title: GADD153 mediates celecoxib-induced apoptosis in cervical cancer cells.
abstract: Celecoxib, a selective cyclooxygenase 2 inhibitor, is known to have anti-inflammatory activity and to induce apoptosis in various types of cancer cells. Here, we examined the molecular mechanism of celecoxib-induced apoptosis in cervical cancer cell lines (HeLa, CaSki and C33A). Screening of a microarray cDNA-chip containing 225 different genes revealed that growth arrest and DNA damage inducible gene (GADD153), a transcription factor involved in apoptosis, showed the strongest differential expression following celecoxib treatment in all three cervical cancer cell lines. Notably, siRNA-induced silencing of GADD153 suppressed celecoxib-induced apoptosis in all the three cell lines, and exogenous expression of GADD153 triggered apoptosis in cervical cancer cells in the absence of other apoptotic stimuli. A luciferase reporter gene assay and mRNA stability tests revealed that expression of GADD153 was regulated at both the transcriptional and post-transcriptional levels following celecoxib treatment. The region between -649 and -249, containing an intact C/EBP-ATF binding site, was required for the basal activity and celecoxib-induced stimulation of GADD153 promoter activity. Also, mRNA stability test showed that celecoxib prolonged the half-life of GADD153 mRNA. In terms of signaling pathway, addition of the NF-kappaB inhibitor, N-tosyl-L phenylalanyl-chloromethyl ketone (TPCK), had no effect on GADD153 expression levels. Celecoxib treatment induced Bak expression, whereas cell treated with siGADD153 or TPCK showed lower levels of celecoxib-induced Bak up-regulation. These novel findings collectively suggest that GADD153 may play a key role in celecoxib-induced apoptosis in cervical cancer cells by regulating the expression of proapoptotic proteins such as Bak.
authors.affiliation: Cancer Research Institute, Seoul National University College of Medicine, 28 Yungun-Dong, Chongno-Ku, Seoul 110-744, Korea.
authors.forename: Su-Hyeong
authors.initials: SH
authors.lastname: Kim
authors.forename: Chang-Il
authors.initials: CI
authors.lastname: Hwang
authors.forename: Yong-Sung
authors.initials: YS
authors.lastname: Juhnn
authors.forename: Je-Ho
authors.initials: JH
authors.lastname: Lee
authors.forename: Woong-Yang
authors.initials: WY
authors.lastname: Park
authors.forename: Yong-Sang
authors.initials: YS
authors.lastname: Song
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D000068579:Celecoxib; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D005260:Female; D005434:Flow Cytometry; D006367:HeLa Cells / Q000187:drug effects; D006801:Humans; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011720:Pyrazoles / Q000494:pharmacology*; D020871:RNA Stability / Q000187:drug effects; D012333:RNA, Messenger / Q000032:analysis; D034741:RNA, Small Interfering / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D013449:Sulfonamides / Q000494:pharmacology*; D051742:Transcription Factor CHOP / Q000235:genetics / Q000378:metabolism*; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D050998:bcl-2 Homologous Antagonist-Killer Protein / Q000378:metabolism
chemical_list: C494772:BAK1 protein, human; D016861:Cyclooxygenase Inhibitors; C497249:DDIT3 protein, human; D016328:NF-kappa B; D011720:Pyrazoles; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D013449:Sulfonamides; D050998:bcl-2 Homologous Antagonist-Killer Protein; D051742:Transcription Factor CHOP; D000068579:Celecoxib