Analysis of Helicobacter pylori infection on microssatelite instability in patients with gastric cancer.

Abstract

Helicobacter pylori appear to be responsible for triggering a pathological progression in gastric mucosa that leads to gastric cancer. The infection causes an inflammatory response which is followed by an increased production of cytokines. During the inflammatory process reactive oxygen and nitrogen species are generated in response to pro-inflammatory mediators and products of bacterial cell wall. These compounds react with DNA and protein, and can induce cell membrane damage, DNA oxidation, DNA strand breaks, and chromosomal instability. It is well known that the H. pylori affect about 80% of the Brazilian population, and the infection caused by this organism is often asymptomatic. In this respect, this project aims to identify strains that would be potentially more pathogenic and therefore would be responsible for the progression / development of malignant lesions. Additionally little is known about the effects of bacterial density in the neoplastic process, and there are no studies associating the density with bacterial genotyping. Taking into account the carcinogenic potential of this bacterium, it is intended, for correlating the data with the aforementioned genetic instability, which is strongly associated with neoplastic transformation and tumor progression