Furthermore, H. pylori infection has a synergistic effect on the development of GC with IL-1β gene polymorphisms, and the highest prevalence of severe gastric abnormalities are found in patients with both host and bacterial high-risk genotypes (cagA(+)/vacAs1(+)/IL-1β-511T).
Subgroup analysis showed a significant correlation between IL-1β-511C/T polymorphism and susceptibility to gastric cancer in residents of southern China and in patients with intestinal-type gastric cancer, but not in residents of northern China or in patients with diffuse gastric cancer.
The pro-inflammatory cytokine IL-1β plays a crucial role in the development of gastric tumors, and polymorphisms in the IL-1 gene cluster resulting in increased IL-1β production have been associated with increased risk for gastric cancer.
IFN-γ and IL-10 levels were significantly higher in early (I/II) and late stage (III/IV) gastric cancer; IL-1β and IL-8 were higher and MCP-1 was lower only in late stage (IV) patients.
Further, meta-analysis revealed significant association of IL-1βrs1143627: T > C (p = 0.026; OR = 4.165; 95% CI 1.18-14.65) and rs16944: C > T (p = 0.01; OR = 5.49; 95% CI 1.48-20.37) in presence of H. pylori with gastric cancer in Asian population though no significant difference (p > 0.05) was found when compared to absence of H. pylori .