title: Widespread expression of prostate apoptosis response-4 in nasopharyngeal carcinoma.
abstract: BACKGROUND
  Prostate apoptosis response-4 (Par-4) augments apoptosis in various tumors, either during apoptotic insult or by ectopic overexpression. However, investigation of Par-4 expression in nasopharyngeal carcinoma (NPC) is lacking.
  
  
  METHODS
  Specimens from patients with NPC, hypopharyngeal carcinoma (HPC), or oral cavity cancer were examined for Par-4 expression using immunohistochemistry. NPC cell proliferation and apoptosis were analyzed using immunohistochemical staining for Ki67, B-cell lymphoma 2 (Bcl-2), and in situ terminal deoxyribonucleotidyl transferase (TdT)-mediated biotin-16-dUTP nick end-labeling (TUNEL) assay, respectively.
  
  
  RESULTS
  Par-4 was ubiquitously expressed in NPC biopsies (96.2%, 25/26) and was significantly higher than in HPC (47.6%, 50/105, p < .0001) and oral cavity cancers (38.7%, 12/31, p < .0001). Remarkably, apoptosis of NPC cells was absent and Par-4 expression was associated with obvious expression of Bcl-2 and Ki67 in all patients tested with NPC.
  
  
  CONCLUSIONS
  Immunohistochemistry results showed widespread expression of Par-4 in NPC and revealed sustainable proliferation of NPC cells regardless of Par-4 expression.
authors.affiliation: Institute of Life Science, College of Life Science, Tzu-Chi University, Hualien, Taiwan. jwlee@mail.tcu.edu.tw
authors.forename: Jeng-Woei
authors.initials: JW
authors.lastname: Lee
authors.forename: Wei-Ting
authors.initials: WT
authors.lastname: Hsiao
authors.forename: Kuei-Fang
authors.initials: KF
authors.lastname: Lee
authors.forename: Lai-Fa
authors.initials: LF
authors.lastname: Sheu
authors.forename: Hsue-Yin
authors.initials: HY
authors.lastname: Hsu
authors.forename: Lee-Ping
authors.initials: LP
authors.lastname: Hsu
authors.forename: Borcherng
authors.initials: B
authors.lastname: Su
authors.forename: Moon-Sing
authors.initials: MS
authors.lastname: Lee
authors.forename: Yih-Chih
authors.initials: YC
authors.lastname: Hsu
authors.forename: Chung-Hsing
authors.initials: CH
authors.lastname: Chang
mesh_terms: D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism*; D002277:Carcinoma / Q000378:metabolism* / Q000473:pathology*; D049109:Cell Proliferation; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007012:Hypopharyngeal Neoplasms / Q000378:metabolism / Q000473:pathology; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D009062:Mouth Neoplasms / Q000378:metabolism / Q000473:pathology; D009303:Nasopharyngeal Neoplasms / Q000378:metabolism* / Q000473:pathology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism
chemical_list: D051017:Apoptosis Regulatory Proteins; D019394:Ki-67 Antigen; D019253:Proto-Oncogene Proteins c-bcl-2; C101296:prostate apoptosis response-4 protein