The incidence of renal cell carcinoma (RCC) is increasing worldwide, and its prevalence is particularly high in some parts of Central Europe. Here we undertake whole-genome and transcriptome ...sequencing of clear cell RCC (ccRCC), the most common form of the disease, in patients from four different European countries with contrasting disease incidence to explore the underlying genomic architecture of RCC. Our findings support previous reports on frequent aberrations in the epigenetic machinery and PI3K/mTOR signalling, and uncover novel pathways and genes affected by recurrent mutations and abnormal transcriptome patterns including focal adhesion, components of extracellular matrix (ECM) and genes encoding FAT cadherins. Furthermore, a large majority of patients from Romania have an unexpected high frequency of A:T>T:A transversions, consistent with exposure to aristolochic acid (AA). These results show that the processes underlying ccRCC tumorigenesis may vary in different populations and suggest that AA may be an important ccRCC carcinogen in Romania, a finding with major public health implications.
Abstract Context Marked unexplained national variations in incidence rates of kidney cancer have been observed for decades in Europe. Objective To investigate geographic variations at the regional ...level and identify European regions with high incidence rates of kidney cancer. Evidence acquisition Regional- and national-level incidence data were extracted from the Cancer Incidence in Five Continents databases, local cancer registry databases, and local published reports. World population age-standardised rates (ASRs) were calculated for the periods 2003–2007 and 1988–1992. Rates by period and sex were compared using map visualisation. Evidence synthesis During 2003–2007, the highest ASR was found in the Plzen region, Czech Republic (31.4/100 000 person-years in men). Other regions of the Czech Republic had ASRs of 18.6–27.5/100 000 in men, with a tendency for higher rates in regions south of Prague. Surrounding regions, including eastern Germany and regions of Slovakia and Austria, had medium-to-high incidence rates (13.0–16.8/100 000 in men). Three other areas in Europe showed higher incidence rates in men compared with the rest of the continent: Lithuania, Estonia, Latvia, and Belarus (15.0–17.6/100 000); Iceland (13.5/100 000), and northern Italy (up to 16.0/100 000). Similar regional differences were observed among women, with rates approximately half of those observed in men in the same region. In general, these regional geographic variations remained stable over the periods 1988–1992 and 2003–2007, although higher incidence rates were detected in the Baltic countries in 2003–2007. Conclusions Several European regions show particularly high rates of kidney cancer incidence. Large variations were observed within countries covered by national health-care systems, implying that overdetection is not the major factor. Patient summary We present regional geographic variations in kidney cancer incidence rates in Europe. We highlight several regions with high incidence rates where further studies should be conducted for cancer control and prevention.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Background: Domestic fuel combustion from cooking and heating is an important public health issue because roughly 3 billion people are exposed worldwide. Recently, the International Agency for ...Research on Cancer classified indoor emissions from household coal combustion as a human carcinogen (group 1) and from biomass fuel (primarily wood) as a probable human carcinogen (group 2A). Objectives: We pooled seven studies from the International Lung Cancer Consortium (5,105 cases and 6,535 controls) to provide further epidemiological evaluation of the association between in-home solid-fuel use, particularly wood, and lung cancer risk. Methods: Using questionnaire data, we classified subjects as predominant solid-fuel users (e. g., coal, wood) or nonsolid-fuel users (e.g., oil, gas, electricity). Unconditional logistic regression was used to estimate the odds ratios (ORs) and to compute 95% confidence intervals (CIs), adjusting for age, sex, education, smoking status, race/ethnicity, and study center. Results: Compared with nonsolid-fuel users, predominant coal users (OR = 1.64; 95% CI, 1.49-1.81), particularly coal users in Asia (OR = 4.93; 95% CI, 3.73-6.52), and predominant wood users in North American and European countries (OR = 1.21; 95% CI, 1.06-1.38) experienced higher risk of lung cancer. The results were similar in never-smoking women and other subgroups. Conclusions: Our results are consistent with previous observations pertaining to in-home coal use and lung cancer risk, support the hypothesis of a carcinogenic potential of in-home wood use, and point to the need for more detailed study of factors affecting these associations.
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BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
Assessing the relationship between lung cancer and metabolic conditions is challenging because of the confounding effect of tobacco. Mendelian randomization (MR), or the use of genetic instrumental ...variables to assess causality, may help to identify the metabolic drivers of lung cancer.
We identified genetic instruments for potential metabolic risk factors and evaluated these in relation to risk using 29,266 lung cancer cases (including 11,273 adenocarcinomas, 7,426 squamous cell and 2,664 small cell cases) and 56,450 controls. The MR risk analysis suggested a causal effect of body mass index (BMI) on lung cancer risk for two of the three major histological subtypes, with evidence of a risk increase for squamous cell carcinoma (odds ratio (OR) 95% confidence interval (CI) = 1.20 1.01-1.43 and for small cell lung cancer (OR 95%CI = 1.52 1.15-2.00) for each standard deviation (SD) increase in BMI 4.6 kg/m2), but not for adenocarcinoma (OR 95%CI = 0.93 0.79-1.08) (Pheterogeneity = 4.3x10-3). Additional analysis using a genetic instrument for BMI showed that each SD increase in BMI increased cigarette consumption by 1.27 cigarettes per day (P = 2.1x10-3), providing novel evidence that a genetic susceptibility to obesity influences smoking patterns. There was also evidence that low-density lipoprotein cholesterol was inversely associated with lung cancer overall risk (OR 95%CI = 0.90 0.84-0.97 per SD of 38 mg/dl), while fasting insulin was positively associated (OR 95%CI = 1.63 1.25-2.13 per SD of 44.4 pmol/l). Sensitivity analyses including a weighted-median approach and MR-Egger test did not detect other pleiotropic effects biasing the main results.
Our results are consistent with a causal role of fasting insulin and low-density lipoprotein cholesterol in lung cancer etiology, as well as for BMI in squamous cell and small cell carcinoma. The latter relation may be mediated by a previously unrecognized effect of obesity on smoking behavior.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Recent genome-wide association studies (GWASs) have identified common genetic variants at 5p15.33, 6p21-6p22 and 15q25.1 associated with lung cancer risk. Several other genetic regions including ...variants of CHEK2 (22q12), TP53BP1 (15q15) and RAD52 (12p13) have been demonstrated to influence lung cancer risk in candidate- or pathway-based analyses. To identify novel risk variants for lung cancer, we performed a meta-analysis of 16 GWASs, totaling 14 900 cases and 29 485 controls of European descent. Our data provided increased support for previously identified risk loci at 5p15 (P = 7.2 × 10(-16)), 6p21 (P = 2.3 × 10(-14)) and 15q25 (P = 2.2 × 10(-63)). Furthermore, we demonstrated histology-specific effects for 5p15, 6p21 and 12p13 loci but not for the 15q25 region. Subgroup analysis also identified a novel disease locus for squamous cell carcinoma at 9p21 (CDKN2A/p16(INK4A)/p14(ARF)/CDKN2B/p15(INK4B)/ANRIL; rs1333040, P = 3.0 × 10(-7)) which was replicated in a series of 5415 Han Chinese (P = 0.03; combined analysis, P = 2.3 × 10(-8)). This large analysis provides additional evidence for the role of inherited genetic susceptibility to lung cancer and insight into biological differences in the development of the different histological types of lung cancer.
Purpose: To provide a comprehensive, thorough analysis of somatic mutation and promoter hypermethylation of the von Hippel-Lindau ( VHL ) gene in the cancer genome, unique to clear cell renal cancer ...(ccRCC). Identify relationships between the prevalence of VHL gene alterations and alteration subtypes with patient and tumor characteristics.
Experimental Design: As part of a large kidney cancer case-control study conducted in Central Europe, we analyzed VHL mutations and promoter methylation in 205 well-characterized, histologically confirmed patient tumor biopsies using a combination
of sensitive, high-throughput methods (endonuclease scanning and Sanger sequencing) and analysis of 11 CpG sites in the VHL promoter.
Results: We identified mutations in 82.4% of cases, the highest VHL gene mutation prevalence reported to date. Analysis of 11 VHL promoter CpG sites revealed that 8.3% of tumors were hypermethylated and all were mutation negative. In total, 91% of ccRCCs
exhibited alteration of the gene through genetic or epigenetic mechanisms. Analysis of patient and tumor characteristics revealed
that certain mutation subtypes were significantly associated with Fuhrman nuclear grade, metastasis, node positivity, and
self-reported family history of RCC.
Conclusion: Detection of VHL gene alterations using these accurate, sensitive, and practical methods provides evidence that the vast majority of histologically
confirmed ccRCC tumors possess genetic or epigenetic alteration of the VHL gene and support the hypothesis that VHL alteration is an early event in ccRCC carcinogenesis. These findings also indicate that VHL molecular subtypes can provide a sensitive marker of tumor heterogeneity among histologically similar ccRCC cases for etiologic,
prognostic, and translational studies.
Renal tumor heterogeneity studies have utilized the von Hippel-Lindau VHL gene to classify disease into molecularly defined subtypes to examine associations with etiologic risk factors and prognosis. ...The aim of this study was to provide a comprehensive analysis of VHL inactivation in clear cell renal tumors (ccRCC) and to evaluate relationships between VHL inactivation subgroups with renal cancer risk factors and VHL germline single nucleotide polymorphisms (SNPs). VHL genetic and epigenetic inactivation was examined among 507 sporadic RCC/470 ccRCC cases using endonuclease scanning and using bisulfite treatment and Sanger sequencing across 11 CpG sites within the VHL promoter. Case-only multivariate analyses were conducted to identify associations between alteration subtypes and risk factors. VHL inactivation, either through sequence alterations or promoter methylation in tumor DNA, was observed among 86.6% of ccRCC cases. Germline VHL SNPs and a haplotype were associated with promoter hypermethylation in tumor tissue (OR = 6.10; 95% CI: 2.28-16.35, p = 3.76E-4, p-global = 8E-5). Risk of having genetic VHL inactivation was inversely associated with smoking due to a higher proportion of wild-type ccRCC tumors former: OR = 0.70 (0.20-1.31) and current: OR = 0.56 (0.32-0.99); P-trend = 0.04. Alteration prevalence did not differ by histopathologic characteristics or occupational exposure to trichloroethylene. ccRCC cases with particular VHL germline polymorphisms were more likely to have VHL inactivation through promoter hypermethylation than through sequence alterations in tumor DNA, suggesting that the presence of these SNPs may represent an example of facilitated epigenetic variation (an inherited propensity towards epigenetic variation) in renal tissue. A proportion of tumors from current smokers lacked VHL alterations and may represent a biologically distinct clinical entity from inactivated cases.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Recent studies support an important role for human papillomavirus (HPV) in a subgroup of head and neck squamous cell carcinomas (HNSCC). We have evaluated the HPV deoxyribonucleic acid (DNA) ...prevalence as well as the association between serological response to HPV infection and HNSCC in two distinct populations from Central Europe (CE) and Latin America (LA).
Cases (n = 2214) and controls (n = 3319) were recruited from 1998 to 2003, using a similar protocol including questionnaire and blood sample collection. Tumour DNA from 196 fresh tissue biopsies was analysed for multiple HPV types followed by an HPV type-specific polymerase chain reaction (PCR) protocol towards the E7 gene from HPV 16. Using multiplex serology, serum samples were analysed for antibodies to 17 HPV types. Statistical analysis included the estimation of adjusted odds ratios (ORs) and the respective 95% confidence intervals (CIs).
HPV16 E7 DNA prevalence among cases was 3.1% (6/196), including 4.4% in the oropharynx (3/68), 3.8% in the hypopharynx/larynx (3/78) and 0% among 50 cases of oral cavity carcinomas. Positivity for both HPV16 E6 and E7 antibodies was associated with a very high risk of oropharyngeal cancer (OR = 179, 95% CI 35.8-899) and hypopharyngeal/laryngeal cancer (OR = 14.9, 95% CI 2.92-76.1).
A very low prevalence of HPV DNA and serum antibodies was observed among cases in both CE and LA. The proportion of head and neck cancer caused by HPV may vary substantially between different geographical regions and studies that are designed to evaluate the impact of HPV vaccination on HNSCC need to consider this heterogeneity.
Cigarette smoking is a major risk factor for head and neck cancer (HNC). To our knowledge, low cigarette smoking (<10 cigarettes per day) has not been extensively investigated in fine categories or ...among never alcohol drinkers.
We conducted a pooled analysis of individual participant data from 23 independent case-control studies including 19 660 HNC cases and 25 566 controls. After exclusion of subjects using other tobacco products including cigars, pipes, snuffed or chewed tobacco and straw cigarettes (tobacco product used in Brazil), as well as subjects smoking more than 10 cigarettes per day, 4093 HNC cases and 13 416 controls were included in the analysis. The lifetime average frequency of cigarette consumption was categorized as follows: never cigarette users, >0-3, >3-5, >5-10 cigarettes per day.
Smoking >0-3 cigarettes per day was associated with a 50% increased risk of HNC in the study population odds ratio (OR) = 1.52, 95% confidence interval (CI): (1.21, 1.90). Smoking >3-5 cigarettes per day was associated in each subgroup from OR = 2.01 (95% CI: 1.22, 3.31) among never alcohol drinkers to OR = 2.74 (95% CI: 2.01, 3.74) among women and in each cancer site, particularly laryngeal cancer (OR = 3.48, 95% CI: 2.40, 5.05). However, the observed increased risk of HNC for low smoking frequency was not found among smokers with smoking duration shorter than 20 years.
Our results suggest a public health message that low frequency of cigarette consumption contributes to the development of HNC. However, smoking duration seems to play at least an equal or a stronger role in the development of HNC.
Several epidemiological studies have shown a positive association between adult height and cancer incidence. The only study conducted among women on mouth and pharynx cancer risk, however, reported ...an inverse association. This study aims to investigate the association between height and the risk of head and neck cancer (HNC) within a large international consortium of HNC. We analyzed pooled individual-level data from 24 case-control studies participating in the International Head and Neck Cancer Epidemiology Consortium. Odds ratios (ORs) and 95 % confidence intervals (CIs) were estimated separately for men and women for associations between height and HNC risk. Educational level, tobacco smoking, and alcohol consumption were included in all regression models. Stratified analyses by HNC subsites were performed. This project included 17,666 cases and 28,198 controls. We found an inverse association between height and HNC (adjusted OR per 10 cm height = 0.91, 95 % CI 0.86-0.95 for men; adjusted OR = 0.86, 95 % CI 0.79-0.93 for women). In men, the estimated OR did vary by educational level, smoking status, geographic area, and control source. No differences by subsites were detected. Adult height is inversely associated with HNC risk. As height can be considered a marker of childhood illness and low energy intake, the inverse association is consistent with prior studies showing that HNC occur more frequently among deprived individuals. Further studies designed to elucidate the mechanism of such association would be warranted.