Effect of Helicobacter pylori VacA on gene expression of gastric cancer cells.
OBJECTIVE
To determine the effect of Helicobacter pylori VacA on gene expression of gastric cancer cells.


METHODS
Gene expression profile of a gastric cancer cell line, SGC7901, after challenged by VacA+ and VacA- H pylori broth culture supernatants (BCS), was detected by the cDNA microarray technique. Cytoskeleton changes of SGC7901 and HeLa cells were observed through high-resolution laser scanning confocal microscopy.


RESULTS
A total of 16,000 cDNA clones were detected. The percentage of genes with heterogeneous expression in SGC7901 cells challenged by VacA+ BCS reached 5%, compared with that challenged by VacA- BCS. There were 865 genes/EST with 2-fold differential expression levels and 198 genes/EST with 3-fold differential expression levels. Most of these genes were involved in vital cell events including signal transduction, regulation of gene expression, cytoskeleton, apoptosis, stress response and inflammation, cell cycle and tumor development. Cells co-cultured with VacA+ BCS showed collapsed and disrupted microtubular cytoarchitecture.


CONCLUSIONS
VacA+ BCS can disrupt cytoskeletal architecture, likely through affecting the expression of cytoskeleton-associated genes, directly induce the expression of tumor promoter-related genes and inhibit the expression of tumor suppressor genes, thus favoring the development of tumors. VacA+ BCS can also alter the expression of inflammation and stress response genes. This suggests that VacA may play an important role in the pathogenicity of H pylori.
Wang
Hong-Tao
HT
Department of Microbiology and Parasitology, Shanghai Second Medical University, Shanghai 20025, China.
Li
Zhen-Hong
ZH
Yuan
Jian-Ping
JP
Zhao
Wei
W
Shi
Xiao-Dong
XD
Tong
Shan-Qing
SQ
Guo
Xiao-Kui
XK
D001426:Bacterial Proteins / Q000235:genetics*; D003599:Cytoskeleton / Q000502:physiology; D015964:Gene Expression Regulation, Bacterial; D015972:Gene Expression Regulation, Neoplastic; D006367:HeLa Cells; D016481:Helicobacter Infections / Q000235:genetics* / Q000503:physiopathology; D016480:Helicobacter pylori / Q000235:genetics / Q000472:pathogenicity*; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D013274:Stomach Neoplasms / Q000235:genetics* / Q000382:microbiology / Q000503:physiopathology; D014774:Virulence
D001426:Bacterial Proteins; C074689:VacA protein, Helicobacter pylori