Inhibitory effects of magnesium hydroxide on c-myc expression and cell proliferation induced by methylazoxymethanol acetate in rat colon.
The effects of magnesium hydroxide were examined on methylazoxymethanol (MAM) acetate-induced c-myc expression and cell proliferation of colonic mucosal epithelium in rats. Rats were divided into four groups and treated as follows: MAM acetate alone (25 mg/kg i.p. injection, five times, once a week for 5 weeks), MAM acetate and feeding of 0.2% magnesium hydroxide in diet, magnesium hydroxide alone and non-treatment. At 4, 8 and 16 weeks after the start of experiment, 10 rats in each group were sacrificed. Magnesium hydroxide inhibited the MAM-induced expression of c-myc proto-oncogene, and also suppressed the increased bromodeoxyuridine (BrdU) and proliferating cell nuclear antigen (PCNA) labelling indexes induced by MAM acetate in colon mucosa in initiation and post-initiation phase. These results suggest that the anti-carcinogenic effect of magnesium hydroxide on rat colon carcinogenesis induced by MAM acetate may be related to the inhibition of the carcinogen-induced expression of c-myc proto-oncogene and cell proliferation.
Wang
A
A
Department of Pathology, Gifu University School of Medicine, Japan.
Yoshimi
N
N
Tanaka
T
T
Mori
H
H
D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D000951:Antigens, Neoplasm / Q000032:analysis; D001973:Bromodeoxyuridine / Q000032:analysis; D002455:Cell Division / Q000187:drug effects; D003110:Colonic Neoplasms / Q000139:chemically induced / Q000235:genetics*; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D016259:Genes, myc / Q000187:drug effects*; D007150:Immunohistochemistry; D008276:Magnesium Hydroxide / Q000494:pharmacology*; D008297:Male; D008746:Methylazoxymethanol Acetate / Q000633:toxicity; D009687:Nuclear Proteins / Q000032:analysis; D018809:Proliferating Cell Nuclear Antigen; D051381:Rats; D011916:Rats, Inbred F344
D016588:Anticarcinogenic Agents; D000951:Antigens, Neoplasm; D009687:Nuclear Proteins; D018809:Proliferating Cell Nuclear Antigen; D008746:Methylazoxymethanol Acetate; D001973:Bromodeoxyuridine; D008276:Magnesium Hydroxide