Prospective study of Helicobacter pylori biomarkers for gastric cancer risk among Chinese men
Menée sur 226 patients atteints d'un cancer de l'estomac et sur 451 témoins, cette étude chinoise évalue l'association entre les niveaux sériques de 15 anticorps ciblant des protéines de la bactérie Helicobacter pylori et le risque de développer la maladie
Background: Helicobacter pylori is the leading risk factor for gastric cancer, yet only a fraction of infected individuals ever develop neoplasia. Methods: To identify potential predictive biomarkers, we assessed the association of 15 antibodies to Helicobacter pylori proteins and gastric cancer in a nested case-control study. Blood levels of antibodies were assessed using multiplex serology for 226 incident cases and 451 matched controls from the Shanghai Men's Health Study. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression. Results: Sero-positivity to four (Omp, HP0305, HyuA, and HpaA) proteins were associated with a one-and-a-half to three-fold increased risk for gastric cancer. When excluding cases diagnosed within two years of study enrollment, sero-positivity to two additional proteins (CagA and VacA) showed significant associations with risk. Compared to individuals with ≤3 sero-positive results to the six virulent proteins identified in this population, individuals with 4-5 sero-posit ive results were at a two-fold increased risk (OR=2.08, 95% CI: 1.31-3.30) and individuals sero-positive to all 6 proteins had a three-and-a-half-fold increase in risk (OR=3.49, 95% CI: 2.00-6.11) for gastric cancer. Among individuals diagnosed at least two years after study enrollment, these associations were even stronger (OR=2.79 and OR=4.16, respectively). Conclusions: Increasing number of sero-positives to six H. pylori proteins may be a risk marker for distal gastric cancer in China. Impact: In a population with a 90% prevalence of CagA-positive H. pylori infection, assessment of additional virulent H. pylori proteins might better identify individuals at high risk for gastric cancer.
Cancer Epidemiology Biomarkers & Prevention , résumé, 2012