Abstract 1052: Associations of Helicobacter pylori biomarkers with lung cancer risk among low-income and African American populations: Results from the Southern Community Cohort Study
Authors: Yoon Hyung-Suk , Zheng Wei , Cai Hui , Wu Jie , Wen Wanqing , Courtney Regina , Michel Angelika , Pawlita Michael , Waterboer Tim , Cai Qiuyin 
Published: September 2020

Abstract
Lung cancer is the leading cause of cancer death in the United States and many other countries. Helicobacter pylori (H. pylori), a Group 1 carcinogen classified by IARC, is a common bacteria infecting humans. Emerging evidence supports a possible etiological role of H. pylori infection in lung cancer. H. pylori has evolved over time to become highly genetically diverse, with substantial variations in the presence or levels of virulence factors. To evaluate the associations of lung cancer risk with H. pylori seropositivity, overall and by antigen-specific biomarkers, we conducted a nested case-control study using resources from the Southern Community Cohort Study (SCCS) including ~86,000 participants, two-thirds of whom are African American. A total of 295 incident lung cancer cases and 295 matched controls were included in this study. Controls were matched to cases on age, sex, race, recruitment site and date of blood draw. H. pylori multiplex serology assay was performed to detect levels of IgA, IgM and IgG antibodies to 15 H. pylori proteins. Overall H. pylori seropositivity (H. pylori+) was defined as being positive to any 4 or more H. pylori antigens. Individual H. pylori antigens were considered as seropositive only when the sample was simultaneously considered overall H. pylori+, which ensured that antigen-specific seropositivity was not based on cross-reactive antibody responses from infection with other pathogens expressing homologous proteins. Multivariable logistic regression models were used to estimate odds ratios (ORs) and corresponding confidence intervals (95% CIs) for lung cancer risk associated with seropositivity of H. pylori after adjusting for age, smoking status, pack-years, alcohol consumption, education, household income, BMI and history of COPD. Overall H. pylori+ was associated with a non-statistically significant increased lung cancer risk (OR, 1.29; 95% CI, 0.85-1.95). Associations were stronger for H. pylori+ VacA+ (OR, 1.64; 95% CI, 1.02-2.62) and H. pylori+ Catalase+ (OR, 1.75; 95% CI, 1.11-2.77), the latter more so among African Americans (OR, 2.09; 95% CI, 1.11-3.95) than European Americans (OR, 1.20; 95% CI, 0.56-2.54). Among people who smoked ≥ 30 pack-years, overall H. pylori+ (OR, 1.85; 95% CI, 1.02-3.35), H. pylori+ CagA+ (OR, 2.77; 95% CI, 1.35-5.70), H. pylori+ VacA+ (OR, 2.53; 95% CI, 1.25-5.13) and H. pylori+ Omp+ (OR, 2.01; 95% CI, 1.07-3.77) were associated with increased lung cancer risk. Among current and former smokers, significant interactions were observed for H. pylori+ CagA+ (p for interaction = 0.01) and H. pylori+ VacA+ (p for interaction = 0.03) between those who smoked ≥ 30 pack-years and those who smoked &lt; 30 pack-years. In summary, our results indicate that H. pylori infection may be associated with an elevated risk of lung cancer, and the associated risk might differ by antigen-specific H. pylori biomarkers and smoking amount. Further studies are warranted to confirm our findings.
Citation Format: Hyung-Suk Yoon, Wei Zheng, Hui Cai, Jie Wu, Wanqing Wen, Regina Courtney, Angelika Michel, Michael Pawlita, Tim Waterboer, Qiuyin Cai. Associations of Helicobacter pylori biomarkers with lung cancer risk among low-income and African American populations: Results from the Southern Community Cohort Study [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1052.