Effect of early eradication on Helicobacter pylori-related gastric carcinogenesis in Mongolian gerbils.
Helicobacter pylori (Hp) infection and gastric carcinogenesis are known to have a close relationship, but the effect of eradication of Hp on Hp-related gastric carcinogenesis has not been fully studied experimentally. To evaluate the effect of eradication in gastric carcinogenesis, an experimental model with eradication in the early, middle or late period was studied using Hp-infected and N-methyl-N-nitrosourea (MNU)-treated Mongolian gerbils. The animals were divided into seven groups: group A (MNU + Hp + eradication at 15 w), group B (MNU + Hp + eradication at 35 w), group C (MNU + Hp + eradication at 55 w), group D (MNU + Hp), group E (MNU), group F (Hp) and group G (control). The tumor incidences at week 75 in the early (group A), middle (group B) and late (group C) eradicated groups were 6.7%, 27.3% and 38.2%, respectively. The incidence of 56.3% in the non-eradicated group was the highest (group D). Incidences in group E, group F and group G were 6.3%, 0.0% and 0.0%, respectively. The tumor incidences were related to the period of inflammatory status induced by Hp infection. Hp infection strongly enhanced gastric carcinogenesis initiated with a chemical carcinogen, and following eradication at an early period this enhancing effect was effectively reduced. Eradication at an early stage of inflammation might be effective in preventing Hp-related gastric carcinogenesis.
Nozaki
Koji
K
Division of Oncological Pathology, Aichi Cancer Center Research Institute, Chikusa-ku, Nagoya, Aichi 464-8681, Japan.
Shimizu
Nobuyuki
N
Ikehara
Yuzuru
Y
Inoue
Manami
M
Tsukamoto
Tetsuya
T
Inada
Ken-ichi
K
Tanaka
Harunari
H
Kumagai
Toshiko
T
Kaminishi
Michio
M
Tatematsu
Masae
M
D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D002276:Carcinoid Tumor / Q000139:chemically induced / Q000453:epidemiology / Q000382:microbiology* / Q000473:pathology / Q000517:prevention & control; D004195:Disease Models, Animal; D005849:Gerbillinae; D016481:Helicobacter Infections / Q000188:drug therapy / Q000517:prevention & control*; D016480:Helicobacter pylori; D015994:Incidence; D008770:Methylnitrosourea; D013274:Stomach Neoplasms / Q000139:chemically induced / Q000453:epidemiology / Q000382:microbiology* / Q000473:pathology / Q000517:prevention & control
D000900:Anti-Bacterial Agents; D008770:Methylnitrosourea