Inhibition of hamster buccal pouch carcinogenesis by 13-cis-retinoic acid.
Sixty-four male and female Syrian hamsters, 3 months of age and weighing 90 to 120 grams, were divided into four equal experimental groups. In animals of Groups 1 and 2 the left buccal pouch was painted three times weekly with a 0.5% solution of DMBA in heavy mineral oil. Group 2 animals also received 10 mg. of 13-cis-retinoic acid in peanut oil administered orally twice a week by pipette. Carcinogen retinoid were administered on alternate days. Group 3 animals served as controls, receiving only 13-cis-retinoic acid. Group 4 animals served as untreated controls. Four animals in each group (two males and two females) were killed at 10, 12, 14, and 16 weeks. The Group 2 animals, which received 13-cis-retinoic acid, exhibited a significant delay in DMBA carcinogenesis of buccal pouch mucosa, as studied both grossly and histologically. Both groups eventually demonstrated well-differentiated epidermoid carcinomas, but the tumors were smaller in the DMBA-retinoid animals.
D000818:Animals; D002291:Carcinoma, Papillary / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000473:pathology; D002610:Cheek; D006224:Cricetinae; D005260:Female; D015474:Isotretinoin; D007642:Keratosis / Q000473:pathology; D007972:Leukoplakia, Oral / Q000473:pathology; D008297:Male; D008647:Mesocricetus; D009061:Mouth Mucosa / Q000473:pathology; D009062:Mouth Neoplasms / Q000473:pathology / Q000517:prevention & control*; D009374:Neoplasms, Experimental / Q000473:pathology / Q000517:prevention & control*; D014212:Tretinoin / Q000627:therapeutic use*
D014212:Tretinoin; D015474:Isotretinoin