Sara Regnér

Hepatocellular Carcinoma Risk Factors and Disease Burden in a European Cohort: A Nested Case–Control Study

BACKGROUND To date, no attempt has been made to systematically determine the apportionment of the hepatocellular carcinoma burden in Europe or North America among established risk factors. METHODS Using data collected from 1992 to 2006, which included 4,409,809 person-years in the European Prospective Investigation into Cancer and nutrition (EPIC), we identified 125 case patients with hepatocellular carcinoma, of whom 115 were matched to 229 control subjects. We calculated odds ratios (ORs) for the association of documented risk factors for hepatocellular carcinoma with incidence of this disease and estimated their importance in this European cohort. RESULTS Chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infection (OR = 9.10, 95% confidence interval [CI] = 2.10 to 39.50 and OR = 13.36, 95% CI = 4.11 to 43.45, respectively), obesity (OR = 2.13, 95% CI = 1.06 to 4.29), former or current smoking (OR = 1.98, 95% CI = 0.90 to 4.39 and OR = 4.55, 95% CI = 1.90 to 10.91, respectively), and heavy alcohol intake (OR = 1.77, 95% CI = 0.73 to 4.27) were associated with hepatocellular carcinoma. Smoking contributed to almost half of all hepatocellular carcinomas (47.6%), whereas 13.2% and 20.9% were attributable to chronic HBV and HCV infection, respectively. Obesity and heavy alcohol intake contributed 16.1% and 10.2%, respectively. Almost two-thirds (65.7%, 95% CI = 50.6% to 79.3%) of hepatocellular carcinomas can be accounted for by exposure to at least one of these documented risk factors. CONCLUSIONS Smoking contributed to more hepatocellular carcinomas in this Europe-wide cohort than chronic HBV and HCV infections. Heavy alcohol consumption and obesity also contributed to sizeable fractions of this disease burden. These contributions may be underestimates because EPIC volunteers are likely to be more health conscious than the general population.

Adherence to a Mediterranean diet and risk of gastric adenocarcinoma within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort study

BACKGROUND The Mediterranean dietary pattern is believed to protect against cancer, although evidence from cohort studies that have examined particular cancer sites is limited. OBJECTIVE We aimed to explore the association between adherence to a relative Mediterranean diet (rMED) and incident gastric adenocarcinoma (GC) within the European Prospective Investigation into Cancer and Nutrition study. DESIGN The study included 485,044 subjects (144,577 men) aged 35-70 y from 10 European countries. At recruitment, dietary and lifestyle information was collected. An 18-unit rMED score, incorporating 9 key components of the Mediterranean diet, was used to estimate rMED adherence. The association between rMED and GC with respect to anatomic location (cardia and noncardia) and histologic types (diffuse and intestinal) was investigated. A calibration study in a subsample was used to control for dietary measurement error. RESULTS After a mean follow-up of 8.9 y, 449 validated incident GC cases were identified and used in the analysis. After stratification by center and age and adjustment for recognized cancer risk factors, high compared with low rMED adherence was associated with a significant reduction in GC risk (hazard ratio: 0.67; 95% CI: 0.47, 0.94). A 1-unit increase in the rMED score was associated with a decreased risk of GC of 5% (95% CI: 0.91, 0.99). There was no evidence of heterogeneity between different anatomic locations or histologic types. The calibrated results showed similar trends (overall hazard ratio for GC: 0.93; 95% CI: 0.89, 0.99). CONCLUSION Greater adherence to an rMED is associated with a significant reduction in the risk of incident GC.

IL-6 trans-signaling promotes pancreatitis-associated lung injury and lethality

Acute lung injury (ALI) is an inflammatory disease with a high mortality rate. Although typically seen in individuals with sepsis, ALI is also a major complication in severe acute pancreatitis (SAP). The pathophysiology of SAP-associated ALI is poorly understood, but elevated serum levels of IL-6 is a reliable marker for disease severity. Here, we used a mouse model of acute pancreatitis-associated (AP-associated) ALI to determine the role of IL-6 in ALI lethality. Il6-deficient mice had a lower death rate compared with wild-type mice with AP, while mice injected with IL-6 were more likely to develop lethal ALI. We found that inflammation-associated NF-κB induced myeloid cell secretion of IL-6, and the effects of secreted IL-6 were mediated by complexation with soluble IL-6 receptor, a process known as trans-signaling. IL-6 trans-signaling stimulated phosphorylation of STAT3 and production of the neutrophil attractant CXCL1 in pancreatic acinar cells. Examination of human samples revealed expression of IL-6 in combination with soluble IL-6 receptor was a reliable predictor of ALI in SAP. These results demonstrate that IL-6 trans-signaling is an essential mediator of ALI in SAP across species and suggest that therapeutic inhibition of IL-6 may prevent SAP-associated ALI.

Abdominal obesity, weight gain during adulthood and risk of liver and biliary tract cancer in a European cohort

General obesity has been positively associated with risk of liver and probably with biliary tract cancer, but little is known about abdominal obesity or weight gain during adulthood. We used multivariable Cox proportional hazard models to investigate associations between weight, body mass index, waist and hip circumference, waist‐to‐hip and waist‐to‐height ratio (WHtR), weight change during adulthood and risk of hepatocellular carcinoma (HCC), intrahepatic (IBDC) and extrahepatic bile duct system cancer [EBDSC including gallbladder cancer (GBC)] among 359,525 men and women in the European Prospective Investigation into Cancer and Nutrition study. Hepatitis B and C virus status was measured in a nested case–control subset. During a mean follow‐up of 8.6 years, 177 cases of HCC, 58 cases of IBDC and 210 cases of EBDSC, including 76 cases of GBC, occurred. All anthropometric measures were positively associated with risk of HCC and GBC. WHtR showed the strongest association with HCC [relative risk (RR) comparing extreme tertiles 3.51, 95% confidence interval (95% CI): 2.09–5.87; ptrend < 0.0001] and with GBC (RR: 1.56, 95% CI: 1.12–2.16 for an increment of one unit in WHtR). Weight gain during adulthood was also positively associated with HCC when comparing extreme tertiles (RR: 2.48, 95% CI: 1.49–4.13; <0.001). No statistically significant association was observed between obesity and risk of IBDC and EBDSC. Our results provide evidence of an association between obesity, particularly abdominal obesity, and risk of HCC and GBC. Our findings support public health recommendations to reduce the prevalence of obesity and weight gain in adulthood for HCC and GBC prevention in Western populations.

Fruit and vegetable intake and the risk of gastric adenocarcinoma: a reanalysis of the European Prospective Investigation into Cancer and Nutrition (EPIC-EURGAST) study after a longer follow-up.

In a previous European prospective investigation into cancer and nutrition (EPIC) analysis, we found an inverse association between total intake of vegetables, onion and garlic, and risk of intestinal gastric cancer (GC) and between citrus fruit and risk of cardia GC. The aim of this study is to reanalyze the effect of fruit and vegetables (F&V), based on a longer follow‐up and twice the number of GC cases. Subjects are 477,312 men and women mostly aged 35 to 70 years participating in the EPIC cohort, including 683 gastric adenocarcinomas with 11 years of follow‐up. Information on diet and lifestyle was collected at baseline. A calibration study in a subsample was used to correct for dietary measurement errors. When comparing the highest vs. lowest quintile of intake, we found an inverse association between total intake of V&F and GC risk [hazard ratio (HR) 0.77; 95% confidence interval (CI) 0.57–1.04; p for trend 0.02], between fresh fruit and risk of the diffuse type (HR 0.59; 95% CI 0.36–0.97; p for trend 0.03) and an inverse association between citrus fruit and risk of cardia cancer (HR 0.61; 95% CI 0.38–1.00, p for trend 0.01). Although calibration revealed somewhat stronger inverse associations, none of the risks reached statistical significance. There was no association between total or specific vegetables intake and GC risk. The inverse association between fresh fruit and citrus fruits and risk of GC seems to be restricted to smokers and the Northern European countries. Fresh fruit and citrus fruit consumption may protect against diffuse and cardia GC, respectively.

Aberrant DNA methylation of cancer-associated genes in gastric cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC–EURGAST)

Epigenetic events have emerged as key mechanisms in the regulation of critical biological processes and in the development of a wide variety of human malignancies, including gastric cancer (GC), however precise gene targets of aberrant DNA methylation in GC remain largely unknown. Here, we have combined pyrosequencing-based quantitative analysis of DNA methylation in 98 GC cases and 64 controls nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort and in cancer tissue and non-tumorigenic adjacent tissue of an independent series of GC samples. A panel of 10 cancer-associated genes (CHRNA3, DOK1, MGMT, RASSF1A, p14ARF, CDH1, MLH1, ALDH2, GNMT and MTHFR) and LINE-1 repetitive elements were included in the analysis and their association with clinicopathological characteristics (sex, age at diagnosis, anatomical sub-site, histological sub-type) was examined. Three out of the 10 genes analyzed exhibited a marked hypermethylation, whereas two genes (ALDH2 and MTHFR) showed significant hypomethylation, in gastric tumors. Among differentially methylated genes, we identified new genes (CHRNA3 and DOK1) as targets of aberrant hypermethylation in GC, suggesting that epigenetic deregulation of these genes and their corresponding cellular pathways may promote the development and progression of GC. We also found that global demethylation of tumor cell genomes occurs in GC, consistent with the notion that abnormal hypermethylation of specific genes occurs concomitantly with genome-wide hypomethylation. Age and gender had no significant influence on methylation states, but an association was observed between LINE-1 and MLH1 methylation levels with histological sub-type and anatomical sub-site. This study identifies aberrant methylation patters in specific genes in GC thus providing information that could be exploited as novel biomarkers in clinics and molecular epidemiology of GC.

Role of neutrophils in the activation of trypsinogen in severe acute pancreatitis

The relationship between inflammation and proteolytic activation in pancreatitis is an unresolved issue in pancreatology. The purpose of this study was to define the influence of neutrophils on trypsinogen activation in severe AP. Pancreatitis was induced by infusion of taurocholate into the pancreatic duct in C57BL/6 mice. For neutrophil depletion, an anti‐Gr‐1 antibody was administered before pancreatitis induction. Administration of the anti‐Gr‐1 antibody reduced circulating neutrophils by 97%. Pancreatic TAP and serum amylase levels increased 2 h and 24 h after induction of pancreatitis. Neutrophil depletion reduced pancreatic TAP and serum amylase levels at 24 h but not at 2 h after pancreatitis induction. Pancreatic MPO and infiltration of neutrophils, as well as MIP‐2 levels, were increased 24 h after taurocholate infusion. Two hours after taurocholate administration, no significant pancreatic infiltration of neutrophils was observed. Injection of the anti‐Gr‐1 antibody abolished MPO activity, neutrophil accumulation, and MIP‐2 levels, as well as acinar cell necrosis, hemorrhage, and edema in the pancreas at 24 h. Moreover, taurocholate‐provoked tissue damage and MPO activity in the lung were normalized by neutrophil depletion. Intravital fluorescence microscopy revealed a 97% reduction of leukocytes in the pancreatic microcirculation after administration of the anti‐Gr‐1 antibody. Our data demonstrate that initial trypsinogen activation is independent of neutrophils, whereas later activation is dependent on neutrophils in the pancreas. Neutrophils are critical in mediating pancreatic and lung tissue damage in severe AP.

Infection with Hepatitis B and C Viruses and Risk of Lymphoid Malignancies in the European Prospective Investigation into Cancer and Nutrition (EPIC)

Background: Case–control studies suggested a moderate, but consistent, association of hepatitis C virus (HCV) infection with lymphoid tissue malignancies, especially non–Hodgkin lymphoma (NHL). More limited data suggested that hepatitis B virus (HBV) infection might also be associated with NHL. However, prospective studies on the topic are few. Methods: A nested case–control study was conducted in eight countries participating in the EPIC prospective study. Seven hundred thirty-nine incident cases of NHL, 238 multiple myeloma (MM), and 46 Hodgkin lymphoma (HL) were matched with 2,028 controls. Seropositivity to anti-HCV, anti-HBc, and HBsAg was evaluated and conditional logistic regression was used to estimate odds ratios (OR) and corresponding 95% confidence intervals (CI) for NHL, MM, or HL, and their combination. Results: Anti-HCV seropositivity among controls in different countries ranged from 0% to 5.3%; HBsAg from 0% to 2.7%; and anti-HBc from 1.9% to 45.9%. Similar nonsignificant associations were found with seropositivity to HBsAg for NHL (OR = 1.78; 95% CI: 0.78–4.04), MM (OR = 4.00; 95% CI: 1.00–16.0), and HL (OR = 2.00; 95% CI: 0.13–32.0). The association between HBsAg and the combination of NHL, MM, and HL (OR = 2.21; 95% CI: 1.12–4.33) was similar for cancer diagnosed less than 3 and 3 or more years after blood collection. No significant association was found between anti-HCV and NHL, MM, or HL risk, but the corresponding CIs were very broad. Conclusions: Chronic HBV infection may increase the risk of lymphoid malignancies among healthy European volunteers. Impact: Treatment directed at control of HBV infection should be evaluated in HBsAg-seropositive patients with lymphoid tissue malignancies. Cancer Epidemiol Biomarkers Prev; 20(1); 208–14. ©2011 AACR.

Dietary total antioxidant capacity and gastric cancer risk in the European prospective investigation into cancer and nutrition study

A high intake of dietary antioxidant compounds has been hypothesized to be an appropriate strategy to reduce gastric cancer (GC) development. We investigated the effect of dietary total antioxidant capacity (TAC) in relation to GC in the European Prospective Investigation into Cancer (EPIC) study including 23 centers in 10 European countries. A total of 521,457 subjects (153,447 men) aged mostly 35–70 years old, were recruited largely between 1992 and 1998. Ferric reducing antioxidant potential (FRAP) and total radical‐trapping antioxidant parameter (TRAP), measuring reducing and chain‐breaking antioxidant capacity were used to measure dietary TAC from plant foods. Dietary antioxidant intake is associated with a reduction in the risk of GC for both FRAP (adjusted HR 0.66; 95%CI (0.46–0.95) and TRAP (adjusted HR 0.61; 95%CI (0.43–0.87) (highest vs. lowest quintile). The association was observed for both cardia and noncardia cancers. A clear effect was observed in smokers with a significant reduction in GC risk for the fifth quintile of intake for both assays (highest vs. lowest quintile: adjusted HR 0.41; 95%CI (0.22–0.76) p for trend <0.001 for FRAP; adjusted HR 0.52; 95%CI (0.28–0.97) p for trend <0.001 for TRAP) but not in nonsmokers. In former smokers, the association with FRAP intake was statistically significant (highest vs. lowest quintile: adjusted HR 0.4; 95%CI (0.21–0.75) p < 0.05); no association was observed for TRAP. Dietary antioxidant capacity intake from different sources of plant foods is associated with a reduction in the risk of GC.

P-selectin mediates neutrophil rolling and recruitment in acute pancreatitis.

The adhesive mechanisms regulating leucocyte–endothelium interactions in the pancreas remain elusive, but selectins may play a role. This study examined the molecular mechanisms mediating leucocyte rolling along the endothelium in the pancreas and the therapeutic potential of targeting the rolling adhesive interaction in acute pancreatitis (AP).