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1.
Life (Basel) ; 11(3)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809741

RESUMO

Changes in the gut microbiome have already been associated with postoperative complications in major abdominal surgery. However, it is still unclear whether these changes are transient or a long-lasting effect. Therefore, the aim of this prospective clinical pilot study was to examine long-term changes in the gut microbiota and to correlate these changes with the clinical course of the patient. Methods: In total, stool samples of 62 newly diagnosed colorectal cancer patients undergoing primary tumor resection were analyzed by 16S-rDNA next-generation sequencing. Stool samples were collected preoperatively in order to determine the gut microbiome at baseline as well as at 6, 12, and 24 months thereafter to observe longitudinal changes. Postoperatively, the study patients were separated into two groups-patients who suffered from postoperative complications (n = 30) and those without complication (n = 32). Patients with postoperative complications showed a significantly stronger reduction in the alpha diversity starting 6 months after operation, which does not resolve, even after 24 months. The structure of the microbiome was also significantly altered from baseline at six-month follow-up in patients with complications (p = 0.006). This was associated with a long-lasting decrease of a large number of species in the gut microbiota indicating an impact in the commensal microbiota and a long-lasting increase of Fusobacterium ulcerans. The microbial composition of the gut microbiome shows significant changes in patients with postoperative complications up to 24 months after surgery.

2.
Cancer Epidemiol Biomarkers Prev ; 30(5): 953-964, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33653810

RESUMO

BACKGROUND: Observational evidence has shown that smoking is a risk factor for breast and colorectal cancer. We used Mendelian randomization (MR) to examine causal associations between smoking and risks of breast and colorectal cancer. METHODS: Genome-Wide Association Study summary data were used to identify genetic variants associated with lifetime amount of smoking (n = 126 variants) and ever having smoked regularly (n = 112 variants). Using two-sample MR, we examined these variants in relation to incident breast (122,977 cases/105,974 controls) and colorectal cancer (52,775 cases/45,940 controls). RESULTS: In inverse-variance weighted models, a genetic predisposition to higher lifetime amount of smoking was positively associated with breast cancer risk [OR per 1-SD increment: 1.13; 95% confidence interval (CI): 1.00-1.26; P = 0.04]; although heterogeneity was observed. Similar associations were found for estrogen receptor-positive and estrogen receptor-negative tumors. Higher lifetime amount of smoking was positively associated with colorectal cancer (OR per 1-SD increment, 1.21; 95% CI, 1.04-1.40; P = 0.01), colon cancer (OR, 1.31; 95% CI, 1.11-1.55; P < 0.01), and rectal cancer (OR, 1.36; 95% CI, 1.07-1.73; P = 0.01). Ever having smoked regularly was not associated with risks of breast (OR, 1.01; 95% CI, 0.90-1.14; P = 0.85) or colorectal cancer (OR, 0.97; 95% CI, 0.86-1.10; P = 0.68). CONCLUSIONS: These findings are consistent with prior observational evidence and support a causal role of higher lifetime smoking amount in the development of breast and colorectal cancer. IMPACT: The results from this comprehensive MR analysis indicate that lifetime smoking is a causal risk factor for these common malignancies.

3.
Am J Clin Nutr ; 113(6): 1490-1502, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33740060

RESUMO

BACKGROUND: The literature on associations of circulating concentrations of minerals and vitamins with risk of colorectal cancer is limited and inconsistent. Evidence from randomized controlled trials (RCTs) to support the efficacy of dietary modification or nutrient supplementation for colorectal cancer prevention is also limited. OBJECTIVES: To complement observational and RCT findings, we investigated associations of genetically predicted concentrations of 11 micronutrients (ß-carotene, calcium, copper, folate, iron, magnesium, phosphorus, selenium, vitamin B-6, vitamin B-12, and zinc) with colorectal cancer risk using Mendelian randomization (MR). METHODS: Two-sample MR was conducted using 58,221 individuals with colorectal cancer and 67,694 controls from the Genetics and Epidemiology of Colorectal Cancer Consortium, Colorectal Cancer Transdisciplinary Study, and Colon Cancer Family Registry. Inverse variance-weighted MR analyses were performed with sensitivity analyses to assess the impact of potential violations of MR assumptions. RESULTS: Nominally significant associations were noted for genetically predicted iron concentration and higher risk of colon cancer [ORs per SD (ORSD): 1.08; 95% CI: 1.00, 1.17; P value = 0.05] and similarly for proximal colon cancer, and for vitamin B-12 concentration and higher risk of colorectal cancer (ORSD: 1.12; 95% CI: 1.03, 1.21; P value = 0.01) and similarly for colon cancer. A nominally significant association was also noted for genetically predicted selenium concentration and lower risk of colon cancer (ORSD: 0.98; 95% CI: 0.96, 1.00; P value = 0.05) and similarly for distal colon cancer. These associations were robust to sensitivity analyses. Nominally significant inverse associations were observed for zinc and risk of colorectal and distal colon cancers, but sensitivity analyses could not be performed. None of these findings survived correction for multiple testing. Genetically predicted concentrations of ß-carotene, calcium, copper, folate, magnesium, phosphorus, and vitamin B-6 were not associated with disease risk. CONCLUSIONS: These results suggest possible causal associations of circulating iron and vitamin B-12 (positively) and selenium (inversely) with risk of colon cancer.


Assuntos
Neoplasias Colorretais/genética , Grupo com Ancestrais do Continente Europeu , Predisposição Genética para Doença , Análise da Randomização Mendeliana , Micronutrientes/administração & dosagem , Estudos de Casos e Controles , Suplementos Nutricionais , Humanos , Fatores de Risco , Selênio/sangue , Vitamina B 12/sangue
5.
BMJ Open ; 11(2): e043584, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33579769

RESUMO

OBJECTIVE: We sought to determine the extent of SARS-CoV-2 seroprevalence and the factors associated with seroprevalence across a diverse cohort of healthcare workers. DESIGN: Observational cohort study of healthcare workers, including SARS-CoV-2 serology testing and participant questionnaires. SETTINGS: A multisite healthcare delivery system located in Los Angeles County. PARTICIPANTS: A diverse and unselected population of adults (n=6062) employed in a multisite healthcare delivery system located in Los Angeles County, including individuals with direct patient contact and others with non-patient-oriented work functions. MAIN OUTCOMES: Using Bayesian and multivariate analyses, we estimated seroprevalence and factors associated with seropositivity and antibody levels, including pre-existing demographic and clinical characteristics; potential COVID-19 illness-related exposures; and symptoms consistent with COVID-19 infection. RESULTS: We observed a seroprevalence rate of 4.1%, with anosmia as the most prominently associated self-reported symptom (OR 11.04, p<0.001) in addition to fever (OR 2.02, p=0.002) and myalgias (OR 1.65, p=0.035). After adjusting for potential confounders, seroprevalence was also associated with Hispanic ethnicity (OR 1.98, p=0.001) and African-American race (OR 2.02, p=0.027) as well as contact with a COVID-19-diagnosed individual in the household (OR 5.73, p<0.001) or clinical work setting (OR 1.76, p=0.002). Importantly, African-American race and Hispanic ethnicity were associated with antibody positivity even after adjusting for personal COVID-19 diagnosis status, suggesting the contribution of unmeasured structural or societal factors. CONCLUSION AND RELEVANCE: The demographic factors associated with SARS-CoV-2 seroprevalence among our healthcare workers underscore the importance of exposure sources beyond the workplace. The size and diversity of our study population, combined with robust survey and modelling techniques, provide a vibrant picture of the demographic factors, exposures and symptoms that can identify individuals with susceptibility as well as potential to mount an immune response to COVID-19.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/diagnóstico , Pessoal de Saúde , Estudos Soroepidemiológicos , Adulto , Teorema de Bayes , COVID-19/imunologia , Teste Sorológico para COVID-19 , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Los Angeles/epidemiologia , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/imunologia
6.
Cancer Epidemiol Biomarkers Prev ; 30(5): 895-903, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33627384

RESUMO

BACKGROUND: Inherited susceptibility is an important contributor to colorectal cancer risk, and rare variants in key genes or pathways could account in part for the missing proportion of colorectal cancer heritability. METHODS: We conducted an exome-wide association study including 2,327 cases and 2,966 controls of European ancestry from three large epidemiologic studies. Single variant associations were tested using logistic regression models, adjusting for appropriate study-specific covariates. In addition, we examined the aggregate effects of rare coding variation at the gene and pathway levels using Bayesian model uncertainty techniques. RESULTS: In an exome-wide gene-level analysis, we identified ST6GALNAC2 as the top associated gene based on the Bayesian risk index (BRI) method [summary Bayes factor (BF)BRI = 2604.23]. A rare coding variant in this gene, rs139401613, was the top associated variant (P = 1.01 × 10-6) in an exome-wide single variant analysis. Pathway-level association analyses based on the integrative BRI (iBRI) method found extreme evidence of association with the DNA repair pathway (BFiBRI = 17852.4), specifically with the nonhomologous end joining (BFiBRI = 437.95) and nucleotide excision repair (BFiBRI = 36.96) subpathways. The iBRI method also identified RPA2, PRKDC, ERCC5, and ERCC8 as the top associated DNA repair genes (summary BFiBRI ≥ 10), with rs28988897, rs8178232, rs141369732, and rs201642761 being the most likely associated variants in these genes, respectively. CONCLUSIONS: We identified novel variants and genes associated with colorectal cancer risk and provided additional evidence for a role of DNA repair in colorectal cancer tumorigenesis. IMPACT: This study provides new insights into the genetic predisposition to colorectal cancer, which has potential for translation into improved risk prediction.

7.
Am J Epidemiol ; 190(2): 230-238, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33524116

RESUMO

People with Lynch syndrome (LS), who carry a pathogenic mutation in a DNA mismatch repair gene, have increased risks of colorectal cancer (CRC) and endometrial cancer (EC). A high reported variability in cancer risk suggests the existence of factors that modify cancer risk for persons with LS. We aimed to investigate the associations between height and CRC and EC risk for persons with LS using data from 2 large studies. Information on 1,115 men and 1,553 women with LS from the Colon Cancer Family Registry (1998-2007) and the GEOLynch Cohort Study (2006-2017) was harmonized. We used weighted Cox proportional hazards regression models with age on the time axis to estimate adjusted hazard ratios and 95% confidence intervals for each 5-cm increment in self-reported height. CRC was diagnosed in 947 persons during 65,369 person-years of observation, and 171 women were diagnosed with EC during 39,227 person-years. Height was not associated with CRC for either men (per 5-cm increment, hazard ratio (HR) = 1.00, 95% confidence interval (CI): 0.91, 1.11) or women (per 5-cm increment, HR = 1.01, 95% CI: 0.92, 1.11), nor was height associated with EC (per 5-cm increment, HR = 1.08, 95% CI: 0.94, 1.24). Hence, we observed no evidence for an association of height with either CRC or EC among persons with LS.


Assuntos
Estatura , Neoplasias Colorretais/epidemiologia , Neoplasias do Endométrio/epidemiologia , Adulto , Fatores Etários , Neoplasias Colorretais/genética , Neoplasias Colorretais Hereditárias sem Polipose/epidemiologia , Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo de Erro de Pareamento de DNA , Neoplasias do Endométrio/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco , Fatores Sexuais
8.
J Natl Cancer Inst ; 113(7): 833-840, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33528005

RESUMO

BACKGROUND: Aspirin use reduces colorectal cancer (CRC) incidence, but there is limited evidence regarding associations of aspirin and non-aspirin non-steroidal anti-inflammatory drugs (NSAIDs) with CRC-specific survival. METHODS: This prospective analysis includes women and men from the Cancer Prevention Study-II Nutrition Cohort who were cancer free at baseline (1992 or 1993) and diagnosed with CRC during incidence follow-up through 2015. Detailed information on aspirin and non-aspirin NSAID use was self-reported on questionnaires at baseline, in 1997, and every 2 years thereafter. Pre- and postdiagnosis data were available for 2686 and 1931 participants without distant metastases, respectively, among whom 512 and 251 died from CRC during mortality follow-up through 2016. Secondary analyses examined associations between prediagnosis aspirin use and stage at diagnosis (distant metastatic vs localized or regional). All statistical tests were 2-sided. RESULTS: Long-term regular use of aspirin (>15 times per month) before diagnosis was associated with lower CRC-specific mortality (multivariable-adjusted hazard ratio [HR] = 0.69, 95% confidence interval [CI] = 0.52 to 0.92). Postdiagnosis regular aspirin use was not statistically significantly associated with risk of CRC-specific mortality overall (HR = 0.82, 95% CI = 0.62 to 1.09), although participants who began regular aspirin use only after their diagnosis were at lower risk than participants who did not use aspirin at both the pre- and postdiagnosis periods (HR = 0.60, 95% CI = 0.36 to 0.98). Long-term aspirin use before diagnosis was also associated with lower odds of diagnosis with distant metastases (multivariable-adjusted odds ratio = 0.73, 95% CI = 0.53 to 0.99). CONCLUSIONS: Our results suggest that long-term aspirin use before a diagnosis of nonmetastatic colorectal cancer may be associated with lower CRC-specific mortality after diagnosis, consistent with possible inhibition of micrometastases before diagnosis.

9.
Gut ; 70(7): 1325-1334, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33632709

RESUMO

OBJECTIVE: An understanding of the etiologic heterogeneity of colorectal cancer (CRC) is critical for improving precision prevention, including individualized screening recommendations and the discovery of novel drug targets and repurposable drug candidates for chemoprevention. Known differences in molecular characteristics and environmental risk factors among tumors arising in different locations of the colorectum suggest partly distinct mechanisms of carcinogenesis. The extent to which the contribution of inherited genetic risk factors for CRC differs by anatomical subsite of the primary tumor has not been examined. DESIGN: To identify new anatomical subsite-specific risk loci, we performed genome-wide association study (GWAS) meta-analyses including data of 48 214 CRC cases and 64 159 controls of European ancestry. We characterised effect heterogeneity at CRC risk loci using multinomial modelling. RESULTS: We identified 13 loci that reached genome-wide significance (p<5×10-8) and that were not reported by previous GWASs for overall CRC risk. Multiple lines of evidence support candidate genes at several of these loci. We detected substantial heterogeneity between anatomical subsites. Just over half (61) of 109 known and new risk variants showed no evidence for heterogeneity. In contrast, 22 variants showed association with distal CRC (including rectal cancer), but no evidence for association or an attenuated association with proximal CRC. For two loci, there was strong evidence for effects confined to proximal colon cancer. CONCLUSION: Genetic architectures of proximal and distal CRC are partly distinct. Studies of risk factors and mechanisms of carcinogenesis, and precision prevention strategies should take into consideration the anatomical subsite of the tumour.

10.
Br J Cancer ; 124(2): 315-332, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32901135

RESUMO

There are well-established disparities in cancer incidence and outcomes by race/ethnicity that result from the interplay between structural, socioeconomic, socio-environmental, behavioural and biological factors. However, large research studies designed to investigate factors contributing to cancer aetiology and progression have mainly focused on populations of European origin. The limitations in clinicopathological and genetic data, as well as the reduced availability of biospecimens from diverse populations, contribute to the knowledge gap and have the potential to widen cancer health disparities. In this review, we summarise reported disparities and associated factors in the United States of America (USA) for the most common cancers (breast, prostate, lung and colon), and for a subset of other cancers that highlight the complexity of disparities (gastric, liver, pancreas and leukaemia). We focus on populations commonly identified and referred to as racial/ethnic minorities in the USA-African Americans/Blacks, American Indians and Alaska Natives, Asians, Native Hawaiians/other Pacific Islanders and Hispanics/Latinos. We conclude that even though substantial progress has been made in understanding the factors underlying cancer health disparities, marked inequities persist. Additional efforts are needed to include participants from diverse populations in the research of cancer aetiology, biology and treatment. Furthermore, to eliminate cancer health disparities, it will be necessary to facilitate access to, and utilisation of, health services to all individuals, and to address structural inequities, including racism, that disproportionally affect racial/ethnic minorities in the USA.


Assuntos
Disparidades nos Níveis de Saúde , Grupos Minoritários/estatística & dados numéricos , Neoplasias/etnologia , Grupos Étnicos/estatística & dados numéricos , Feminino , Humanos , Masculino , Estados Unidos/etnologia
11.
J Natl Cancer Inst ; 113(1): 38-47, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-32324875

RESUMO

BACKGROUND: Body mass index (BMI) is a complex phenotype that may interact with genetic variants to influence colorectal cancer risk. METHODS: We tested multiplicative statistical interactions between BMI (per 5 kg/m2) and approximately 2.7 million single nucleotide polymorphisms with colorectal cancer risk among 14 059 colorectal cancer case (53.2% women) and 14 416 control (53.8% women) participants. All analyses were stratified by sex a priori. Statistical methods included 2-step (ie, Cocktail method) and single-step (ie, case-control logistic regression and a joint 2-degree of freedom test) procedures. All statistical tests were two-sided. RESULTS: Each 5 kg/m2 increase in BMI was associated with higher risks of colorectal cancer, less so for women (odds ratio [OR] = 1.14, 95% confidence intervals [CI] = 1.11 to 1.18; P = 9.75 × 10-17) than for men (OR = 1.26, 95% CI = 1.20 to 1.32; P = 2.13 × 10-24). The 2-step Cocktail method identified an interaction for women, but not men, between BMI and a SMAD7 intronic variant at 18q21.1 (rs4939827; Pobserved = .0009; Pthreshold = .005). A joint 2-degree of freedom test was consistent with this finding for women (joint P = 2.43 × 10-10). Each 5 kg/m2 increase in BMI was more strongly associated with colorectal cancer risk for women with the rs4939827-CC genotype (OR = 1.24, 95% CI = 1.16 to 1.32; P = 2.60 × 10-10) than for women with the CT (OR = 1.14, 95% CI = 1.09 to 1.19; P = 1.04 × 10-8) or TT (OR = 1.07, 95% CI = 1.01 to 1.14; P = .02) genotypes. CONCLUSION: These results provide novel insights on a potential mechanism through which a SMAD7 variant, previously identified as a susceptibility locus for colorectal cancer, and BMI may influence colorectal cancer risk for women.


Assuntos
Índice de Massa Corporal , Neoplasias Colorretais/genética , Predisposição Genética para Doença , Proteína Smad7/genética , Idoso , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/patologia , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Medição de Risco , Fatores de Risco
12.
Cancer Epidemiol Biomarkers Prev ; 30(3): 564-575, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33318029

RESUMO

BACKGROUND: Evidence for aspirin's chemopreventative properties on colorectal cancer (CRC) is substantial, but its mechanism of action is not well-understood. We combined a proteomic approach with Mendelian randomization (MR) to identify possible new aspirin targets that decrease CRC risk. METHODS: Human colorectal adenoma cells (RG/C2) were treated with aspirin (24 hours) and a stable isotope labeling with amino acids in cell culture (SILAC) based proteomics approach identified altered protein expression. Protein quantitative trait loci (pQTLs) from INTERVAL (N = 3,301) and expression QTLs (eQTLs) from the eQTLGen Consortium (N = 31,684) were used as genetic proxies for protein and mRNA expression levels. Two-sample MR of mRNA/protein expression on CRC risk was performed using eQTL/pQTL data combined with CRC genetic summary data from the Colon Cancer Family Registry (CCFR), Colorectal Transdisciplinary (CORECT), Genetics and Epidemiology of Colorectal Cancer (GECCO) consortia and UK Biobank (55,168 cases and 65,160 controls). RESULTS: Altered expression was detected for 125/5886 proteins. Of these, aspirin decreased MCM6, RRM2, and ARFIP2 expression, and MR analysis showed that a standard deviation increase in mRNA/protein expression was associated with increased CRC risk (OR: 1.08, 95% CI, 1.03-1.13; OR: 3.33, 95% CI, 2.46-4.50; and OR: 1.15, 95% CI, 1.02-1.29, respectively). CONCLUSIONS: MCM6 and RRM2 are involved in DNA repair whereby reduced expression may lead to increased DNA aberrations and ultimately cancer cell death, whereas ARFIP2 is involved in actin cytoskeletal regulation, indicating a possible role in aspirin's reduction of metastasis. IMPACT: Our approach has shown how laboratory experiments and population-based approaches can combine to identify aspirin-targeted proteins possibly affecting CRC risk.

13.
BMC Med ; 18(1): 396, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33327948

RESUMO

BACKGROUND: Higher adiposity increases the risk of colorectal cancer (CRC), but whether this relationship varies by anatomical sub-site or by sex is unclear. Further, the metabolic alterations mediating the effects of adiposity on CRC are not fully understood. METHODS: We examined sex- and site-specific associations of adiposity with CRC risk and whether adiposity-associated metabolites explain the associations of adiposity with CRC. Genetic variants from genome-wide association studies of body mass index (BMI) and waist-to-hip ratio (WHR, unadjusted for BMI; N = 806,810), and 123 metabolites from targeted nuclear magnetic resonance metabolomics (N = 24,925), were used as instruments. Sex-combined and sex-specific Mendelian randomization (MR) was conducted for BMI and WHR with CRC risk (58,221 cases and 67,694 controls in the Genetics and Epidemiology of Colorectal Cancer Consortium, Colorectal Cancer Transdisciplinary Study, and Colon Cancer Family Registry). Sex-combined MR was conducted for BMI and WHR with metabolites, for metabolites with CRC, and for BMI and WHR with CRC adjusted for metabolite classes in multivariable models. RESULTS: In sex-specific MR analyses, higher BMI (per 4.2 kg/m2) was associated with 1.23 (95% confidence interval (CI) = 1.08, 1.38) times higher CRC odds among men (inverse-variance-weighted (IVW) model); among women, higher BMI (per 5.2 kg/m2) was associated with 1.09 (95% CI = 0.97, 1.22) times higher CRC odds. WHR (per 0.07 higher) was more strongly associated with CRC risk among women (IVW OR = 1.25, 95% CI = 1.08, 1.43) than men (IVW OR = 1.05, 95% CI = 0.81, 1.36). BMI or WHR was associated with 104/123 metabolites at false discovery rate-corrected P ≤ 0.05; several metabolites were associated with CRC, but not in directions that were consistent with the mediation of positive adiposity-CRC relations. In multivariable MR analyses, associations of BMI and WHR with CRC were not attenuated following adjustment for representative metabolite classes, e.g., the univariable IVW OR for BMI with CRC was 1.12 (95% CI = 1.00, 1.26), and this became 1.11 (95% CI = 0.99, 1.26) when adjusting for cholesterol in low-density lipoprotein particles. CONCLUSIONS: Our results suggest that higher BMI more greatly raises CRC risk among men, whereas higher WHR more greatly raises CRC risk among women. Adiposity was associated with numerous metabolic alterations, but none of these explained associations between adiposity and CRC. More detailed metabolomic measures are likely needed to clarify the mechanistic pathways.


Assuntos
Adiposidade/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Metaboloma/genética , Adulto , Índice de Massa Corporal , Estudos de Casos e Controles , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia , Europa (Continente)/epidemiologia , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/estatística & dados numéricos , Humanos , Masculino , Análise da Randomização Mendeliana , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/epidemiologia , Obesidade/genética , Obesidade/metabolismo , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Fatores Sexuais , Relação Cintura-Quadril
14.
Cancer Epidemiol Biomarkers Prev ; 29(12): 2719-2728, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33008876

RESUMO

BACKGROUND: High numbers of lymphocytes in tumor tissue, including T regulatory cells (Treg), have been associated with better colorectal cancer survival. Tregs, a subset of CD4+ T lymphocytes, are mediators of immunosuppression in cancer, and therefore variants in genes related to Treg differentiation and function could be associated with colorectal cancer prognosis. METHODS: In a prospective German cohort of 3,593 colorectal cancer patients, we assessed the association of 771 single-nucleotide polymorphisms (SNP) in 58 Treg-related genes with overall and colorectal cancer-specific survival using Cox regression models. Effect modification by microsatellite instability (MSI) status was also investigated because tumors with MSI show greater lymphocytic infiltration and have been associated with better prognosis. Replication of significant results was attempted in 2,047 colorectal cancer patients of the International Survival Analysis in Colorectal Cancer Consortium (ISACC). RESULTS: A significant association of the TGFBR3 SNP rs7524066 with more favorable colorectal cancer-specific survival [hazard ratio (HR) per minor allele: 0.83; 95% confidence interval (CI), 0.74-0.94; P value: 0.0033] was replicated in ISACC (HR: 0.82; 95% CI, 0.68-0.98; P value: 0.03). Suggestive evidence for association was found with two IL7 SNPs, rs16906568 and rs7845577. Thirteen SNPs with differential associations with overall survival according to MSI in the discovery analysis were not confirmed. CONCLUSIONS: Common genetic variation in the Treg pathway implicating genes such as TGFBR3 and IL7 was shown to be associated with prognosis of colorectal cancer patients. IMPACT: The implicated genes warrant further investigation.

15.
JNCI Cancer Spectr ; 4(5): pkaa042, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32923935

RESUMO

Background: Postmenopausal hormone therapy (HT) is associated with a decreased colorectal cancer (CRC) risk. As CRC is a heterogeneous disease, we evaluated whether the association of HT and CRC differs across etiologically relevant, molecularly defined tumor subtypes and tumor location. Methods: We pooled data on tumor subtypes (microsatellite instability status, CpG island methylator phenotype status, BRAF and KRAS mutations, pathway: adenoma-carcinoma, alternate, serrated), tumor location (proximal colon, distal colon, rectum), and HT use among 8220 postmenopausal women (3898 CRC cases and 4322 controls) from 8 observational studies. We used multinomial logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CIs) for the association of ever vs never HT use with each tumor subtype compared with controls. Models were adjusted for study, age, body mass index, smoking status, and CRC family history. All statistical tests were 2-sided. Results: Among postmenopausal women, ever HT use was associated with a 38% reduction in overall CRC risk (OR =0.62, 95% CI = 0.56 to 0.69). This association was similar according to microsatellite instability, CpG island methylator phenotype and BRAF or KRAS status. However, the association was attenuated for tumors arising through the serrated pathway (OR = 0.81, 95% CI = 0.66 to 1.01) compared with the adenoma-carcinoma pathway (OR = 0.63, 95% CI = 0.55 to 0.73; P het =.04) and alternate pathway (OR = 0.61, 95% CI = 0.51 to 0.72). Additionally, proximal colon tumors had a weaker association (OR = 0.71, 95% CI = 0.62 to 0.80) compared with rectal (OR = 0.54, 95% CI = 0.46 to 0.63) and distal colon (OR = 0.57, 95% CI = 0.49 to 0.66; P het =.01) tumors. Conclusions: We observed a strong inverse association between HT use and overall CRC risk, which may predominantly reflect a benefit of HT use for tumors arising through the adenoma-carcinoma and alternate pathways as well as distal colon and rectal tumors.

16.
Cancer Res ; 80(20): 4578-4590, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32816852

RESUMO

Protective associations of fruits, vegetables, and fiber intake with colorectal cancer risk have been shown in many, but not all epidemiologic studies. One possible reason for study heterogeneity is that dietary factors may have distinct effects by colorectal cancer molecular subtypes. Here, we investigate the association of fruit, vegetables, and fiber intake with four well-established colorectal cancer molecular subtypes separately and in combination. Nine observational studies including 9,592 cases with molecular subtypes for microsatellite instability (MSI), CpG island methylator phenotype (CIMP), and somatic mutations in BRAF and KRAS genes, and 7,869 controls were analyzed. Both case-only logistic regression analyses and polytomous logistic regression analyses (with one control set and multiple case groups) were used. Higher fruit intake was associated with a trend toward decreased risk of BRAF-mutated tumors [OR 4th vs. 1st quartile = 0.82 (95% confidence interval, 0.65-1.04)] but not BRAF-wildtype tumors [1.09 (0.97-1.22); P difference as shown in case-only analysis = 0.02]. This difference was observed in case-control studies and not in cohort studies. Compared with controls, higher fiber intake showed negative association with colorectal cancer risk for cases with microsatellite stable/MSI-low, CIMP-negative, BRAF-wildtype, and KRAS-wildtype tumors (P trend range from 0.03 to 3.4e-03), which is consistent with the traditional adenoma-colorectal cancer pathway. These negative associations were stronger compared with MSI-high, CIMP-positive, BRAF-mutated, or KRAS-mutated tumors, but the differences were not statistically significant. These inverse associations for fruit and fiber intake may explain, in part, inconsistent findings between fruit or fiber intake and colorectal cancer risk that have previously been reported. SIGNIFICANCE: These analyses by colorectal cancer molecular subtypes potentially explain the inconsistent findings between dietary fruit or fiber intake and overall colorectal cancer risk that have previously been reported.


Assuntos
Neoplasias Colorretais/etiologia , Neoplasias Colorretais/prevenção & controle , Fibras na Dieta/farmacologia , Frutas , Verduras , Estudos de Casos e Controles , Neoplasias Colorretais/patologia , Ilhas de CpG , Metilação de DNA , Feminino , Humanos , Masculino , Instabilidade de Microssatélites , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Fatores de Risco
17.
Am J Epidemiol ; 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32803246

RESUMO

Persons with Lynch syndrome (LS - carrying a pathogenic mutation in a DNA mismatch repair gene) have an increased colorectal cancer (CRC) and endometrial cancer (EC) risk. A high reported variability in cancer risk suggests the existence of factors that modify cancer risk for LS. We aimed to investigate the association between height and CRC and EC for persons with LS using two large studies. Information of 1,213 men and 1,636 women with LS from the Colon Cancer Family Registry (1998-2007) and the GEOLynch cohort study (2006-2017) was harmonized. We used weighted Cox proportional hazard regression models with age on the time-axis to estimate adjusted hazard ratios (HR) and 95% confidence intervals (CI) for each 5 cm increment in self-reported height. CRC was diagnosed in 947 persons during 65,369 person-years of observation and 171 women were diagnosed with EC during 39,227 person-years of observation. Height was not associated with CRC for men (HR 1.00 per 5 cm, 95%CI: 0.91, 1.11) or women (HR 1.01 per 5 cm, 95%CI: 0.92, 1.11). Nor was height associated with EC (HR 1.08 per 5 cm, 95%CI: 0.94, 1.24). Hence, we observed no evidence for an association of height with either CRC or EC for persons with LS.

18.
Am J Hum Genet ; 107(3): 432-444, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32758450

RESUMO

Accurate colorectal cancer (CRC) risk prediction models are critical for identifying individuals at low and high risk of developing CRC, as they can then be offered targeted screening and interventions to address their risks of developing disease (if they are in a high-risk group) and avoid unnecessary screening and interventions (if they are in a low-risk group). As it is likely that thousands of genetic variants contribute to CRC risk, it is clinically important to investigate whether these genetic variants can be used jointly for CRC risk prediction. In this paper, we derived and compared different approaches to generating predictive polygenic risk scores (PRS) from genome-wide association studies (GWASs) including 55,105 CRC-affected case subjects and 65,079 control subjects of European ancestry. We built the PRS in three ways, using (1) 140 previously identified and validated CRC loci; (2) SNP selection based on linkage disequilibrium (LD) clumping followed by machine-learning approaches; and (3) LDpred, a Bayesian approach for genome-wide risk prediction. We tested the PRS in an independent cohort of 101,987 individuals with 1,699 CRC-affected case subjects. The discriminatory accuracy, calculated by the age- and sex-adjusted area under the receiver operating characteristics curve (AUC), was highest for the LDpred-derived PRS (AUC = 0.654) including nearly 1.2 M genetic variants (the proportion of causal genetic variants for CRC assumed to be 0.003), whereas the PRS of the 140 known variants identified from GWASs had the lowest AUC (AUC = 0.629). Based on the LDpred-derived PRS, we are able to identify 30% of individuals without a family history as having risk for CRC similar to those with a family history of CRC, whereas the PRS based on known GWAS variants identified only top 10% as having a similar relative risk. About 90% of these individuals have no family history and would have been considered average risk under current screening guidelines, but might benefit from earlier screening. The developed PRS offers a way for risk-stratified CRC screening and other targeted interventions.


Assuntos
Neoplasias Colorretais/epidemiologia , Predisposição Genética para Doença , Genoma Humano/genética , Medição de Risco , Idoso , Grupo com Ancestrais do Continente Asiático/genética , Teorema de Bayes , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Herança Multifatorial/genética , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco
19.
Nat Commun ; 11(1): 3644, 2020 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32686686

RESUMO

Colorectal cancer (CRC) is a biologically heterogeneous disease. To characterize its mutational profile, we conduct targeted sequencing of 205 genes for 2,105 CRC cases with survival data. Our data shows several findings in addition to enhancing the existing knowledge of CRC. We identify PRKCI, SPZ1, MUTYH, MAP2K4, FETUB, and TGFBR2 as additional genes significantly mutated in CRC. We find that among hypermutated tumors, an increased mutation burden is associated with improved CRC-specific survival (HR = 0.42, 95% CI: 0.21-0.82). Mutations in TP53 are associated with poorer CRC-specific survival, which is most pronounced in cases carrying TP53 mutations with predicted 0% transcriptional activity (HR = 1.53, 95% CI: 1.21-1.94). Furthermore, we observe differences in mutational frequency of several genes and pathways by tumor location, stage, and sex. Overall, this large study provides deep insights into somatic mutations in CRC, and their potential relationships with survival and tumor features.


Assuntos
Neoplasias Colorretais/genética , Proteínas de Neoplasias/genética , Neoplasias do Colo/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação INDEL , Mutação , Prognóstico , Proteína Supressora de Tumor p53/genética
20.
Appl Physiol Nutr Metab ; 45(11): 1306-1309, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32569481

RESUMO

To determine associations between physical activity (PA), sedentary behavior (SB), and oxidative stress in colorectal cancer patients, ColoCare Study participants in Germany wore an accelerometer 6 and/or 12 months after surgery. Spearman partial correlations were used to assess associations between PA and urinary concentrations of oxidized guanine, a validated marker of oxidative stress. There were no significant associations between PA or SB and oxidized guanine in n = 76 measurements (ng/mg creatinine; r = 0.03, p = 0.76 for PA, r = -0.05, p = 0.69 for SB). Novelty Objectively measured PA was not associated with a marker of oxidative stress in colorectal cancer patients.

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