Malignant progression of mouse skin papillomas treated with ethylnitrosourea, N-methyl-N'-nitro-N-nitrosoguanidine, or 12-O-tetradecanoylphorbol-13-acetate
Autor: | Thomas J. Slaga, John F. O'Connell, J. W. Fries, D. M. Digiovanni, A.J.P. Klein-Szanto |
---|---|
Rok vydání: | 1986 |
Předmět: |
Cancer Research
Pathology medicine.medical_specialty Methylnitronitrosoguanidine Skin Neoplasms Ratón 9 10-Dimethyl-1 2-benzanthracene DMBA 12-O-Tetradecanoylphorbol-13-acetate medicine.disease_cause Malignant transformation chemistry.chemical_compound Mice medicine Potency Animals integumentary system Papilloma business.industry gamma-Glutamyltransferase Oncology chemistry Nitrosamine Ethylnitrosourea Cancer research Tetradecanoylphorbol Acetate Female business Carcinogenesis |
Zdroj: | Cancer letters. 30(3) |
ISSN: | 0304-3835 |
Popis: | Mouse skin tumors were induced by a single topical application of 7,12-dimethylbenzanthracene (DMBA), followed by biweekly promotion with 12- O -tetradecanoylphorbol-13-acetate (TPA). After 20 weeks of promotion, mice were treated twice weekly for 2 weeks with either ethylnitrosourea (ENU), N -methyl- N′ -nitro- N -nitrosoguanidine (MNNG) or TPA. Thereafter all groups were treated biweekly with TPA. The ENU-treated group had a higher percentage of animals with carcinomas and developed 217% more cumulative carcinomas per group than TPA-treated controls. The percentage of mice with carcinomas and the cumulative number of carcinomas per group in MNNG-treated mice was higher than TPA-treated controls but was less than ENU-treated mice. The ratio of cumulative carcinomas to cumulative papillomas in ENU treated, MNNG-treated and TPA-treated mice was 16%, 9% and 6%, respectively. Histological examination of tumors remaining at the termination of the experiment revealed the presence of keratoacanthomas, some of which stained positive for γ-glutamyltransferase (GGT), in the ENU-treated and MNNG-treated, but not the TPA-treated groups. The fact that no new papillomas developed during the progression stage indicated that enhanced carcinogenesis resulted from the progression of pre-existing tumors. Enhanced progression of benign skin tumors in mice by only a few treatments of an agent may serve as a potential model for studies into the mechanisms and the inhibition of malignant progression. The model also allows for a comparison of the potency of agents in enhancing malignant progression. |
Databáze: | OpenAIRE |
Externí odkaz: |