| 1. |
- Qu, Yanhua, 1974-, et al.
(författare)
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Ground tit genome reveals avian adaptation to living at high altitudes in the Tibetan plateau.
- 2013
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Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 4, s. 2071-
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Tidskriftsartikel (refereegranskat)abstract
- The ground tit (Parus humilis) is endemic to the Tibetan plateau. It is a member of family Paridae but it was long thought to be related to the ground jays because of their morphological similarities. Here we present the ground tit's genome and re-sequence two tits and one ground jay, to clarify this controversially taxonomic status and uncover its genetic adaptations to the Tibetan plateau. Our results show that ground tit groups with two tits and it diverges from them between 7.7 and 9.9 Mya. Compared with other avian genomes, ground tit shows expansion in genes linked to energy metabolism and contractions in genes involved in immune and olfactory perception. We also found positively selected and rapidly evolving genes in hypoxia response and skeletal development. These results indicated that ground tit evolves basic strategies and 'tit-to-jay' change for coping with the life in an extreme environment.
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| 2. |
- Jung, Seungyoun, et al.
(författare)
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Alcohol consumption and breast cancer risk by estrogen receptor status : in a pooled analysis of 20 studies.
- 2016
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Ingår i: International Journal of Epidemiology. - : Oxford University Press (OUP). - 0300-5771 .- 1464-3685. ; 45:3, s. 916-928
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Breast cancer aetiology may differ by estrogen receptor (ER) status. Associations of alcohol and folate intakes with risk of breast cancer defined by ER status were examined in pooled analyses of the primary data from 20 cohorts.METHODS: During a maximum of 6-18 years of follow-up of 1 089 273 women, 21 624 ER+ and 5113 ER- breast cancers were identified. Study-specific multivariable relative risks (RRs) were calculated using Cox proportional hazards regression models and then combined using a random-effects model.RESULTS: Alcohol consumption was positively associated with risk of ER+ and ER- breast cancer. The pooled multivariable RRs (95% confidence intervals) comparing ≥ 30 g/d with 0 g/day of alcohol consumption were 1.35 (1.23-1.48) for ER+ and 1.28 (1.10-1.49) for ER- breast cancer (Ptrend ≤ 0.001; Pcommon-effects by ER status: 0.57). Associations were similar for alcohol intake from beer, wine and liquor. The associations with alcohol intake did not vary significantly by total (from foods and supplements) folate intake (Pinteraction ≥ 0.26). Dietary (from foods only) and total folate intakes were not associated with risk of overall, ER+ and ER- breast cancer; pooled multivariable RRs ranged from 0.98 to 1.02 comparing extreme quintiles. Following-up US studies through only the period before mandatory folic acid fortification did not change the results. The alcohol and folate associations did not vary by tumour subtypes defined by progesterone receptor status.CONCLUSIONS: Alcohol consumption was positively associated with risk of both ER+ and ER- breast cancer, even among women with high folate intake. Folate intake was not associated with breast cancer risk.
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| 3. |
- Jung, Seungyoun, et al.
(författare)
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Fruit and Vegetable Intake and Risk of Breast Cancer by Hormone Receptor Status
- 2013
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press (OUP): Policy B1. - 0027-8874 .- 1460-2105. ; 105:3, s. 219-236
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Tidskriftsartikel (refereegranskat)abstract
- Estrogen receptornegative (ER) breast cancer has few known or modifiable risk factors. Because ER tumors account for only 15% to 20% of breast cancers, large pooled analyses are necessary to evaluate precisely the suspected inverse association between fruit and vegetable intake and risk of ER breast cancer. less thanbrgreater than less thanbrgreater thanAmong 993 466 women followed for 11 to 20 years in 20 cohort studies, we documented 19 869 estrogen receptor positive (ER) and 4821 ER breast cancers. We calculated study-specific multivariable relative risks (RRs) and 95% confidence intervals (CIs) using Cox proportional hazards regression analyses and then combined them using a random-effects model. All statistical tests were two-sided. less thanbrgreater than less thanbrgreater thanTotal fruit and vegetable intake was statistically significantly inversely associated with risk of ER breast cancer but not with risk of breast cancer overall or of ER tumors. The inverse association for ER tumors was observed primarily for vegetable consumption. The pooled relative risks comparing the highest vs lowest quintile of total vegetable consumption were 0.82 (95% CI 0.74 to 0.90) for ER breast cancer and 1.04 (95% CI 0.97 to 1.11) for ER breast cancer (Pcommon-effects by ER status andlt; .001). Total fruit consumption was non-statistically significantly associated with risk of ER breast cancer (pooled multivariable RR comparing the highest vs lowest quintile 0.94, 95% CI 0.85 to 1.04). less thanbrgreater than less thanbrgreater thanWe observed no association between total fruit and vegetable intake and risk of overall breast cancer. However, vegetable consumption was inversely associated with risk of ER breast cancer in our large pooled analyses.
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| 4. |
- Zhang, Xuehong, et al.
(författare)
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Carotenoid intakes and risk of breast cancer defined by estrogen receptor and progesterone receptor status : a pooled analysis of 18 prospective cohort studies
- 2012
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Ingår i: American Journal of Clinical Nutrition. - : OXFORD UNIV PRESS. - 0002-9165 .- 1938-3207. ; 95:3, s. 713-725
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Tidskriftsartikel (refereegranskat)abstract
- Background: Epidemiologic studies examining associations between carotenoid intakes and risk of breast cancer by estrogen receptor (ER) and progesterone receptor (PR) status are limited. Objective: We investigated these associations in a pooled analysis of 18 cohort studies. Design: Of 1,028,438 participants followed for a maximum follow-up of 26 y across studies, 33,380 incident invasive breast cancers were identified. Study-specific RRs and 95% CIs were estimated by using Cox proportional hazards regression and then pooled by using a random-effects model. Results: alpha-Carotene, beta-carotene, and lutein/zeaxanthin intakes were inversely associated with the risk of ER-negative (ER-) breast cancer (pooled multivariable RRs of the comparison between the highest and lowest quintiles): alpha-carotene (0.87; 95% CI: 0.78, 0.97), beta-carotene (0.84; 95% CI: 0.77, 0.93), and lutein/zeaxanthin (0.87; 95% CI: 0.79, 0.95). These variables were not inversely associated with the risk of ER-positive (ER+) breast cancer (pooled multivariable RRs for the same comparison): a-carotene (1.04; 95% CI: 0.99, 1.09), beta-carotene (1.04; 95% CI: 0.98, 1.10), and lutein/zeaxanthin (1.00; 95% CI: 0.93, 1.07). Although the pooled RRs for quintile 5 for beta-cryptoxanthin were not significant, inverse trends were observed for ER- and ER+ breast cancer (P-trend <= 0.05). Nonsignificant associations were observed for lycopene intake. The associations were largely not appreciably modified by several breast cancer risk factors. Nonsignificant associations were observed for PR-positive and PR-negative breast cancer. Conclusions: Intakes of alpha-carotene, beta-carotene, and lutein/zeaxanthin were inversely associated with risk of ER-, but not ER+, breast cancer. However, the results need to be interpreted with caution because it is unclear whether the observed association is real or due to other constituents in the same food sources. Am J Clin Nutr 2012;95:713-25.
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| 5. |
- Zhang, Xuehong, et al.
(författare)
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Risk of Colon Cancer and Coffee, Tea, and Sugar-Sweetened Soft Drink Intake : Pooled Analysis of Prospective Cohort Studies
- 2010
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Ingår i: Journal of the National Cancer Institute. - : OXFORD UNIV PRESS INC. - 0027-8874 .- 1460-2105. ; 102:11, s. 771-783
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Tidskriftsartikel (refereegranskat)abstract
- The relationships between coffee, tea, and sugar-sweetened carbonated soft drink consumption and colon cancer risk remain unresolved. We investigated prospectively the association between coffee, tea, and sugar-sweetened carbonated soft drink consumption and colon cancer risk in a pooled analysis of primary data from 13 cohort studies. Among 731 441 participants followed for up to 6-20 years, 5604 incident colon cancer case patients were identified. Study-specific relative risks (RRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models and then pooled using a random-effects model. All statistical tests were two-sided. Compared with nonconsumers, the pooled multivariable relative risks were 1.07 (95% CI = 0.89 to 1.30, P-trend = .68) for coffee consumption greater than 1400 g/d (about six 8-oz cups) and 1.28 (95% CI = 1.02 to 1.61, P-trend = .01) for tea consumption greater than 900 g/d (about four 8-oz cups). For sugar-sweetened carbonated soft drink consumption, the pooled multivariable relative risk comparing consumption greater than 550 g/d (about 18 oz) to nonconsumers was 0.94 (95% CI = 0.66 to 1.32, P-trend = .91). No statistically significant between-studies heterogeneity was observed for the highest category of each beverage consumed (P > .20). The observed associations did not differ by sex, smoking status, alcohol consumption, body mass index, physical activity, or tumor site (P > .05). Drinking coffee or sugar-sweetened carbonated soft drinks was not associated with colon cancer risk. However, a modest positive association with higher tea consumption is possible and requires further study.
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| 6. |
- Fanidi, Anouar, et al.
(författare)
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Circulating Folate, Vitamin B6, and Methionine in Relation to Lung Cancer Risk in the Lung Cancer Cohort Consortium (LC3)
- 2018
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press. - 0027-8874 .- 1460-2105. ; 110:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Circulating concentrations of B vitamins and factors related to one-carbon metabolism have been found to be strongly inversely associated with lung cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. The extent to which these associations are present in other study populations is unknown.Methods: Within 20 prospective cohorts from the National Cancer Institute Cohort Consortium, a nested case-control study was designed including 5364 incident lung cancer case patients and 5364 control subjects who were individually matched to case patients by age, sex, cohort, and smoking status. Centralized biochemical analyses were performed to measure circulating concentrations of vitamin B6, folate, and methionine, as well as cotinine as an indicator of recent tobacco exposure. The association between these biomarkers and lung cancer risk was evaluated using conditional logistic regression models.Results: Participants with higher circulating concentrations of vitamin B6 and folate had a modestly decreased risk of lung cancer risk overall, the odds ratios when comparing the top and bottom fourths (OR 4vs1 ) being 0.88 (95% confidence interval [CI] = 0.78 to 1.00) and 0.86 (95% CI = 0.74 to 0.99), respectively. We found stronger associations among men (vitamin B6: OR 4vs1 = 0.74, 95% CI = 0.62 to 0.89; folate: OR 4vs1 = 0.75, 95% CI = 0.61 to 0.93) and ever smokers (vitamin B6: OR 4vs1 = 0.78, 95% CI = 0.67 to 0.91; folate: OR 4vs1 = 0.87, 95% CI = 0.73 to 1.03). We further noted that the association of folate was restricted to Europe/Australia and Asia, whereas no clear association was observed for the United States. Circulating concentrations of methionine were not associated with lung cancer risk overall or in important subgroups.Conclusions: Although confounding by tobacco exposure or reverse causation cannot be ruled out, these study results are compatible with a small decrease in lung cancer risk in ever smokers who avoid low concentrations of circulating folate and vitamin B6.
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| 7. |
- Fanidi, Anouar, et al.
(författare)
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Is high vitamin B12 status a cause of lung cancer?
- 2019
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Ingår i: International Journal of Cancer. - : John Wiley & Sons. - 0020-7136 .- 1097-0215. ; 145:6, s. 1499-1503
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Tidskriftsartikel (refereegranskat)abstract
- Vitamin B supplementation can have side effects for human health, including cancer risk. We aimed to elucidate the role of vitamin B12 in lung cancer etiology via direct measurements of pre‐diagnostic circulating vitamin B12 concentrations in a nested case–control study, complemented with a Mendelian randomization (MR) approach in an independent case–control sample. We used pre‐diagnostic biomarker data from 5183 case–control pairs nested within 20 prospective cohorts, and genetic data from 29,266 cases and 56,450 controls. Exposures included directly measured circulating vitamin B12 in pre‐diagnostic blood samples from the nested case–control study, and 8 single nucleotide polymorphisms associated with vitamin B12 concentrations in the MR study. Our main outcome of interest was increased risk for lung cancer, overall and by histological subtype, per increase in circulating vitamin B12 concentrations. We found circulating vitamin B12 to be positively associated with overall lung cancer risk in a dose response fashion (odds ratio for a doubling in B12 [ORlog2B12] = 1.15, 95% confidence interval (95%CI) = 1.06–1.25). The MR analysis based on 8 genetic variants also indicated that genetically determined higher vitamin B12 concentrations were positively associated with overall lung cancer risk (OR per 150 pmol/L standard deviation increase in B12 [ORSD] = 1.08, 95%CI = 1.00–1.16). Considering the consistency of these two independent and complementary analyses, these findings support the hypothesis that high vitamin B12 status increases the risk of lung cancer.
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| 8. |
- Feng, Xiaoshuang, et al.
(författare)
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Lung cancer risk discrimination of prediagnostic proteomics measurements compared with existing prediction tools
- 2023
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press. - 0027-8874 .- 1460-2105. ; 115:9, s. 1050-1059
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: We sought to develop a proteomics-based risk model for lung cancer and evaluate its risk-discriminatory performance in comparison with a smoking-based risk model (PLCOm2012) and a commercially available autoantibody biomarker test.METHODS: We designed a case-control study nested in 6 prospective cohorts, including 624 lung cancer participants who donated blood samples at most 3 years prior to lung cancer diagnosis and 624 smoking-matched cancer free participants who were assayed for 302 proteins. We used 470 case-control pairs from 4 cohorts to select proteins and train a protein-based risk model. We subsequently used 154 case-control pairs from 2 cohorts to compare the risk-discriminatory performance of the protein-based model with that of the Early Cancer Detection Test (EarlyCDT)-Lung and the PLCOm2012 model using receiver operating characteristics analysis and by estimating models' sensitivity. All tests were 2-sided.RESULTS: The area under the curve for the protein-based risk model in the validation sample was 0.75 (95% confidence interval [CI] = 0.70 to 0.81) compared with 0.64 (95% CI = 0.57 to 0.70) for the PLCOm2012 model (Pdifference = .001). The EarlyCDT-Lung had a sensitivity of 14% (95% CI = 8.2% to 19%) and a specificity of 86% (95% CI = 81% to 92%) for incident lung cancer. At the same specificity of 86%, the sensitivity for the protein-based risk model was estimated at 49% (95% CI = 41% to 57%) and 30% (95% CI = 23% to 37%) for the PLCOm2012 model.CONCLUSION: Circulating proteins showed promise in predicting incident lung cancer and outperformed a standard risk prediction model and the commercialized EarlyCDT-Lung.
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| 9. |
- Huang, Joyce Y., et al.
(författare)
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Circulating markers of cellular immune activation in prediagnostic blood sample and lung cancer risk in the Lung Cancer Cohort Consortium (LC3)
- 2020
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Ingår i: International Journal of Cancer. - : John Wiley & Sons. - 0020-7136 .- 1097-0215. ; 146:9, s. 2394-2405
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Tidskriftsartikel (refereegranskat)abstract
- Cell-mediated immune suppression may play an important role in lung carcinogenesis. We investigated the associations for circulating levels of tryptophan, kynurenine, kynurenine:tryptophan ratio (KTR), quinolinic acid (QA) and neopterin as markers of immune regulation and inflammation with lung cancer risk in 5,364 smoking-matched case-control pairs from 20 prospective cohorts included in the international Lung Cancer Cohort Consortium. All biomarkers were quantified by mass spectrometry-based methods in serum/plasma samples collected on average 6 years before lung cancer diagnosis. Odds ratios (ORs) and 95% confidence intervals (CIs) for lung cancer associated with individual biomarkers were calculated using conditional logistic regression with adjustment for circulating cotinine. Compared to the lowest quintile, the highest quintiles of kynurenine, KTR, QA and neopterin were associated with a 20-30% higher risk, and tryptophan with a 15% lower risk of lung cancer (all p(trend) < 0.05). The strongest associations were seen for current smokers, where the adjusted ORs (95% CIs) of lung cancer for the highest quintile of KTR, QA and neopterin were 1.42 (1.15-1.75), 1.42 (1.14-1.76) and 1.45 (1.13-1.86), respectively. A stronger association was also seen for KTR and QA with risk of lung squamous cell carcinoma followed by adenocarcinoma, and for lung cancer diagnosed within the first 2 years after blood draw. This study demonstrated that components of the tryptophan-kynurenine pathway with immunomodulatory effects are associated with risk of lung cancer overall, especially for current smokers. Further research is needed to evaluate the role of these biomarkers in lung carcinogenesis and progression.
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| 10. |
- Jackson, Sarah S., et al.
(författare)
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Anthropometric Risk Factors for Cancers of the Biliary Tract in the Biliary Tract Cancers Pooling Project
- 2019
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Ingår i: Cancer Research. - : AMER ASSOC CANCER RESEARCH. - 0008-5472 .- 1538-7445. ; 79:15, s. 3973-3982
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Tidskriftsartikel (refereegranskat)abstract
- Biliary tract cancers are rare but highly fatal with poorly understood etiology. Identifying potentially modifiable risk factors for these cancers is essential for prevention. Here we estimated the relationship between adiposity and cancer across the biliary tract, including cancers of the gallbladder (GBC), intrahepatic bile ducts (IHBDC), extrahepatic bile ducts (EHBDC), and the ampulla of Vater (AVC). We pooled data from 27 prospective cohorts with over 2.7 million adults. Adiposity was measured using baseline body mass index (BMI), waist circumference, hip circumference, waist-to-hip, and waist-to-height ratios. HRs and 95% confidence intervals (95% CI) were estimated using Cox proportional hazards models adjusted for sex, education, race, smoking, and alcohol consumption with age as the time metric and the baseline hazard stratified by study. During 37,883,648 person-years of follow-up, 1,343 GBC cases, 1,194 EHBDC cases, 784 IHBDC cases, and 623 AVC cases occurred. For each 5 kg/m(2) increase in BMI, there were risk increases for GBC (HR = 1.27; 95% CI, 1.19-1.36), IHBDC (HR = 1.32; 95% CI, 1.21-1.45), and EHBDC (HR = 1.13; 95% CI, 1.03-1.23), but not AVC (HR = 0.99; 95% CI, 0.88-1.11). Increasing waist circumference, hip circumference, waist-to-hip ratio, and waist-to-height ratio were associated with GBC and IHBDC but not EHBDC or AVC. These results indicate that adult adiposity is associated with an increased risk of biliary tract cancer, particularly GBC and IHBDC. Moreover, they provide evidence for recommending weight maintenance programs to reduce the risk of developing these cancers. Significance: These findings identify a correlation between adiposity and biliary tract cancers, indicating that weight management programs may help minimize the risk of these diseases.
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| 11. |
- Jasiunas, Rokas, et al.
(författare)
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From Generation to Extraction: A Time-Resolved Investigation of Photophysical Processes in Non-fullerene Organic Solar Cells
- 2020
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Ingår i: The Journal of Physical Chemistry C. - : AMER CHEMICAL SOC. - 1932-7447 .- 1932-7455. ; 124:39, s. 21283-21292
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Tidskriftsartikel (refereegranskat)abstract
- Non-fullerene organic solar cells (NFOSCs) demonstrate record efficiencies exceeding 16%. In comparison with cells with the fullerene-based acceptor, the NFOSCs benefit from a longer wavelength absorption, which leads to a small highest occupied molecular orbital (HOMO) level offset. Here, we use several advanced transient investigation techniques, covering timescale from sub-ps to mu s, to address all sequence of processes starting from photoexcitation of donors or acceptors to carrier extraction in several NFOSCs and cells with phenyl-C71-butyric acid methyl ester (PCBM). Though small offsets result in higher open-circuit voltage, we show that at the same time, it limits cell performance because of inefficient hole transfer from excited acceptors to donors and enhanced geminate recombination. We demonstrate that 100 meV HOMO level offset and proper acceptor molecule structures are sufficient for efficient hole transfer (>70%) and for reduction of the geminate recombination losses down to about 20%. Subsequent extraction of unbound charge carriers in all NFOSCs is slightly faster than in cells with PCBM, while non-geminate carrier recombination causing additional losses is slightly slower in the best performing NFOSCs than in cells with PCBM.
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| 12. |
- Kachuri, Linda, et al.
(författare)
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Fine mapping of chromosome 5p15.33 based on a targeted deep sequencing and high density genotyping identifies novel lung cancer susceptibility loci
- 2016
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Ingår i: Carcinogenesis. - : Oxford University Press (OUP). - 0143-3334 .- 1460-2180. ; 37:1, s. 96-105
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Tidskriftsartikel (refereegranskat)abstract
- Chromosome 5p15.33 has been identified as a lung cancer susceptibility locus, however the underlying causal mechanisms were not fully elucidated. Previous fine-mapping studies of this locus have relied on imputation or investigated a small number of known, common variants. This study represents a significant advance over previous research by investigating a large number of novel, rare variants, as well as their underlying mechanisms through telomere length. Variants for this fine-mapping study were identified through a targeted deep sequencing (average depth of coverage greater than 4000x) of 576 individuals. Subsequently, 4652 SNPs, including 1108 novel SNPs, were genotyped in 5164 cases and 5716 controls of European ancestry. After adjusting for known risk loci, rs2736100 and rs401681, we identified a new, independent lung cancer susceptibility variant in LPCAT1: rs139852726 (OR = 0.46, P = 4.73x10(-9)), and three new adenocarcinoma risk variants in TERT: rs61748181 (OR = 0.53, P = 2.64x10(-6)), rs112290073 (OR = 1.85, P = 1.27x10(-5)), rs138895564 (OR = 2.16, P = 2.06x10(-5); among young cases, OR = 3.77, P = 8.41x10(-4)). In addition, we found that rs139852726 (P = 1.44x10(-3)) was associated with telomere length in a sample of 922 healthy individuals. The gene-based SKAT-O analysis implicated TERT as the most relevant gene in the 5p15.33 region for adenocarcinoma (P = 7.84x10(-7)) and lung cancer (P = 2.37x10(-5)) risk. In this largest fine-mapping study to investigate a large number of rare and novel variants within 5p15.33, we identified novel lung and adenocarcinoma susceptibility loci with large effects and provided support for the role of telomere length as the potential underlying mechanism.
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| 13. |
- Larose, Tricia L., et al.
(författare)
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Circulating cotinine concentrations and lung cancer risk in the Lung Cancer Cohort Consortium (LC3)
- 2018
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Ingår i: International Journal of Epidemiology. - : Oxford University Press. - 0300-5771 .- 1464-3685. ; 47:6, s. 1760-1771
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Tidskriftsartikel (refereegranskat)abstract
- Background: Self-reported smoking is the principal measure used to assess lung cancer risk in epidemiological studies. We evaluated if circulating cotinine—a nicotine metabolite and biomarker of recent tobacco exposure—provides additional information on lung cancer risk.Methods: The study was conducted in the Lung Cancer Cohort Consortium (LC3) involving 20 prospective cohort studies. Pre-diagnostic serum cotinine concentrations were measured in one laboratory on 5364 lung cancer cases and 5364 individually matched controls. We used conditional logistic regression to evaluate the association between circulating cotinine and lung cancer, and assessed if cotinine provided additional risk-discriminative information compared with self-reported smoking (smoking status, smoking intensity, smoking duration), using receiver-operating characteristic (ROC) curve analysis.Results: We observed a strong positive association between cotinine and lung cancer risk for current smokers [odds ratio (OR ) per 500 nmol/L increase in cotinine (OR500): 1.39, 95% confidence interval (CI): 1.32–1.47]. Cotinine concentrations consistent with active smoking (≥115 nmol/L) were common in former smokers (cases: 14.6%; controls: 9.2%) and rare in never smokers (cases: 2.7%; controls: 0.8%). Former and never smokers with cotinine concentrations indicative of active smoking (≥115 nmol/L) also showed increased lung cancer risk. For current smokers, the risk-discriminative performance of cotinine combined with self-reported smoking (AUCintegrated: 0.69, 95% CI: 0.68–0.71) yielded a small improvement over self-reported smoking alone (AUCsmoke: 0.66, 95% CI: 0.64–0.68) (P = 1.5x10–9).Conclusions: Circulating cotinine concentrations are consistently associated with lung cancer risk for current smokers and provide additional risk-discriminative information compared with self-report smoking alone.
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| 14. |
- McGee, Emma E., et al.
(författare)
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Smoking, Alcohol, and Biliary Tract Cancer Risk : A Pooling Project of 26 Prospective Studies
- 2019
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Ingår i: Journal of the National Cancer Institute. - : OXFORD UNIV PRESS INC. - 0027-8874 .- 1460-2105. ; 111:12, s. 1263-1278
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Forskningsöversikt (refereegranskat)abstract
- Background: Tobacco and alcohol are well-established risk factors for numerous cancers, yet their relationship to biliary tract cancers remains unclear. Methods: We pooled data from 26 prospective studies to evaluate associations of cigarette smoking and alcohol consumption with biliary tract cancer risk. Study-specific hazard ratios (HRs) and 95% confidence intervals (CIs) for associations with smoking and alcohol consumption were calculated. Random-effects meta-analysis produced summary estimates. All statistical tests were two-sided. Results: Over a period of 38 369 156 person-years of follow-up, 1391 gallbladder, 758 intrahepatic bile duct, 1208 extrahepatic bile duct, and 623 ampulla of Vater cancer cases were identified. Ever, former, and current smoking were associated with increased extrahepatic bile duct and ampulla of Vater cancers risk (eg, current vs never smokers HR = 1.69, 95% CI = 1.34 to 2.13 and 2.22, 95% CI = 1.69 to 2.92, respectively), with dose-response effects for smoking pack-years, duration, and intensity (all P-trend<.01). Current smoking and smoking intensity were also associated with intrahepatic bile duct cancer (eg, >40 cigarettes per day vs never smokers HR = 2.15, 95 % CI = 1.15 to 4.00; P-trend = .001). No convincing association was observed between smoking and gallbladder cancer. Alcohol consumption was only associated with intrahepatic bile duct cancer, with increased risk for individuals consuming five or more vs zero drinks per day (HR = 2.35, 95%CI = 1.46 to 3.78; P-trend = .04). There was evidence of statistical heterogeneity among several cancer sites, particularly between gallbladder cancer and the other biliary tract cancers. Conclusions: Smoking appears to increase the risk of developing all biliary tract cancers except gallbladder cancer. Alcohol may increase the risk of intrahepatic bile duct cancer. Findings highlight etiologic heterogeneity across the biliary tract.
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| 15. |
- Midttun, Oivind, et al.
(författare)
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Circulating concentrations of biomarkers and metabolites related to vitamin status, one-carbon and the kynurenine pathways in US, Nordic, Asian, and Australian populations
- 2017
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Ingår i: American Journal of Clinical Nutrition. - : AMER SOC NUTRITION-ASN. - 0002-9165 .- 1938-3207. ; 105:6, s. 1314-1326
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Tidskriftsartikel (refereegranskat)abstract
- Background: Circulating concentrations of biomarkers that are related to vitamin status vary by factors such as diet, fortification, and supplement use. Published biomarker concentrations have also been influenced by the variation across laboratories, which complicates a comparison of results from different studies. Objective: We robustly and comprehensively assessed differences in biomarkers that are related to vitamin status across geographic regions. Design: The trial was a cross-sectional study in which we investigated 38 biomarkers that are related to vitamin status and one-carbon and tryptophan metabolism in serum and plasma from 5314 healthy control subjects representing 20 cohorts recruited from the United States, Nordic countries, Asia, and Australia, participating in the Lung Cancer Cohort Consortium. All samples were analyzed in a centralized laboratory. Results: Circulating concentrations of riboflavin, pyridoxal 5'-phosphate, folate, vitamin B-12, all-trans retinol, 25-hydroxyvitamin D, and a-tocopherol as well as combined vitamin scores that were based on these nutrients showed that the general B-vitamin concentration was highest in the United States and that the B vitamins and lipid soluble vitamins were low in Asians. Conversely, circulating concentrations of metabolites that are inversely related to B vitamins involved in the one-carbon and kynurenine pathways were high in Asians. The high B-vitamin concentration in the United States appears to be driven mainly by multivitamin-supplement users. Conclusions: The observed differences likely reflect the variation in intake of vitamins and, in particular, the widespread multivitamin-supplement use in the United States. The results provide valuable information about the differences in biomarker concentrations in populations across continents.
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| 16. |
- Midttun, Øivind, et al.
(författare)
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A cross-sectional study of inflammatory markers as determinants of circulating kynurenines in the Lung Cancer Cohort Consortium
- 2023
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Ingår i: Scientific Reports. - : Springer Nature. - 2045-2322. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- Circulating concentrations of metabolites (collectively called kynurenines) in the kynurenine pathway of tryptophan metabolism increase during inflammation, particularly in response to interferon-gamma (IFN-γ). Neopterin and the kynurenine/tryptophan ratio (KTR) are IFN-γ induced inflammatory markers, and together with C-reactive protein (CRP) and kynurenines they are associated with various diseases, but comprehensive data on the strength of associations of inflammatory markers with circulating concentrations of kynurenines are lacking. We measured circulating concentrations of neopterin, CRP, tryptophan and seven kynurenines in 5314 controls from 20 cohorts in the Lung Cancer Cohort Consortium (LC3). The associations of neopterin, KTR and CRP with kynurenines were investigated using regression models. In mixed models, one standard deviation (SD) higher KTR was associated with a 0.46 SD higher quinolinic acid (QA), and 0.31 SD higher 3-hydroxykynurenine (HK). One SD higher neopterin was associated with 0.48, 0.44, 0.36 and 0.28 SD higher KTR, QA, kynurenine and HK, respectively. KTR and neopterin respectively explained 24.1% and 16.7% of the variation in QA, and 11.4% and 7.5% of HK. CRP was only weakly associated with kynurenines in regression models. In summary, QA was the metabolite that was most strongly associated with the inflammatory markers. In general, the inflammatory markers were most strongly related to metabolites located along the tryptophan-NAD axis, which may support suggestions of increased production of NAD from tryptophan during inflammation.
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| 17. |
- Muller, David C., et al.
(författare)
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Circulating high sensitivity C reactive protein concentrations and risk of lung cancer : nested case-control study within Lung Cancer Cohort Consortium
- 2019
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Ingår i: The BMJ. - : BMJ Publishing Group Ltd. - 1756-1833 .- 0959-8138. ; 364
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Tidskriftsartikel (refereegranskat)abstract
- Objectives To conduct a comprehensive analysis of prospectively measured circulating high sensitivity C reactive protein (hsCRP) concentration and risk of lung cancer overall, by smoking status (never, former, and current smokers), and histological sub-type.Design Nested case-control study.Setting 20 population based cohort studies in Asia, Europe, Australia, and the United States.Participants 5299 patients with incident lung cancer, with individually incidence density matched controls.Exposure Circulating hsCRP concentrations in prediagnostic serum or plasma samples.Main outcome measure Incident lung cancer diagnosis.Results A positive association between circulating hsCRP concentration and the risk of lung cancer for current (odds ratio associated with a doubling in hsCRP concentration 1.09, 95% confidence interval 1.05 to 1.13) and former smokers (1.09, 1.04 to 1.14) was observed, but not for never smokers (P<0.01 for interaction). This association was strong and consistent across all histological subtypes, except for adenocarcinoma, which was not strongly associated with hsCRP concentration regardless of smoking status (odds ratio for adenocarcinoma overall 0.97, 95% confidence interval 0.94 to 1.01). The association between circulating hsCRP concentration and the risk of lung cancer was strongest in the first two years of follow-up for former and current smokers. Including hsCRP concentration in a risk model, in addition to smoking based variables, did not improve risk discrimination overall, but slightly improved discrimination for cancers diagnosed in the first two years of follow-up.Conclusions Former and current smokers with higher circulating hsCRP concentrations had a higher risk of lung cancer overall. Circulating hsCRP concentration was not associated with the risk of lung adenocarcinoma. Circulating hsCRP concentration could be a prediagnostic marker of lung cancer rather than a causal risk factor.
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| 18. |
- Robbins, Hilary A., et al.
(författare)
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Design and methodological considerations for biomarker discovery and validation in the Integrative Analysis of Lung Cancer Etiology and Risk (INTEGRAL) Program
- 2023
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Ingår i: Annals of Epidemiology. - : Elsevier. - 1047-2797 .- 1873-2585. ; 77, s. 1-12
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Tidskriftsartikel (refereegranskat)abstract
- The Integrative Analysis of Lung Cancer Etiology and Risk (INTEGRAL) program is an NCI-funded initiative with an objective to develop tools to optimize low-dose CT (LDCT) lung cancer screening. Here, we describe the rationale and design for the Risk Biomarker and Nodule Malignancy projects within INTEGRAL. The overarching goal of these projects is to systematically investigate circulating protein markers to include on a panel for use (i) pre-LDCT, to identify people likely to benefit from screening, and (ii) post-LDCT, to differentiate benign versus malignant nodules. To identify informative proteins, the Risk Biomarker project measured 1161 proteins in a nested-case control study within 2 prospective cohorts (n = 252 lung cancer cases and 252 controls) and replicated associations for a subset of proteins in 4 cohorts (n = 479 cases and 479 controls). Eligible participants had a current or former history of smoking and cases were diagnosed up to 3 years following blood draw. The Nodule Malignancy project measured 1078 proteins among participants with a heavy smoking history within four LDCT screening studies (n = 425 cases diagnosed up to 5 years following blood draw, 430 benign-nodule controls, and 398 nodule-free controls). The INTEGRAL panel will enable absolute quantification of 21 proteins. We will evaluate its performance in the Risk Biomarker project using a case-cohort study including 14 cohorts (n = 1696 cases and 2926 subcohort representatives), and in the Nodule Malignancy project within five LDCT screening studies (n = 675 cases, 680 benign-nodule controls, and 648 nodule-free controls). Future progress to advance lung cancer early detection biomarkers will require carefully designed validation, translational, and comparative studies.
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| 19. |
- Seyed Khoei, Nazlisadat, et al.
(författare)
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Circulating bilirubin levels and risk of colorectal cancer : serological and Mendelian randomization analyses
- 2020
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Ingår i: BMC Medicine. - : Springer Nature. - 1741-7015. ; 18:1
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Bilirubin, a byproduct of hemoglobin breakdown and purported anti-oxidant, is thought to be cancer preventive. We conducted complementary serological and Mendelian randomization (MR) analyses to investigate whether alterations in circulating levels of bilirubin are associated with risk of colorectal cancer (CRC). We decided a priori to perform analyses separately in men and women based on suggestive evidence that associations may differ by sex.METHODS: In a case-control study nested in the European Prospective Investigation into Cancer and Nutrition (EPIC), pre-diagnostic unconjugated bilirubin (UCB, the main component of total bilirubin) concentrations were measured by high-performance liquid chromatography in plasma samples of 1386 CRC cases and their individually matched controls. Additionally, 115 single-nucleotide polymorphisms (SNPs) robustly associated (P < 5 × 10-8) with circulating total bilirubin were instrumented in a 2-sample MR to test for a potential causal effect of bilirubin on CRC risk in 52,775 CRC cases and 45,940 matched controls in the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), the Colon Cancer Family Registry (CCFR), and the Colorectal Transdisciplinary (CORECT) study.RESULTS: The associations between circulating UCB levels and CRC risk differed by sex (Pheterogeneity = 0.008). Among men, higher levels of UCB were positively associated with CRC risk (odds ratio [OR] = 1.19, 95% confidence interval [CI] = 1.04-1.36; per 1-SD increment of log-UCB). In women, an inverse association was observed (OR = 0.86 (0.76-0.97)). In the MR analysis of the main UGT1A1 SNP (rs6431625), genetically predicted higher levels of total bilirubin were associated with a 7% increase in CRC risk in men (OR = 1.07 (1.02-1.12); P = 0.006; per 1-SD increment of total bilirubin), while there was no association in women (OR = 1.01 (0.96-1.06); P = 0.73). Raised bilirubin levels, predicted by instrumental variables excluding rs6431625, were suggestive of an inverse association with CRC in men, but not in women. These differences by sex did not reach formal statistical significance (Pheterogeneity ≥ 0.2).CONCLUSIONS: Additional insight into the relationship between circulating bilirubin and CRC is needed in order to conclude on a potential causal role of bilirubin in CRC development.
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| 20. |
- Simon, Tracey G., et al.
(författare)
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Association Between Aspirin Use and Risk of Hepatocellular Carcinoma
- 2018
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Ingår i: JAMA Oncology. - : American Medical Association. - 2374-2437 .- 2374-2445. ; 4:12, s. 1683-1690
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Tidskriftsartikel (refereegranskat)abstract
- IMPORTANCE: Prospective data on the risk of hepatocellular carcinoma (HCC) according to dose and duration of aspirin therapy are limited.OBJECTIVE: To examine the potential benefits of aspirin use for primary HCC prevention at a range of doses and durations of use within 2 prospective, nationwide populations.DESIGN, SETTING, AND PARTICIPANTS: Pooled analysis of 2 prospective US cohort studies: the Nurses' Health Study and the Health Professionals Follow-up Study. Data were accessed from November 1, 2017, through March 7, 2018. A total of 133 371 health care professionals who reported data on aspirin use, frequency, dosage, and duration of use biennially since 1980 in women and 1986 in men were included. Individuals with a cancer diagnosis at baseline (except nonmelanoma skin cancer) were excluded.MAIN OUTCOMES AND MEASURES: Cox proportional hazards regression modelswere used to calculate multivariable adjusted hazard ratios (HRs) and 95% CIs for HCC.RESULTS: Of the 133 371 participants, 87 507 were women and 45 864 were men; in 1996, the median time of follow-up, the mean (SD) age was 62 (8) years for women and 64 (8) years for men. Over more than 26 years of follow-up encompassing 4 232 188 person-years, 108 incident HCC cases (65 women, 43 men) were documented. Compared with nonregular use, regular aspirin use (>= 2 standard-dose [325-mg] tablets per week) was associated with reduced HCC risk (adjusted HR, 0.51; 95% CI, 0.34-0.77). This benefit appeared to be dose related: compared with nonuse, the multivariable-adjusted HR for HCC was 0.87 (95% CI, 0.51-1.48) for up to 1.5 standard-dose tablets per week, 0.51 (95% CI, 0.30-0.86) for more than 1.5 to 5 tablets per week, and 0.49 (95% CI, 0.28-0.96) for more than 5 tablets per week (P for trend =.006). Significantly lower HCC risk was observed with increasing duration (P for trend =.03); this decrease was apparent with use of 1.5 or more standard-dose aspirin tablets per week for 5 or more years (adjusted HR, 0.41; 95% CI, 0.21-0.77). In contrast, use of nonaspirin nonsteroidal anti-inflammatory drugs was not significantly associated with HCC risk (adjusted HR, 1.09; 95% CI, 0.78-1.51). CONCLUSIONS AND RELEVANCE: This study suggests that regular, long-term aspirin use is associated with a dose-dependent reduction in HCC risk, which is apparent after 5 or more years of use. Similar associations were not found with nonaspirin NSAIDs. Further research appears to be needed to clarify whether aspirin use represents a feasible strategy for primary prevention against HCC.
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| 21. |
- Theofylaktopoulou, Despoina, et al.
(författare)
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Impaired functional vitamin B6 status is associated with increased risk of lung cancer
- 2018
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 142:12, s. 2425-2434
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Tidskriftsartikel (refereegranskat)abstract
- Circulating vitamin B6 levels have been found to be inversely associated with lung cancer. Most studies have focused on the B6 form pyridoxal 5'-phosphate (PLP), a direct biomarker influenced by inflammation and other factors. Using a functional B6 marker allows further investigation of the potential role of vitamin B6 status in the pathogenesis of lung cancer. We prospectively evaluated the association of the functional marker of vitamin B6 status, the 3-hydroxykynurenine:xanthurenic acid (HK:XA) ratio, with risk of lung cancer in a nested case-control study consisting of 5,364 matched case-control pairs from the Lung Cancer Cohort Consortium (LC3). We used conditional logistic regression to evaluate the association between HK:XA and lung cancer, and random effect models to combine results from different cohorts and regions. High levels of HK:XA, indicating impaired functional B6 status, were associated with an increased risk of lung cancer, the odds ratio comparing the fourth and the first quartiles (OR4th vs. 1st) was 1.25 (95% confidence interval, 1.10-1.41). Stratified analyses indicated that this association was primarily driven by cases diagnosed with squamous cell carcinoma. Notably, the risk associated with HK:XA was approximately 50% higher in groups with a high relative frequency of squamous cell carcinoma, i.e., men, former and current smokers. This risk of squamous cell carcinoma was present in both men and women regardless of smoking status.
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| 22. |
- Yang, Jae Jeong, et al.
(författare)
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Association of Dietary Fiber and Yogurt Consumption With Lung Cancer Risk : A Pooled Analysis
- 2020
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Ingår i: JAMA Oncology. - : American Medical Association. - 2374-2437 .- 2374-2445. ; 6:2
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Tidskriftsartikel (refereegranskat)abstract
- Importance: Dietary fiber (the main source of prebiotics) and yogurt (a probiotic food) confer various health benefits via modulating the gut microbiota and metabolic pathways. However, their associations with lung cancer risk have not been well investigated.Objective: To evaluate the individual and joint associations of dietary fiber and yogurt consumption with lung cancer risk and to assess the potential effect modification of the associations by lifestyle and other dietary factors.Design, Setting, and Participants: This pooled analysis included 10 prospective cohorts involving 1 445 850 adults from studies that were conducted in the United States, Europe, and Asia. Data analyses were performed between November 2017 and February 2019. Using harmonized individual participant data, hazard ratios and 95% confidence intervals for lung cancer risk associated with dietary fiber and yogurt intakes were estimated for each cohort by Cox regression and pooled using random-effects meta-analysis. Participants who had a history of cancer at enrollment or developed any cancer, died, or were lost to follow-up within 2 years after enrollment were excluded.Exposures: Dietary fiber intake and yogurt consumption measured by validated instruments.Main Outcomes and Measures: Incident lung cancer, subclassified by histologic type (eg, adenocarcinoma, squamous cell carcinoma, and small cell carcinoma).Results: The analytic sample included 627 988 men, with a mean (SD) age of 57.9 (9.0) years, and 817 862 women, with a mean (SD) age of 54.8 (9.7) years. During a median follow-up of 8.6 years, 18 822 incident lung cancer cases were documented. Both fiber and yogurt intakes were inversely associated with lung cancer risk after adjustment for status and pack-years of smoking and other lung cancer risk factors: hazard ratio, 0.83 (95% CI, 0.76-0.91) for the highest vs lowest quintile of fiber intake; and hazard ratio, 0.81 (95% CI, 0.76-0.87) for high vs no yogurt consumption. The fiber or yogurt associations with lung cancer were significant in never smokers and were consistently observed across sex, race/ethnicity, and tumor histologic type. When considered jointly, high yogurt consumption with the highest quintile of fiber intake showed more than 30% reduced risk of lung cancer than nonyogurt consumption with the lowest quintile of fiber intake (hazard ratio, 0.67 [95% CI, 0.61-0.73] in total study populations; hazard ratio 0.69 [95% CI, 0.54-0.89] in never smokers), suggesting potential synergism.Conclusions and Relevance: Dietary fiber and yogurt consumption was associated with reduced risk of lung cancer after adjusting for known risk factors and among never smokers. Our findings suggest a potential protective role of prebiotics and probiotics against lung carcinogenesis.
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| 23. |
- Yu, Danxia, et al.
(författare)
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Prediagnostic calcium intake and lung cancer survival : A pooled analysis of 12 cohort studies
- 2017
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Ingår i: Cancer Epidemiology Biomarkers and Prevention. - 1055-9965. ; 26:7, s. 1060-1070
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Tidskriftsartikel (refereegranskat)abstract
- Background: Lung cancer is the leading cause of cancer death. Little is known about whether prediagnostic nutritional factors may affect survival. We examined the associations of prediagnostic calcium intake from foods and/or supplements with lung cancer survival. Methods: The present analysis included 23,882 incident, primary lung cancer patients from 12 prospective cohort studies. Dietary calcium intake was assessed using food-frequency questionnaires at baseline in each cohort and standardized to caloric intake of 2,000 kcal/d for women and 2,500 kcal/d for men. Stratified, multivariable-adjusted Cox regression was applied to compute hazard ratios (HR) and 95% confidence intervals (CI). Results: The 5-year survival rates were 56%, 21%, and 5.7% for localized, regional, and distant stage lung cancer, respectively. Low prediagnostic dietary calcium intake (<500-600 mg/d, less than half of the recommendation) was associated with a small increase in risk of death compared with recommended calcium intakes (800-1,200 mg/d); HR (95% CI) was 1.07 (1.01-1.13) after adjusting for age, stage, histology, grade, smoking status, pack-years, and other potential prognostic factors. The association between low calcium intake and higher lung cancer mortality was evident primarily among localized/regional stage patients, with HR (95% CI) of 1.15 (1.04-1.27). No association was found for supplemental calcium with survival in the multivariable-adjusted model. Conclusions: This large pooled analysis is the first, to our knowledge, to indicate that low prediagnostic dietary calcium intake may be associated with poorer survival among early-stage lung cancer patients. Impact: This multinational prospective study linked low calcium intake to lung cancer prognosis.
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| 24. |
- Zahed, Hana, et al.
(författare)
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Epidemiology of 40 blood biomarkers of one-carbon metabolism, vitamin status, inflammation, and renal and endothelial function among cancer-free older adults
- 2021
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Ingår i: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- Imbalances of blood biomarkers are associated with disease, and biomarkers may also vary non-pathologically across population groups. We described variation in concentrations of biomarkers of one-carbon metabolism, vitamin status, inflammation including tryptophan metabolism, and endothelial and renal function among cancer-free older adults. We analyzed 5167 cancer-free controls aged 40–80 years from 20 cohorts in the Lung Cancer Cohort Consortium (LC3). Centralized biochemical analyses of 40 biomarkers in plasma or serum were performed. We fit multivariable linear mixed effects models to quantify variation in standardized biomarker log-concentrations across four factors: age, sex, smoking status, and body mass index (BMI). Differences in most biomarkers across most factors were small, with 93% (186/200) of analyses showing an estimated difference lower than 0.25 standard-deviations, although most were statistically significant due to large sample size. The largest difference was for creatinine by sex, which was − 0.91 standard-deviations lower in women than men (95%CI − 0.98; − 0.84). The largest difference by age was for total cysteine (0.40 standard-deviation increase per 10-year increase, 95%CI 0.36; 0.43), and by BMI was for C-reactive protein (0.38 standard-deviation increase per 5-kg/m2 increase, 95%CI 0.34; 0.41). For 31 of 40 markers, the mean difference between current and never smokers was larger than between former and never smokers. A statistically significant (p < 0.05) association with time since smoking cessation was observed for 8 markers, including C-reactive protein, kynurenine, choline, and total homocysteine. We conclude that most blood biomarkers show small variations across demographic characteristics. Patterns by smoking status point to normalization of multiple physiological processes after smoking cessation.
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| 25. |
- Zhu, Youjian, et al.
(författare)
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Effect of sodium carboxymethyl cellulose addition on particulate matter emissions during biomass pellet combustion
- 2018
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Ingår i: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 230, s. 925-934
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Tidskriftsartikel (refereegranskat)abstract
- Sodium carboxymethyl cellulose (CMC) can be used as a cost-effective and environmentally friendly binder in the pelletizing process for production of biomass pellets with good quality. However, the effect of its addition on the emission of particulate matters (PM) during the combustion process, are still not clear. In this study, four typical biomass fuels, cotton stalk, cornstalk, camphorwood and rice husk, were used to investigate the effect of the addition of 5 wt% CMC in the biomass pellets on PM emissions during the combustion process. In the case of pure CMC combustion, a large amount of PM mainly with PM2.5 were generated, which was associated to the evaporation and condensation of NaOH and Na2CO3. The PM10 emission from the combustion of the four biomass fuels varied from 9.72 mg/Nm3 to 23.12 mg/Nm3 with mainly PM1. The addition of 5 wt% CMC in cotton stalk, corn stalk and camphorwood significantly increased the PM emissions due to the evaporation and subsequent condensation of Na-containing species, e.g. NaCl, Na2SO4, NaOH and Na2CO3. For rice husk, the addition of CMC hardly affected PM1 emission due to the dominated SiO2 component in rice husk ash, which reacted with the Na-containing species from the combustion of CMC and facilitated the formation of coarse ash particles and the reduction of PM1 emission. Although the addition of CMC in biomass fuels can greatly enhance the pellets qualities, its addition increases the PM emissions to varying degree. Therefore, in the industrial application of CMC to biomass densification, countermeasures such as mixing of high Si-containing rice husk or SiO2-rich minerals with biomass fuels should be taken to alleviate the PM issues resulting from the introduction of CMC.
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