Expression Level Of COX-2 In Gastric Cancer Cells Among Coalminers Infected By Helicobacter Pylori

Objective Coal miners is a specific occupational groups, the special working environment and lifestyle formed a unique spectrum of disease - gastrointestinal diseases, especially gastric cancer.Gastric cancer is the most common gastrointestinal malignancy.it is a serious hazard for the majority of coal workers .Since 1983, Wallen and Mashall found that Helicobacter pylori (Helicobacter pylori, Hp) has been growing its relationship with gastric diseases,then attention has been paid.Hp infection induces a complex immune response, including the first accumulation of inflammatory cells and lead to proliferation, cytokine release, leading to molecular changes. In the target genes were upregulated in Hp, which cyclooxygenaseⅡ(COX-2) in gastric cancer plays a major role in the process. CyclooxygenaseⅡ(COX-2) is the synthesis of prostaglandin of arachidonic acid limiting enzymes, not only start the inflammatory response, but also participate in a variety of tumors and the development process. A large number of studies have shown that COX-2 in tumor tissues showed high expression in gastric cancer and other digestive tumors. The expression of COX-2 may play a important role in the development and transfer of cancer cells.Therefore, detection of the expression level of COX-2 in gastric cancer cell lines from infection of Hp will help to further clarify the possible mechanism of Hp gastric carcinogenesis.To further study the pathogenesis of gastric cancer induced by Hp, and to provid theory and experimental evidence for cancer prevention and control, the expression level of COX-2 was analized.MethodsThe study population ware devided into 4groups,coal miners HpCagA~+ group,non-coal miners HpCagA~+ group, coal miners HpCagA~-group, and non-coal miners HpCagA~- group as control. The Hp strans from 4 groups ware cultured together with MKN28, MKN45, and BGC823 cancer cell mixed culture by 1:100 for 24hs. Data base from investigation and test of laboratory was estabblishied with Excel, and stastistic was conducted with software of SPSS13.0. ResultsLaboratory culture results: 130 specimens of gastric mucosawas celected, 45 was Hp positive, and other 85 was negative by the result of culture. And CagA genotypes were classified, including CagA +40 copies, CagA~-5 copies by the result of PCR.The results of Western-blotting: The Hp strans from 4 groups ware cultured together with MKN28, MKN45, and BGC823 cancer cell mixed culture by 1:100 for 24hs. The expression level of COX-2 in gastric cancer cell lines was no significant difference (P> 0.05), but compared with the control group the expression than that were higher (P<0.05),and the difference is significant. The expression level of COX-2 in MKN28 cancer cell is 2 times of the control group,and in MKN45 or BGC823 cancer cell was 3.6 times of the control group .Conclusion: The increased expression of COX-2 may play a important role in the development of gastric cancer due to the infection of Hp,and the expression in gastric cancer celes.