Associação dos polimorfismos em genes de interleucinas (IL1B -511, IL1RN, IL6 -174G e IL8 -251) com lesões gástricas relacionadas ao Helicobacter pylori

Abstract

The gastric le sions ( G L ) develop from normal mucosa infected by Hel icobacter pylori ( H.pylori ) and can progress to gastric cancer ( GC ) through a multi - step process. The ability of H. pylori on cause G L is associated with some of their virulence factors that, when expressed , come in to c ontact with the gastric cells and pro moting activation of the innate immune response. This, in turn, activates the transcription of inflammatory cytokines such as interleukins (ILs) IL1B ( - 511), IL1RN (VTNR), IL6 ( - 174) and IL8 ( - 251). Such ILs have polymorphic genes that change expression an d , consequently , the intensity of the host inflammatory response. Therefore , this study aims to investigate the association between polymorphisms of ILs with the GC and G L in the progression to the G C . In this study DNA was obtained from 324 patients, 118 with CG and 206 with pre - malignant G L (LGPM), collected in four hospitals in Fortaleza - CE. The identification of polymorphisms was done by PCR - RFLP and PCR a nalysis and the detection of H. pylori by PCR. Genotypic analysis of the comparison between the G C a nd LGPM demonstrated an association of CG with IL8 TT genotypes (p = 0.0065), IL6 GG (p = 0.0012) and IL1RN LL (p = 0.0052 ) . The association of ILs 3x3 observed that the most inflammatory haplotypes were associated with GC , while in the analysis the 4x4 T - T - G - *2 (IL1BxIL8xIL6xIL1RN) haplotype was more related to GC (p = 2.89 × 10 5), which is a good marker for this type of cancer. In comparison with the CG and GCI it was observed the association between IL6 G allele with the G C (p = 0.0389). Comparison between GCA and GC showed that IL8 AT genotypes (p = 0.0016), IL1RN L * 2 (p = 0.0049) and IL6 GG (p = 0.0004) are associated with the GC , the analysis of the ILs association o n 4x4 showed that the T - T - G - * 2 haplotype (IL1BxIL8xIL6xIL1RN) was associated with G C (p = 5. 72 x10 - 5 ), confirming the importance of this haplotype as a good marker for the GC. In comparison with the MI CG observed a significant association with IL8 AT CG (p = 0.0426) and IL6 GG (p = 0.0475. So, it can be conclude that the genotypes of all inflammat ory IL s were associated with the CG and that, according to the h aplotype analysis , the mo st inflammatory haplotype (G - T - T - * 2 ) is a good marker for the G C .