The effects of cagA gene positive Hp culture filtrates on the growth of GES-1

Abstract

Objective To study the effects of CagA gene positive Hp culture filtrates on the growth of GES-1. Methods There were three groups： CagA gene positive Hp group； CagA negative group was cultivated then the Hp culture filtrates were prepared. The GES-1 cells were treated with the different culture filtrates for one month. GES-1 cells were then examined by microscopy to observe morphologic changes， growth caculations were performed to test cell growth by MTT， single cell microgel electrophoresis (SCGE) was used to detect cellular DNA damage. Blank broth filtrates was used for contrast group. Results GES-1 cells treated with CagA gene positive broth culture filtrates of Hp showed dyskaryosis， hypertrophy of nucleolus and karyokinesis. growth caculations showed GES-1 proliferated actively when treated by CagA gene positive broth culture filtrates. In this group， comet assay showed 41.2% comet cells in GES-1 cells while in CagA negative group， the number was 12.5%， significantly lesser than the CagA positive filtrates(P＜0.05). Conclusions CagA gene plays an important role in the changes of the morphology and growth character of tumor cells in human gastric epithelial treated by Hp filtrates. DNA damage may be one of the mechanisms of the changes of growth character.