title: Effects of Helicobacter pylori infection on the expressions of Bax and Bcl-2 in patients with chronic gastritis and gastric cancer.
abstract: The aim of the present study is to evaluate the influence of Helicobacter pylori on Bax and Bcl-2 mRNA and protein levels in patients with chronic gastritis and gastric cancer. The study included 217 patients, of which 26 were uninfected; 127 had chronic gastritis and were H. pylori-positive, and 64 had gastric cancer. Bacterial genotypes were evaluated by PCR, and the expression values were determined by quantitative real-time PCR and immunohistochemistry. Our data showed that the up-regulationary effects of H. pylori infection on the pro-apoptotic gene, Bax, were stronger than its induction of Bcl-2; this effect may increase apoptosis in patients with chronic gastritis. In patients with gastric cancer, the up-regulation of the anti-apoptotic gene, Bcl-2, counteracted the pro-apoptotic effects of Bax, leading to a deregulation of apoptosis-associated gene expression, favoring cell proliferation. Thus, the disturbance in Bax and Bcl-2 balance, induced by H. pylori, might be important in gastric cancer development.
authors.affiliation: Unidade Integrada de Farmacologia e Gastroenterologia, Universidade São Francisco, Av. São Francisco de Assis, 218. Jd. São José, Bragança Paulista, SP, Brazil.
authors.forename: Waldemar
authors.initials: W
authors.lastname: Bartchewsky
authors.forename: Mariana R
authors.initials: MR
authors.lastname: Martini
authors.forename: Aline C
authors.initials: AC
authors.lastname: Squassoni
authors.forename: Marisa C
authors.initials: MC
authors.lastname: Alvarez
authors.forename: Marcelo S P
authors.initials: MS
authors.lastname: Ladeira
authors.forename: Daisy M F
authors.initials: DM
authors.lastname: Salvatore
authors.forename: Miriam A
authors.initials: MA
authors.lastname: Trevisan
authors.forename: José
authors.initials: J
authors.lastname: Pedrazzoli
authors.forename: Marcelo L
authors.initials: ML
authors.lastname: Ribeiro
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017209:Apoptosis; D002908:Chronic Disease; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D005756:Gastritis / Q000378:metabolism* / Q000382:microbiology* / Q000473:pathology; D016481:Helicobacter Infections / Q000150:complications / Q000378:metabolism* / Q000473:pathology; D016480:Helicobacter pylori / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000382:microbiology* / Q000473:pathology; D015854:Up-Regulation; D055815:Young Adult; D051028:bcl-2-Associated X Protein / Q000378:metabolism*
chemical_list: D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein