TY - JOUR
T1 - Further characterization of skin tumor promotion and progession by mezerein in SENCAR mice
AU - Ewing, M. Winnann
AU - Conti, Claudio J.
AU - Phillips, James L.
AU - Slaga, Thomas J.
AU - Digiovanni, John
N1 - Funding Information:
Received December 16, 1988; revised February 6, 1989; accepted February 10, 1989. Supported by Public Health Service (PHS) grants CA-37111 (J. DiGio-vanni) and CA-43278 (T. J. Slaga) from the National Cancer Institute, National Institutes of Health, Department of Health and Human Services. M. W. Ewing was the recipient of PHS Postdoctoral Training Grant CA-09480 from the National Cancer Institute. TheUniversityofTexas,M.D.AndersonCancerCenter,Science Park-Research Division, Smithville, TX. We thank Joyce Mayhugh for assistance in preparing the manuscript and Dr. C. M. Aldaz for helpful discussions. * Correspondence to: Dr. John DiGiovanni, The University of Texas, M. D. Anderson Cancer Center, Science Park—Research Division, P.O. Box 389, Smithville, TX 78957.
PY - 1989/5/3
Y1 - 1989/5/3
N2 - This study evaluated the skin tumor-promoting activity of mezerein in SENCAR mice. The effect of initiation dose of 7, 12-dimethylbenz(α)anthracene (DMBA) on tumor promotion by mezerein was examined. Excellent dose-response relationships were observed for initiation with DMBA at 0.2-20 μg per mouse with mezerein as a complete promoter. None of the mezerein-only promotion groups had papilloma responses similar to those of the corresponding groups receiving two-stage promotion with 12-O-tetradecanoylphorbol-13-acetate (TPA) followed by mezerein, even when a 40-μg initiating dose of DMBA was used. The effect delaying promotion with mezerein for 10 weeks was also examined in mice initiated with either 0.2, 2, 20, or 40 μg of DMBA per mouse. The 10-week de-lay led to a slight increase in the number of papillomas per mouse in some but not all treatment groups. Again, none of the delayed-mezerein-treatment groups had papilloma responses similar to those of the corresponding two-stage pro-motion (TPA-mezerein) groups at any corresponding initiating dose of DMBA. Finally, the progression of papillomas to carcinomas during promotion with mezerein was examined in groups of mice initiated with either 2 or 20 μg of DMBA. Higher ratios of carcinomas to papillomas were observed in mice promoted with mezerein than in mice receiving TPA promotion or two-stage promotion (TPA-mezerein). However, the presence of two to four times more papillomas in some mezerein-treated groups did not lead to greater numbers of carcinomas than in the groups with fewer papillomas. The data do not support the idea that spontaneous stage I promotion can be induced by delaying mezerein treatment for 10 weeks. Furthermore, the data suggest that the higher ratio of carcinomas to papillomas observed with mezerein promotion may be a function of the lower tumor burdens obtained after promotion with this compound rather than a specific property of the chemical. [J Natl Can-cer Inst 81: 676-682, 1989]
AB - This study evaluated the skin tumor-promoting activity of mezerein in SENCAR mice. The effect of initiation dose of 7, 12-dimethylbenz(α)anthracene (DMBA) on tumor promotion by mezerein was examined. Excellent dose-response relationships were observed for initiation with DMBA at 0.2-20 μg per mouse with mezerein as a complete promoter. None of the mezerein-only promotion groups had papilloma responses similar to those of the corresponding groups receiving two-stage promotion with 12-O-tetradecanoylphorbol-13-acetate (TPA) followed by mezerein, even when a 40-μg initiating dose of DMBA was used. The effect delaying promotion with mezerein for 10 weeks was also examined in mice initiated with either 0.2, 2, 20, or 40 μg of DMBA per mouse. The 10-week de-lay led to a slight increase in the number of papillomas per mouse in some but not all treatment groups. Again, none of the delayed-mezerein-treatment groups had papilloma responses similar to those of the corresponding two-stage pro-motion (TPA-mezerein) groups at any corresponding initiating dose of DMBA. Finally, the progression of papillomas to carcinomas during promotion with mezerein was examined in groups of mice initiated with either 2 or 20 μg of DMBA. Higher ratios of carcinomas to papillomas were observed in mice promoted with mezerein than in mice receiving TPA promotion or two-stage promotion (TPA-mezerein). However, the presence of two to four times more papillomas in some mezerein-treated groups did not lead to greater numbers of carcinomas than in the groups with fewer papillomas. The data do not support the idea that spontaneous stage I promotion can be induced by delaying mezerein treatment for 10 weeks. Furthermore, the data suggest that the higher ratio of carcinomas to papillomas observed with mezerein promotion may be a function of the lower tumor burdens obtained after promotion with this compound rather than a specific property of the chemical. [J Natl Can-cer Inst 81: 676-682, 1989]
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U2 - 10.1093/jnci/81.9.676
DO - 10.1093/jnci/81.9.676
M3 - Article
C2 - 2496233
AN - SCOPUS:0024563992
VL - 81
SP - 676
EP - 682
JO - Journal of the National Cancer Institute
JF - Journal of the National Cancer Institute
SN - 0027-8874
IS - 9
ER -