ABSTRACT
BACKGROUND: The shared inherited genetic contribution to risk of different cancers is not fully known. In this study, we leverage results from 12 cancer genome-wide association studies (GWAS) to quantify pairwise genome-wide genetic correlations across cancers and identify novel cancer susceptibility loci. METHODS: We collected GWAS summary statistics for 12 solid cancers based on 376â759 participants with cancer and 532â864 participants without cancer of European ancestry. The included cancer types were breast, colorectal, endometrial, esophageal, glioma, head and neck, lung, melanoma, ovarian, pancreatic, prostate, and renal cancers. We conducted cross-cancer GWAS and transcriptome-wide association studies to discover novel cancer susceptibility loci. Finally, we assessed the extent of variant-specific pleiotropy among cancers at known and newly identified cancer susceptibility loci. RESULTS: We observed widespread but modest genome-wide genetic correlations across cancers. In cross-cancer GWAS and transcriptome-wide association studies, we identified 15 novel cancer susceptibility loci. Additionally, we identified multiple variants at 77 distinct loci with strong evidence of being associated with at least 2 cancer types by testing for pleiotropy at known cancer susceptibility loci. CONCLUSIONS: Overall, these results suggest that some genetic risk variants are shared among cancers, though much of cancer heritability is cancer-specific and thus tissue-specific. The increase in statistical power associated with larger sample sizes in cross-disease analysis allows for the identification of novel susceptibility regions. Future studies incorporating data on multiple cancer types are likely to identify additional regions associated with the risk of multiple cancer types.
Subject(s)
Genome-Wide Association Study , Neoplasms , Male , Humans , Genome-Wide Association Study/methods , Genetic Predisposition to Disease , Neoplasms/genetics , Risk Factors , Transcriptome , Polymorphism, Single NucleotideABSTRACT
BACKGROUND: Lynch syndrome (LS) screening guidelines originally recommended colonoscopy every 1 to 2 years, beginning between the ages of 20 and 25 years. Recent studies have questioned the benefits of these short screening intervals in preventing colorectal cancer (CRC). Our goal is to determine how colonoscopy screening intervals impact CRC in patients with LS. METHODS: We analyzed the demographics, screening practices, and outcomes of patients with LS identified through the clinic based Familial Gastrointestinal Cancer Registry at the Zane Cohen Centre, Sinai Health System, Toronto, Canada. RESULTS: A total of 429 patients with LS were identified with median follow-up of 9.2 years; 44 developed CRC. We found a positive trend between shorter screening intervals and the number of adenomas detected during colonoscopy. Any new adenoma detected at screening decreased 10-year CRC incidence by 11.3%. For MLH1 carriers, a screening interval of 1-2 years vs 2-3 years led to a 20-year cumulative CRC risk reduction of 28% and 14% in females and males, respectively. For MSH2 carriers, this risk reduction was 29% and 17%, respectively, and for male MSH6 carriers 18%. Individuals without any adenomas detected (53.4% of LS carriers) had an increased 20-year CRC risk of 25.7% and 57.2% for women and men, respectively, compared with those diagnosed with adenomas at screening. CONCLUSIONS: The recommended colonoscopy screening interval of 1-2 years is efficient at detecting adenomas and reducing CRC risk. The observation that 53.4% of LS patients never had an adenoma warrants further investigation about a possible adenoma-free pathway.
Subject(s)
Adenoma , Colorectal Neoplasms, Hereditary Nonpolyposis , Colorectal Neoplasms , Humans , Male , Female , Young Adult , Adult , Colorectal Neoplasms, Hereditary Nonpolyposis/diagnosis , Colorectal Neoplasms, Hereditary Nonpolyposis/epidemiology , Colorectal Neoplasms, Hereditary Nonpolyposis/genetics , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/epidemiology , Colorectal Neoplasms/prevention & control , Canada/epidemiology , Colonoscopy , Adenoma/diagnosis , Adenoma/epidemiology , Adenoma/prevention & control , RegistriesABSTRACT
OBJECTIVE: GATA6 is a key regulator of the classical phenotype in pancreatic ductal adenocarcinoma (PDAC). Low GATA6 expression associates with poor patient outcome. GATA4 is the second most expressed GATA factor in the pancreas. We assessed whether, and how, GATA4 contributes to PDAC phenotype and analysed the association of expression with outcome and response to chemotherapy. DESIGN: We analysed PDAC transcriptomic data, stratifying cases according to GATA4 and GATA6 expression and identified differentially expressed genes and pathways. The genome-wide distribution of GATA4 was assessed, as well as the effects of GATA4 knockdown. A multicentre tissue microarray study to assess GATA4 and GATA6 expression in samples (n=745) from patients with resectable was performed. GATA4 and GATA6 levels were dichotomised into high/low categorical variables; association with outcome was assessed using univariable and multivariable Cox regression models. RESULTS: GATA4 messenger RNA is enriched in classical, compared with basal-like tumours. We classified samples in 4 groups as high/low for GATA4 and GATA6. Reduced expression of GATA4 had a minor transcriptional impact but low expression of GATA4 enhanced the effects of GATA6 low expression. GATA4 and GATA6 display a partially overlapping genome-wide distribution, mainly at promoters. Reduced expression of both proteins in tumours was associated with the worst patient survival. GATA4 and GATA6 expression significantly decreased in metastases and negatively correlated with basal markers. CONCLUSIONS: GATA4 and GATA6 cooperate to maintain the classical phenotype. Our findings provide compelling rationale to assess their expression as biomarkers of poor prognosis and therapeutic response.
Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Humans , Pancreatic Neoplasms/pathology , Pancreas/pathology , Carcinoma, Pancreatic Ductal/pathology , Gene Expression Profiling , GATA6 Transcription Factor/genetics , GATA4 Transcription Factor/genetics , GATA4 Transcription Factor/metabolismABSTRACT
Background: Tumor hypoxia is theorized to contribute to the aggressive biology of pancreatic ductal adenocarcinoma (PDAC). We previously reported that hypoxia correlated with rapid tumor growth and metastasis in patient-derived xenografts. Anticipating a prognostic relevance of hypoxia in patient tumors, we developed protocols for automated semi-quantitative image analysis to provide an objective, observer-independent measure of hypoxia. We further validated this method which can reproducibly estimate pimonidazole-detectable hypoxia in a high-through put manner. Methods: We studied the performance of three automated image analysis platforms in scoring pimonidazole-detectable hypoxia in resected PDAC (n = 10) in a cohort of patients enrolled in PIMO-PANC. Multiple stained tumor sections were analyzed on three independent image-analysis platforms, Aperio Genie (AG), Definiens Tissue Studio (TS), and Definiens Developer (DD), which comprised of a customized rule set. Results: The output from Aperio Genie (AG) had good concordance with manual scoring, but the workflow was resource-intensive and not suited for high-throughput analysis. TS analysis had high levels of variability related to misclassification of cells class, while the customized rule set of DD had a high level of reliability with an intraclass coefficient of more than 85%. Discussion: This work demonstrates the feasibility of developing a robust, high-performance pipeline for an automated, quantitative scoring of pimonidazole-detectable hypoxia in patient tumors.
ABSTRACT
BACKGROUND: Laparoscopic liver resections for malignancy are increasing worldwide, and yet data from North America are lacking. We aimed to assess the long-term outcomes of patients undergoing laparoscopic liver resection and open liver resection as a treatment for hepatocellular carcinoma. METHODS: Patients undergoing liver resection for hepatocellular carcinoma between January 2008 and December 2019 were retrospectively studied. A propensity score matching was performed using patient demographics, laboratory parameters, etiology of liver disease, liver function, and tumor characteristics. Primary outcomes included overall survival and cumulative incidence of recurrence. Kaplan-Meier and competing risk cumulative incidence were used for survival analyses. Multivariable Cox regression and Fine-Gray proportional hazard regression were performed to determine hazard for death and recurrence, respectively. RESULTS: Three hundred and ninety-one patients were identified (laparoscopic liver resection: 110; open liver resection: 281). After propensity score matching, 149 patients remained (laparoscopic liver resection: 57; open liver resection: 92). There were no significant differences between groups with regard to extent of hepatectomy performed and tumor characteristics. The laparoscopic liver resection group experienced a lower proportion of ≥Clavien-Dindo grade III complications (14% vs 29%; P = .01). In the matched cohort, the 1-, 3-, and 5-year overall survival rate in the laparoscopic liver resection versus open liver resection group was 90.9%, 79.3%, 70.5% vs 91.3%, 88.5%, 83.1% (P = .26), and the cumulative incidence of recurrence 31.1%, 59.7%, 62.9% vs 18.9%, 40.6%, 49.2% (P = .06), respectively. CONCLUSION: This study represents the largest single institutional study from North America comparing long-term oncologic outcomes of laparoscopic liver resection and open liver resection as a treatment for primary hepatocellular carcinoma. The combination of reduced short-term complications and equivalent long-term oncologic outcomes favor the laparoscopic approach when feasible.
Subject(s)
Carcinoma, Hepatocellular , Laparoscopy , Liver Neoplasms , Disease-Free Survival , Hepatectomy/adverse effects , Humans , Laparoscopy/adverse effects , Length of Stay , Propensity Score , Retrospective Studies , Treatment OutcomeABSTRACT
BACKGROUND: While genome-wide association studies (GWAS) have identified germline variants influencing the risk of developing colorectal cancer (CRC), there has been limited examination of the possible role of inherited variation as a determinant of patient outcome. PATIENTS AND METHODS: We performed a GWAS for overall survival (OS) in 1926 patients with advanced CRC from the COIN and COIN-B clinical trials. For single nucleotide polymorphisms (SNPs) showing an association with OS (P < 1.0 × 10-5), we conducted sensitivity analyses based on the time from diagnosis to death and sought independent replications in 5675 patients from the Study of Colorectal Cancer in Scotland (SOCCS) and 16,964 patients from the International Survival Analysis in Colorectal cancer Consortium (ISACC). We analysed the Human Protein Atlas to determine if ERBB4 expression was associated with survival in 438 patients with colon adenocarcinomas. RESULTS: The most significant SNP associated with OS was rs79612564 in ERBB4 (hazard ratio [HR] = 1.24, 95% confidence interval [CI] = 1.16-1.32, P = 1.9 × 10-7). SNPs at 17 loci had suggestive associations for OS and all had similar effects on the time from diagnosis to death. No lead SNPs were independently replicated in the meta-analysis of all patients from SOCCS and ISACC. However, rs79612564 was significant in stage-IV patients from SOCCS (P = 2.1 × 10-2) but not ISACC (P = 0.89) and SOCCS combined with COIN and COIN-B attained genome-wide significance (P = 1.7 × 10-8). Patients with high ERBB4 expression in their colon adenocarcinomas had worse survival (HR = 1.50, 95% CI = 1.1-1.9, P = 4.6 × 10-2). CONCLUSIONS: Genetic and expression data support a potential role for rs79612564 in the receptor tyrosine kinase ERBB4 as a predictive biomarker of survival.
Subject(s)
Adenocarcinoma/genetics , Biomarkers, Tumor/genetics , Colorectal Neoplasms/genetics , Receptor, ErbB-4/genetics , Adenocarcinoma/mortality , Colorectal Neoplasms/mortality , Genome-Wide Association Study , Genotype , Humans , Polymorphism, Single NucleotideABSTRACT
OBJECTIVE: Germline pathogenic variants (PVs) in the DNA mismatch repair (MMR) genes and in the base excision repair gene MUTYH underlie hereditary colorectal cancer (CRC) and polyposis syndromes. We evaluated the robustness and discriminatory potential of tumour mutational signatures in CRCs for identifying germline PV carriers. DESIGN: Whole-exome sequencing of formalin-fixed paraffin-embedded (FFPE) CRC tissue was performed on 33 MMR germline PV carriers, 12 biallelic MUTYH germline PV carriers, 25 sporadic MLH1 methylated MMR-deficient CRCs (MMRd controls) and 160 sporadic MMR-proficient CRCs (MMRp controls) and included 498 TCGA CRC tumours. COSMIC V3 single base substitution (SBS) and indel (ID) mutational signatures were assessed for their ability to differentiate CRCs that developed in carriers from non-carriers. RESULTS: The combination of mutational signatures SBS18 and SBS36 contributing >30% of a CRC's signature profile was able to discriminate biallelic MUTYH carriers from all other non-carrier control CRCs with 100% accuracy (area under the curve (AUC) 1.0). SBS18 and SBS36 were associated with specific MUTYH variants p.Gly396Asp (p=0.025) and p.Tyr179Cys (p=5×10-5), respectively. The combination of ID2 and ID7 could discriminate the 33 MMR PV carrier CRCs from the MMRp control CRCs (AUC 0.99); however, SBS and ID signatures, alone or in combination, could not provide complete discrimination (AUC 0.79) between CRCs from MMR PV carriers and sporadic MMRd controls. CONCLUSION: Assessment of SBS and ID signatures can discriminate CRCs from biallelic MUTYH carriers and MMR PV carriers from non-carriers with high accuracy, demonstrating utility as a potential diagnostic and variant classification tool.
Subject(s)
Adenomatous Polyposis Coli/genetics , Colorectal Neoplasms/genetics , DNA Glycosylases , Germ-Line Mutation , MutL Protein Homolog 1 , DNA Mismatch Repair , Female , Genetic Predisposition to Disease , Heterozygote , Humans , Male , Middle Aged , Syndrome , Exome SequencingABSTRACT
BACKGROUND: /Objective. To determine the outcomes of a non-operative management approach for sporadic, small, non-functional pancreatic neuroendocrine tumours. METHODS: A retrospective chart review of patients with non-functional pancreatic neuroendocrine tumours initially managed non-operatively at a single institution was performed. Patients were identified through a search of radiologic reports, and individuals with ≥2 cross-sectional imaging studies performed >6 months apart from Jan. 1, 2000 to Dec. 31, 2013 were included. Data on tumour size, radiologic characteristics at diagnosis, interval radiologic growth, and surgical outcomes were recorded. RESULTS: Over the thirteen-year study period, 95 patients met inclusion criteria and were followed radiologically for a median of 36 months (18-69 months). Median initial tumour size on first imaging was 14.0â¯mm (IQR 10-19â¯mm). Median overall tumour growth rate was 0.03â¯mm/month (IQR: 0.00-0.14â¯mm/month). There was no significant relationship between initial tumour size and growth rate for tumours ≤ 2â¯cm or for lesions between 2 and 4â¯cm. Thirteen (14%) patients initially managed non-operatively underwent resection during the follow-up period. Reasons for surgery included interval tumour growth, patient anxiety or preference, or diagnostic uncertainty. Median time to surgery was 14 months (IQR 8-19 months). No patients progressed beyond resectability or developed metastatic disease during the observation period. CONCLUSION: For patients with sporadic, small, non-functional pancreatic neuroendocrine tumours, radiologic surveillance appears to be a safe initial approach to management.
Subject(s)
Neuroendocrine Tumors/pathology , Neuroendocrine Tumors/therapy , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/therapy , Aged , Female , Humans , Male , Middle Aged , Retrospective StudiesABSTRACT
PURPOSE: Constitutional mismatch repair deficiency (CMMRD) is a highly penetrant cancer predisposition syndrome caused by biallelic mutations in mismatch repair (MMR) genes. As several cancer syndromes are clinically similar, accurate diagnosis is critical to cancer screening and treatment. As genetic diagnosis is confounded by 15 or more pseudogenes and variants of uncertain significance, a robust diagnostic assay is urgently needed. We sought to determine whether an assay that directly measures MMR activity could accurately diagnose CMMRD. PATIENTS AND METHODS: In vitro MMR activity was quantified using a 3'-nicked G-T mismatched DNA substrate, which requires MSH2-MSH6 and MLH1-PMS2 for repair. We quantified MMR activity from 20 Epstein-Barr virus-transformed lymphoblastoid cell lines from patients with confirmed CMMRD. We also tested 20 lymphoblastoid cell lines from patients who were suspected for CMMRD. We also characterized MMR activity from patients with neurofibromatosis type 1, Li-Fraumeni syndrome, polymerase proofreading-associated cancer syndrome, and Lynch syndrome. RESULTS: All CMMRD cell lines had low MMR activity (n = 20; mean, 4.14 ± 1.56%) relative to controls (n = 6; mean, 44.00 ± 8.65%; P < .001). Repair was restored by complementation with the missing protein, which confirmed MMR deficiency. All cases of patients with suspected CMMRD were accurately diagnosed. Individuals with Lynch syndrome (n = 28), neurofibromatosis type 1 (n = 5), Li-Fraumeni syndrome (n = 5), and polymerase proofreading-associated cancer syndrome (n = 3) had MMR activity that was comparable to controls. To accelerate testing, we measured MMR activity directly from fresh lymphocytes, which yielded results in 8 days. CONCLUSION: On the basis of the current data set, the in vitro G-T repair assay was able to diagnose CMMRD with 100% specificity and sensitivity. Rapid diagnosis before surgery in non-neoplastic tissues could speed proper therapeutic management.
Subject(s)
Biomarkers, Tumor/genetics , Brain Neoplasms/diagnosis , Brain Neoplasms/genetics , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/genetics , DNA Mismatch Repair , DNA Repair Enzymes/genetics , Genetic Testing , Mutation , Neoplastic Syndromes, Hereditary/diagnosis , Neoplastic Syndromes, Hereditary/genetics , Biomarkers, Tumor/metabolism , Brain Neoplasms/metabolism , Case-Control Studies , Cell Line, Tumor , Colorectal Neoplasms/metabolism , DNA Repair Enzymes/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Genetic Predisposition to Disease , Humans , Mismatch Repair Endonuclease PMS2/genetics , Mismatch Repair Endonuclease PMS2/metabolism , MutL Protein Homolog 1/genetics , MutL Protein Homolog 1/metabolism , MutS Homolog 2 Protein/genetics , MutS Homolog 2 Protein/metabolism , Neoplastic Syndromes, Hereditary/metabolism , Phenotype , Predictive Value of TestsABSTRACT
BACKGROUND: Observational studies have associated adiposity with an increased risk of colorectal cancer (CRC). However, such studies do not establish a causal relationship. To minimise bias from confounding we performed a Mendelian randomisation (MR) analysis to examine the relationship between adiposity and CRC. METHODS: We used SNPs associated with adult body mass index (BMI), waist-hip ratio (WHR), childhood obesity and birth weight as instrumental variables in a MR analysis of 9254 CRC cases and 18 386 controls. RESULTS: In the MR analysis, the odds ratios (ORs) of CRC risk per unit increase in BMI, WHR and childhood obesity were 1.23 (95% CI: 1.02-1.49, P=0.033), 1.59 (95% CI: 1.08-2.34, P=0.019) and 1.07 (95% CI: 1.03-1.13, P=0.018), respectively. There was no evidence for association between birth weight and CRC (OR=1.22, 95% CI: 0.89-1.67, P=0.22). Combining these data with a concurrent MR-based analysis for BMI and WHR with CRC risk (totalling to 18 190 cases, 27 617 controls) provided increased support, ORs for BMI and WHR were 1.26 (95% CI: 1.10-1.44, P=7.7 × 10(-4)) and 1.40 (95% CI: 1.14-1.72, P=1.2 × 10(-3)), respectively. CONCLUSIONS: These data provide further evidence for a strong causal relationship between adiposity and the risk of developing CRC highlighting the urgent need for prevention and treatment of adiposity.
Subject(s)
Adiposity/genetics , Colorectal Neoplasms/complications , Adult , Colorectal Neoplasms/genetics , Female , Genome-Wide Association Study , Humans , Male , Middle Aged , Polymorphism, Single Nucleotide , Random AllocationABSTRACT
To identify new risk loci for colorectal cancer (CRC), we conducted a meta-analysis of seven genome-wide association studies (GWAS) with independent replication, totalling 13 656 CRC cases and 21 667 controls of European ancestry. The combined analysis identified a new risk association for CRC at 2q35 marked by rs992157 (P = 3.15 × 10-8, odds ratio = 1.10, 95% confidence interval = 1.06-1.13), which is intronic to PNKD (paroxysmal non-kinesigenic dyskinesia) and TMBIM1 (transmembrane BAX inhibitor motif containing 1). Intriguingly this susceptibility single-nucleotide polymorphism (SNP) is in strong linkage disequilibrium (r2 = 0.90, D' = 0.96) with the previously discovered GWAS SNP rs2382817 for inflammatory bowel disease (IBD). Following on from this observation we examined for pleiotropy, or shared genetic susceptibility, between CRC and the 200 established IBD risk loci, identifying an additional 11 significant associations (false discovery rate [FDR]) < 0.05). Our findings provide further insight into the biological basis of inherited genetic susceptibility to CRC, and identify risk factors that may influence the development of both CRC and IBD.
Subject(s)
Apoptosis Regulatory Proteins/genetics , Colorectal Neoplasms/genetics , Inflammatory Bowel Diseases/genetics , Membrane Proteins/genetics , Muscle Proteins/genetics , Asian People , Colorectal Neoplasms/pathology , Female , Genetic Pleiotropy , Genetic Predisposition to Disease , Genome-Wide Association Study , Humans , Inflammatory Bowel Diseases/pathology , Linkage Disequilibrium , Male , Polymorphism, Single Nucleotide , Risk Factors , White PeopleABSTRACT
BACKGROUND: In November 2001, genetic testing for Lynch syndrome (LS) was introduced by the Ministry of Health and Long-Term Care (MOH) in Ontario for individuals at high risk for LS cancers according to either tumor immunohistochemistry staining or their family history. This article describes the outcomes of the program and makes recommendations for improving it and informing other public health care programs. METHODS: Subjects were referred for molecular testing of the mismatch repair (MMR) genes MutL homolog 1, MutS homolog 2, and MutS homolog 6 if they met 1 of 7 MOH criteria. Testing was conducted from January 2001 to March 2015 at the Molecular Diagnostic Laboratory of Mount Sinai Hospital in Toronto. RESULTS: A total of 1452 subjects were tested. Of the 662 subjects referred for testing because their tumor was immunodeficient for 1 or more of the MMR genes, 251 (37.9%) carried a germline mutation. In addition, 597 subjects were tested for a known family mutation, and 298 (49.9%) were positive; 189 of these 298 subjects (63.4%) were affected with cancer at the time of testing. An additional 193 subjects were referred because of a family history of LS, and 34 of these (17.6%) had a mutation identified. CONCLUSIONS: These results indicate that the provincial criteria are useful in identifying LS carriers after an MMR-deficient tumor is identified. Placing greater emphasis on testing unaffected relatives in families with a known mutation may identify more unaffected carriers and facilitate primary prevention in those individuals. Cancer 2016;122:1672-9. © 2016 American Cancer Society.
Subject(s)
Colorectal Neoplasms, Hereditary Nonpolyposis/genetics , DNA Mismatch Repair , Genetic Testing/methods , Germ-Line Mutation , Adolescent , Adult , Aged , Colorectal Neoplasms, Hereditary Nonpolyposis/diagnosis , DNA-Binding Proteins/genetics , Family Health , Female , Heterozygote , Humans , Male , Microsatellite Instability , Middle Aged , MutL Protein Homolog 1/genetics , MutS Homolog 2 Protein/genetics , Ontario , Program Evaluation , Young AdultABSTRACT
High-risk mutations in several genes predispose to both colorectal cancer (CRC) and endometrial cancer (EC). We therefore hypothesised that some lower-risk genetic variants might also predispose to both CRC and EC. Using CRC and EC genome-wide association series, totalling 13,265 cancer cases and 40,245 controls, we found that the protective allele [G] at one previously-identified CRC polymorphism, rs2736100 near TERT, was associated with EC risk (odds ratio (OR) = 1.08, P = 0.000167); this polymorphism influences the risk of several other cancers. A further CRC polymorphism near TERC also showed evidence of association with EC (OR = 0.92; P = 0.03). Overall, however, there was no good evidence that the set of CRC polymorphisms was associated with EC risk, and neither of two previously-reported EC polymorphisms was associated with CRC risk. A combined analysis revealed one genome-wide significant polymorphism, rs3184504, on chromosome 12q24 (OR = 1.10, P = 7.23 × 10(-9)) with shared effects on CRC and EC risk. This polymorphism, a missense variant in the gene SH2B3, is also associated with haematological and autoimmune disorders, suggesting that it influences cancer risk through the immune response. Another polymorphism, rs12970291 near gene TSHZ1, was associated with both CRC and EC (OR = 1.26, P = 4.82 × 10(-8)), with the alleles showing opposite effects on the risks of the two cancers.
Subject(s)
Colorectal Neoplasms/genetics , Endometrial Neoplasms/genetics , Genetic Predisposition to Disease , Genome-Wide Association Study , Homeodomain Proteins/genetics , Neoplasm Proteins/genetics , Polymorphism, Genetic , Proteins/genetics , Adaptor Proteins, Signal Transducing , Alleles , Female , Humans , Intracellular Signaling Peptides and Proteins , Male , Repressor ProteinsABSTRACT
Genome-wide association studies (GWAS) of colorectal cancer (CRC) have identified 23 susceptibility loci thus far. Analyses of previously conducted GWAS indicate additional risk loci are yet to be discovered. To identify novel CRC susceptibility loci, we conducted a new GWAS and performed a meta-analysis with five published GWAS (totalling 7,577 cases and 9,979 controls of European ancestry), imputing genotypes utilising the 1000 Genomes Project. The combined analysis identified new, significant associations with CRC at 1p36.2 marked by rs72647484 (minor allele frequency [MAF] = 0.09) near CDC42 and WNT4 (P = 1.21 × 10(-8), odds ratio [OR] = 1.21 ) and at 16q24.1 marked by rs16941835 (MAF = 0.21, P = 5.06 × 10(-8); OR = 1.15) within the long non-coding RNA (lncRNA) RP11-58A18.1 and ~500 kb from the nearest coding gene FOXL1. Additionally we identified a promising association at 10p13 with rs10904849 intronic to CUBN (MAF = 0.32, P = 7.01 × 10(-8); OR = 1.14). These findings provide further insights into the genetic and biological basis of inherited genetic susceptibility to CRC. Additionally, our analysis further demonstrates that imputation can be used to exploit GWAS data to identify novel disease-causing variants.
Subject(s)
Biomarkers, Tumor/genetics , Colorectal Neoplasms/genetics , Genetic Predisposition to Disease , Chromosome Mapping , Female , Forkhead Transcription Factors/genetics , Gene Frequency/genetics , Genome-Wide Association Study , Humans , Male , Middle Aged , Polymorphism, Single Nucleotide/genetics , Receptors, Cell Surface/geneticsABSTRACT
Evidence on the association between vitamin D status and pancreatic cancer risk is inconsistent. This inconsistency may be partially attributable to variation in vitamin D regulating genes. We selected 11 vitamin D-related genes (GC, DHCR7, CYP2R1, VDR, CYP27B1, CYP24A1, CYP27A1, RXRA, CRP2, CASR and CUBN) totaling 213 single nucleotide polymorphisms (SNPs), and examined associations with pancreatic adenocarcinoma. Our study included 3,583 pancreatic cancer cases and 7,053 controls from the genome-wide association studies of pancreatic cancer PanScans-I-III. We used the Adaptive Joint Test and the Adaptive Rank Truncated Product statistic for pathway and gene analyses, and unconditional logistic regression for SNP analyses, adjusting for age, sex, study and population stratification. We examined effect modification by circulating vitamin D concentration (≤50, >50 nmol/L) for the most significant SNPs using a subset of cohort cases (n = 713) and controls (n = 878). The vitamin D metabolic pathway was not associated with pancreatic cancer risk (p = 0.830). Of the individual genes, none were associated with pancreatic cancer risk at a significance level of p<0.05. SNPs near the VDR (rs2239186), LRP2 (rs4668123), CYP24A1 (rs2762932), GC (rs2282679), and CUBN (rs1810205) genes were the top SNPs associated with pancreatic cancer (p-values 0.008-0.037), but none were statistically significant after adjusting for multiple comparisons. Associations between these SNPs and pancreatic cancer were not modified by circulating concentrations of vitamin D. These findings do not support an association between vitamin D-related genes and pancreatic cancer risk. Future research should explore other pathways through which vitamin D status might be associated with pancreatic cancer risk.
Subject(s)
Biomarkers, Tumor/genetics , Genetic Predisposition to Disease , Metabolic Networks and Pathways/genetics , Pancreatic Neoplasms/blood , Pancreatic Neoplasms/genetics , Polymorphism, Single Nucleotide/genetics , Vitamin D/blood , Case-Control Studies , Cohort Studies , Follow-Up Studies , Genotype , Humans , Risk Factors , Vitamin D/genetics , Vitamin D-Binding Protein/genetics , Vitamins/blood , Vitamins/geneticsABSTRACT
To identify common variants influencing colorectal cancer (CRC) risk, we performed a meta-analysis of five genome-wide association studies, comprising 5626 cases and 7817 controls of European descent. We conducted replication of top ranked single nucleotide polymorphisms (SNPs) in additional series totalling 14 037 cases and 15 937 controls, identifying a new CRC risk locus at 10q24.2 [rs1035209; odds ratio (OR) = 1.13, P = 4.54 × 10(-11)]. We also performed meta-analysis of our studies, with previously published data, of several recently purported CRC risk loci. We failed to find convincing evidence for a previously reported genome-wide association at rs11903757 (2q32.3). Of the three additional loci for which evidence of an association in Europeans has been previously described we failed to show an association between rs59336 (12q24.21) and CRC risk. However, for the other two SNPs, our analyses demonstrated new, formally significant associations with CRC. These are rs3217810 intronic in CCND2 (12p13.32; OR = 1.19, P = 2.16 × 10(-10)) and rs10911251 near LAMC1 (1q25.3; OR = 1.09, P = 1.75 × 10(-8)). Additionally, we found some evidence to support a relationship between, rs647161, rs2423297 and rs10774214 and CRC risk originally identified in East Asians in our European datasets. Our findings provide further insights into the genetic and biological basis of inherited genetic susceptibility to CRC.
Subject(s)
Colorectal Neoplasms/genetics , Genetic Loci/genetics , Genetic Predisposition to Disease , Genome-Wide Association Study , Asian People/genetics , Female , Humans , Male , Middle Aged , Odds Ratio , Polymorphism, Single Nucleotide/genetics , Quantitative Trait Loci/genetics , White People/geneticsABSTRACT
Early-onset breast cancer (EOBC) causes substantial loss of life and productivity, creating a major burden among women worldwide. We analyzed 1,265,548 Hapmap3 single-nucleotide polymorphisms (SNP) among a discovery set of 3,523 EOBC incident cases and 2,702 population control women ages ≤ 51 years. The SNPs with smallest P values were examined in a replication set of 3,470 EOBC cases and 5,475 control women. We also tested EOBC association with 19,684 genes by annotating each gene with putative functional SNPs, and then combining their P values to obtain a gene-based P value. We examined the gene with smallest P value for replication in 1,145 breast cancer cases and 1,142 control women. The combined discovery and replication sets identified 72 new SNPs associated with EOBC (P < 4 × 10(-8)) located in six genomic regions previously reported to contain SNPs associated largely with later-onset breast cancer (LOBC). SNP rs2229882 and 10 other SNPs on chromosome 5q11.2 remained associated (P < 6 × 10(-4)) after adjustment for the strongest published SNPs in the region. Thirty-two of the 82 currently known LOBC SNPs were associated with EOBC (P < 0.05). Low power is likely responsible for the remaining 50 unassociated known LOBC SNPs. The gene-based analysis identified an association between breast cancer and the phosphofructokinase-muscle (PFKM) gene on chromosome 12q13.11 that met the genome-wide gene-based threshold of 2.5 × 10(-6). In conclusion, EOBC and LOBC seem to have similar genetic etiologies; the 5q11.2 region may contain multiple distinct breast cancer loci; and the PFKM gene region is worthy of further investigation. These findings should enhance our understanding of the etiology of breast cancer.
Subject(s)
Biomarkers, Tumor/genetics , Breast Neoplasms/enzymology , Breast Neoplasms/genetics , Phosphofructokinase-1, Muscle Type/genetics , Breast Neoplasms/epidemiology , Case-Control Studies , Female , Genetic Predisposition to Disease , Genome-Wide Association Study , Humans , Middle Aged , Polymorphism, Single NucleotideABSTRACT
AIMS: Prophylactic hysterectomy with bilateral salpingo-oophorectomy is being increasingly undertaken in patients with Lynch syndrome (LS). The pathological features in such specimens are not well described and, unlike the SEE-FIM protocol for salpingo-oophorectomy specimens in BRCA1/2 mutation carriers and the gastrectomy grossing protocols for patients with CDH1 (E-cadherin) mutations, guidelines have not been devised for the grossing of prophylactic gynaecological specimens from LS patients. We aimed to review the pathological findings in a series of prophylactic gynaecological specimens from LS patients and develop guidelines for the grossing of these specimens. METHODS AND RESULTS: We reviewed the pathological findings in 25 prophylactic gynaecological specimens from LS patients and audited the grossing protocols in different centres across Ontario, Canada. We found a 32% incidence of endometrial carcinoma or a precursor lesion; the two endometrial cancers identified were low-grade, low-stage endometrioid adenocarcinomas. To address the absence of guidelines for pathological examination, we undertook a literature review of gynaecological malignancies and incidental findings in prophylactic specimens in LS patients. CONCLUSION: We provide recommendations regarding the grossing of such specimens which includes in-toto examination of the lower uterine segment, endometrium, ovaries and fallopian tubes with representative sampling of the cervix.