Infection and Virulence Factors and (s and m Regions) in Gastric Adenocarcinoma from Pará State, Brazil.

shows a great variability in genes associated with virulence, which may influence properties related to gastric adenocarcinoma initiation and progression. Among them, and show a strong positive association with the disease. Therefore, a cross-sectional study was carried out with 281 samples of gastric adenocarcinoma, collected at a cancer reference center in the Brazilian Amazon. Detection of was proceeded by PCR of the and genes. Positive samples were subjected to the detection and typing. The bacteria were observed in 32.03% of the samples. Positivity for was associated with advanced age ( = 0.0093) and metastases ( = 0.0073). Among the positive cases, 80% (72/90) had the gene. For the "s" position of the gene, 98.8% (83/84) of the bacteria had genotype s1 and 1.2% (1/84) were genotyped as s2. For the "m" position, the results were: 63.6% (56/88) with m1 genotype, 2.3% (2/88) genotyped as m2 and 34.1% (30/88) m1/m2. Virulence factors did not impact an increase in the association with age or metastases. In conclusion, infection is associated with malignant phenotype cases of gastric adenocarcinoma, involving metastases. The virulence factors related to the and genes showed a high prevalence in the Brazilian Amazon.