项目组从胃癌及胃炎患者胃粘膜中分离培养出20株Hp，通过细胞感染及动物感染模型筛选出致癌的毒力菌株，通过芯片杂交发现该菌株共培养的胃上皮细胞TRAF1、4-1BB及NF-κB通路下游抗凋亡因子上调。进一步发现TRAF1、4-1BB在萎缩、肠化伴不典型增生的临床组织标本中表达亦升高，且与组织中Hp的cagAvacAs1m1基因型有密切相关性。本项目将在前期基础上，进一步研究：1.在胃癌前及癌组织中确定Hp的cagAvacAs1m1基因亚型重组的规律。2.构建不同毒力因子基因亚型的质粒，观察质粒对GES-1细胞生物学行为的影响；利用NF-κB荧光素酶报告载体等手段及siRNA沉默TRAF1，阐明Hp通过上调TRAF1、4-1BB激活NF-κB信号通路、启动炎症恶性化的机制。3.利用动物感染模型，了解在不同病理变化节点根除Hp能否阻断癌变发展的进程，确定抗Hp治疗干预显效的病理学进展临界点。

In our preliminary study，we isolated 20 H. pylori strains from the gastric mucosa of gastric cancer and gastritis patients. The virulence of H. pylori strains were determined by animal and GES-1 cell model with H. pylori infection. Some target genes were found valuable by gene chips. The upregulated expression of either TRAF1/4-1BB or genes induced by NF-κB pathway brought our attention. These kinds of up-regulation were also found in atrophy、intestinal metaplasia with atypical hyperplasia clinical specimens and were closely linked to the cagAvacAs1m1 virulence genotypes of H. pylori. In this study，we will conduct further projects. Firstly, Collected H. pylori-positive samples including precancerous lesions and gastric cancer are used to inquire the characteristics of cagAvacAs1m1genetic subtype restructuring patterns；Secondly, Eukaryotic expression plasmids of different virulence factor genomic subtypes will be used to observe the effects of different virulence factor genomic subtypes acting on GES–1 cell biology behaviors. Based on nf-kappa B luciferase report carrier and TRAF1 gene silence siRNA，We will investigate the mechanisms of cagAvacAs1m1 activating the nf-kappa B signaling pathways through raising TRAF1, 4-1BB. Thirdly, Mongolian gerbil model in which gastric inflammation and gastric cancer are induced with the infection of highly virulent H. pylori is established to determine the critical point of pathological progress whether H. pylori eradication taking effect or not.

项目组从胃癌及胃炎患者胃粘膜中分离培养出20株Hp，通过细胞感染及动物感染模型筛选出致癌的毒力菌株，通过芯片杂交发现该菌株共培养的胃上皮细胞TRAF1、4-1BB及NF-κB通路下游抗凋亡因子上调。进一步发现TRAF1、4-1BB在萎缩、肠化伴不典型增生的临床组织标本中表达亦升高，且与组织中Hp的cagAvacAs1m1基因型有密切相关性。本项目在前期基础上，收集了伴H.pylori感染胃“炎-癌”不同病理阶段的临床标本，通过PCR、免疫组化检测发现H.pylori感染胃“炎-癌”组织中毒力因子vacA亚基以vacAs1b+/ml+基因型分布为主；4-1BB、TRAF1、Bcl-xL、IL-8在慢性非萎缩性胃炎、萎缩性胃炎、肠化伴非典型增生和胃癌组织中的表达有逐渐上调的趋势，且胃癌组较非萎缩性胃炎组表达明显增强；成功构建了vacA、cagA真核质粒细胞转染模型，初步验证vacA质粒转染GES-1细胞可上调TRAF1、4-1BB及IL-8的表达，发现cagA质粒转染GES-1细胞可上调TRAF1/4-1BB表达，激活NF-κB通路使下游趋化因子IL-8表达升高，发挥促进细胞增殖、抑制细胞凋亡的作用。本研究提示vacAslb+/vacAml+型H. Pylori菌株与胃癌发生发展密切相关，初步验证了“vacA/cagA→TRAF1→炎症NF-κB通路相关基因→IL-8”调控轴的存在，为后续进一步揭示H.pylori致炎-癌机制提供更多的线索。