title: [Telomerase activity in uveal melanomas].
abstract: BACKGROUND
  The maximum number of cell divisions of a certain cell population is genetically fixed so that aging cells become non-dividing (senescent) at least. This replicative life span, also known as "Hayflick limit", is probably defined by a "critical" length of the telomeres. Telomeres are special DNA-sequences located at the four ends of the chromosomes which are shortened with each cell cycle. Cells of most, but not all malignant tumours have been shown to reactivate the enzyme telomerase so that telomeres can be reconstructed, "Hayflick limit" can be overcome, and unlimited cell division can be established. This study was undertaken to elucidate whether telomerase reactivation is used by uveal melanoma cells.
  
  
  METHODS
  Fresh tumour tissue was removed from 10 untreated uveal melanomas after enucleation. Telomerase activity was determined using a PCR ELISA according to the Telomeric Repeat Amplification Protocol (TRAP). Normal tissue of the skin and the conjunctiva served as control.
  
  
  RESULTS
  Telomerase activity was detectable in 90% of the investigated uveal melanomas. All control specimens were telomerase negative.
  
  
  CONCLUSIONS
  Uveal melanoma growth seems to depend on telomerase reactivation. Thus, telomerase inhibition could offer a new principle for uveal melanoma therapy in the future.
authors.affiliation: Abt. I, Universitäts-Augenklinik Tübingen.
authors.forename: J M
authors.initials: JM
authors.lastname: Rohrbach
authors.forename: C
authors.initials: C
authors.lastname: Riedinger
authors.forename: M
authors.initials: M
authors.lastname: Wild
authors.forename: M
authors.initials: M
authors.lastname: Partsch
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002455:Cell Division / Q000502:physiology*; D016922:Cellular Senescence / Q000502:physiology*; D004789:Enzyme Activation / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008545:Melanoma / Q000503:physiopathology*; D008875:Middle Aged; D019098:Telomerase / Q000378:metabolism*; D016615:Telomere / Q000502:physiology; D014604:Uveal Neoplasms / Q000503:physiopathology*
chemical_list: D019098:Telomerase