Difference of p53AIP1 mRNA expression in gastric mucosa between patients with gastric cancer and chronic gastritis infected with Helicobacter pylori.
OBJECTIVE
To examine the significance of alteration of p53-regulated apoptosis-induced protein 1 (p53AIP1) expression in gastric carcinogenesis in patients with Helicobacter pylori infection.


BACKGROUND
H. pylori infection induces gastric mucosal inflammation and DNA damage of epithelial cells, which associate with gastric carcinogenesis. p53AIP1 is expressed after DNA damage and induces apoptosis in human cell lines.


METHODS
Endoscopic antral and corpus biopsies were obtained from 13 patients with chronic gastritis and 17 with gastric cancer. Expression of p53AIP1 and p53DINP1 mRNA was examined by semiquantitative reverse transcription polymerase chain reaction and mutation of p53 codon-46 was studied by direct sequence analysis. The grade of gastritis was assessed according to the updated Sydney System. Results were compared between patients with gastric cancer and chronic gastritis.


RESULTS
In the antrum, p53AIP1 mRNA expression was significantly lower in patients with gastric cancer than in those with chronic gastritis (P<0.05). In patients with chronic gastritis, expression of p53AIP1 mRNA was significantly higher in the antrum than in the corpus (P<0.05). In patients with chronic gastritis, antral mucosa with high p53AIP1 expression tended to have severe intestinal metaplasia. No mutation was found at p53 codon-46.


CONCLUSIONS
In H. pylori-infected gastric mucosa expression of p53AIP1 would be higher when the inflammation is severe or intestinal metaplasia is present. Insufficient expression of p53AIP1 may play a role in gastric carcinogenesis in patients infected with H. pylori infection.
Sawaya
Manabu
M
First Department of Internal Medicine, Hirosaki University School of Medicine, 5 Zaifu-cho, Hirosaki, Japan.
Yoshimura
Tetsuro
T
Shimoyama
Tadashi
T
Munakata
Akihiro
A
Fukuda
Shinsaku
S
D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins / Q000096:biosynthesis / Q000235:genetics*; D001706:Biopsy; D002352:Carrier Proteins / Q000096:biosynthesis / Q000235:genetics; D045744:Cell Line, Tumor; D003062:Codon / Q000235:genetics; D016099:Endoscopy, Gastrointestinal; D005260:Female; D005500:Follow-Up Studies; D005748:Gastric Fundus / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D005753:Gastric Mucosa / Q000378:metabolism* / Q000382:microbiology / Q000473:pathology; D005756:Gastritis / Q000150:complications / Q000235:genetics* / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic; D016158:Genes, p53 / Q000235:genetics; D006360:Heat-Shock Proteins / Q000096:biosynthesis / Q000235:genetics; D016481:Helicobacter Infections / Q000150:complications* / Q000382:microbiology / Q000473:pathology; D016480:Helicobacter pylori / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011379:Prognosis; D011446:Prospective Studies; D011706:Pyloric Antrum / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D012329:RNA, Bacterial / Q000032:analysis; D012334:RNA, Neoplasm / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000150:complications / Q000235:genetics* / Q000473:pathology
D051017:Apoptosis Regulatory Proteins; D002352:Carrier Proteins; D003062:Codon; D006360:Heat-Shock Proteins; C414742:P53AIP1 protein, human; D012329:RNA, Bacterial; D012334:RNA, Neoplasm; C429767:TP53INP1 protein, human