CagA^+幽门螺杆菌菌株培养滤液对胃黏膜上皮细胞生长及DNA的影响

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

目的研究CagA+Hp菌株培养滤液对胃黏膜上皮细胞(GES-1)生长的作用。方法分为CagA+组、CagA-组、布氏肉汤组(空白对照组),Hp菌株制备培养滤液处理GES-1细胞,连续培养1个月。MTT法观察GES-1细胞生长,单细胞微凝胶电泳检测GES-1细胞DNA的损伤,并采用电镜观察GES-1细胞的形态变化。结果 CagA+培养滤液可使GES-1细胞增生活跃,GES-1细胞出现彗星现象显著高于CagA-组(41.2%vs.12.5%)(P<0.05)。经CagA+组处理的GES-1细胞,细胞核增大、畸形、核染色质变粗、核仁肥大、核分裂。结论 CagA在Hp培养滤液促使GES-1细胞呈肿瘤细胞的形态学改变及生长特征中起重要作用。DNA损伤可能是CagA诱导GES-1生长特征改变的机制之一。

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.