Serum Antibodies against Helicobacter pylori Neutrophil Activating Protein in Carriers of IL-4 C-590T Genetic Polymorphism Amplify the Risk of Gastritis and Gastric Cancer

Background: Gastric cancer arises, mainly, on an inflammatory background. Helicobocter pylori neutrophil activating [HP-NAP] protein functions as a potent pro-inflammatory mediator. Similarly, IL-4 plays a critical role in the inflammation pathway, the levels of which are altered by C to T transition at position -590 in its promoter region. Here, we have aimed to assess the risk of gastritis and gastric cancer in the co-presence of these two inflammation modulating mediators

Methods: Gastritis [n=58] and gastric cancer [n=31] patients were evaluated and compared with H. py/or/-positive asymptomatic controls [n=46], for serum antibodies against recombinant HP-NAP and IL-4 C-590T single nucleotide polymorphism using immunoblotting and PCR-RFLP, respectively. Multivariable logistic regression, adjusting for age, gender and ethnicity, was used for data analysis

Results: In terms of susceptibility to gastritis, seropositivity to HP-NAP projected a risk impact of 4.62 fold [OR=4.62, 95% Cl=l.50-14.22], which when present in IL-4 -590 T carriers augmented the risk up to 9.7 fold [OR=9.70, 95% CI=2.06-45.69]

A similar pattern, but of a stronger magnitude, occurred for the risk of gastric cancer, which was estimated at 9.07 fold [OR=9.07, 95% Cl=1.99-42.0] for HP-NAP-seropositive subjects and was drastically amplified [OR=33.64, 95% 0=2.06-548.68], when double-positive [HP-NAP seropositive/IL-4 -590 T carrier] subjects were examined against double negatives [HP-NAP seronegative/IL-4 -590 CC]

Conclusion: Our preliminary data indicate that serum antibodies against HP-NAP represent a state of risk, which is further exacerbated in IL-4 -590 T carriers. These biomarkers, if validated in larger prospective studies, can be used to screen for gastric cancer susceptibility

Age-specific gastric cancer risk indicated by the combination of Helicobacter pylori sero-status and serum pepsinogen levels

Serologic screening of gastric cancer [GC] by serum pepsinogens [sPG] levels and Helicobacter pylori [Hp] sero-status, though highly informative, has provided heterogeneous results. Here, we have evaluated the modifying effects of demographic factors on the risk impact of Hp sero-status/sPG levels in gastric cancer, with particular emphasis on age. A cross-sectional study was carried out on 1341 individuals [GC = 578, healthy = 763], who were stratified into two age groups: 35-59 years [middle-aged, n = 830] and >/= 60 years [60 years-plus, n = 511]. Demographic factors and serological states [Hp sero-staus and sPG levels] were recorded by subject interview and serum ELISAs, respectively. Covariate-specific odds ratios were calculated by multivariable logistic regression. Hp infection was consistently associated with increased sPGI and sPGII levels in the 60 year-plus, but not the middle-aged group. The joint examination of the variable states of the three serum biomarkers [Hp serology, sPGI, and sPGI/II ratio], in the 60 year-plus age group, demonstrated a stepwise escalation of risk from the single [sPGI[low]; OR = 2.6], to double [sPGI[low]/sPGI/II[low]; OR = 3.55, and Hp[positive]/sPGI[low]; OR = 5.0] and ultimately triple [Hp[positive]/PGI[low]/PGI/II[low]; OR = 10.48] positive states, in reference to the triple negatives. However, this pattern was not exhibited in the middle-aged subjects. Age was clearly identified as a modifying factor on the risk projection of the combined states of Hp serology and sPG levels in gastric cancer screening, reflected by the augmented [tilde10.5 fold] risk of GC in the triple positive [Hp[positive]/sPGI[low]/sPGI/II[low]] 60 year-plus subjects, which was not evident in the middle-aged group