title: Telomerase activity in human gliomas.
abstract: OBJECTIVE
  Telomerase activity, which is undetectable in most mature normal tissues, has been identified in many types of human cancers, including neuroblastomas and oligodendrogliomas. These findings suggest that a novel mechanism in addition to activation of oncogenes and inactivation of tumor suppressor genes may play an important role in tumorigenesis. The goal of the present study was to assess and correlate the telomerase activity in astrocytic gliomas of different grades.
  
  
  METHODS
  Telomere repeat amplification protocol and Southern blot hybridization with telomere-specific probes were used to detect telomerase activity and to measure terminal restriction fragment length, respectively.
  
  
  RESULTS
  Telomerase activity was detected in 3 of 9 (33%) low-grade astrocytomas (World Health Organization Grade II), 5 of 11 (45%) anaplastic astrocytomas (World Health Organization Grade III), 36 of 41 (89%) glioblastomas multiforme (World Health Organization Grade IV), 3 of 4 (75%) oligodendrogliomas, and none of 4 normal brain specimens.
  
  
  CONCLUSIONS
  We demonstrated that telomerase activity is absent in normal brain tissues while present in most glioma samples (72%). The frequency of such activity increases with malignancy. These results suggest that telomerase activity may be used as a tumor marker and that the activation of telomerase may correlate with initiation and malignant progression of astrocytic tumors.
authors.affiliation: Cold Spring Harbor Laboratory, New York, USA.
authors.forename: S
authors.initials: S
authors.lastname: Le
authors.forename: J J
authors.initials: JJ
authors.lastname: Zhu
authors.forename: D C
authors.initials: DC
authors.lastname: Anthony
authors.forename: C W
authors.initials: CW
authors.lastname: Greider
authors.forename: P M
authors.initials: PM
authors.lastname: Black
mesh_terms: D001254:Astrocytoma / Q000201:enzymology / Q000473:pathology; D001921:Brain / Q000201:enzymology*; D001932:Brain Neoplasms / Q000201:enzymology* / Q000473:pathology; D004273:DNA, Neoplasm / Q000032:analysis; D005909:Glioblastoma / Q000201:enzymology / Q000473:pathology; D005910:Glioma / Q000201:enzymology* / Q000473:pathology; D006801:Humans; D009363:Neoplasm Proteins / Q000032:analysis*; D009837:Oligodendroglioma / Q000201:enzymology / Q000473:pathology; D010865:Pilot Projects; D019098:Telomerase / Q000032:analysis*; D016615:Telomere / Q000737:chemistry
chemical_list: D004273:DNA, Neoplasm; D009363:Neoplasm Proteins; D019098:Telomerase