Previous genome-wide association studies (GWAS) have identified six risk loci for renal cell carcinoma (RCC). We conducted a meta-analysis of two new scans of 5,198 cases and 7,331 controls together with four existing scans, totalling 10,784 cases and 20,406 controls of European ancestry. Twenty-four loci were tested in an additional 3,182 cases and 6,301 controls. We confirm the six known RCC risk loci and identify seven new loci at 1p32.3 (rs4381241, P=3.1 × 10−10), 3p22.1 (rs67311347, P=2.5 × 10−8), 3q26.2 (rs10936602, P=8.8 × 10−9), 8p21.3 (rs2241261, P=5.8 × 10−9), 10q24.33-q25.1 (rs11813268, P=3.9 × 10−8), 11q22.3 (rs74911261, P=2.1 × 10−10) and 14q24.2 (rs4903064, P=2.2 × 10−24). Expression quantitative trait analyses suggest plausible candidate genes at these regions that may contribute to RCC susceptibility.

BackgroundSeveral obesity-related factors have been associated with renal cell carcinoma (RCC), but it is unclear which individual factors directly influence risk. We addressed this question using genetic markers as proxies for putative risk factors and evaluated their relation to RCC risk in a mendelian randomization (MR) framework. This methodology limits bias due to confounding and is not affected by reverse causation.Methods and findingsGenetic markers associated with obesity measures, blood pressure, lipids, type 2 diabetes, insulin, and glucose were initially identified as instrumental variables, and their association with RCC risk was subsequently evaluated in a genome-wide association study (GWAS) of 10,784 RCC patients and 20,406 control participants in a 2-sample MR framework. The effect on RCC risk was estimated by calculating odds ratios (ORSD) for a standard deviation (SD) increment in each risk factor. The MR analysis indicated that higher body mass index increases the risk of RCC (ORSD: 1.56, 95% confidence interval [CI] 1.44–1.70), with comparable results for waist-to-hip ratio (ORSD: 1.63, 95% CI 1.40–1.90) and body fat percentage (ORSD: 1.66, 95% CI 1.44–1.90). This analysis further indicated that higher fasting insulin (ORSD: 1.82, 95% CI 1.30–2.55) and diastolic blood pressure (DBP; ORSD: 1.28, 95% CI 1.11–1.47), but not systolic blood pressure (ORSD: 0.98, 95% CI 0.84–1.14), increase the risk for RCC. No association with RCC risk was seen for lipids, overall type 2 diabetes, or fasting glucose.ConclusionsThis study provides novel evidence for an etiological role of insulin in RCC, as well as confirmatory evidence that obesity and DBP influence RCC risk.

DJ-1 is as a novel regulator of the tumor suppressor PTEN with stimulatory effects on PI3K-AKT/PKB signaling, one possible target of which is cMyc. The catalytic unit of the telomerase complex, hTERT, can be activated at different levels, including transcriptionally by cMyc and through phosphorylation by AKT/PKB. The aim of the study was to analyze the putative signaling pathway encompassing DJ-1, cMyc and hTERT in a series of 176 renal cell carcinomas (RCC) and experimentally in cell lines. DJ-1 mRNA expression was significantly elevated in clear cell RCC (ccRCC) compared with in papillary RCC (pRCC; p 5 0.005) and kidney cortex tissue (p < 0.001). ccRCC and pRCC demonstrated higher cMyc RNA levels than in kidney cortex (p < 0.001 for both) as well as increased levels of hTERT RNA (p < 0.001 and p 5 0.011, respectively). DJ-1 was positively correlated to cMyc and hTERT in ccRCC (p < 0.001 and p 5 0.019, respectively), but not in pRCC, indicating that this pathway could have a functional significance in ccRCC. siRNA knock down of DJ-1 induced downregulation of cMyc and hTERT mRNA associated with decreased expression of pAKT and cMyc protein levels. hTERT promoter activity was upregulated after DJ-1 transfection and this upregulation was inhibited after mutation of the cMyc binding sites. These experimental data support the functional link among DJ-1, cMyc and hTERT expression as indicated in the tumor material. Neither DJ-1, cMyc nor hTERT mRNA levels were associated with proliferation (S-phase fraction), telomere length or prognosis in ccRCC. ' UICCKey words: renal cell carcinoma; DJ-1; cMyc; hTERT; telomere length; proliferation; prognosis Renal cell carcinoma (RCC) constitutes a heterogeneous group of tumors regarding cytogenetic aberrations, morphologic appearance and clinical outcome. The WHO classification identifies different morphologic subtypes of sporadic RCC including the three most common types, clear cell (ccRCC), papillary (pRCC) and chromophobe RCC. 1 Each entity shows characteristic cytogenetic abnormalities indicating essential differences between the RCC subtypes regarding the mechanisms leading to tumor development.The phosphatase tensin homologue deleted on chromosome 10 (PTEN) protein is a well known tumor suppressor acting as a negative regulator of the phosphoinositide-3 (PI-3)-kinase pathway including the downstream Protein Kinase B (PKB)/Akt protein. In RCC, an association between decreased PTEN expression and high PKB/Akt activation has been described. 2 A novel protein, DJ-1 (also called Cap1/RS/PARK7), has been proposed to be involved in tumorigenesis by negatively regulating PTEN. 3 DJ-1 was first described as a protein showing a cooperative transforming activity with H-Ras in mouse NIH3T3 cells. 4 Overexpression of DJ-1 has been reported in several malignancies, including breast and lung. 5,6 Further, DJ-1 mRNA expression levels seemed to be associated with survival in lung cancer 3 and elevated levels of circulating DJ-1 and anti-DJ-1 auto-antibodies were detected in breast cance...

We screened promoter region of the telomerase reverse transcriptase (TERT) for activating somatic mutations in 188 tumors from patients with clear cell renal cell carcinoma (ccRCC). Twelve tumors (6.4%) carried a mutation within the core promoter region of the gene. The mutations were less frequent in high grade tumors compared to low grade tumors [odds ratio (OR) 5 0.15, 95% confidence interval (CI) 5 0.03-0.72, p 5 0.02]. Multivariate analysis for cause specific survival showed statistically significant poor outcome in patients with TERT promoter mutations [hazard ratio (HR) 5 2.90, 95% CI 5 1.13-7.39, p 5 0.03]. A common polymorphism (rs2853669) within the locus seemed to act as a modifier of the effect of the mutations on patient survival as the noncarriers of the variant allele with the TERT promoter mutations showed worst survival (HR 5 3.34, 95% CI 5 1.24-8.98, p 5 0.02). We also measured relative telomere length (RTL) in tumors and difference between tumors with and without the TERT promoter mutations was not statistically significant. Similarly, no difference in patient survival based on RTL in tumors was observed. Our study showed a relatively low frequency of TERT promoter mutations in ccRCC. Nevertheless, patients with the mutations, particularly in the absence of the rs2853669 variant showed the worst disease-specific survival. Thus, it is possible that the TERT promoter mutations define a small subset of tumors with an aggressive behavior.The human telomerase reverse transcriptase (TERT) gene encodes the catalytic subunit of telomerase, a ribonucleoprotein complex that maintains genomic integrity through de novo synthesis of telomere repeat units at chromosomal ends.1 Activation of telomerase is dependent on a number of factors in which the transcriptional regulation of the TERT gene constitutes a rate limiting step. The TERT promoter harbors binding sites for a number of transcriptional activators and repressors and is considered to be the most important regulatory element for telomerase expression.2 Since initial discovery, activating somatic mutations in the promoter region in the TERT gene have been reported in many cancers.3, 4 The promoter mutations result in creation of binding sites for the E-twenty Six (ETS)/ternary complex factors (TCFs) transcription factors located mainly at two residues at 2124C > T (G > A) and 2146C > T (G > A) from the ATG start site in the TERT promoter. The mutations in the TERT promoter result in increased TERT expression and have been shown to be associated with more advanced forms of malignant diseases. In primary cutaneous melanoma the mutations were associated with increased patient age, increased tumor thickness and tumor ulceration. 5In bladder cancer and gliomas, the mutations were associated with risk of tumor recurrence and poor survival. 6,7 In thyroid cancer, the TERT promoter mutations were more frequent in advanced tumors. 4 In follicular thyroid cell-derived carcinomas, the TERT promoter mutations have been shown to be associated with increased age a...

Background:Wilms' tumour 1 (WT1) gene was discovered as a tumour suppressor gene. Later findings have suggested that WT1 also can be oncogenic. This complexity is partly explained by the fact that WT1 has a number of target genes.Method:WT1 and its target gene human telomerase reverse transcriptase (hTERT) were analysed in clear cell renal cell carcinoma (ccRCC). In vitro experiments were performed to examine the functional link between WT1 and hTERT by overexpression of WT1 isoforms in the ccRCC cell line, TK-10.Results:WT1 demonstrated lower RNA expression in ccRCC compared with renal cortical tissue, whereas hTERT was increased, showing a negative correlation between WT1 and hTERT (P=0.005). These findings were experimentally confirmed in vitro. The WT1 generated effect on hTERT promoter activity seemed complex, as several negative regulators of hTERT transcription, such as SMAD3, JUN (AP-1) and ETS1, were activated by WT1 overexpression. Downregulation of potential positive hTERT regulators, such as cMyc, AP-2α, AP-2γ, IRF1, NFX1 and GM-CSF, were also observed. Chromatin immunoprecipitation analysis verified WT1 binding to the hTERT, cMyc and SMAD3 promoters.Conclusion:The collected data strongly indicate multiple pathways for hTERT regulation by WT1 in ccRCC.

The molecular mechanisms whereby transforming growth factor-β (TGF-β) promotes clear cell renal cell carcinoma (ccRCC) progression is elusive. The cell membrane bound TGF-β type I receptor (ALK5), was recently found to undergo proteolytic cleavage in aggressive prostate cancer cells, resulting in liberation and subsequent nuclear translocation of its intracellular domain (ICD), suggesting that ALK5-ICD might be a useful cancer biomarker. Herein, the possible correlation between ALK5 full length (ALK5-FL) and ALK5-ICD protein, phosphorylated Smad2/3 (pSmad2/3), and expression of TGF-β target gene PAI-1, was investigated in a clinical ccRCC material, in relation to tumor grade, stage, size and cancer specific survival. Expression of ALK5-FL, ALK5-ICD, pSmad2/3 and PAI-1 protein levels were significantly higher in higher stage and associated with adverse survival. ALK5-ICD, pSmad2/3 and PAI-1 correlated with higher grade, and ALK5-FL, pSmad2/3 and PAI-1 protein levels were significantly correlated with larger tumor size. Moreover, the functional role of the TGF-β - ALK5-ICD pathway were investigated in two ccRCC cell lines by treatment with ADAM/MMP2 inhibitor TAPI-2, which prevented TGF-β-induced ALK5-ICD generation, nuclear translocation, as well as cell invasion. The present study demonstrated that canonical TGF-β Smad2/3 pathway and generation of ALK5-ICD correlates with poor survival and invasion of ccRCC in vitro.

A SOMA for the CCRCC-specific SPC prognostic gene signature that is predictive of disease-specific survival and independent of stage was constructed and validated, confirming that SOMA construction is feasible.

Background Relative telomere length in peripheral blood leukocytes has been evaluated as a potential biomarker for renal cell carcinoma (RCC) risk in several studies, with conflicting findings. Objective We performed an analysis of genetic variants associated with leukocyte telomere length to assess the relationship between telomere length and RCC risk using Mendelian randomization, an approach unaffected by biases from temporal variability and reverse causation that might have affected earlier investigations. Design, setting, and participants Genotypes from nine telomere length-associated variants for 10 784 cases and 20 406 cancer-free controls from six genome-wide association studies (GWAS) of RCC were aggregated into a weighted genetic risk score (GRS) predictive of leukocyte telomere length. Outcome measurements and statistical analysis Odds ratios (ORs) relating the GRS and RCC risk were computed in individual GWAS datasets and combined by meta-analysis. Results and limitations Longer genetically inferred telomere length was associated with an increased risk of RCC (OR = 2.07 per predicted kilobase increase, 95% confidence interval [CI]: = 1.70–2.53, p < 0.0001). As a sensitivity analysis, we excluded two telomere length variants in linkage disequilibrium (R2 > 0.5) with GWAS-identified RCC risk variants (rs10936599 and rs9420907) from the telomere length GRS; despite this exclusion, a statistically significant association between the GRS and RCC risk persisted (OR = 1.73, 95% CI = 1.36–2.21, p < 0.0001). Exploratory analyses for individual histologic subtypes suggested comparable associations with the telomere length GRS for clear cell (N = 5573, OR = 1.93, 95% CI = 1.50–2.49, p < 0.0001), papillary (N = 573, OR = 1.96, 95% CI = 1.01–3.81, p = 0.046), and chromophobe RCC (N = 203, OR = 2.37, 95% CI = 0.78–7.17, p = 0.13). Conclusions Our investigation adds to the growing body of evidence indicating some aspect of longer telomere length is important for RCC risk. Patient summary Telomeres are segments of DNA at chromosome ends that maintain chromosomal stability. Our study investigated the relationship between genetic variants associated with telomere length and renal cell carcinoma risk. We found evidence suggesting individuals with inherited predisposition to longer telomere length are at increased risk of developing renal cell carcinoma.