title: Antiproliferative effects of celecoxib in Hep-2 cells through telomerase inhibition and induction of apoptosis.
abstract: BACKGROUND
  To investigate the effect of celecoxib on telomerase activity and apoptosis in a human laryngeal squamous carcinoma cell line (Hep-2 cells).
  
  
  METHODS
  The growth inhibition rate of Hep-2 cells in vitro was measured by MTT assay, and apoptosis by TUNEL assay and flow cytometry (FCM). The TRAP-ELISA method was used to determine telomerase activity in Hep-2 cells. The mRNA expression of human telomerase RNA component(hTR), human telomerase reverse transcriptase (hTERT) and human telomerase-associated protein(hTEP1) was determined by RT-PCR assay. Expression of Bax and Bcl-2 proteins was assessed by Western blotting.
  
  
  RESULTS
  Celecoxib can inhibit proliferation and induce apoptosis in a dose- and time-dependent manner, repress telomerase activity, decrease hTERT mRNA and Bcl-2 protein expression and increase Bax protein expression, PGE2 had no effect on telomerase.
  
  
  CONCLUSIONS
  Celecoxib had the antiproliferative and pro-apoptotic effect in Hep-2 cells. Apoptosis was accompanied by a decrease in telomerase activity which was directly correlated with hTERT mRNA and up-regulation of Bax/Bcl-2. Bcl-2 may thus play an important role in telomerase activity as well as apoptosis.
authors.affiliation: Department of Otolaryngology and Head and Neck Surgery, the Second Hospital of Shandong University, Jinan, China E-mail : sdentfan@126.com.
authors.forename: Yong-Qiang
authors.initials: YQ
authors.lastname: Zhao
authors.forename: Hui-Wei
authors.initials: HW
authors.lastname: Feng
authors.forename: Tao
authors.initials: T
authors.lastname: Jia
authors.forename: Xue-Mei
authors.initials: XM
authors.lastname: Chen
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.forename: An-Ting
authors.initials: AT
authors.lastname: Xu
authors.forename: Hai-Ling
authors.initials: HL
authors.lastname: Zhang
authors.forename: Xian-Liang
authors.initials: XL
authors.lastname: Fan
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D000068579:Celecoxib; D049109:Cell Proliferation / Q000187:drug effects*; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology*; D005434:Flow Cytometry; D006801:Humans; D007124:Immunoenzyme Techniques; D007822:Laryngeal Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D011720:Pyrazoles / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013449:Sulfonamides / Q000494:pharmacology*; D019098:Telomerase / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: D052246:Cyclooxygenase 2 Inhibitors; D011720:Pyrazoles; D012333:RNA, Messenger; D013449:Sulfonamides; C509186:TERT protein, human; D019098:Telomerase; D000068579:Celecoxib