, respectively (P<0.001). Multivariate analyses showed that CD44 expression [hazard ratio (HR), 9.204; P<0.001] was an independent risk factor predicting RFS in patients with clear cell RCC. CD44 expression remained an independent prognostic factor for DSS (P=0.002). In conclusion, these data indicate that CD44 expression is associated with the progression of clear cell RCC and is an independent poor prognostic factor for tumor recurrence and survival, suggesting that CD44 may serve as a useful molecular marker.

[Role of mitogen-activated protein kinase (MAPK) in the sporadic renal cell carcinoma]

CONTEXT

Only on the basis of the involvement of the vhl suppressor gene in the cases of renal cell carcinomas (RCC), the involvement of the signaling pathway between the pVHL and the Hypoxia inducible factor 1, alpha (HIF-1α) has been evaluated because of the need to find new diagnostic and prognostic and response to drugs markers.

EVIDENCE SYNTHESIS

The overexpression of HIF-1α confers better prognosis in clear cell type RCC (ccRCC). Furthermore, HIF-1α regulates other genes, specifically that of the carbon anhydrase IX (CA-IX), whose overexpression is practically only of the ccRCC and its determination is useful for this subtype. However, the involvement of the CA-IX has not been demonstrated in the prognosis or in the response to immunomodulators or antiangiogenics. Therefore, it is necessary to make a global evaluation of all this pathway: pVHL → HIF-1α → CA-IX, and even the analysis of other proteins and signaling pathways that also control the HIF-1α activity. In the latter case, the MAPK are critical in the HIF-1α activation, there being evidence on the experimental level of the control on its activity. although its clinical role as a biomarkers has not been established. Although the role of the MAPK in the phenomena of resistance to conventional chemotherapy and radiotherapy has been demonstrated, it has not been demonstrated in response to sorafenib, an important piece of information if we consider that it is an inhibitor of several protein kinases. Recently, it has been observed that the MAPK may be involved in the responses to different therapies, included those based on tyrosine kinase inhibitors.

CONCLUSIONS

The confirmation of these data would suppose an explanation of the variation observed between patients who, with the same functional alteration of the vhl gene, have a different biological, clinical behavior and better selection of non-surgical therapies.

Prognostic variables and nomograms for renal cell carcinoma

The term renal cell carcinoma (RCC) is used to describe a heterogeneous group of tumors that vary histologically, genetically and molecularly. Extensive research has been conducted to identify characteristics that predict outcomes among patients with RCC. In addition to histological subtype these include tumor size, patient age, mode of presentation and various hematological indices, among others. Several groups have incorporated these clinical and pathological features into nomograms which help the clinician better define individual patient prognosis and direct the optimum therapeutic approach. In the present article we review these prognostic variables and nomograms for RCC.

Analysis of energy utilization and body composition in kidney, bladder, and adrenal cancer patients

OBJECTIVE

To investigate resting energy expenditure (REE) and body composition and the relationship between substrate utilization and energy expenditure in urologic cancer patients.

PATIENTS AND METHODS

Measured resting energy expenditure (mREE) was detected by indirect calorimetry in 122 urologic cancer patients and 131 control subjects. Extracellular fluid (ECF), intracellular fluid (ICF), and total water (TW) were measured by bioelectrical impedance appliance. Fat oxidation rate (F-O), carbohydrate oxidation rate, fat mass (FM), and fat free mass (FFM) were further determined.

RESULTS

Compared with the controls, cancer patients showed significantly elevated mREE and mREE/FFM (P = 0.049; P < 0.001). Of all the cancer patients, 50% (n = 61) were hypermetabolic, 43.4% (n = 53) normometabolic, and 6.6% (n = 8) hypometabolic, whereas 35.1% (n = 46) of the controls were hypermetabolic, 56.5% (n = 74) normometabolic, and 8.4% (n = 11) hypometabolic. REE was correlated to substrate oxidation rate (R(2) = 0.710). Cancer patients exhibited no significant difference in FM, FM/body weight (BW) and FFM, compared with controls. Cancer patients presented no significant difference in TW compared with controls (P = 0.791), but they had increased ECF (P < 0.001) and decreased ICF (P < 0.001).

CONCLUSION

Aberrations in substrate utilization may contribute to the elevated energy expenditure in urologic cancer patients. Cancer type and pathologic stage are influential factors of REE.

Genetic variations in microRNA-related genes are associated with survival and recurrence in patients with renal cell carcinoma

We took a polygenic approach to evaluate the effects of 41 potentially functional single-nucleotide polymorphisms (SNPs) in microRNAs (miRNAs)-related genes on survival and recurrence among renal cell carcinoma (RCC) patients. During a median follow-up of 21.8 months, among 316 RCC patients, 64 died and 56 developed recurrence. In single-SNP analysis, we identified seven SNPs significantly associated with RCC survival and five SNPs with recurrence. The most significant associations were SNPs in GEMIN4 with the variant alleles of both rs7813 and rs910925 associated with 1.74-fold [95% confidence interval (CI) = 1.15-2.62] increased risk of death, whereas the variant allele of rs3744741 conferred a decreased risk of death [hazard ratio (HR) = 0.39; 95% CI = 0.19-0.77]. Several SNPs belonging to the pre-miRNA and were identified to be significantly associated with RCC recurrence. Haplotypes of DICER and DROSHA were also associated with altered patient survival and recurrence. More importantly, we observed cumulative effects of multiple SNPs on RCC survival. Compared with subjects carrying zero to two unfavorable genotypes, those carrying three to five and six and more unfavorable genotypes had an increased risk of death with a HR of 2.49 (95% CI = 1.24-5.00) and 6.66 (95% CI = 2.49-17.86), respectively, with significant dose-response trend (P for trend<0.001). As the first study of miRNA-related genetic polymorphisms on RCC clinical outcome, our results strongly suggested that miRNA-related SNPs may impact the recurrence and survival in RCC patients. Future investigation in larger populations and functional characterizations are necessary to validate these results.

Dysregulation of kallikrein-related peptidases in renal cell carcinoma: potential targets of miRNAs

Renal cell carcinoma (RCC) accounts for 3% of all adult malignancies and currently no diagnostic marker exists. Kallikrein-related peptidases (KLKs) have been implicated in numerous cancers including ovarian, prostate, and breast carcinoma. KLKs 5, 6, 10, and 11 have decreased expression in RCC when compared to normal kidney tissue. Our bioinformatic analysis indicated that theKLK 1,6, and7genes have decreased expression in RCC. We experimentally verified these results and found that decreased expression ofKLKs 1and3were significantly associated with the clear cell RCC subtype (p<0.001). An analysis of miRNAs differentially expressed in RCC showed that 61 of the 117 miRNAs that were reported to be dysregulated in RCC were predicted to target KLKs. We experimentally validated two targets using two independent approaches. Transfection of miR-224 into HEK-293 cells resulted in decreased KLK1 protein levels. A luciferase assay demonstrated that hsa-let-7f can target KLK10 in the RCC cell line ACHN. Our results, showing differential expression of KLKs in RCC, suggest that KLKs could be novel diagnostic markers for RCC and that their dysregulation could be under miRNA control. The observation that KLKs could represent targets for miRNAs suggests a post-transcriptional regulatory mechanism with possible future therapeutic applications.

Renal cell carcinoma

Renal Cell Carcinoma (RCC) has the highest mortality rate of the genitourinary cancers and the incidence of RCC has risen steadily. If detected early, RCC is curable by surgery although a minority are at risk of recurrence. Increasing incidental detection and an ageing population has led to active surveillance as an option for patients with small renal masses. RCC is heterogeneous and comprises several histological cell types with different genetics, biology and behavior. The identification of the genes predisposing to inherited syndromes with RCC has provided much of our knowledge of the molecular basis of early sporadic RCC. Many of the oncogenes and tumor suppressor genes that are mutated leading to pathway dysregulation in RCC remain to be elucidated. Global studies of copy number, gene sequencing, gene expression, miRNA expression and gene methylation in primary RCC will lead towards this goal. The natural history of RCC indicated by candidate precursor lesions, multifocal or bilateral disease, growth rate of small renal masses under surveillance, and high risk populations provide insight into the behavior of this disease. The use of molecular markers for early detection and prognosis merits more attention with ongoing advances in omics technologies. This review focuses on early RCC, that is disease confined within the renal capsule.