title: Correlation of dyskerin expression with active proliferation independent of telomerase.
abstract: BACKGROUND
  Dyskerin, which is an important component of the telomerase complex and is needed for normal telomerase activity, is frequently overexpressed in neoplasia. Dyskerin also plays an essential role in ribosome biogenesis. Because protein synthesis increases during tumorigenesis, this led us to hypothesize that dyskerin expression would be upregulated independently of the cell immortalization mechanism.
  
  
  METHODS
  Dyskerin and telomerase reverse transcriptase (TERT) expression were examined in oral squamous cell carcinomas (OSCC) and patient-matched controls, as well as in a panel of telomerase-positive and telomerase-negative cells. Antisense inhibition of TERT was used to test the effects of downregulation of telomerase on dyskerin expression.
  
  
  RESULTS
  Dyskerin was frequently overexpressed in OSCC and in immortalized and transformed keratinocytes relative to primary cells, independently of TERT and telomerase activity. Instead, dyskerin expression strongly correlated with cell proliferation rates.
  
  
  CONCLUSIONS
  The role of dyskerin in tumorigenesis does not correlate with its function within the telomerase complex.
authors.affiliation: Department of Pathology, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania. falawi@upenn.edu
authors.forename: Faizan
authors.initials: F
authors.lastname: Alawi
authors.forename: Ping
authors.initials: P
authors.lastname: Lin
authors.forename: Barry
authors.initials: B
authors.lastname: Ziober
authors.forename: Reena
authors.initials: R
authors.lastname: Patel
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000378:metabolism*; D049109:Cell Proliferation; D002478:Cells, Cultured; D004252:DNA Mutational Analysis; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology*; D018095:Germ-Line Mutation; D006258:Head and Neck Neoplasms / Q000378:metabolism*; D006801:Humans; D015603:Keratinocytes / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism*; D016376:Oligonucleotides, Antisense; D000077195:Squamous Cell Carcinoma of Head and Neck; D019098:Telomerase / Q000378:metabolism*; D015854:Up-Regulation / Q000502:physiology
chemical_list: D018797:Cell Cycle Proteins; C112148:DKC1 protein, human; D009687:Nuclear Proteins; D016376:Oligonucleotides, Antisense; D019098:Telomerase