BACKGROUND - Incidence and mortality rates for gastric cancer, the fifth most commonly diagnosed and third most deadly cancer worldwide, are highest in East Asia. We sought to identify gastric cancer risk biomarkers among eight prospective studies from China, Japan and Korea.
METHODS - This pooled nested case-control study included 1608 incident non-cardia gastric cancer cases and 1958 matched controls. Pre-diagnostic antibody levels to 15 Helicobacter pylori proteins were assessed using multiplex serology. Conditional logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs).
RESULTS - Sero-positivity to 10 H. pylori antigens (Omp, CagA, VacA, HcpC, HP 0305, GroEL, NapA, HyuA, Cad, HpaA) was associated with a 1.29- to 3.26-fold increase in odds of gastric cancer. Omp and HP 0305 consistently remained associated with gastric cancer risk after mutually adjusting for all other markers. Sero-positivity to both Omp and HP 0305 was associated with an over 4-fold increase in gastric cancer incidence (OR, 4.09; 95% CI 3.26-5.13). When limited to only those who are CagA+ H. pylori+, Omp/HP 0305 sero-positivity remained strongly associated with an over 3-fold increase in the odds of gastric cancer (OR, 3.34; 95% CI 2.27-4.91). The results were highly consistent among the cohorts.
CONCLUSIONS - We have confirmed new H. pylori biomarkers that are strongly associated with gastric cancer risk, even among those infected with the known H. pylori virulence factor CagA. These results may help to design cost-efficient prevention strategies to reduce gastric cancer incidence in East Asia.
© The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.