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2.
Hum Genet ; 138(4): 307-326, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30820706

RESUMEN

Genome-wide association studies have reported 56 independently associated colorectal cancer (CRC) risk variants, most of which are non-coding and believed to exert their effects by modulating gene expression. The computational method PrediXcan uses cis-regulatory variant predictors to impute expression and perform gene-level association tests in GWAS without directly measured transcriptomes. In this study, we used reference datasets from colon (n = 169) and whole blood (n = 922) transcriptomes to test CRC association with genetically determined expression levels in a genome-wide analysis of 12,186 cases and 14,718 controls. Three novel associations were discovered from colon transverse models at FDR ≤ 0.2 and further evaluated in an independent replication including 32,825 cases and 39,933 controls. After adjusting for multiple comparisons, we found statistically significant associations using colon transcriptome models with TRIM4 (discovery P = 2.2 × 10- 4, replication P = 0.01), and PYGL (discovery P = 2.3 × 10- 4, replication P = 6.7 × 10- 4). Interestingly, both genes encode proteins that influence redox homeostasis and are related to cellular metabolic reprogramming in tumors, implicating a novel CRC pathway linked to cell growth and proliferation. Defining CRC risk regions as one megabase up- and downstream of one of the 56 independent risk variants, we defined 44 non-overlapping CRC-risk regions. Among these risk regions, we identified genes associated with CRC (P < 0.05) in 34/44 CRC-risk regions. Importantly, CRC association was found for two genes in the previously reported 2q25 locus, CXCR1 and CXCR2, which are potential cancer therapeutic targets. These findings provide strong candidate genes to prioritize for subsequent laboratory follow-up of GWAS loci. This study is the first to implement PrediXcan in a large colorectal cancer study and findings highlight the utility of integrating transcriptome data in GWAS for discovery of, and biological insight into, risk loci.


Asunto(s)
Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Neoplasias Colorrectales/epidemiología , Expresión Génica , Regulación Neoplásica de la Expresión Génica , Frecuencia de los Genes , Estudio de Asociación del Genoma Completo/estadística & datos numéricos , Humanos , Valor Predictivo de las Pruebas , Pronóstico , Factores de Riesgo
3.
J Natl Cancer Inst ; 111(2): 146-157, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29917119

RESUMEN

BACKGROUND: Previous genome-wide association studies (GWAS) have identified 42 loci (P < 5 × 10-8) associated with risk of colorectal cancer (CRC). Expanded consortium efforts facilitating the discovery of additional susceptibility loci may capture unexplained familial risk. METHODS: We conducted a GWAS in European descent CRC cases and control subjects using a discovery-replication design, followed by examination of novel findings in a multiethnic sample (cumulative n = 163 315). In the discovery stage (36 948 case subjects/30 864 control subjects), we identified genetic variants with a minor allele frequency of 1% or greater associated with risk of CRC using logistic regression followed by a fixed-effects inverse variance weighted meta-analysis. All novel independent variants reaching genome-wide statistical significance (two-sided P < 5 × 10-8) were tested for replication in separate European ancestry samples (12 952 case subjects/48 383 control subjects). Next, we examined the generalizability of discovered variants in East Asians, African Americans, and Hispanics (12 085 case subjects/22 083 control subjects). Finally, we examined the contributions of novel risk variants to familial relative risk and examined the prediction capabilities of a polygenic risk score. All statistical tests were two-sided. RESULTS: The discovery GWAS identified 11 variants associated with CRC at P < 5 × 10-8, of which nine (at 4q22.2/5p15.33/5p13.1/6p21.31/6p12.1/10q11.23/12q24.21/16q24.1/20q13.13) independently replicated at a P value of less than .05. Multiethnic follow-up supported the generalizability of discovery findings. These results demonstrated a 14.7% increase in familial relative risk explained by common risk alleles from 10.3% (95% confidence interval [CI] = 7.9% to 13.7%; known variants) to 11.9% (95% CI = 9.2% to 15.5%; known and novel variants). A polygenic risk score identified 4.3% of the population at an odds ratio for developing CRC of at least 2.0. CONCLUSIONS: This study provides insight into the architecture of common genetic variation contributing to CRC etiology and improves risk prediction for individualized screening.


Asunto(s)
Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/genética , Etnicidad/genética , Sitios Genéticos , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Etnicidad/estadística & datos numéricos , Estudios de Seguimiento , Genotipo , Humanos , Pronóstico , Estados Unidos/epidemiología
4.
Cancer Causes Control ; 30(1): 103-112, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30542984

RESUMEN

PURPOSE: Tamoxifen is widely used to reduce the risk of breast cancer (BC) recurrence and extend disease-free survival among women with estrogen-sensitive breast cancers. Tamoxifen efficacy is thought to be attributable to its active metabolite, which is formed through a reaction catalyzed by the P450 enzyme, CYP2D6. Inhibition of tamoxifen metabolism as a result of germline genetic variation and/or use of CYP2D6-inhibiting medications ("inhibitors") is hypothesized to increase the risk of adverse BC outcomes among women taking tamoxifen. METHODS: The present cohort study of 960 women diagnosed with early-stage BC between 1993 and 1999 examined the association between concomitant use of CYP2D6 inhibitors and adjuvant tamoxifen and the risk of adverse BC outcomes (recurrence, second primary BC, BC mortality), both overall and according to CYP2D6 metabolic phenotype. RESULTS: Six or more months of CYP2D6 inhibitor use concomitant with tamoxifen was not associated with any appreciable increase in risk of recurrence or second primary BC or BC mortality, and there was no clear evidence of variation by CYP2D6 metabolic phenotype. CONCLUSIONS: These results are consistent with the relatively few other large, population-based studies conducted to date that have not observed an increased risk of adverse BC outcomes associated with CYP2D6 inhibition.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Citocromo P-450 CYP2D6/genética , Tamoxifeno/uso terapéutico , Anciano , Neoplasias de la Mama/genética , Estudios de Cohortes , Inhibidores del Citocromo P-450 CYP2D6/farmacología , Supervivencia sin Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Fenotipo
5.
Nat Genet ; 51(1): 76-87, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30510241

RESUMEN

To further dissect the genetic architecture of colorectal cancer (CRC), we performed whole-genome sequencing of 1,439 cases and 720 controls, imputed discovered sequence variants and Haplotype Reference Consortium panel variants into genome-wide association study data, and tested for association in 34,869 cases and 29,051 controls. Findings were followed up in an additional 23,262 cases and 38,296 controls. We discovered a strongly protective 0.3% frequency variant signal at CHD1. In a combined meta-analysis of 125,478 individuals, we identified 40 new independent signals at P < 5 × 10-8, bringing the number of known independent signals for CRC to ~100. New signals implicate lower-frequency variants, Krüppel-like factors, Hedgehog signaling, Hippo-YAP signaling, long noncoding RNAs and somatic drivers, and support a role for immune function. Heritability analyses suggest that CRC risk is highly polygenic, and larger, more comprehensive studies enabling rare variant analysis will improve understanding of biology underlying this risk and influence personalized screening strategies and drug development.


Asunto(s)
Neoplasias Colorrectales/genética , Predisposición Genética a la Enfermedad/genética , Polimorfismo de Nucleótido Simple/genética , Anciano , Estudios de Casos y Controles , Femenino , Estudio de Asociación del Genoma Completo/métodos , Genotipo , Humanos , Masculino , Persona de Mediana Edad , ARN Largo no Codificante/genética , Factores de Riesgo , Transducción de Señal/genética
6.
JCI Insight ; 3(14)2018 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-30046007

RESUMEN

BACKGROUND: Human papillomavirus-related (HPV-related) oropharyngeal squamous cell carcinomas (OPSCCs) have an excellent response rate to platinum-based chemoradiotherapy. Genomic differences between primary HPV-related OPSCCs that do or do not recur are unknown. Furthermore, it is unclear if HPV-related OPSCCs that recur share a genomic landscape with HPV-negative head and neck cancers (HNCs). METHODS: We utilized whole exome sequencing to analyze somatic nucleotide (SNVs) and copy number variants (CNVs) among a unique set of 51 primary HPV-related OPSCCs, including 35 that did not recur and 16 that recurred. We evaluated 12 metachronous recurrent OPSCCs (7 with paired primary OPSCCs) and 33 primary HPV-unrelated oral cavity and OPSCCs. RESULTS: KMT2D was the most frequently mutated gene among primary HPV-related OPSCCs (n = 51; 14%) and among metachronous recurrent OPSCCs (n = 12; 42%). Primary HPV-related OPSCCs that recurred shared a genomic landscape with primary HPV-related OPSCCs that did not recur. However, TSC2, BRIP1, NBN, and NFE2L2 mutations occurred in primary OPSCCs that recurred but not in those that did not recur. Moreover, primary HPV-related OPSCCs that recur harbor features of HPV-unrelated HNCs, notably including MAPK, JAK/STAT, and differentiation signaling pathway aberrations. Metachronous recurrent OPSCCs shared a genomic landscape with HPV-unrelated HNCs, including a high frequency of TP53, CASP8, FAT1, HLA-A, AJUBA, and NSD1 genomic alterations. CONCLUSION: Overall, primary HPV-related OPSCCs that recur share a genomic landscape with nonrecurrent OPSCCs. Metachronous recurrent OPSCCs share genomic features with HPV-negative HNCs. These data aim to guide future deescalation endeavors and functional experiments. FUNDING: This study is supported by the American Cancer Society (RSG TBG-123653), funding support for RAH (T32DC00018, Research Training in Otolaryngology, University of Washington), funds to EM from Seattle Translational Tumor Research (Fred Hutchinson Cancer Research Center), and center funds from the Fred Hutchinson Cancer Research Center to EM. UD is supported by the Department of Veterans Affairs, Biomedical Laboratory Research and Development (BLR&D), grant IO1-oo23456, and funds from the Pittsburgh Foundation and PNC Foundation.


Asunto(s)
Genes Virales/genética , Mutación , Neoplasias Orofaríngeas/virología , Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Carcinoma de Células Escamosas de Cabeza y Cuello/virología , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Variaciones en el Número de Copia de ADN , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/virología , Estados Unidos , Adulto Joven
7.
PLoS One ; 12(11): e0186518, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29161273

RESUMEN

BACKGROUND: The evaluation of less frequent genetic variants and their effect on complex disease pose new challenges for genomic research. To investigate whether epigenetic data can be used to inform aggregate rare-variant association methods (RVAM), we assessed whether variants more significantly associated with colorectal cancer (CRC) were preferentially located in non-coding regulatory regions, and whether enrichment was specific to colorectal tissues. METHODS: Active regulatory elements (ARE) were mapped using data from 127 tissues and cell-types from NIH Roadmap Epigenomics and Encyclopedia of DNA Elements (ENCODE) projects. We investigated whether CRC association p-values were more significant for common variants inside versus outside AREs, or 2) inside colorectal (CR) AREs versus AREs of other tissues and cell-types. We employed an integrative epigenomic RVAM for variants with allele frequency <1%. Gene sets were defined as ARE variants within 200 kilobases of a transcription start site (TSS) using either CR ARE or ARE from non-digestive tissues. CRC-set association p-values were used to evaluate enrichment of less frequent variant associations in CR ARE versus non-digestive ARE. RESULTS: ARE from 126/127 tissues and cell-types were significantly enriched for stronger CRC-variant associations. Strongest enrichment was observed for digestive tissues and immune cell types. CR-specific ARE were also enriched for stronger CRC-variant associations compared to ARE combined across non-digestive tissues (p-value = 9.6 × 10-4). Additionally, we found enrichment of stronger CRC association p-values for rare variant sets of CR ARE compared to non-digestive ARE (p-value = 0.029). CONCLUSIONS: Integrative epigenomic RVAM may enable discovery of less frequent variants associated with CRC, and ARE of digestive and immune tissues are most informative. Although distance-based aggregation of less frequent variants in CR ARE surrounding TSS showed modest enrichment, future association studies would likely benefit from joint analysis of transcriptomes and epigenomes to better link regulatory variation with target genes.


Asunto(s)
Neoplasias Colorrectales/genética , Epigenómica , Sitios de Carácter Cuantitativo/genética , Secuencias Reguladoras de Ácidos Nucleicos/genética , Neoplasias Colorrectales/patología , Frecuencia de los Genes , Estudio de Asociación del Genoma Completo , Genómica , Humanos , Polimorfismo de Nucleótido Simple
9.
Blood Adv ; 1(9): 535-544, 2017 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-29296973

RESUMEN

Burkitt lymphoma (BL), the most common pediatric cancer in sub-Saharan Africa, is a malignancy of antigen-experienced B lymphocytes. High-throughput sequencing (HTS) of the immunoglobulin heavy (IGH) and light chain (IGK/IGL) loci was performed on genomic DNA from 51 primary BL tumors: 19 from Uganda and 32 from Ghana. Reverse transcription polymerase chain reaction analysis and tumor RNA sequencing (RNAseq) was performed on the Ugandan tumors to confirm and extend the findings from the HTS of tumor DNA. Clonal IGH and IGK/IGL rearrangements were identified in 41 and 46 tumors, respectively. Evidence for rearrangement of the second IGH allele was observed in only 6 of 41 tumor samples with a clonal IGH rearrangement, suggesting that the normal process of biallelic IGHD to IGHJ diversity-joining (DJ) rearrangement is often disrupted in BL progenitor cells. Most tumors, including those with a sole dominant, nonexpressed DJ rearrangement, contained many IGH and IGK/IGL sequences that differed from the dominant rearrangement by < 10 nucleotides, suggesting that the target of ongoing mutagenesis of these loci in BL tumor cells is not limited to expressed alleles. IGHV usage in both BL tumor cohorts revealed enrichment for IGHV genes that are infrequently used in memory B cells from healthy subjects. Analysis of publicly available DNA sequencing and RNAseq data revealed that these same IGHV genes were overrepresented in dominant tumor-associated IGH rearrangements in several independent BL tumor cohorts. These data suggest that BL derives from an abnormal B-cell progenitor and that aberrant mutational processes are active on the immunoglobulin loci in BL cells.

10.
PLoS One ; 11(7): e0157521, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27379672

RESUMEN

Genome-wide association studies (GWAS) have identified many common single nucleotide polymorphisms (SNPs) associated with colorectal cancer risk. These SNPs may tag correlated variants with biological importance. Fine-mapping around GWAS loci can facilitate detection of functional candidates and additional independent risk variants. We analyzed 11,900 cases and 14,311 controls in the Genetics and Epidemiology of Colorectal Cancer Consortium and the Colon Cancer Family Registry. To fine-map genomic regions containing all known common risk variants, we imputed high-density genetic data from the 1000 Genomes Project. We tested single-variant associations with colorectal tumor risk for all variants spanning genomic regions 250-kb upstream or downstream of 31 GWAS-identified SNPs (index SNPs). We queried the University of California, Santa Cruz Genome Browser to examine evidence for biological function. Index SNPs did not show the strongest association signals with colorectal tumor risk in their respective genomic regions. Bioinformatics analysis of SNPs showing smaller P-values in each region revealed 21 functional candidates in 12 loci (5q31.1, 8q24, 11q13.4, 11q23, 12p13.32, 12q24.21, 14q22.2, 15q13, 18q21, 19q13.1, 20p12.3, and 20q13.33). We did not observe evidence of additional independent association signals in GWAS-identified regions. Our results support the utility of integrating data from comprehensive fine-mapping with expanding publicly available genomic databases to help clarify GWAS associations and identify functional candidates that warrant more onerous laboratory follow-up. Such efforts may aid the eventual discovery of disease-causing variant(s).


Asunto(s)
Neoplasias Colorrectales/genética , Predisposición Genética a la Enfermedad/genética , Variación Genética , Estudio de Asociación del Genoma Completo/métodos , Células A549 , Adulto , Anciano , Anciano de 80 o más Años , Células CACO-2 , Mapeo Cromosómico , Neoplasias Colorrectales/patología , Biología Computacional/métodos , Femenino , Genotipo , Células HCT116 , Células Hep G2 , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Sistema de Registros/estadística & datos numéricos , Factores de Riesgo , Adulto Joven
11.
Br J Cancer ; 114(2): 221-9, 2016 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-26766742

RESUMEN

BACKGROUND: Menopausal hormone therapy (MHT) use has been consistently associated with a decreased risk of colorectal cancer (CRC) in women. Our aim was to use a genome-wide gene-environment interaction analysis to identify genetic modifiers of CRC risk associated with use of MHT. METHODS: We included 10 835 postmenopausal women (5419 cases and 5416 controls) from 10 studies. We evaluated use of any MHT, oestrogen-only (E-only) and combined oestrogen-progestogen (E+P) hormone preparations. To test for multiplicative interactions, we applied the empirical Bayes (EB) test as well as the Wald test in conventional case-control logistic regression as primary tests. The Cocktail test was used as secondary test. RESULTS: The EB test identified a significant interaction between rs964293 at 20q13.2/CYP24A1 and E+P (interaction OR (95% CIs)=0.61 (0.52-0.72), P=4.8 × 10(-9)). The secondary analysis also identified this interaction (Cocktail test OR=0.64 (0.52-0.78), P=1.2 × 10(-5) (alpha threshold=3.1 × 10(-4)). The ORs for association between E+P and CRC risk by rs964293 genotype were as follows: C/C, 0.96 (0.61-1.50); A/C, 0.61 (0.39-0.95) and A/A, 0.40 (0.22-0.73), respectively. CONCLUSIONS: Our results indicate that rs964293 modifies the association between E+P and CRC risk. The variant is located near CYP24A1, which encodes an enzyme involved in vitamin D metabolism. This novel finding offers additional insight into downstream pathways of CRC etiopathogenesis.


Asunto(s)
Adenocarcinoma/genética , Neoplasias Colorrectales/genética , Terapia de Reemplazo de Estrógeno/métodos , Estrógenos/uso terapéutico , Progestinas/uso terapéutico , Vitamina D3 24-Hidroxilasa/genética , Adenocarcinoma/epidemiología , Anciano , Teorema de Bayes , Estudios de Casos y Controles , Neoplasias Colorrectales/epidemiología , Quimioterapia Combinada , Femenino , Interacción Gen-Ambiente , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Modelos Logísticos , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Factores de Riesgo
13.
Sci Transl Med ; 7(301): 301ra131, 2015 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-26290413

RESUMEN

The T cell receptor (TCR) protein is a heterodimer composed of an α chain and a ß chain. TCR genes undergo somatic DNA rearrangements to generate the diversity of T cell binding specificities needed for effective immunity. Recently, high-throughput immunosequencing methods have been developed to profile the TCR α (TCRA) and TCR ß (TCRB) repertoires. However, these methods cannot determine which TCRA and TCRB chains combine to form a specific TCR, which is essential for many functional and therapeutic applications. We describe and validate a method called pairSEQ, which can leverage the diversity of TCR sequences to accurately pair hundreds of thousands of TCRA and TCRB sequences in a single experiment. Our TCR pairing method uses standard laboratory consumables and equipment without the need for single-cell technologies. We show that pairSEQ can be applied to T cells from both blood and solid tissues, such as tumors.


Asunto(s)
Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T CD8-positivos/metabolismo , Humanos , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo
14.
Nat Commun ; 6: 7138, 2015 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-26151821

RESUMEN

Genetic susceptibility to colorectal cancer is caused by rare pathogenic mutations and common genetic variants that contribute to familial risk. Here we report the results of a two-stage association study with 18,299 cases of colorectal cancer and 19,656 controls, with follow-up of the most statistically significant genetic loci in 4,725 cases and 9,969 controls from two Asian consortia. We describe six new susceptibility loci reaching a genome-wide threshold of P<5.0E-08. These findings provide additional insight into the underlying biological mechanisms of colorectal cancer and demonstrate the scientific value of large consortia-based genetic epidemiology studies.


Asunto(s)
Neoplasias Colorrectales/genética , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Estudios de Casos y Controles , Humanos , Oportunidad Relativa , Polimorfismo de Nucleótido Simple
15.
JAMA ; 313(11): 1133-42, 2015 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-25781442

RESUMEN

IMPORTANCE: Use of aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with lower risk of colorectal cancer. OBJECTIVE: To identify common genetic markers that may confer differential benefit from aspirin or NSAID chemoprevention, we tested gene × environment interactions between regular use of aspirin and/or NSAIDs and single-nucleotide polymorphisms (SNPs) in relation to risk of colorectal cancer. DESIGN, SETTING, AND PARTICIPANTS: Case-control study using data from 5 case-control and 5 cohort studies initiated between 1976 and 2003 across the United States, Canada, Australia, and Germany and including colorectal cancer cases (n=8634) and matched controls (n=8553) ascertained between 1976 and 2011. Participants were all of European descent. EXPOSURES: Genome-wide SNP data and information on regular use of aspirin and/or NSAIDs and other risk factors. MAIN OUTCOMES AND MEASURES: Colorectal cancer. RESULTS: Regular use of aspirin and/or NSAIDs was associated with lower risk of colorectal cancer (prevalence, 28% vs 38%; odds ratio [OR], 0.69 [95% CI, 0.64-0.74]; P = 6.2 × 10(-28)) compared with nonregular use. In the conventional logistic regression analysis, the SNP rs2965667 at chromosome 12p12.3 near the MGST1 gene showed a genome-wide significant interaction with aspirin and/or NSAID use (P = 4.6 × 10(-9) for interaction). Aspirin and/or NSAID use was associated with a lower risk of colorectal cancer among individuals with rs2965667-TT genotype (prevalence, 28% vs 38%; OR, 0.66 [95% CI, 0.61-0.70]; P = 7.7 × 10(-33)) but with a higher risk among those with rare (4%) TA or AA genotypes (prevalence, 35% vs 29%; OR, 1.89 [95% CI, 1.27-2.81]; P = .002). In case-only interaction analysis, the SNP rs16973225 at chromosome 15q25.2 near the IL16 gene showed a genome-wide significant interaction with use of aspirin and/or NSAIDs (P = 8.2 × 10(-9) for interaction). Regular use was associated with a lower risk of colorectal cancer among individuals with rs16973225-AA genotype (prevalence, 28% vs 38%; OR, 0.66 [95% CI, 0.62-0.71]; P = 1.9 × 10(-30)) but was not associated with risk of colorectal cancer among those with less common (9%) AC or CC genotypes (prevalence, 36% vs 39%; OR, 0.97 [95% CI, 0.78-1.20]; P = .76). CONCLUSIONS AND RELEVANCE: In this genome-wide investigation of gene × environment interactions, use of aspirin and/or NSAIDs was associated with lower risk of colorectal cancer, and this association differed according to genetic variation at 2 SNPs at chromosomes 12 and 15. Validation of these findings in additional populations may facilitate targeted colorectal cancer prevention strategies.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Aspirina/uso terapéutico , Neoplasias Colorrectales/prevención & control , Interacción Gen-Ambiente , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Cromosomas Humanos Par 12 , Cromosomas Humanos Par 15 , Neoplasias Colorrectales/genética , Femenino , Marcadores Genéticos , Genotipo , Humanos , Masculino , Factores de Riesgo
16.
Inflamm Bowel Dis ; 21(1): 19-30, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25437819

RESUMEN

BACKGROUND: FOXP3 regulatory T cell prevent inflammation but are paradoxically increased in ulcerative colitis (UC). Local T-cell activation has been hypothesized to account for increased FOXP3 expression in colon lamina propria (LP) T cells. METHODS: To see if human FOXP3 LP T cells are an activated fraction of otherwise FOXP3 effector T cells and explore their clonal diversity in health and disease, we deep sequenced clonally unique T-cell receptor hypervariable regions of FOXP3 and FOXP3CD4 T-cell subpopulations from inflamed versus noninflamed colon LP or mesenteric lymph nodes of patients with or without UC. RESULTS: The clonal diversity of each LP T-cell population was not different between patients with versus without UC. Repertoire overlap was only seen between a minority of FOXP3 and FOXP3 cells, including recently activated CD38 cells and Th17-like CD161 effector T cells, but this repertoire overlap was not different between patients with versus without UC and was no larger than the overlap between Helios and Helios FOXP3 cells. CONCLUSIONS: Thus, at steady state, only a minority of FOXP3, and particularly Helios, T cells share a T-cell receptor sequence with FOXP3 effector populations in the colon LP, even in UC, revealing distinct clonal origins for LP regulatory T cell and effector T cells in humans.


Asunto(s)
Poliposis Adenomatosa del Colon/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Colitis Ulcerosa/inmunología , Factores de Transcripción Forkhead/metabolismo , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Linfocitos T Reguladores/inmunología , Poliposis Adenomatosa del Colon/metabolismo , Poliposis Adenomatosa del Colon/patología , Adolescente , Adulto , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/patología , Estudios de Casos y Controles , Células Cultivadas , Colitis Ulcerosa/metabolismo , Colitis Ulcerosa/patología , Femenino , Estudios de Seguimiento , Humanos , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Pronóstico , Análisis de Secuencia de ADN , Linfocitos T Reguladores/metabolismo , Linfocitos T Reguladores/patología , Adulto Joven
17.
Cancer Inform ; 13(Suppl 2): 5-17, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25288875

RESUMEN

Most cancer-associated genetic variants identified from genome-wide association studies (GWAS) do not obviously change protein structure, leading to the hypothesis that the associations are attributable to regulatory polymorphisms. Translating genetic associations into mechanistic insights can be facilitated by knowledge of the causal regulatory variant (or variants) responsible for the statistical signal. Experimental validation of candidate functional variants is onerous, making bioinformatic approaches necessary to prioritize candidates for laboratory analysis. Thus, a systematic approach for recognizing functional (and, therefore, likely causal) variants in noncoding regions is an important step toward interpreting cancer risk loci. This review provides a detailed introduction to current regulatory variant annotations, followed by an overview of how to leverage these resources to prioritize candidate functional polymorphisms in regulatory regions.

18.
Cancer Epidemiol Biomarkers Prev ; 23(12): 2971-6, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25192705

RESUMEN

BACKGROUND: Calcium intake may reduce risk of colorectal cancer, but the mechanisms remain unclear. Studies of interaction between calcium intake and SNPs in calcium-related pathways have yielded inconsistent results. METHODS: To identify gene-calcium interactions, we tested interactions between approximately 2.7 million SNPs across the genome with self-reported calcium intake (from dietary or supplemental sources) in 9,006 colorectal cancer cases and 9,503 controls of European ancestry. To test for multiplicative interactions, we used multivariable logistic regression and defined statistical significance using the conventional genome-wide α = 5E-08. RESULTS: After accounting for multiple comparisons, there were no statistically significant SNP interactions with total, dietary, or supplemental calcium intake. CONCLUSIONS: We found no evidence of SNP interactions with calcium intake for colorectal cancer risk in a large population of 18,509 individuals. IMPACT: These results suggest that in genome-wide analysis common genetic variants do not strongly modify the association between calcium intake and colorectal cancer in European populations.


Asunto(s)
Calcio de la Dieta/uso terapéutico , Neoplasias Colorrectales/genética , Polimorfismo de Nucleótido Simple/genética , Neoplasias Colorrectales/epidemiología , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Factores de Riesgo
19.
Cancer Epidemiol Biomarkers Prev ; 23(9): 1824-33, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24994789

RESUMEN

BACKGROUND: Genome-wide association studies have identified several single nucleotide polymorphisms (SNPs) that are associated with risk of colorectal cancer. Prior research has evaluated the presence of gene-environment interaction involving the first 10 identified susceptibility loci, but little work has been conducted on interaction involving SNPs at recently identified susceptibility loci, including: rs10911251, rs6691170, rs6687758, rs11903757, rs10936599, rs647161, rs1321311, rs719725, rs1665650, rs3824999, rs7136702, rs11169552, rs59336, rs3217810, rs4925386, and rs2423279. METHODS: Data on 9,160 cases and 9,280 controls from the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO) and Colon Cancer Family Registry (CCFR) were used to evaluate the presence of interaction involving the above-listed SNPs and sex, body mass index (BMI), alcohol consumption, smoking, aspirin use, postmenopausal hormone (PMH) use, as well as intake of dietary calcium, dietary fiber, dietary folate, red meat, processed meat, fruit, and vegetables. Interaction was evaluated using a fixed effects meta-analysis of an efficient Empirical Bayes estimator, and permutation was used to account for multiple comparisons. RESULTS: None of the permutation-adjusted P values reached statistical significance. CONCLUSIONS: The associations between recently identified genetic susceptibility loci and colorectal cancer are not strongly modified by sex, BMI, alcohol, smoking, aspirin, PMH use, and various dietary factors. IMPACT: Results suggest no evidence of strong gene-environment interactions involving the recently identified 16 susceptibility loci for colorectal cancer taken one at a time.


Asunto(s)
Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/genética , Interacción Gen-Ambiente , Estudio de Asociación del Genoma Completo/métodos , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Dieta/estadística & datos numéricos , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Adulto Joven
20.
PLoS Genet ; 10(4): e1004228, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24743840

RESUMEN

Dietary factors, including meat, fruits, vegetables and fiber, are associated with colorectal cancer; however, there is limited information as to whether these dietary factors interact with genetic variants to modify risk of colorectal cancer. We tested interactions between these dietary factors and approximately 2.7 million genetic variants for colorectal cancer risk among 9,287 cases and 9,117 controls from ten studies. We used logistic regression to investigate multiplicative gene-diet interactions, as well as our recently developed Cocktail method that involves a screening step based on marginal associations and gene-diet correlations and a testing step for multiplicative interactions, while correcting for multiple testing using weighted hypothesis testing. Per quartile increment in the intake of red and processed meat were associated with statistically significant increased risks of colorectal cancer and vegetable, fruit and fiber intake with lower risks. From the case-control analysis, we detected a significant interaction between rs4143094 (10p14/near GATA3) and processed meat consumption (OR = 1.17; p = 8.7E-09), which was consistently observed across studies (p heterogeneity = 0.78). The risk of colorectal cancer associated with processed meat was increased among individuals with the rs4143094-TG and -TT genotypes (OR = 1.20 and OR = 1.39, respectively) and null among those with the GG genotype (OR = 1.03). Our results identify a novel gene-diet interaction with processed meat for colorectal cancer, highlighting that diet may modify the effect of genetic variants on disease risk, which may have important implications for prevention.


Asunto(s)
Neoplasias Colorrectales/etiología , Neoplasias Colorrectales/genética , Dieta/efectos adversos , Adulto , Anciano , Estudios de Casos y Controles , Fibras de la Dieta/administración & dosificación , Femenino , Frutas , Estudio de Asociación del Genoma Completo/métodos , Genotipo , Humanos , Masculino , Carne/efectos adversos , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Riesgo , Factores de Riesgo , Verduras , Adulto Joven
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