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1.
Cancers (Basel) ; 14(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36358697

RESUMO

Background: Chronic hepatitis C virus (HCV) infection can affect immune response and inflammatory pathways, leading to severe liver diseases such as cirrhosis and hepatocellular carcinoma (HCC). Methods: In a prospective cohort of chronically HCV-infected individuals, we sampled 68 individuals who developed cirrhosis, 91 controls who did not develop cirrhosis, and 94 individuals who developed HCC. Unconditional odds ratios (ORs) from polytomous logistic regression models and canonical discriminant analyses (CDAs) were used to compare categorical (C) baseline plasma levels for 102 markers in individuals who developed cirrhosis vs. controls and those who developed HCC vs. cirrhosis. Leave-one-out cross validation was used to produce receiver operating characteristic curves to assess predictive ability of markers. Lastly, biological pathways were assessed in association with cirrhotic development compared to controls. Results: After multivariable adjustment, DEFA-1 (OR: C2v.C1 = 7.73; p < 0.0001), ITGAM (OR: C2v.C1 = 4.03; p = 0.0002), SCF (OR: C4v.C1 = 0.19; p-trend = 0.0001), and CCL11 (OR: C4v.C1 = 0.31; p-trend= 0.002) were all associated with development of cirrhosis compared to controls; these markers, together with clinical/demographics variables, improved prediction of cirrhosis from 55.7% (in clinical/demographic-only model) to 74.9% accuracy. A twelve-marker model based on CDA results further increased prediction of cirrhosis to 88.0%. While six biological pathways were found to be associated with cirrhosis, cell adhesion was the only pathway associated with cirrhosis after Bonferroni correction. In contrast to cirrhosis, DEFA-1 and ITGAM levels were inversely associated with HCC risk. Conclusions: Pending validation, these findings highlight the important role of immunological markers in predicting HCV-related cirrhosis even 11 years post-enrollment.

2.
Sci Rep ; 11(1): 21194, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34782638

RESUMO

Host immune response and chronic inflammation associated with chronic hepatitis B virus (HBV) infection play a key role in the pathogenesis of liver diseases such as cirrhosis and hepatocellular carcinoma (HCC). We sampled 175 HCC, 117 cirrhotic and 165 non-cirrhotic controls from a prospective cohort study of chronically HBV-infected individuals. Multivariable polytomous logistic regression and canonical discriminant analysis (CDA) were used to compare baseline plasma levels for 102 markers in individuals who developed cirrhosis vs. controls and those who developed HCC vs. cirrhosis. Leave-one-out cross validation was used to generate receiver operating characteristic curves to compare the predictive ability of marker groups. After multivariable adjustment, HGF (Q4v1OR: 3.74; p-trend = 0.0001), SLAMF1 (Q4v1OR: 4.07; p-trend = 0.0001), CSF1 (Q4v1OR: 3.00; p-trend = 0.002), uPA (Q4v1OR: 3.36; p-trend = 0.002), IL-8 (Q4v1OR: 2.83; p-trend = 0.004), and OPG (Q4v1OR: 2.44; p-trend = 0.005) were all found to be associated with cirrhosis development compared to controls; these markers predicted cirrhosis with 69% accuracy. CDA analysis identified a nine marker model capable of predicting cirrhosis development with 79% accuracy. No markers were significantly different between HCC and cirrhotic participants. In this study, we assessed immunologic markers in relation to liver disease in chronically-HBV infected individuals. While validation in required, these findings highlight the importance of immunologic processes in HBV-related cirrhosis.


Assuntos
Biomarcadores/metabolismo , Carcinoma Hepatocelular/epidemiologia , Hepatite B Crônica/epidemiologia , Cirrose Hepática/epidemiologia , Neoplasias Hepáticas/epidemiologia , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
3.
Front Public Health ; 8: 330, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33014952

RESUMO

Hispanics/Latinos are expected to constitute 25% of the U.S. population by 2060. Differences in the prevalence of health risk factors, chronic diseases, and access to and utilization of health-care services between Hispanics/Latinos and other populations in the U.S. have been documented. This study aimed to describe and analyze the landscape of Research Program Grants (RPGs) funded by the National Institutes of Health (NIH) between 2008 and 2015 involving Hispanic/Latino health research in six health condition areas-asthma, cancer, dementia, diabetes, liver/gallbladder disease, and obesity-and to identify opportunities for continued research in these areas. Using an NIH internal search engine, we identified new and renewal Hispanic/Latino health RPGs searching for specific Hispanic/Latino identifiers in the Title, Abstract, and Specific Aims. We used descriptive statistics to examine the distribution of funded RPGs by NIH disease-based classification codes for the six health condition areas of interest, and other selected characteristics. The most prominent clusters of research subtopics were identified within each health condition area, and performance sites were mapped at the city level. Within the selected time frame, 3,221 Hispanic/Latino health-related unique RPGs were funded (constituting 4.4% of all funded RPGs), and of those 625 RPGs were eligible for review and coding in the present study. Cancer and obesity were the most commonly studied health condition areas (72%), while studies on mechanisms of disease-biological and non-biological-(72.6%), behavioral research (42.1%) and epidemiological studies (38.1%) were the most common types of research. Most of the primary performance sites were in California, Texas, the northeastern U.S., and Illinois. The predominance of mechanistic, behavioral, and epidemiological studies in our analysis poses opportunities to evaluate knowledge gained and their clinical application, explore new research questions, or to update some methods or instruments. The findings of the present study suggest opportunities to expand research in understudied mechanisms of disease that could explain differences in prevalence of conditions like diabetes and cancer among different heritage groups. In addition, our findings suggest that the impact of interventions or policies designed to reduce health disparities, innovative multi-level interventions, implementation and dissemination studies, the role of health information technology on health outcomes, and the intersectionality of individual, sociocultural, geographic, and other factors on health outcomes, among others, are understudied approaches, which could potentially advance research in Hispanic/Latino health and contribute to the achievement of better health outcomes in this diverse population.


Assuntos
Hispânico ou Latino , National Institutes of Health (U.S.) , Organização do Financiamento , Humanos , Illinois , Texas , Estados Unidos/epidemiologia
4.
Cancer Epidemiol Biomarkers Prev ; 29(8): 1519-1534, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32467344

RESUMO

The application of next-generation sequencing (NGS) technologies in cancer research has accelerated the discovery of somatic mutations; however, progress in the identification of germline variation associated with cancer risk is less clear. We conducted a systematic literature review of cancer genetic susceptibility studies that used NGS technologies at an exome/genome-wide scale to obtain a fuller understanding of the research landscape to date and to inform future studies. The variability across studies on methodologies and reporting was considerable. Most studies sequenced few high-risk (mainly European) families, used a candidate analysis approach, and identified potential cancer-related germline variants or genes in a small fraction of the sequenced cancer cases. This review highlights the importance of establishing consensus on standards for the application and reporting of variants filtering strategies. It also describes the progress in the identification of cancer-related germline variation to date. These findings point to the untapped potential in conducting studies with appropriately sized and racially diverse families and populations, combining results across studies and expanding beyond a candidate analysis approach to advance the discovery of genetic variation that accounts for the unexplained cancer heritability.


Assuntos
Exoma/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos
5.
J Epidemiol Community Health ; 72(12): 1076-1082, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30100578

RESUMO

BACKGROUND: Vitamin C insufficiency occurs across many countries and has been hypothesised to increase risk of various diseases. Few prospective studies with measured circulating vitamin C have related deficiency to disease mortality, particularly in low-income and middle-income countries. METHODS: We randomly selected 948 subjects (473 males and 475 females) aged 53-84 years from a Chinese cohort and measured meta-phosphoric acid-preserved vitamin C concentrations in plasma samples collected in 1999-2000. A total of 551 deaths were accrued from sample collection through 2016, including 141 from cancer, 170 from stroke and 174 from heart diseases. Vitamin C was analysed using season-specific quartiles, as a continuous variable and as a dichotomous variable based on sufficiency status (normal >28 µmol/L vs low ≤28 µmol/L). HRs and 95% CIs were estimated using Cox proportional hazards models. RESULTS: We found significant inverse associations between higher plasma vitamin C concentrations and total mortality in quartile (HRQ4 vs Q10.75, 95% CI 0.59 to 0.95), continuous (HRq20umol/L0.90, 95% CI 0.82 to 0.99) and dichotomous analyses (HRnormal-vs-low0.77, 95% CI 0.63 to 0.95). We observed significant lower risks of heart disease (ptrend-by-quantile=0.03) and cancer deaths (pglobal-across-quantile=0.04) for higher vitamin C, whereas the association was attenuated for stroke in adjusted models. Similar inverse associations were found when comparing normal versus low vitamin C for heart disease (HRnormal-vs-low0.62, 95% CI 0.42 to 0.89). CONCLUSION: In this long-term prospective Chinese cohort study, higher plasma vitamin C concentration was associated with lower total mortality, heart disease mortality and cancer mortality. Our results corroborate the importance of adequate vitamin C to human health.


Assuntos
Ácido Ascórbico/sangue , Mortalidade/tendências , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Doenças Cardiovasculares/mortalidade , Causas de Morte , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/mortalidade , Estudos Prospectivos , Estações do Ano
6.
Cancer Epidemiol Biomarkers Prev ; 26(6): 826-836, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28077426

RESUMO

Background: Epidemiologic evidence on the association between nut consumption and lung cancer risk is limited.Methods: We investigated this relationship in the Environment and Genetics in Lung Cancer Etiology (EAGLE) study, a population-based case-control study, and the National Institutes of Health (NIH) American Association of Retired Persons (AARP) Diet and Health Study, a prospective cohort. We identified 2,098 lung cases for EAGLE and 18,533 incident cases in AARP. Diet was assessed by food frequency questionnaire for both studies. Multivariable ORs and HRs and respective 95% confidence intervals (CI) were calculated using unconditional logistic regression and Cox proportional hazards regression for EAGLE and AARP, respectively.Results: Higher frequency of intake of nut consumption was inversely associated with overall lung cancer risk (highest vs. lowest quintile, OREAGLE = 0.74; 95% CI, 0.57-0.95; HRAARP = 0.86; 95% CI, 0.81-0.91), regardless of smoking status. Results from the prospective cohort showed similar associations across histologic subtypes and a more pronounced benefits from nut consumption for those who smoked 1 to 20 cigarettes/day (OREAGLE = 0.61; 95% CI, 0.39-0.95; HRAARP = 0.83; 95% CI, 0.74-0.94).Conclusions: Nut consumption was inversely associated with lung cancer in two large population-based studies, and associations were independent of cigarette smoking and other known risk factors.Impact: To our knowledge, this is the first study that examined the association between nut consumption and lung cancer risk by histologic subtypes and smoking intensity. Cancer Epidemiol Biomarkers Prev; 26(6); 826-36. ©2017 AACR.


Assuntos
Neoplasias Pulmonares/etiologia , Nozes/efeitos adversos , Estudos de Casos e Controles , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco
7.
Cancer Causes Control ; 28(1): 5-12, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27900614

RESUMO

In order to capture trends in the contribution of epidemiology to cancer research, we describe an online meta-analysis database resource for cancer clinical and population research and illustrate trends and descriptive detail of cancer meta-analyses from 2008 through 2013. A total of 4,686 cancer meta-analyses met our inclusion criteria. During this 6-year period, a fivefold increase was observed in the yearly number of meta-analyses. Fifty-six percent of meta-analyses concerned observational studies, mostly of cancer risk, more than half of which were genetic studies. The major cancer sites were breast, colorectal, and digestive. This online database for Cancer Genomics and Epidemiology Navigator will be continuously updated to allow investigators to quickly navigate the meta-analyses emerging from cancer epidemiology studies and cancer clinical trials.


Assuntos
Metanálise como Assunto , Neoplasias , Editoração/tendências , Pesquisa , Humanos
8.
Cancer Epidemiol Biomarkers Prev ; 25(4): 573-80, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27196089

RESUMO

Medically underserved populations in the United States continue to experience higher cancer burdens of incidence, mortality, and other cancer-related outcomes. It is imperative to understand how health inequities experienced by diverse population groups may contribute to our increasing unequal cancer burdens and disparate outcomes. The National Cancer Institute convened a diverse group of scientists to discuss research challenges and opportunities for cancer epidemiology in medically underserved and understudied populations. This report summarizes salient issues and discusses five recommendations from the group, including the next steps required to better examine and address cancer burden in the United States among our rapidly increasing diverse and understudied populations. Cancer Epidemiol Biomarkers Prev; 25(4); 573-80. ©2016 AACR SEE ALL ARTICLES IN THIS CEBP FOCUS SECTION, "MULTILEVEL APPROACHES TO ADDRESSING CANCER HEALTH DISPARITIES".


Assuntos
Estudos Epidemiológicos , Grupos Minoritários/estatística & dados numéricos , Neoplasias/epidemiologia , Humanos
9.
BMC Clin Pathol ; 15: 6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25883534

RESUMO

Both normal and diseased cells continuously shed extracellular vesicles (EVs) into extracellular space, and the EVs carry molecular signatures and effectors of both health and disease. EVs reflect dynamic changes that are occurring in cells and tissue microenvironment in health and at a different stage of a disease. EVs are capable of altering the function of the recipient cells. Trafficking and reciprocal exchange of molecular information by EVs among different organs and cell types have been shown to contribute to horizontal cellular transformation, cellular reprogramming, functional alterations, and metastasis. EV contents may include tumor suppressors, phosphoproteins, proteases, growth factors, bioactive lipids, mutant oncoproteins, oncogenic transcripts, microRNAs, and DNA sequences. Therefore, the EVs present in biofluids offer unprecedented, remote, and non-invasive access to crucial molecular information about the health status of cells, including their driver mutations, classifiers, molecular subtypes, therapeutic targets, and biomarkers of drug resistance. In addition, EVs may offer a non-invasive means to assess cancer initiation, progression, risk, survival, and treatment outcomes. The goal of this review is to highlight the current status of information on the role of EVs in cancer, and to explore the utility of EVs for cancer diagnosis, prognosis, and epidemiology.

11.
Am J Epidemiol ; 181(7): 451-8, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25767265

RESUMO

Concurrently with a workshop sponsored by the National Cancer Institute, we identified key "drivers" for accelerating cancer epidemiology across the translational research continuum in the 21st century: emerging technologies, a multilevel approach, knowledge integration, and team science. To map the evolution of these "drivers" and translational phases (T0-T4) in the past decade, we analyzed cancer epidemiology grants funded by the National Cancer Institute and published literature for 2000, 2005, and 2010. For each year, we evaluated the aims of all new/competing grants and abstracts of randomly selected PubMed articles. Compared with grants based on a single institution, consortium-based grants were more likely to incorporate contemporary technologies (P = 0.012), engage in multilevel analyses (P = 0.010), and incorporate elements of knowledge integration (P = 0.036). Approximately 74% of analyzed grants and publications involved discovery (T0) or characterization (T1) research, suggesting a need for more translational (T2-T4) research. Our evaluation indicated limited research in 1) a multilevel approach that incorporates molecular, individual, social, and environmental determinants and 2) knowledge integration that evaluates the robustness of scientific evidence. Cancer epidemiology is at the cusp of a paradigm shift, and the field will need to accelerate the pace of translating scientific discoveries in order to impart population health benefits. While multi-institutional and technology-driven collaboration is happening, concerted efforts to incorporate other key elements are warranted for the discipline to meet future challenges.


Assuntos
Tecnologia Biomédica/tendências , National Cancer Institute (U.S.)/tendências , Neoplasias/epidemiologia , Apoio à Pesquisa como Assunto/tendências , Pesquisa Translacional Biomédica/tendências , Tecnologia Biomédica/economia , Métodos Epidemiológicos , Financiamento Governamental , Humanos , Análise Multinível , National Cancer Institute (U.S.)/economia , National Cancer Institute (U.S.)/normas , Neoplasias/economia , Apoio à Pesquisa como Assunto/economia , Pesquisa Translacional Biomédica/economia , Pesquisa Translacional Biomédica/métodos , Estados Unidos
13.
Genet Med ; 17(6): 431-40, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25341115

RESUMO

PURPOSE: To understand the translational trajectory of genomic tests in cancer screening, diagnosis, prognosis, and treatment, we reviewed tests that have been assessed by recommendation and guideline developers. METHODS: For each test, we marked translational milestones by determining when the genomic association with cancer was first discovered and studied in patients, and when a health application for a specified clinical use was successfully demonstrated and approved or cleared by the US Food and Drug Administration. To identify recommendations and guidelines, we reviewed the websites of cancer, genomic, and general guideline developers and professional organizations. We searched the in vitro diagnostics database of the US Food and Drug Administration for information, and we searched PubMed for translational milestones. Milestones were examined against type of recommendation, Food and Drug Administration approval or clearance, disease rarity, and test purpose. RESULTS: Of the 45 tests we identified, 9 received strong recommendations for their usage in clinical settings, 14 received positive but moderate recommendations, and 22 were not currently recommended. For 18 tests, two or more different sources had issued recommendations, with 67% concordance. Only five tests had Food and Drug Administration approval, and an additional five had clearance. The median time from discovery to recommendation statement was 14.7 years. CONCLUSION: In general, there were no associations found between translational trajectory and recommendation category.Genet Med 17 6, 431-440.


Assuntos
Testes Genéticos/métodos , Genômica/métodos , Neoplasias/diagnóstico , Neoplasias/genética , Pesquisa Translacional Biomédica/métodos , Aprovação de Teste para Diagnóstico , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/normas , Testes Genéticos/normas , Genômica/normas , Humanos , Pesquisa Translacional Biomédica/normas , Estados Unidos , United States Food and Drug Administration
14.
Genet Med ; 17(1): 63-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24946156

RESUMO

PURPOSE: With the accelerated implementation of genomic medicine, health-care providers will depend heavily on professional guidelines and recommendations. Because genomics affects many diseases across the life span, no single professional group covers the entirety of this rapidly developing field. METHODS: To pursue a discussion of the minimal elements needed to develop evidence-based guidelines in genomics, the Centers for Disease Control and Prevention and the National Cancer Institute jointly held a workshop to engage representatives from 35 organizations with interest in genomics (13 of which make recommendations). The workshop explored methods used in evidence synthesis and guideline development and initiated a dialogue to compare these methods and to assess whether they are consistent with the Institute of Medicine report "Clinical Practice Guidelines We Can Trust." RESULTS: The participating organizations that develop guidelines or recommendations all had policies to manage guideline development and group membership, and processes to address conflicts of interests. However, there was wide variation in the reliance on external reviews, regular updating of recommendations, and use of systematic reviews to assess the strength of scientific evidence. CONCLUSION: Ongoing efforts are required to establish criteria for guideline development in genomic medicine as proposed by the Institute of Medicine.


Assuntos
Medicina Baseada em Evidências , Genômica , Guias de Prática Clínica como Assunto , Medicina Baseada em Evidências/métodos , Medicina Baseada em Evidências/tendências , Genômica/métodos , Genômica/tendências , Humanos
16.
Am J Epidemiol ; 180(10): 964-7, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25234430

RESUMO

There is expanding consensus on the need to modernize the training of cancer epidemiologists to accommodate rapidly emerging technological advancements and the digital age, which are transforming the practice of cancer epidemiology. There is also a growing imperative to extend cancer epidemiology research that is etiological to that which is applied and has the potential to affect individual and public health. Medical schools and schools of public health are recognizing the need to develop such integrated programs; however, we lack the data to estimate how many current training programs are effectively equipping epidemiology students with the knowledge and tools to design, conduct, and analyze these increasingly complex studies. There is also a need to develop new mentoring approaches to account for the transdisciplinary team-science environment that now prevails. With increased dialogue among schools of public health, medical schools, and cancer centers, revised competencies and training programs at predoctoral, doctoral, and postdoctoral levels must be developed. Continuous collection of data on the impact and outcomes of such programs is also recommended.


Assuntos
Epidemiologia/educação , Neoplasias/prevenção & controle , Competência Profissional , Humanos , Comunicação Interdisciplinar , Neoplasias/epidemiologia , Estados Unidos/epidemiologia
17.
Mol Carcinog ; 53(7): 548-56, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23681825

RESUMO

Lung cancer causes more deaths worldwide than any other cancer. In addition to cigarette smoking, dietary factors may contribute to lung carcinogenesis. Epidemiologic studies, including the environment and genetics in lung cancer etiology (EAGLE), have reported increased consumption of red/processed meats to be associated with higher risk of lung cancer. Heme-iron toxicity may link meat intake with cancer. We investigated this hypothesis in meat-related lung carcinogenesis using whole genome expression. We measured genome-wide expression (HG-U133A) in 49 tumor and 42 non-involved fresh frozen lung tissues of 64 adenocarcinoma EAGLE patients. We studied gene expression profiles by high-versus-low meat consumption, with and without adjustment by sex, age, and smoking. Threshold for significance was a false discovery rate (FDR) ≤ 0.15. We studied whether the identified genes played a role in heme-iron related processes by means of manually curated literature search and gene ontology-based pathway analysis. We found that gene expression of 232 annotated genes in tumor tissue significantly distinguished lung adenocarcinoma cases who consumed above/below the median intake of fresh red meats (FDR = 0.12). Sixty-three (∼ 28%) of the 232 identified genes (12 expected by chance, P-value < 0.001) were involved in heme binding, absorption, transport, and Wnt signaling pathway (e.g., CYPs, TPO, HPX, HFE, SLCs, and WNTs). We also identified several genes involved in lipid metabolism (e.g., NCR1, TNF, and UCP3) and oxidative stress (e.g., TPO, SGK2, and MTHFR) that may be indirectly related to heme-toxicity. The study's results provide preliminary evidence that heme-iron toxicity might be one underlying mechanism linking fresh red meat intake and lung cancer.


Assuntos
Adenocarcinoma/genética , Carcinogênese/genética , Ingestão de Alimentos , Heme , Ferro da Dieta/efeitos adversos , Neoplasias Pulmonares/genética , Carne/efeitos adversos , Adenocarcinoma de Pulmão , Idoso , Estudos de Casos e Controles , Dieta , Comportamento Alimentar , Feminino , Perfilação da Expressão Gênica , Humanos , Metabolismo dos Lipídeos/genética , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/genética , Ligação Proteica/genética , Transporte Proteico/genética , Risco , Fatores de Risco , Via de Sinalização Wnt/genética
18.
Am J Clin Nutr ; 98(5): 1289-97, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24025629

RESUMO

BACKGROUND: China has some of the highest incidence rates for gastric adenocarcinoma (GA) and esophageal squamous cell carcinoma (ESCC) in the world. Prospective studies suggested that vitamin C may reduce risks; however, associations are unclear because of limited sample size. OBJECTIVE: The objective was to examine the relation between prediagnostic plasma vitamin C and the risk of GA and ESCC. DESIGN: A case-cohort study was used to assess the association between prediagnostic plasma vitamin C and incidence of GA (n = 467) and ESCC (n = 618) in the General Population Nutrition Intervention Trial. With the use of multivariate Cox proportional hazards models, we estimated the HRs and 95% CIs. We also conducted a meta-analysis of the literature up to 1 October 2012 on the relation between circulating vitamin C and gastric cancer incidence. Two cohort studies and the current study were included to assess the body of evidence. RESULTS: For GA, each 20-µmol/L increase in plasma vitamin C was associated with a 14% decrease in risk (HR: 0.86; 95% CI: 0.76, 0.96). Compared with individuals with low plasma vitamin C concentrations (≤28 µmol/L), those with normal concentrations (>28 µmol/L) had a 27% reduced risk of GA (HR: 0.73; 95% CI: 0.56, 0.94). No association between vitamin C concentrations and ESCC was seen. Meta-analysis showed that the risk of incident GA among those with the highest concentration of plasma vitamin C was 31% lower (random-effects-pooled-odds ratio 0.69; 95% CI: 0.54, 0.89) than those in the lowest category. CONCLUSION: Our data provide evidence that higher circulating vitamin C was associated with a reduced risk of incident GA, but no association was seen for ESCC.


Assuntos
Ácido Ascórbico/sangue , Povo Asiático , Carcinoma de Células Escamosas/epidemiologia , Neoplasias Esofágicas/epidemiologia , Neoplasias Gástricas/epidemiologia , Ácido Ascórbico/administração & dosagem , Carcinoma de Células Escamosas/prevenção & controle , China/epidemiologia , Neoplasias Esofágicas/prevenção & controle , Carcinoma de Células Escamosas do Esôfago , Humanos , Incidência , Razão de Chances , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Neoplasias Gástricas/prevenção & controle
19.
PLoS One ; 8(8): e70672, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23940620

RESUMO

Worldwide, lung cancer in never-smokers is ranked the seventh most common cause of cancer death; however, the etiology of lung cancer in never-smokers is unclear. We investigated associations for body mass index (BMI) at various ages, waist circumference, hip circumference, and physical activity with lung cancer in 158,415 never-smokers of the NIH-AARP Diet and Health Study. Multivariable hazard ratios (HR) and 95% confidence intervals (CI) were estimated from Cox proportional hazards models. Over 11 years of follow-up, 532 lung cancer cases occurred. The risk estimate for obese (BMI ≥ 30 kg/m(2)) participants at baseline was 1.21 (95%CI = 0.95-1.53) relative to those with a normal BMI between 18.5 ≤ BMI<25.0. Overweight (25.0 ≤ BMI<30.0) at age 18 (HR(overweight-vs-normal) = 1.51;95%CI = 1.01-2.26) and time spent sitting (HR(≥ 3 hrs-vs-<3 hrs) = 1.32;95%CI = 1.00-1.73) was each associated with lung cancer after adjustment for baseline BMI, as was waist (HR(Q4-vs-Q1) = 1.75;95%CI = 1.09-2.79) and hip circumference (HRQ4-vs-Q1 = 0.62;95%CI = 0.39-0.99), after mutual adjustment for each other and baseline BMI. No associations were observed for vigorous activity or television watching. In summary, using a large prospective cohort study, we found no evidence that BMI at baseline or middle age was associated with decreased lung cancer risk in never smokers. If anything, we observed some evidence for positive associations with a larger BMI or waist circumference.


Assuntos
Adenocarcinoma/epidemiologia , Exercício Físico , Neoplasias Pulmonares/epidemiologia , Adenocarcinoma/etiologia , Idoso , Índice de Massa Corporal , Feminino , Humanos , Incidência , Neoplasias Pulmonares/etiologia , Masculino , Pessoa de Meia-Idade , Sobrepeso/complicações , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários , Circunferência da Cintura
20.
PLoS One ; 8(6): e65602, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23776510

RESUMO

Meta-analyses are increasingly popular. It is unknown whether this popularity is driven by specific countries and specific meta-analyses types. PubMed was used to identify meta-analyses since 1995 (last update 9/1/2012) and catalogue their types and country of origin. We focused more on meta-analyses from China (the current top producer of meta-analyses) versus the USA (top producer until recently). The annual number of meta-analyses from China increased 40-fold between 2003 and 2011 versus 2.4-fold for the USA. The growth of Chinese meta-analyses was driven by genetics (110-fold increase in 2011 versus 2003). The HuGE Navigator identified 612 meta-analyses of genetic association studies published in 2012 from China versus only 109 from the USA. We compared in-depth 50 genetic association meta-analyses from China versus 50 from USA in 2012. Meta-analyses from China almost always used only literature-based data (92%), and focused on one or two genes (94%) and variants (78%) identified with candidate gene approaches (88%), while many USA meta-analyses used genome-wide approaches and raw data. Both groups usually concluded favorably for the presence of genetic associations (80% versus 74%), but nominal significance (P<0.05) typically sufficed in the China group. Meta-analyses from China typically neglected genome-wide data, and often included candidate gene studies published in Chinese-language journals. Overall, there is an impressive rise of meta-analyses from China, particularly on genetic associations. Since most claimed candidate gene associations are likely false-positives, there is an urgent global need to incorporate genome-wide data and state-of-the art statistical inferences to avoid a flood of false-positive genetic meta-analyses.


Assuntos
Bibliometria , Estudos de Associação Genética/estatística & dados numéricos , Metanálise como Assunto , PubMed/estatística & dados numéricos , China , Estudos de Associação Genética/história , História do Século XXI
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