title: Ultraviolet C irradiation induces different expression of cyclooxygenase 2 in NIH 3T3 cells and A431 cells: the roles of COX-2 are different in various cell lines.
abstract: Ultraviolet C (UVC) is a DNA damage inducer, and 20 J/m(2) of UVC irradiation caused cell growth inhibition and induced cell death after exposure for 24-36 h. The growth of NIH 3T3 cells was significantly suppressed at 24 h after UVC irradiation whereas the proliferation of A431 cells was inhibited until 36 h after UVC irradiation. UVC irradiation increased COX-2 expression and such up-regulation reached a maximum during 3-6 h in NIH 3T3 cells. In contrast, UVC-induced COX-2 reached a maximum after 24-36 h in A431 cells. Measuring prostaglandin E2 (PGE2) level showed a biphasic profile that PGE2 release was rapidly elevated in 1-12 h after UVC irradiation and increased again at 24 h in both cell lines. Treatment with the selective COX-2 inhibitor, SC-791, during maximum expression of COX-2 induction, attenuated the UVC induced-growth inhibition in NIH 3T3 cells. In contrast, SC-791 treatment after UVC irradiation enhanced death of A431 cells. These data showed that the patterns of UVC-induced PGE2 secretion from NIH 3T3 cells and A431 cells were similar despite the differential profile in UVC-induced COX-2 up-regulation. Besides, COX-2 might play different roles in cellular response to UVC irradiation in various cell lines.
authors.affiliation: Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan.
authors.forename: Ming-Hong
authors.initials: MH
authors.lastname: Tai
authors.affiliation: Department of Biological Sciences, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan.
authors.forename: Chien-Hui
authors.initials: CH
authors.lastname: Weng
authors.affiliation: Department of Nutrition and Health Science, Fooyin University, Kaohsiung 83102, Taiwan.
authors.forename: Dir-Pu
authors.initials: DP
authors.lastname: Mon
authors.affiliation: Department of Nutrition and Health Science, Fooyin University, Kaohsiung 83102, Taiwan.|Research Center of Health Food, Fooyin University, Kaohsiung 83102, Taiwan.
authors.forename: Chun-Yi
authors.initials: CY
authors.lastname: Hu
authors.affiliation: Department of Nutrition and Health Science, Fooyin University, Kaohsiung 83102, Taiwan.|Research Center of Health Food, Fooyin University, Kaohsiung 83102, Taiwan.
authors.forename: Ming-Hsiu
authors.initials: MH
authors.lastname: Wu
mesh_terms: D016475:3T3 Cells; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects / Q000528:radiation effects; D051546:Cyclooxygenase 2 / Q000096:biosynthesis*; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology; D015232:Dinoprostone / Q000096:biosynthesis* / Q000378:metabolism; D006801:Humans; D007555:Isoxazoles / Q000494:pharmacology*; D051379:Mice; D013449:Sulfonamides / Q000494:pharmacology*; D014466:Ultraviolet Rays / Q000009:adverse effects*; D015854:Up-Regulation / Q000528:radiation effects
chemical_list: D052246:Cyclooxygenase 2 Inhibitors; D007555:Isoxazoles; C553330:SC 791; D013449:Sulfonamides; D051546:Cyclooxygenase 2; D015232:Dinoprostone