First Author | Cooper SJ | Year | 2003 |
Journal | Mol Cancer Res | Volume | 1 |
Issue | 11 | Pages | 848-54 |
PubMed ID | 14517347 | Mgi Jnum | J:85672 |
Mgi Id | MGI:2675930 | Citation | Cooper SJ, et al. (2003) Expression of Dominant Negative c-jun Inhibits Ultraviolet B-Induced Squamous Cell Carcinoma Number and Size in an SKH-1 Hairless Mouse Model. Mol Cancer Res 1(11):848-54 |
abstractText | UVB radiation is a complete carcinogen able to initiate, promote, and progress keratinocyte cells toward carcinogenesis. Exposure to UVB leads to the propagation of a number of signal transduction pathways resulting in increased DNA binding of transcription factors, including activator protein-1 (AP-1), and subsequent gene expression. To test the hypothesis that AP-1 activation plays a role in the promotion of UVB-induced skin tumors, a dominant negative c-jun (TAM67) mutant transgene was expressed in the epidermis of SKH-1 hairless mice and bred with mice expressing an AP-1 luciferase reporter gene. Single UVB exposure experiments showed a significant decrease in AP-1 activity, as measured by luciferase levels, in mice expressing TAM67 72 h postexposure. Transgenic and nontransgenic littermates were placed into a chronic UVB exposure experiment, three exposures per week for 25 weeks. Expression of TAM67 reduced the number of tumors per mouse by 58% and tumor sizes were 79% smaller than the tumors present in the nontransgenic study group. These tumors were histologically identified as squamous cell carcinomas. TAM67 had no effect on UVB-induced hyperplasia because comparable epidermal thickening was observed in both study groups over a 5-day period post-UVB exposure. Immunohistochemical analysis showed a reduction in the number of cyclin D(1)-expressing cells in squamous cell carcinoma samples removed from the TAM67 study group. These data show that TAM67 can inhibit UVB-induced squamous cell carcinoma formation, suggesting that AP-1 is a good candidate target for the development of new chemoprevention strategies to prevent sunlight-induced skin cancers. |