678P - Increased gene expression of cytokines induced by H. pylori infection and changes after eradication therapy

Date 29 September 2014
Event ESMO 2014
Session Poster Display session
Topics Gastrointestinal Cancers
Translational Research
Surgery and/or Radiotherapy of Cancer
Presenter Ana Silva
Citation Annals of Oncology (2014) 25 (suppl_4): iv210-iv253. 10.1093/annonc/mdu334
Authors A.E. Silva, A.F.T. Rossi, A.C.T. Cadamuro, J.M. Biselli-Périco
  • Biology, São Paulo State University - Unesp, 15054-000 - São José do Rio Preto/BR

Abstract

Aim

Chronic inflammation resulting from H. pylori infection is a risk factor for gastric cancer development, while the eradication of this bacterium can prevent malignant transformation. So, the aim of this study was to evaluate the mRNA quantitative expression of cytokines genes and receptors (TNFA, IL1B, IL6, IL12A, IL2 and TGFBRII) in patients with chronic H. pylori-positive gastritis before and after eradication treatment.

Methods

Relative quantification (RQ) of mRNA expression was performed using specific probes for the target genes and ACTB and GAPDH reference genes by qPCR (TaqMan® gene expression assay). A total of 40 biopsies from patients with chronic gastritis were evaluated [28 H. pylori-positive (Hp+) before and 2-3 months after treatment, and 12 H. pylori-negative (Hp-)]. Wilcoxon signed-rank test was used to compare the groups before and after therapy.

Results

TGFBRII showed reduced gene expression (RQ < 1.0) in Hp+ (before and after therapy) group, whereas IL2 did not present alteration in the expression levels. The other cytokine genes showed increased expression in the Hp+ group (RQ IL1B= 1.85; RQ IL6 = 7.39; RQ IL12A = 2.24; RQ TNFA = 2.58), however only TNFA (RQ = 1.44) presented significant decrease in gene expression after bacterium eradication (p < 0.01). Among the patients treated, six remained infected and the expression levels of IL6, IL12A and TNFA genes maintained increased expression after treatment (RQ = 8,51; 4.62 and 3.07, respectively) for this group. The Hp-negative group showed increased expression for IL1B (RQ = 1.78) and reduced for TGFBRII (RQ = 0.74), while for the others genes basal expression was observed (RQ ∼ 1.0).

Conclusions

H. pylori infection increases the gene expression of inflammatory mediators that regulates the chronic inflammation such as TNFA, IL1B, IL6 and IL12A, however the eradication of bacterium does not completely normalize the gene expression of these cytokines, although TNFA expression has been reduced.

Disclosure

All authors have declared no conflicts of interest.