Cancer Genetic Markers of Susceptibility for Bladder Cancer (CGEMS Bladder)

This study funded by the National Cancer Institute (NCI) involves conducting a genome-wide association study of common genetic variants to identify markers of susceptibility to bladder cancer. This bladder GWAS has led to the discovery of three novel regions in the genome associated with bladder cancer risk. Cases were defined as individuals having histologically confirmed primary carcinoma of the urinary bladder, including carcinoma in situ (ICD-0-2 topography codes C67.0-C67.9 or ICD9 codes 188.1-188.9). Scan data were obtained from two case-control studies carried out in Spain and the United States (specifically, those in the Maine and Vermont components of the New England Bladder Cancer Study) and three prospective cohort studies in Finland and the United States (specifically Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study, Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial, and The American Cancer Society Cancer Prevention Study II Nutrition Cohort). We used data from 591,637 single nucleotide polymorphisms 3,532 affected individuals (cases) and 5,119 controls of European descent and replication including 8382 cases and 48275 controls from 16 studies. In a combined analysis, we identified three new regions associated with bladder cancer on chromosomes 22q13.1, 19q12 and 2q37.1: rs1014971, (P ≈ 8 x 10-12) maps to a non-genic region of chromosome 22q13.1, rs8102137 (P = 2 x 10-11) on maps to CCNE1 and rs11892031 (P = 1 x 10-7) maps to the UGT1A cluster on 2q37.1. We confirmed four previously identified genome-wide associations on chromosomes 3q28, 4p16.3, 8q24.21 and 8q24.3 (Rothman N et al., Nature Genetics, 2010, PMID: 20972438). Through meta-analysis with the MD Anderson Texas Bladder Cancer Study (TXBCS), we also identified a novel susceptibility locus that mapped to a region of 18q12.3, marked by rs7238033 (P = 8.7 x 10(-9); allelic odds ratio 1.20 with 95% CI: 1.13-1.28) and two highly correlated SNPs, rs10775480/rs10853535 (r(2)= 1.00; P = 8.9 x 10(-9); allelic odds ratio 1.16 with 95% CI: 1.10-1.22) (Garcia-Closas M et al, Human Molecular Genetics, 2011) For NCI-GWAS2, we performed genotyping on cases and controls for the New Hampshire component of the New England Bladder Cancer Study (NEBCS-NH). For the majority of new bladder cancer cases, we genotyped only cases from four case-control studies, the Los Angeles Bladder Cancer Study (LABCS), the French Center for Research on Prostate Diseases (CeRePP), the French Bladder Study (FBCS) and the Brescia Bladder Cancer Study (BBCS). We used existing control data from four cohort studies already genotyped and subjected to rigorous quality control metrics: the European Prospective Investigation Into Cancer and Nutrition Study (EPIC), Womens Health Initiative (WHI), Health Professionals Follow-up Study (HPFS), Nurses Health Study (NHS), which have been a part of Cancer Genetic Markers of Susceptibility (CGEMS). Meta-analysis of NCI-GWAS1, NCI-GWAS2 and a previously reported GWAS TXBCS-GWAS along with taqman replication, identified two new loci: rs10936599 on 3q26.2 (P = 4.53 x 10(-9)) and rs907611 on 11p15.5 (P = 4.11 x 10(-8)). Two notable loci were also identified that approached genome-wide statistical significance: rs6104690 on 20p12.2 (P = 7.13 x 10(-7)) and rs4510656 on 6p22.3 (P = 6.98 X 10(-7)); these require further studies for confirmation (Figueroa J et al, Human Molecular Genetics, 2013).]]>
SUPPLEMENTARY INFORMATIONHistologically confirmed primary carcinoma of the urinary bladder, including carcinoma in situ (ICD-0-2 topography codes C67.0-C67.9 or ICD9 codes 188.1-188.9).]]>
Bladder cancer is a major public health problem with high disease management costs because of high recurrence of tumors requiring frequent screening and interventions (of particular relevant for early stage tumors). There are well-known epidemiologic factors that are associated with increased risk for bladder cancer: smoking and occupational exposure to aromatic amines, important clues for environmental, medication use, and lifestyle risk factors, as well as fluid balance and urine pH. The portfolio of established risk factors should provide opportunities to evaluate risk factors stratified by genotype and genetic factors within distinct exposure subgroups. There is also good evidence for a genetic component, given that previous studies have demonstrated reproducible associations with NAT2 and GSTM1 genotypes. Further, gene-environment interactions have been shown for smoking and specific NAT2 genotypes. The modest familial association has not yet been adequately explained but supports the need to search for genetic markers associated with bladder cancer. Together these observations provide a strong case for investigation of multi-genic associations as well as gene-environment interactions. Excellent information on clinical outcomes including survival and tumor recurrence is available for exploration of the influence of genetic variants on these outcomes, which could have potentially important clinical implications. Results from a GWAS leading to the identification of genetic makers could provide major insights into novel regions that regulate new mechanisms underlying bladder cancer pathogenesis. Findings from the GWAS could also provide etiological clues leading to the identification of additional modifiable factors that increase bladder cancer risk, recurrence and survival. The potential is great for advancing the understanding of the genetic contribution to bladder cancer, which could establish the foundation for developing novel approaches towards prevention while decreasing the burden of bladder cancer.]]>