Effect of helicobacter pylori infection on cell proliferation and apoptosis of gastric cancer SGC-7901

Objective To investigate the effect of Helicobacter pylori infection on cell proliferation and apoptosis of gastric cancer cell line SGC 7901. Method SGC 7901 cells were incubated with 1 × 108,5 × 107,1 × 107,5 × 106 cfu / ml concentration gradient of the standard HP NCTC 11637 strains in vitro. Morphological changes of cells were observed at 24, 48, 72 hour, respectively. Cell proliferation inhibition rate were detected with MTT assay. Apoptosis were observed by flow eytometry and TUNEL analysis, mRNA expression of survivin were detected by RT-PCR, and survivin expression were determined by western blot. Results Cell proliferation inhibition rate was 54.5%, 58.9%, 67.6%, 72.9% with 1 × 108,5 × 107, 1 × 107,5 × 106 cfu / ml concentration gradient of the HP bacteria on the role of SGC 7901 cells at 72h, respectively. The rate of apoptosis after 72h detected by flow cytometry and TUNEL with HP concentration gradient of different bacteria were 42.51%, 45.67%,48.57%, 49.51% and 54.61%, 51.26%, 59.41%, 62.46.% Helieobacter pylori could significantly reduce mRNA and protein expression of survivin. These effects were strengthened as the concentration of Helicobacter pylori increased and the time extended. Conclusion H. Pylori infection may be through reducing the expression of survivin to inhibit cell proliferation and pro-mote apoptosis of SGC 7901 in vitro. Moreover, this effect was positive related with time and dose. Key words: Helicobacter infections;  Stomach neoplasms;  Cell proliferation;  Apoptosis