Helicobacter Infection And Its Impact On The Proliferation And Apoptosis Of Human Esophageal Cancer Cell Line Eca-109

ObjectiveTo investigate whether there is an infection of Helicobacter in esophageal carcinoma and the influence of Helicobacter on the proliferation and apoptosis of human esophageal cell line Eca-109 cells in vitro experiment for exploration of Helicobacter infection in the significance of occurence of human esophageal carcinoma.Methods38 samples of esophageal carcinoma and 12 samples of normal esophageal tissues were randomly collected.Helicobacter-specific 16S rDNA were amplified with polymerase chain reaction(PCR).The target amplification products were sequenced and compared with 16S rDNA of H.pylori.published by GenBank.Then esophageal cancer cell line(Eca-109) was cocultured with sonicated extract of standard strain of H.pylori,which was followed by detections of cellular proliferation with MTT method,mRNA expression of proliferating cell nuclear antigen(PCNA) with semi-quantitative RT-PCR and cell apoptosis with flow cytometry.Results16S rDNA of Helicobacter species was found in esophageal cancer tissue in 34.2%(13/38) of patients with squamous carcinoma whereas none of the DNA of normal controls was detected.Four of Helicobacte-specific PCR amplicons were sequenced and compared with 16S rDNA of H.pylori published by GenBank in which 99-100%of homology was found. After Eca-109 was cocultured with different concentrations of sonicated extract of H.pylori, cell proliferation was obviously observed at low concentration of the extract.But Eca-109 cell apoptosis appeared at higher concentration.PCNA mRNA was increased compared with that of uninfected control.As demonstrated by flow cytometry,the sonicated extract of H.pylori induced the cell apopotosis with the rate increased in a concentration-dependent manner. ConclutionsHelicobacteraceae 16S rDNA are found in human esophageal carcinoma tissues which shows the infection of Helicobacter species likely H.pylori or other subspecies of Helicobacter.Helicobacter might be as one of the causes of contributing to generation and development of human esophageal carcinoma,in the mechanism of which the pathogen likely reproduces to a lower extent in esophageal mucosa and persistently lead to chronic inflammation resulting in persistent over expression of PCNA mRNA and unbalance between the cell proliferation and apoptosis.