| First Author | Fischer SM | Year | 2007 |
| Journal | Mol Carcinog | Volume | 46 |
| Issue | 5 | Pages | 363-71 |
| PubMed ID | 17219415 | Mgi Jnum | J:121635 |
| Mgi Id | MGI:3710751 | Doi | 10.1002/mc.20284 |
| Citation | Fischer SM, et al. (2007) Cyclooxygenase-2 expression is critical for chronic UV-induced murine skin carcinogenesis. Mol Carcinog 46(5):363-71 |
| abstractText | While it has been established that both the constitutive and inducible forms of cyclooxygenase (COX-1 and COX-2, respectively) play important roles in chemical initiation-promotion protocols with phorbol ester tumor promoters, the contribution of these two enzymes to ultraviolet (UV) light-induced skin tumors has not been fully assessed. To better understand the contribution of COX-1 and COX-2 to UV carcinogenesis, we transferred the null allele for each isoform onto the SKH-1 hairless strain of mouse. Due to low viability on this background with complete knockout of COX-2, heterozygous mice were used in UV carcinogenesis experiments. While the lack of one allele of COX-1 had no effect on tumor outcome, the lack of one allele of COX-2 resulted in a 50-65% reduction in tumor multiplicity and a marked decrease in tumor size. Additionally, transgenic SKH-1 mice that overexpress COX-2 under the control of a keratin 14 promoter developed 70% more tumors than wild-type SKH-1 mice. The lack of one allele of either COX-1 or COX-2 reduced prostaglandin (PG) E2 levels in response to a single UV treatment. The proliferative response to UV was significantly reduced in COX-2, but not COX-1, heterozygous mice. UV-induced apoptosis, however, was greater in COX-2 heterozygous mice. Collectively, these results clearly establish the requirement for COX-2 in the development of skin tumors. |
