The purpose of this study was to determine whether PEIT, a vegetable-derived cancer chemopreventive agent inhibits HBPE carcinogenesis mediated by N-methyl-N-benzylnitrosamine(M-BN). PEIT(50mM) in corn oil(CO) was topically applied to both buccal pouches of three hamsters(group 1), thrice-weekly for 2 weeks followed by twice-weekly(Monday/Thursday) topical treatments of a mixture of MBN and PEIT(both at 50mM) for 22 weeks. During the 22 weeks of MBN treatment, the group 1 hamsters also received PEIT(50mM) in CO, on Tuesdays and Fridays. Three group 2 hamsters were similarly treated with the vehicle CO, and MBN in CO, during the 24 week experiment. At the completion of the experiment, whereas the group 2(unprotected) hamsters exhibited a total of 60 epithelial neoplasms(23 ± 10 tumors/hamster), including squamous cell carcinomas, a total of only 4 epithelial neoplasms were observed in the group 1(PEIT protected) hamsters pouches. In a follow-up experiment, PEIT(25mM) in CO also strongly inhibited MBN-mediated induction of microscopic epithelial cell foci exhibiting either gamma-glutamyl transpeptidase(GGT) histochemical activity or immunohistochemical staining for the p53 tumor suppressor gene product. These presumptive precancerous foci were identified in HBPE whole mounts prepared after 8 to 13 weeks of topical MBN(25mM) treatment. We conclude that PEIT is a potent inhibitor of MBN-mediated HBPE carcinogenesis, and that early GGT and p53 foci are predictive of chemoprevention in this experimental model of oral carcinogenesis.
|Original language||English (US)|
|Number of pages||1|
|Journal||Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontics|
|State||Published - Jan 1 1996|
ASJC Scopus subject areas
- Oral Surgery