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1.
Nat Commun ; 13(1): 3254, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35668106

RESUMO

Carriers of germline biallelic pathogenic variants in the MUTYH gene have a high risk of colorectal cancer. We test 5649 colorectal cancers to evaluate the discriminatory potential of a tumor mutational signature specific to MUTYH for identifying biallelic carriers and classifying variants of uncertain clinical significance (VUS). Using a tumor and matched germline targeted multi-gene panel approach, our classifier identifies all biallelic MUTYH carriers and all known non-carriers in an independent test set of 3019 colorectal cancers (accuracy = 100% (95% confidence interval 99.87-100%)). All monoallelic MUTYH carriers are classified with the non-MUTYH carriers. The classifier provides evidence for a pathogenic classification for two VUS and a benign classification for five VUS. Somatic hotspot mutations KRAS p.G12C and PIK3CA p.Q546K are associated with colorectal cancers from biallelic MUTYH carriers compared with non-carriers (p = 2 × 10-23 and p = 6 × 10-11, respectively). Here, we demonstrate the potential application of mutational signatures to tumor sequencing workflows to improve the identification of biallelic MUTYH carriers.


Assuntos
Neoplasias Colorretais , DNA Glicosilases , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , DNA Glicosilases/genética , Análise Mutacional de DNA , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Heterozigoto , Humanos , Mutação
2.
Cancers (Basel) ; 14(11)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35681745

RESUMO

Cumulus, Altocumulus, and Cirrocumulus are measures of mammographic density defined at increasing pixel brightness thresholds, which, when converted to mammogram risk scores (MRSs), predict breast cancer risk. Twin and family studies suggest substantial variance in the MRSs could be explained by genetic factors. For 2559 women aged 30 to 80 years (mean 54 years), we measured the MRSs from digitized film mammograms and estimated the associations of the MRSs with a 313-SNP breast cancer polygenic risk score (PRS) and 202 individual SNPs associated with breast cancer risk. The PRS was weakly positively correlated (correlation coefficients ranged 0.05-0.08; all p < 0.04) with all the MRSs except the Cumulus-white MRS based on the "white but not bright area" (correlation coefficient = 0.04; p = 0.06). After adjusting for its association with the Altocumulus MRS, the PRS was not associated with the Cumulus MRS. There were MRS associations (Bonferroni-adjusted p < 0.04) with one SNP in the ATXN1 gene and nominally with some ESR1 SNPs. Less than 1% of the variance of the MRSs is explained by the genetic markers currently known to be associated with breast cancer risk. Discovering the genetic determinants of the bright, not white, regions of the mammogram could reveal substantial new genetic causes of breast cancer.

3.
Implement Sci ; 17(1): 31, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35550164

RESUMO

BACKGROUND: We developed a colorectal cancer risk prediction tool ('CRISP') to provide individualised risk-based advice for colorectal cancer screening. Using known environmental, behavioural, and familial risk factors, CRISP was designed to facilitate tailored screening advice to patients aged 50 to 74 years in general practice. In parallel to a randomised controlled trial of the CRISP tool, we developed and evaluated an evidence-based implementation strategy. METHODS: Qualitative methods were used to explore the implementation of CRISP in general practice. Using one general practice in regional Victoria, Australia, as a 'laboratory', we tested ways to embed CRISP into routine clinical practice. General practitioners, nurses, and operations manager co-designed the implementation methods with researchers, focussing on existing practice processes that would be sustainable. Researchers interviewed the staff regularly to assess the successfulness of the strategies employed, and implementation methods were adapted throughout the study period in response to feedback from qualitative interviews. The Consolidated Framework for Implementation Research (CFIR) underpinned the development of the interview guide and intervention strategy. Coding was inductive and themes were developed through consensus between the authors. Emerging themes were mapped onto the CFIR domains and a fidelity checklist was developed to ensure CRISP was being used as intended. RESULTS: Between December 2016 and September 2019, 1 interviews were conducted, both face-to-face and via videoconferencing (Zoom). All interviews were transcribed verbatim and coded. Themes were mapped onto the following CFIR domains: (1) 'characteristics of the intervention': CRISP was valued but time consuming; (2) 'inner setting': the practice was open to changing systems; 3. 'outer setting': CRISP helped facilitate screening; (4) 'individual characteristics': the practice staff were adaptable and able to facilitate adoption of new clinical processes; and (5) 'processes': fidelity checking, and education was important. CONCLUSIONS: These results describe a novel method for exploring implementation strategies for a colorectal cancer risk prediction tool in the context of a parallel RCT testing clinical efficacy. The study identified successful and unsuccessful implementation strategies using an adaptive methodology over time. This method emphasised the importance of co-design input to make an intervention like CRISP sustainable for use in other practices and with other risk tools.


Assuntos
Neoplasias Colorretais , Clínicos Gerais , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Humanos , Atenção Primária à Saúde/métodos , Pesquisa Qualitativa , Vitória
4.
J Natl Cancer Inst ; 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35512400

RESUMO

BACKGROUND: The use of menopausal hormone therapy (MHT) may interact with genetic variants to influence colorectal cancer (CRC) risk. METHODS: We conducted a genome-wide gene-environment interaction between single nucleotide polymorphisms and the use of any MHT, estrogen-only, and combined estrogen-progestogen therapy with CRC risk, among 28,486 postmenopausal women (11,519 cases and 16,967 controls) from 38 studies, using logistic regression, two-step method, and 2- or 3-degree-of-freedom (d.f.) joint test. A set-based score test was applied for rare genetic variants. RESULTS: The use of any MHT, estrogen-only and estrogen-progestogen were associated with a reduced CRC risk [odds ratio (OR) with 95% confidence interval (95% CI) of 0.71 (0.64-0.78), 0.65 (0.53-0.79), and 0.73 (0.59-0.90), respectively]. The two-step method identified a statistically significant interaction between a GRIN2B variant rs117868593 and MHT use, whereby MHT-associated CRC risk was significantly reduced in women with the GG genotype [0.68 (0.64-0.72)] but not within strata of GC or CC genotypes. A statistically significant interaction between a DCBLD1 intronic variant at 6q22.1 (rs10782186) and MHT use was identified by the 2-d.f. joint test. The MHT-associated CRC risk was reduced with increasing number of rs10782186-C alleles, showing ORs of 0.78 (0.70-0.87) for TT, 0.68 (0.63-0.73) for TC, and 0.66 (0.60-0.74) for CC genotypes. In addition, five genes in rare variant analysis showed suggestive interactions with MHT (two-sided P < 1.2x10-4). CONCLUSION: Genetic variants that modify the association between MHT and CRC risk were identified, offering new insights into pathways of CRC carcinogenesis and potential mechanisms involved.

5.
Genet Med ; 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35616648

RESUMO

PURPOSE: Heritable pathogenic variants in the DNA mismatch repair (MMR) pathway cause Lynch syndrome, a condition that significantly increases risk of colorectal and other cancers. At least half of individuals tested using gene panel sequencing have a variant of uncertain significance or no variant identified leading to no diagnosis. To fill this diagnostic gap, we developed Cancer Risk C (CR-C), a flow variant assay test. METHODS: In response to treatment with an alkylating agent, individual assays of the nuclear translocation of MLH1, MSH2, BARD1, PMS2, and BRCA2 proteins and the nuclear phosphorylation of the ATM and ATR proteins distinguished pathogenic/likely pathogenic (P/LP) from benign/likely benign variants in MMR genes. RESULTS: A risk classification score based on MLH1, MSH2, and ATR assays was 100% sensitive and 98% specific. Causality of MMR P/LP variants was shown through gene editing and rescue. In individuals with suspected Lynch syndrome but no P/LP, CR-C identified most (73%) as having germline MMR defects. Direct comparison of CR-C on matched blood samples and lymphoblastoid cell lines yielded comparable results (r2 > 0.9). CONCLUSION: For identifying germline MMR defects, CR-C provides augmentation to traditional panel sequencing through greater accuracy, shorter turnaround time (48 hours), and performance on blood with minimal sample handling.

6.
Cancer Epidemiol Biomarkers Prev ; 31(5): 1077-1089, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35438744

RESUMO

BACKGROUND: Currently known associations between common genetic variants and colorectal cancer explain less than half of its heritability of 25%. As alcohol consumption has a J-shape association with colorectal cancer risk, nondrinking and heavy drinking are both risk factors for colorectal cancer. METHODS: Individual-level data was pooled from the Colon Cancer Family Registry, Colorectal Transdisciplinary Study, and Genetics and Epidemiology of Colorectal Cancer Consortium to compare nondrinkers (≤1 g/day) and heavy drinkers (>28 g/day) with light-to-moderate drinkers (1-28 g/day) in GxE analyses. To improve power, we implemented joint 2df and 3df tests and a novel two-step method that modifies the weighted hypothesis testing framework. We prioritized putative causal variants by predicting allelic effects using support vector machine models. RESULTS: For nondrinking as compared with light-to-moderate drinking, the hybrid two-step approach identified 13 significant SNPs with pairwise r2 > 0.9 in the 10q24.2/COX15 region. When stratified by alcohol intake, the A allele of lead SNP rs2300985 has a dose-response increase in risk of colorectal cancer as compared with the G allele in light-to-moderate drinkers [OR for GA genotype = 1.11; 95% confidence interval (CI), 1.06-1.17; OR for AA genotype = 1.22; 95% CI, 1.14-1.31], but not in nondrinkers or heavy drinkers. Among the correlated candidate SNPs in the 10q24.2/COX15 region, rs1318920 was predicted to disrupt an HNF4 transcription factor binding motif. CONCLUSIONS: Our study suggests that the association with colorectal cancer in 10q24.2/COX15 observed in genome-wide association study is strongest in nondrinkers. We also identified rs1318920 as the putative causal regulatory variant for the region. IMPACT: The study identifies multifaceted evidence of a possible functional effect for rs1318920.


Assuntos
Neoplasias Colorretais , Estudo de Associação Genômica Ampla , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/genética , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Humanos , Polimorfismo de Nucleotídeo Único , Fatores de Risco
7.
Int J Cancer ; 151(3): 348-360, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35383926

RESUMO

Diabetes is an established risk factor for colorectal cancer. However, colorectal cancer is a heterogeneous disease and it is not well understood whether diabetes is more strongly associated with some tumor molecular subtypes than others. A better understanding of the association between diabetes and colorectal cancer according to molecular subtypes could provide important insights into the biology of this association. We used data on lifestyle and clinical characteristics from the Colorectal Cancer Family Registry (CCFR) and the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), including 9756 colorectal cancer cases (with tumor marker data) and 9985 controls, to evaluate associations between reported diabetes and risk of colorectal cancer according to molecular subtypes. Tumor markers included BRAF and KRAS mutations, microsatellite instability and CpG island methylator phenotype. In the multinomial logistic regression model, comparing colorectal cancer cases to cancer-free controls, diabetes was positively associated with colorectal cancer regardless of subtype. The highest OR estimate was found for BRAF-mutated colorectal cancer, n = 1086 (ORfully adj : 1.67, 95% confidence intervals [CI]: 1.36-2.05), with an attenuated association observed between diabetes and colorectal cancer without BRAF-mutations, n = 7959 (ORfully adj : 1.33, 95% CI: 1.19-1.48). In the case only analysis, BRAF-mutation was differentially associated with diabetes (Pdifference  = .03). For the other markers, associations with diabetes were similar across tumor subtypes. In conclusion, our study confirms the established association between diabetes and colorectal cancer risk, and suggests that it particularly increases the risk of BRAF-mutated tumors.


Assuntos
Neoplasias Colorretais , Diabetes Mellitus , Biomarcadores Tumorais/genética , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Ilhas de CpG/genética , Metilação de DNA , Diabetes Mellitus/genética , Humanos , Instabilidade de Microssatélites , Mutação , Fenótipo , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética
8.
Cancers (Basel) ; 14(6)2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35326633

RESUMO

Cumulus, Cumulus-percent, Altocumulus, Cirrocumulus, and Cumulus-white are mammogram risk scores (MRSs) for breast cancer based on mammographic density defined in effect by different levels of pixel brightness and adjusted for age and body mass index. We measured these MRS from digitized film mammograms for 593 monozygotic (MZ) and 326 dizygotic (DZ) female twin pairs and 1592 of their sisters. We estimated the correlations in relatives (r) and the proportion of variance due to genetic factors (heritability) using the software FISHER and predicted the familial risk ratio (FRR) associated with each MRS. The ρ estimates ranged from: 0.41 to 0.60 (standard error [SE] 0.02) for MZ pairs, 0.16 to 0.26 (SE 0.05) for DZ pairs, and 0.19 to 0.29 (SE 0.02) for sister pairs (including pairs of a twin and her non-twin sister), respectively. Heritability estimates were 39% to 69% under the classic twin model and 36% to 56% when allowing for shared non-genetic factors specific to MZ pairs. The FRRs were 1.08 to 1.17. These MRSs are substantially familial, due mostly to genetic factors that explain one-quarter to one-half as much of the familial aggregation of breast cancer that is explained by the current best polygenic risk score.

9.
Cancer Epidemiol Biomarkers Prev ; 31(6): 1216-1226, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35266989

RESUMO

BACKGROUND: The etiology of colorectal cancer is not fully understood. METHODS: Using genetic variants and metabolomics data including 217 metabolites from the Framingham Heart Study (n = 1,357), we built genetic prediction models for circulating metabolites. Models with prediction R2 > 0.01 (Nmetabolite = 58) were applied to predict levels of metabolites in two large consortia with a combined sample size of approximately 46,300 cases and 59,200 controls of European and approximately 21,700 cases and 47,400 controls of East Asian (EA) descent. Genetically predicted levels of metabolites were evaluated for their associations with colorectal cancer risk in logistic regressions within each racial group, after which the results were combined by meta-analysis. RESULTS: Of the 58 metabolites tested, 24 metabolites were significantly associated with colorectal cancer risk [Benjamini-Hochberg FDR (BH-FDR) < 0.05] in the European population (ORs ranged from 0.91 to 1.06; P values ranged from 0.02 to 6.4 × 10-8). Twenty one of the 24 associations were replicated in the EA population (ORs ranged from 0.26 to 1.69, BH-FDR < 0.05). In addition, the genetically predicted levels of C16:0 cholesteryl ester was significantly associated with colorectal cancer risk in the EA population only (OREA: 1.94, 95% CI, 1.60-2.36, P = 2.6 × 10-11; OREUR: 1.01, 95% CI, 0.99-1.04, P = 0.3). Nineteen of the 25 metabolites were glycerophospholipids and triacylglycerols (TAG). Eighteen associations exhibited significant heterogeneity between the two racial groups (PEUR-EA-Het < 0.005), which were more strongly associated in the EA population. This integrative study suggested a potential role of lipids, especially certain glycerophospholipids and TAGs, in the etiology of colorectal cancer. CONCLUSIONS: This study identified potential novel risk biomarkers for colorectal cancer by integrating genetics and circulating metabolomics data. IMPACT: The identified metabolites could be developed into new tools for risk assessment of colorectal cancer in both European and EA populations.


Assuntos
Neoplasias Colorretais , Estudos de Casos e Controles , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Glicerofosfolipídeos , Humanos , Lipídeos , Metabolômica/métodos
10.
J Natl Cancer Inst ; 114(4): 528-539, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35026030

RESUMO

BACKGROUND: The incidence of colorectal cancer (CRC) among individuals aged younger than 50 years has been increasing. As screening guidelines lower the recommended age of screening initiation, concerns including the burden on screening capacity and costs have been recognized, suggesting that an individualized approach may be warranted. We developed risk prediction models for early-onset CRC that incorporate an environmental risk score (ERS), including 16 lifestyle and environmental factors, and a polygenic risk score (PRS) of 141 variants. METHODS: Relying on risk score weights for ERS and PRS derived from studies of CRC at all ages, we evaluated risks for early-onset CRC in 3486 cases and 3890 controls aged younger than 50 years. Relative and absolute risks for early-onset CRC were assessed according to values of the ERS and PRS. The discriminatory performance of these scores was estimated using the covariate-adjusted area under the receiver operating characteristic curve. RESULTS: Increasing values of ERS and PRS were associated with increasing relative risks for early-onset CRC (odds ratio per SD of ERS = 1.14, 95% confidence interval [CI] = 1.08 to 1.20; odds ratio per SD of PRS = 1.59, 95% CI = 1.51 to 1.68), both contributing to case-control discrimination (area under the curve = 0.631, 95% CI = 0.615 to 0.647). Based on absolute risks, we can expect 26 excess cases per 10 000 men and 21 per 10 000 women among those scoring at the 90th percentile for both risk scores. CONCLUSIONS: Personal risk scores have the potential to identify individuals at differential relative and absolute risk for early-onset CRC. Improved discrimination may aid in targeted CRC screening of younger, high-risk individuals, potentially improving outcomes.


Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Idoso , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco
11.
Sci Rep ; 12(1): 127, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34996992

RESUMO

Identification of new genetic markers may improve the prediction of colorectal cancer prognosis. Our objective was to examine genome-wide associations of germline genetic variants with disease-specific survival in an analysis of 16,964 cases of colorectal cancer. We analyzed genotype and colorectal cancer-specific survival data from a consortium of 15 studies. Approximately 7.5 million SNPs were examined under the log-additive model using Cox proportional hazards models, adjusting for clinical factors and principal components. Additionally, we ran secondary analyses stratifying by tumor site and disease stage. We used a genome-wide p-value threshold of 5 × 10-8 to assess statistical significance. No variants were statistically significantly associated with disease-specific survival in the full case analysis or in the stage-stratified analyses. Three SNPs were statistically significantly associated with disease-specific survival for cases with tumors located in the distal colon (rs698022, HR = 1.48, CI 1.30-1.69, p = 8.47 × 10-9) and the proximal colon (rs189655236, HR = 2.14, 95% CI 1.65-2.77, p = 9.19 × 10-9 and rs144717887, HR = 2.01, 95% CI 1.57-2.58, p = 3.14 × 10-8), whereas no associations were detected for rectal tumors. Findings from this large genome-wide association study highlight the potential for anatomical-site-stratified genome-wide studies to identify germline genetic risk variants associated with colorectal cancer-specific survival. Larger sample sizes and further replication efforts are needed to more fully interpret these findings.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Loci Gênicos , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Bases de Dados Genéticas , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Medição de Risco , Fatores de Risco , Adulto Jovem
12.
Int J Cancer ; 150(9): 1447-1454, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34888857

RESUMO

Elevated blood levels of C-reactive protein (CRP) have been linked to colorectal cancer (CRC) survival. We evaluated genetic variants associated with CRP levels and their interactions with sex and lifestyle factors in association with CRC-specific mortality. Our study included 16 142 CRC cases from the International Survival Analysis in Colorectal Cancer Consortium. We identified 618 common single nucleotide polymorphisms (SNPs) associated with CRP levels from the NHGRI-EBI GWAS Catalog. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between SNPs and CRC-specific mortality adjusting for age, sex, genotyping platform/study and principal components. We investigated their interactions with sex and lifestyle factors using likelihood ratio tests. Of 5472 (33.9%) deaths accrued over up to 10 years of follow-up, 3547 (64.8%) were due to CRC. No variants were associated with CRC-specific mortality after multiple comparison correction. We observed strong evidence of interaction between variant rs1933736 at FRK gene and sex in relation to CRC-specific mortality (corrected Pinteraction  = .0004); women had higher CRC-specific mortality associated with the minor allele (HR = 1.11, 95% CI = 1.04-1.19) whereas an inverse association was observed for men (HR = 0.88, 95% CI = 0.82-0.94). There was no evidence of interactions between CRP-associated SNPs and alcohol, obesity or smoking. Our study observed a significant interaction between sex and a CRP-associated variant in relation to CRC-specific mortality. Future replication of this association and functional annotation of the variant are needed.


Assuntos
Proteína C-Reativa , Neoplasias Colorretais , Proteína C-Reativa/análise , Proteína C-Reativa/genética , Feminino , Humanos , Estilo de Vida , Masculino , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Análise de Sobrevida
13.
Patient Educ Couns ; 105(4): 987-995, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34400040

RESUMO

OBJECTIVE: A genomic test to predict personal risk of colorectal cancer (CRC) that targets screening and could be feasibly implemented in primary care. We explored informed decision-making and attitudes towards genomic testing in this setting. METHODS: A CRC genomic test was offered to 150 general practice patients with brief discussion of its implications. We measured informed choice about the test, consisting knowledge, attitudes and test uptake. Sixteen purposively-sampled participants were interviewed. RESULTS: Of 150, 142 (95%) completed the informed choice measure and of 27 invited, 16 (59%) completed an interview. 73% made an informed choice about the test. Interviews revealed that participants with inadequate knowledge on the informed choice scale still understood the gist of the test. While positive attitudes were most prevalent, some had concerns, and many were indifferent to the test. Positive attitudes included: that risk information could facilitate risk reduction; negative attitudes included: that risk results could cause worry and be used for insurance discrimination; indifferent attitudes included: that the test seemed benign and it was easy to do. CONCLUSIONS: Our study adds to the evidence that genomic tests for CRC risk do not pose significant concern to patients in community settings. PRACTICE IMPLICATIONS: As genomic tests become more prevalent, this study's findings can be used to facilitate informed decision-making and ensure equitable access.


Assuntos
Neoplasias Colorretais , Medicina Geral , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Detecção Precoce de Câncer/métodos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Programas de Rastreamento
14.
Fam Cancer ; 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34817745

RESUMO

Germline loss-of-function variants in AXIN2 are associated with oligodontia and ectodermal dysplasia. The association between colorectal cancer (CRC) and colonic polyposis is less clear despite this gene now being included in multi-gene panels for CRC. Study participants were people with genetically unexplained colonic polyposis recruited to the Genetics of Colonic Polyposis Study who had a rare germline AXIN2 gene variant identified from either clinical multi-gene panel testing (n=2) or from whole genome/exome sequencing (n=2). Variant segregation in relatives and characterisation of tumour tissue were performed where possible. Four different germline pathogenic variants in AXIN2 were identified in four families. Five of the seven carriers of the c.1049delC, p.Pro350Leufs*13 variant, two of the six carriers of the c.1994dupG, p.Asn666Glnfs*41 variant, all three carriers of c.1972delA, p.Ser658Alafs*31 variant and the single proband carrier of the c.2405G>C, p.Arg802Thr variant, which creates an alternate splice form resulting in a frameshift mutation (p.Glu763Ilefs*42), were affected by CRC and/or polyposis. Carriers had a mean age at diagnosis of CRC/polyposis of 52.5 ± 9.2 years. Colonic polyps were typically pan colonic with counts ranging from 5 to >100 (median 12.5) comprising predominantly adenomatous polyps but also serrated polyps. Two CRCs from carriers displayed evidence of a second hit via loss of heterozygosity. Oligodontia was observed in carriers from two families. Germline AXIN2 pathogenic variants from four families were associated with CRC and/or polyposis in multiple family members. These findings support the inclusion of AXIN2 in CRC and polyposis multigene panels for clinical testing.

15.
JNCI Cancer Spectr ; 5(4)2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34377935

RESUMO

Background: Smoking is associated with colorectal cancer (CRC) risk. Previous studies suggested this association may be restricted to certain molecular subtypes of CRC, but large-scale comprehensive analysis is lacking. Methods: A total of 9789 CRC cases and 11 231 controls of European ancestry from 11 observational studies were included. We harmonized smoking variables across studies and derived sex study-specific quartiles of pack-years of smoking for analysis. Four somatic colorectal tumor markers were assessed individually and in combination, including BRAF mutation, KRAS mutation, CpG island methylator phenotype (CIMP), and microsatellite instability (MSI) status. A multinomial logistic regression analysis was used to assess the association between smoking and risk of CRC subtypes by molecular characteristics, adjusting for age, sex, and study. All statistical tests were 2-sided and adjusted for Bonferroni correction. Results: Heavier smoking was associated with higher risk of CRC overall and stratified by individual markers (P trend < .001). The associations differed statistically significantly between all molecular subtypes, which was the most statistically significant for CIMP and BRAF. Compared with never-smokers, smokers in the fourth quartile of pack-years had a 90% higher risk of CIMP-positive CRC (odds ratio = 1.90, 95% confidence interval = 1.60 to 2.26) but only 35% higher risk for CIMP-negative CRC (odds ratio = 1.35, 95% confidence interval = 1.22 to 1.49; P difference = 2.1 x 10-6). The association was also stronger in tumors that were CIMP positive, MSI high, or KRAS wild type when combined (P difference < .001). Conclusion: Smoking was associated with differential risk of CRC subtypes defined by molecular characteristics. Heavier smokers had particularly higher risk of CRC subtypes that were CIMP positive and MSI high in combination, suggesting that smoking may be involved in the development of colorectal tumors via the serrated pathway.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Instabilidade de Microssatélites , Mutação , Fumar/efeitos adversos , Fatores Etários , Estudos de Casos e Controles , Ilhas de CpG/genética , Feminino , Genes ras/genética , Marcadores Genéticos/genética , Humanos , Modelos Logísticos , Masculino , Metilação , não Fumantes , Estudos Observacionais como Assunto , Fenótipo , Proteínas Proto-Oncogênicas B-raf/genética , Fatores Sexuais , Fumantes
16.
Cancers (Basel) ; 13(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34298744

RESUMO

MSH3 gene or protein deficiency or loss-of-function in colorectal cancer can cause a DNA mismatch repair defect known as "elevated microsatellite alterations at selected tetranucleotide repeats" (EMAST). A high percentage of MSI-H tumors exhibit EMAST, while MSI-L is also linked with EMAST. However, the distribution of CpG island methylator phenotype (CIMP) within the EMAST spectrum is not known. Five tetranucleotide repeat and five MSI markers were used to classify 100 sporadic colorectal tumours for EMAST, MSI-H and MSI-L according to the number of unstable markers detected. Promoter methylation was determined using methylation-specific PCR for MSH3, MCC, CDKN2A (p16) and five CIMP marker genes. EMAST was found in 55% of sporadic colorectal carcinomas. Carcinomas with only one positive marker (EMAST-1/5, 26%) were associated with advanced tumour stage, increased lymph node metastasis, MSI-L and lack of CIMP-H. EMAST-2/5 (16%) carcinomas displayed some methylation but MSI was rare. Carcinomas with ≥3 positive EMAST markers (13%) were more likely to have a proximal colon location and be MSI-H and CIMP-H. Our study suggests that EMAST/MSI-L is a valuable prognostic and predictive marker for colorectal carcinomas that do not display the high methylation phenotype CIMP-H.

17.
J Clin Med ; 10(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203177

RESUMO

BACKGROUND: Lynch syndrome is the most common genetic predisposition for hereditary cancer. Carriers of pathogenic changes in mismatch repair (MMR) genes have an increased risk of developing colorectal (CRC), endometrial, ovarian, urinary tract, prostate, and other cancers, depending on which gene is malfunctioning. In Lynch syndrome, differences in cancer incidence (penetrance) according to the gene involved have led to the stratification of cancer surveillance. By contrast, any differences in penetrance determined by the type of pathogenic variant remain unknown. OBJECTIVE: To determine cumulative incidences of cancer in carriers of truncating and missense or aberrant splicing pathogenic variants of the MLH1 and MSH2 genes. METHODS: Carriers of pathogenic variants of MLH1 (path_MLH1) and MSH2 (path_MSH2) genes filed in the Prospective Lynch Syndrome Database (PLSD) were categorized as truncating or missense/aberrant splicing according to the InSiGHT criteria for pathogenicity. RESULTS: Among 5199 carriers, 1045 had missense or aberrant splicing variants, and 3930 had truncating variants. Prospective observation years for the two groups were 8205 and 34,141 years, respectively, after which there were no significant differences in incidences for cancer overall or for colorectal cancer or endometrial cancers separately. CONCLUSION: Truncating and missense or aberrant splicing pathogenic variants were associated with similar average cumulative incidences of cancer in carriers of path MLH1 and path_MSH2.

18.
Cancers (Basel) ; 13(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070516

RESUMO

We investigated aberrant DNA methylation (DNAm) changes and the contribution of ageing-associated methylomic drift and age acceleration to early-onset colorectal cancer (EOCRC) carcinogenesis. Genome-wide DNAm profiling using the Infinium HM450K on 97 EOCRC tumour and 54 normal colonic mucosa samples was compared with: (1) intermediate-onset CRC (IOCRC; diagnosed between 50-70 years; 343 tumour and 35 normal); and (2) late-onset CRC (LOCRC; >70 years; 318 tumour and 40 normal). CpGs associated with age-related methylation drift were identified using a public dataset of 231 normal mucosa samples from people without CRC. DNAm-age was estimated using epiTOC2. Common to all three age-of-onset groups, 88,385 (20% of all CpGs) CpGs were differentially methylated between tumour and normal mucosa. We identified 234 differentially methylated genes that were unique to the EOCRC group; 13 of these DMRs/genes were replicated in EOCRC compared with LOCRCs from TCGA. In normal mucosa from people without CRC, we identified 28,154 CpGs that undergo ageing-related DNAm drift, and of those, 65% were aberrantly methylated in EOCRC tumours. Based on the mitotic-based DNAm clock epiTOC2, we identified age acceleration in normal mucosa of people with EOCRC compared with normal mucosa from the IOCRC, LOCRC groups (p = 3.7 × 10-16) and young people without CRC (p = 5.8 × 10-6). EOCRC acquires unique DNAm alterations at 234 loci. CpGs associated with ageing-associated drift were widely affected in EOCRC without needing the decades-long accrual of DNAm drift as commonly seen in intermediate- and late-onset CRCs. Accelerated ageing in normal mucosa from people with EOCRC potentially underlies the earlier age of diagnosis in CRC carcinogenesis.

19.
JNCI Cancer Spectr ; 5(3)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34041438

RESUMO

Background: Incidence of early-onset (younger than 50 years of age) colorectal cancer (CRC) is increasing in many countries. Thus, elucidating the role of traditional CRC risk factors in early-onset CRC is a high priority. We sought to determine whether risk factors associated with late-onset CRC were also linked to early-onset CRC and whether association patterns differed by anatomic subsite. Methods: Using data pooled from 13 population-based studies, we studied 3767 CRC cases and 4049 controls aged younger than 50 years and 23 437 CRC cases and 35 311 controls aged 50 years and older. Using multivariable and multinomial logistic regression, we estimated odds ratios (ORs) and 95% confidence intervals (CIs) to assess the association between risk factors and early-onset CRC and by anatomic subsite. Results: Early-onset CRC was associated with not regularly using nonsteroidal anti-inflammatory drugs (OR = 1.43, 95% CI = 1.21 to 1.68), greater red meat intake (OR = 1.10, 95% CI = 1.04 to 1.16), lower educational attainment (OR = 1.10, 95% CI = 1.04 to 1.16), alcohol abstinence (OR = 1.23, 95% CI = 1.08 to 1.39), and heavier alcohol use (OR = 1.25, 95% CI = 1.04 to 1.50). No factors exhibited a greater excess in early-onset compared with late-onset CRC. Evaluating risks by anatomic subsite, we found that lower total fiber intake was linked more strongly to rectal (OR = 1.30, 95% CI = 1.14 to 1.48) than colon cancer (OR = 1.14, 95% CI = 1.02 to 1.27; P = .04). Conclusion: In this large study, we identified several nongenetic risk factors associated with early-onset CRC, providing a basis for targeted identification of those most at risk, which is imperative in mitigating the rising burden of this disease.


Assuntos
Neoplasias do Colo/etiologia , Neoplasias Retais/etiologia , Adulto , Idade de Início , Idoso , Alcoolismo/complicações , Alcoolismo/epidemiologia , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Estudos de Casos e Controles , Bovinos , Neoplasias do Colo/epidemiologia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia , Intervalos de Confiança , Fibras na Dieta/administração & dosagem , Escolaridade , Humanos , Incidência , Modelos Logísticos , Carne , Pessoa de Meia-Idade , Razão de Chances , Neoplasias Retais/epidemiologia , Fatores de Risco
20.
Cancer Epidemiol Biomarkers Prev ; 30(7): 1349-1358, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33972368

RESUMO

BACKGROUND: A positive association between circulating C-reactive protein (CRP) and colorectal cancer survival was reported in observational studies, which are susceptible to unmeasured confounding and reverse causality. We used a Mendelian randomization approach to evaluate the association between genetically predicted CRP concentrations and colorectal cancer-specific survival. METHODS: We used individual-level data for 16,918 eligible colorectal cancer cases of European ancestry from 15 studies within the International Survival Analysis of Colorectal Cancer Consortium. We calculated a genetic-risk score based on 52 CRP-associated genetic variants identified from genome-wide association studies. Because of the non-collapsibility of hazard ratios from Cox proportional hazards models, we used the additive hazards model to calculate hazard differences (HD) and 95% confidence intervals (CI) for the association between genetically predicted CRP concentrations and colorectal cancer-specific survival, overall and by stage at diagnosis and tumor location. Analyses were adjusted for age at diagnosis, sex, body mass index, genotyping platform, study, and principal components. RESULTS: Of the 5,395 (32%) deaths accrued over up to 10 years of follow-up, 3,808 (23%) were due to colorectal cancer. Genetically predicted CRP concentration was not associated with colorectal cancer-specific survival (HD, -1.15; 95% CI, -2.76 to 0.47 per 100,000 person-years; P = 0.16). Similarly, no associations were observed in subgroup analyses by stage at diagnosis or tumor location. CONCLUSIONS: Despite adequate power to detect moderate associations, our results did not support a causal effect of circulating CRP concentrations on colorectal cancer-specific survival. IMPACT: Future research evaluating genetically determined levels of other circulating inflammatory biomarkers (i.e., IL6) with colorectal cancer survival outcomes is needed.


Assuntos
Proteína C-Reativa/análise , Neoplasias Colorretais/mortalidade , Idoso , Estudos de Casos e Controles , Neoplasias Colorretais/sangue , Neoplasias Colorretais/genética , Feminino , Seguimentos , Variação Genética , Humanos , Masculino , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Fatores de Risco
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