1. Helicobacter Pylori Lipopolysaccharide Regulates The Expression Of SOX9 And Its Effects On Proliferation And Apoptosis Of Gastric Cancer Cells 2. The Relationship Between Dicer Expression And Helicobacter Pylori Infection And Inflammation

Introduction and aims:The study was conducted to investigate expression of SOX9 regulated by Helicobacter pylori lipopolysaccharide and its influence on the apoptosis and growth of human gastric carcinoma cell.Methods:Immunohistochemistry,western-blot and Real-time PCR were used to evaluate the expression of SOX9 in 20 Helicobacter pylori positive mucosal epithelial tissues and 20 negative ones,as well as 15 pairs of early gastric cancer tissues and non-cancerous tissues adjacent to the tumor.Human gastric carcinoma cell MKN45 and AGS were stimulated by LPS with different concentrations of 0μg/ml,1μg/ml and 10μg/ml.The protein and mRNA levels of SOX9 were detected by western-blot and Real-time PCR.Small interfering RNA(siRNA)targeting SOX9 was transfected into MKN45 and AGS cells.Cell apoptosis and growth were observed by flow cytometry(FCM)and CCK-8 cell counting.Results:The expression of SOX9 was increased in the Helicobacter pylori positive tissues than negative ones(P<0.05),while elevated expression of SOX9 was detected in early gastric cancer tissues than non-cancerous tissues(P<0.05).The protein and mRNA level of SOX9 in MKN45 and AGS cells were increased with the concentration of LPS increasing(P<0.05).The apoptosis rate of MKN45 and AGS transfected by SOX9-siRNA were 47.6%and 26.7%separately,which were significantly higher than controls(8.79%and 9.2%).The cell growth of the two gastric cancer cells were also greatly inhibited(P<0.05).Conclusion:In our study,the results revealed that Helicobacter pylori LPS could regulate expression of SOX9 and effect the apoptosis and growth of human gastric carcinoma cell.Introduction and aims:The study was conducted to investigate expression of dicer in gastric mucosa infected with Helicobacter pylori and the relationship with inflammation.Methods:Real-time PCR and Immunohistochemistry were applied to detect the expression of dicer in 60 Helicobacter pylori positive mucosal epithelial tissues and 20 negative ones.The classification and grading of gastritis were performed according to the international conference on chronic gastritis consensus opinions in 2000.Results:The expression of dicer was low in the Helicobacter pylori positive tissue than negative by the above experiment results(P<0.01).The stronger dicer expression was observed in mild inflammation tissue than moderate and severe inflammation ones(P<0.05).No significant difference was observed between moderate and severe inflammation tissues(P>0.05).Conclusion:Dicer may play an important role in the inflammatory lesions of gastric mucosa caused by Helicobacter pylori infection.