| 1. |
- Aleksandrova, Krasimira, et al.
(author)
-
Adiposity, mediating biomarkers and risk of colon cancer in the European prospective investigation into cancer and nutrition study
- 2014
-
In: International Journal of Cancer. - : Wiley-Blackwell. - 0020-7136 .- 1097-0215. ; 134:3, s. 612-621
-
Journal article (peer-reviewed)abstract
- Adiposity is a risk factor for colon cancer, but underlying mechanisms are not well understood. We evaluated the extent to which 11 biomarkers with inflammatory and metabolic actions mediate the association of adiposity measures, waist circumference (WC) and body mass index (BMI), with colon cancer in men and women. We analyzed data from a prospective nested case-control study among 662 incident colon cancer cases matched within risk sets to 662 controls. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression. The percent effect change and corresponding CIs were estimated after adjusting for biomarkers shown to be associated with colon cancer risk. After multivariable adjustment, WC was associated with colon cancer risk in men (top vs. bottom tertile RR 1.68, 95% CI 1.06-2.65; ptrend = 0.02) and in women (RR 1.67, 95% CI 1.09-2.56; ptrend = 0.03). BMI was associated with risk only in men. The association of WC with colon cancer was accounted mostly for by three biomarkers, high-density lipoprotein cholesterol, non-high-molecular-weight adiponectin and soluble leptin receptor, which in combination explained 46% (95% CI 37-57%) of the association in men and 50% (95% CI 40-65%) of the association in women. Similar results were observed for the associations with BMI in men. These data suggest that alterations in levels of these metabolic biomarkers may represent a primary mechanism of action in the relation of adiposity with colon cancer. Further studies are warranted to determine whether altering their concentrations may reduce colon cancer risk.
|
|
| 2. |
- Aleksandrova, Krasimira, et al.
(author)
-
Total and high-molecular-weight adiponectin and risk of colorectal cancer : the European prospective investigation into cancer and nutrition study
- 2012
-
In: Carcinogenesis. - : Oxford University Press (OUP). - 0143-3334 .- 1460-2180. ; 33:6, s. 1211-1218
-
Journal article (peer-reviewed)abstract
- Adiponectin - an adipose-tissue-derived protein may provide a molecular link between obesity and colorectal cancer (CRC), but evidence from large prospective studies is limited. In particular, no epidemiological study explored high-molecular-weight (HMW) and non-HMW adiponectin fractions in relation to CRC risk, despite they were hypothesised to have differential biological activities, i.e. regulating insulin sensitivity (HMW-adiponectin) versus inflammatory response (non-HMW-adiponectin). In a prospective nested case-control study we investigated whether pre-diagnostic serum concentrations of total, HMW and non-HMW-adiponectin are associated with risk of CRC, independent of obesity and other known CRC risk factors. A total of 1206 incident cases (755 colon, 451 rectal) were matched to 1206 controls using incidence density sampling. In conditional logistic regression, adjusted for dietary and lifestyle factors, total adiponectin and non-HMW-adiponectin concentrations were inversely associated with risk of CRC [relative risk (RR) comparing highest versus lowest quintile = 0.71, 95% confidence interval (CI) = 0.53-0.95, P (trend)=0.03 for total adiponectin and 0.45, 95%CI=0.34-0.61, P (trend)<0.0001 for non-HMW-adiponectin]. HMW-adiponectin concentrations were not associated with CRC risk (RR=0.91, 95%CI=0.68-1.22, P (trend)=0.55). Non-HMW-adiponectin was associated with CRC risk even after adjustment for body mass index and waist circumference (RR=0.39, 95%CI=0.26-0.60, P (trend)<0.0001); whereas the association with total adiponectin was no longer significant (RR=0.81, 95%CI=0.60-1.09, P (trend)=0.23). When stratified by cancer site, non-HMW-adiponectin was inversely associated with both colon and rectal cancer. These findings suggest an important role of the relative proportion of non-HMW-adiponectin in CRC pathogenesis. Future studies are warranted to confirm these results and to elucidate the underlying mechanisms.
|
|
| 3. |
- Baltar, Valéria Troncoso, et al.
(author)
-
A structural equation modelling approach to explore the role of B vitamins and immune markers in lung cancer risk
- 2013
-
In: European Journal of Epidemiology. - : Springer Science and Business Media LLC. - 0393-2990 .- 1573-7284. ; 28:8, s. 677-688
-
Journal article (peer-reviewed)abstract
- The one-carbon metabolism (OCM) is considered key in maintaining DNA integrity and regulating gene expression, and may be involved in the process of carcinogenesis. Several B-vitamins and amino acids have been implicated in lung cancer risk, via the OCM directly as well as immune system activation. However it is unclear whether these factors act independently or through complex mechanisms. The current study applies structural equations modelling (SEM) to further disentangle the mechanisms involved in lung carcinogenesis. SEM allows simultaneous estimation of linear relations where a variable can be the outcome in one equation and the predictor in another, as well as allowing estimation using latent variables (factors estimated by correlation matrix). A large number of biomarkers have been analysed from 891 lung cancer cases and 1,747 controls nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Four putative mechanisms in the OCM and immunity were investigated in relation to lung cancer risk: methionine-homocysteine metabolism, folate cycle, transsulfuration, and mechanisms involved in inflammation and immune activation, all adjusted for tobacco exposure. The hypothesized SEM model confirmed a direct and protective effect for factors representing methionine-homocysteine metabolism (p = 0.020) and immune activation (p = 0.021), and an indirect protective effect of folate cycle (p = 0.019), after adjustment for tobacco smoking. In conclusion, our results show that in the investigation of the involvement of the OCM, the folate cycle and immune system in lung carcinogenesis, it is important to consider complex pathways (by applying SEM) rather than the effects of single vitamins or nutrients (e.g. using traditional multiple regression). In our study SEM were able to suggest a greater role of the methionine-homocysteine metabolism and immune activation over other potential mechanisms.
|
|
| 4. |
- Baltar, Valéria Troncoso, et al.
(author)
-
Smoking, secondhand smoke, and cotinine levels in a subset of EPIC cohort
- 2011
-
In: Cancer Epidemiology, Biomarkers and Prevention. - : American Association for Cancer Research. - 1055-9965 .- 1538-7755. ; 20:5, s. 869-875
-
Journal article (peer-reviewed)abstract
- Background: Several countries are discussing new legislation regarding the ban on smoking in public places, based on the growing evidence of the hazards of secondhand smoke (SHS) exposure. The objective of the present study is to quantitatively assess the relationship between smoking, SHS, and serum cotinine levels in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Methods: From a study on lung cancer in the EPIC cohort, questionnaire information on smoking was collected at enrolment, and cotinine was measured in serum. Three statistical models were applied by using samples available in a cross-section design: (i) cotinine levels by categories combining smoking and SHS (n = 859); (ii) the effect of hours of passive smoking exposure in nonsmokers only (n = 107); (iii) the effect of the number of cigarettes consumed per day in current smokers only (n = 832). All models were adjusted for country, sex, age, and body mass index. Results: Among nonsmokers, passive smokers presented significant differences in cotinine compared with nonexposed, with a marked (but not significant) difference among former-smokers. A one hour per day increment of SHS gave rise to a significant 2.58 nmol/L (0.45 ng/mL) increase in mean serum cotinine (P < 0.001). In current smokers, a one cigarette per day increment gave rise to a significant 22.44 nmol/L (3.95 ng/mL) increase in cotinine mean (P < 0.001). Conclusions: There is clear evidence that not only tobacco smoking but also involuntary exposure increases cotinine levels. Impact: This study strengthens the evidence for the benefits of a smoking ban in public places.
|
|
| 5. |
|
|
| 6. |
- Crowe, Francesca L, et al.
(author)
-
Fruit and vegetable intake and mortality from ischaemic heart disease : results from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Heart study.
- 2011
-
In: European Heart Journal. - : Oxford University Press (OUP). - 0195-668X .- 1522-9645. ; 32:10, s. 1235-1243
-
Journal article (peer-reviewed)abstract
- AIMS: A higher intake of fruits and vegetables has been associated with a lower risk of ischaemic heart disease (IHD), but there is some uncertainty about the interpretation of this association. The objective was to assess the relation between fruit and vegetable intake and risk of mortality from IHD in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Heart study. METHODS AND RESULTS: After an average of 8.4 years of follow-up, there were 1636 deaths from IHD among 313 074 men and women without previous myocardial infarction or stroke from eight European countries. Participants consuming at least eight portions (80 g each) of fruits and vegetables a day had a 22% lower risk of fatal IHD [relative risk (RR) = 0.78, 95% confidence interval (CI): 0.65-0.95] compared with those consuming fewer than three portions a day. After calibration of fruit and vegetable intake to account for differences in dietary assessment between the participating centres, a one portion (80 g) increment in fruit and vegetable intake was associated with a 4% lower risk of fatal IHD (RR = 0.96, 95% CI: 0.92-1.00, P for trend = 0.033). CONCLUSION: Results from this large observational study suggest that a higher intake of fruits and vegetables is associated with a reduced risk of IHD mortality. Whether this association is causal and, if so, the biological mechanism(s) by which fruits and vegetables operate to lower IHD risks remains unclear.
|
|
| 7. |
- Fedirko, Veronika, et al.
(author)
-
Prediagnostic 25-Hydroxyvitamin D, VDR and CASR polymorphisms, and survival in patients with colorectal cancer in Western European populations
- 2012
-
In: Cancer Epidemiology, Biomarkers and Prevention. - 1055-9965 .- 1538-7755. ; 21:4, s. 582-593
-
Journal article (peer-reviewed)abstract
- Background: Individuals with higher blood 25-hydroxyvitamin D [25(OH)D] levels have a lower risk of developing colorectal cancer (CRC), but the influence of 25(OH)D on mortality after CRC diagnosis is unknown.Methods: The association between prediagnostic 25(OH)D levels and CRC-specific (N ¼ 444) and overall mortality (N ¼ 541) was prospectively examined among 1,202 participants diagnosed with CRC between 1992 and 2003 in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort.Multivariable Cox proportional hazards models were used to calculate HRs and corresponding 95% CIs according to 25(OH)D quintiles and genetic variation within the VDR and CASR genes. Potential dietary, lifestyle, and metabolic effect modifiers were also investigated.Results: There were 541 deaths, 444 (82%) due to CRC. Mean follow-up was 73 months. In multivariable analysis, higher 25(OH)D levels were associated with a statistically significant reduction in CRC-specific (Ptrend ¼ 0.04) and overall mortality (Ptrend ¼ 0.01). Participants with 25(OH)D levels in the highest quintile had an adjusted HR of 0.69 (95% CI: 0.50–0.93) for CRC-specific mortality and 0.67 (95% CI: 0.50–0.88) for overall mortality, compared with the lowest quintile. Except for a possible interaction by prediagnostic dietary calcium intake (Pinteraction ¼ 0.01), no other potential modifying factors related to CRC survival were noted. The VDR (FokI and BsmI) and CASR (rs1801725) genotypes were not associated with survival.Conclusions: High prediagnostic 25(OH)D levels are associated with improved survival of patients with CRC. Impact: Our findings may stimulate further research directed at investigating the effects of blood vitamin D levels before, at, and after CRC diagnosis on outcomes in CRC patients.
|
|
| 8. |
- Grote, Verena A., et al.
(author)
-
The association of circulating adiponectin levels with pancreatic cancer risk: A study within the prospective EPIC cohort
- 2012
-
In: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 130, s. 2428-2437
-
Journal article (peer-reviewed)abstract
- Excess body weight and type 2 diabetes mellitus, risk factors of pancreatic cancer, are characterized by decreased levels of adiponectin. In addition to anti-inflammatory and anti-proliferative actions, adiponectin has an important role in regulating glucose metabolism, i.e., decreasing circulating blood glucose levels. Prospectively, hyperglycemia has been associated with risk of pancreatic cancer. The aim of this study was to investigate the association of pre-diagnostic adiponectin levels with pancreatic cancer risk. We conducted a case-control study nested within European Prospective Investigation into Cancer and Nutrition. Blood samples of 452 pancreatic cancer cases and 452 individually matched controls were analyzed by immunoassays. Multivariate conditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI). Overall, adiponectin showed no association with pancreas cancer risk; however, among never smokers, higher circulating levels of adiponectin were associated with a reduction in pancreatic cancer risk (OR = 0.44 [95% CI 0.23-0.82] for highest vs. lowest quartile), whereas among current smokers there was no significant association (OR = 1.59 [95% CI 0.67-3.76] for highest vs. lowest quartile; p-trend = 0.530; p-interaction = 0.309). In our study, lower adiponectin concentrations may be associated with the development of pancreatic cancer among never smokers, whereas the only other prospective study being conducted so far showed a decrease in risk among male smokers. Therefore, further studies are needed to clarify the role of adiponectin in pancreatic cancer development. © 2011 UICC.
|
|
| 9. |
|
|
| 10. |
- Leufkens, Anke M, et al.
(author)
-
Biomarkers of oxidative stress and risk of developing colorectal cancer : a cohort-nested case-control study in the European Prospective Investigation into Cancer and Nutrition
- 2012
-
In: American Journal of Epidemiology. - : Oxford University Press (OUP). - 0002-9262 .- 1476-6256. ; 175:7, s. 653-663
-
Journal article (peer-reviewed)abstract
- Oxidative stress has been shown to play an important role in carcinogenesis, but prospective evidence for an association between biomarkers of oxidative stress and colorectal cancer (CRC) risk is limited. The authors investigated the association between prediagnostic serum levels of oxidative stress indicators (i.e., reactive oxygen metabolites (ROM) and ferric reducing ability of plasma (FRAP)) and CRC risk. This was examined in a nested case-control study (1,064 CRC cases, 1,064 matched controls) in the European Prospective Investigation Into Cancer and Nutrition cohort (1992-2003). Incidence rate ratios and 95% confidence intervals were calculated using conditional logistic regression analyses. ROM were associated with overall CRC risk (highest tertile vs. lowest: adjusted incidence rate ratio (IRR(adj)) = 1.91, 95% confidence interval (CI): 1.47, 2.48), proximal (IRR(adj) = 1.89, 95% CI: 1.06, 3.36) and distal (IRR(adj) = 2.31, 95% CI: 1.37, 3.89) colon cancer, and rectal cancer (IRR(adj) = 1.69, 95% CI: 1.05, 2.72). When results were stratified by tertile of follow-up time, the association remained significant only in participants with less than 2.63 years of follow-up (IRR(adj) = 2.28, 95% CI: 1.78, 2.94; P-heterogeneity < 0.01). FRAP was not associated with CRC risk. In conclusion, prediagnostic serum ROM levels were associated with increased risk of CRC. However, this association was seen only in subjects with relatively short follow-up, suggesting that the association results from production of reactive oxygen species by preclinical tumors.
|
|
