title: The association between telomerase, histopathological parameters, and KI-67 expression in breast cancer.
abstract: BACKGROUND
  Telomerase is a ribonucleoprotein enzyme that appears to play an important role in carcinogenesis. Telomerase reactivation seems to be associated with immortalization and malignancy.
  
  
  METHODS
  Using a polymerase chain reaction (PCR)-based assay known as the TRAP (telomeric repeat and amplification protocol) assay, we examined telomerase activity in 60 breast specimens prospectively collected from 39 patients undergoing elective breast surgery in our center. The specimens included adjacent noncancerous breast (n = 21), benign breast disease (n = 5), and infiltrating carcinoma (n = 34). Ki-67 expression was determined in 32 invasive breast cancer specimens using immunohistochemistry techniques. The histopathological features were determined by light microscopy by an experienced breast pathologist.
  
  
  RESULTS
  Telomerase activity was detected in 24 (71%) of 34 infiltrating carcinomas. None of the adjacent noncancerous specimens nor the benign breast lesions expressed telomerase activity. Telomerase reactivation was significantly associated with nodal metastasis and Ki-67 expression. There was no significant association between telomerase activity and menopausal status, tumor grade, or tumor size.
  
  
  CONCLUSIONS
  Telomerase reactivation is associated with the acquisition of malignancy in the human breast. Telomerase activity is significantly associated with nodal metastasis and cellular proliferation as measured by Ki-67 expression in human breast cancer.
authors.affiliation: Imperial College, London, UK.
authors.forename: K
authors.initials: K
authors.lastname: Mokbel
authors.forename: C N
authors.initials: CN
authors.lastname: Parris
authors.forename: M
authors.initials: M
authors.lastname: Ghilchik
authors.forename: G
authors.initials: G
authors.lastname: Williams
authors.forename: R F
authors.initials: RF
authors.lastname: Newbold
mesh_terms: D000328:Adult; D000595:Amino Acid Sequence; D001943:Breast Neoplasms / Q000235:genetics / Q000473:pathology / Q000503:physiopathology*; D018270:Carcinoma, Ductal, Breast / Q000235:genetics / Q000503:physiopathology* / Q000556:secondary; D002471:Cell Transformation, Neoplastic; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000096:biosynthesis* / Q000235:genetics; D008207:Lymphatic Metastasis; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011379:Prognosis; D011446:Prospective Studies; D019098:Telomerase / Q000378:metabolism*
chemical_list: D019394:Ki-67 Antigen; D019098:Telomerase