title: The association between telomerase activity and hormone receptor status and p53 expression in breast cancer.
abstract: BACKGROUND
  Telomerase is a ribonucleoprotein enzyme that seems to play an important role in cellular immortality and carcinogenesis. p53 mutations account for approximately 50% of human cancers and represent the most frequent genetic lesion in breast cancer.
  
  
  OBJECTIVE
  This study aims to examine the association between telomerase reactivation and hormonal receptor status and p53 expression in invasive breast cancer.
  
  
  METHODS
  Using a polymerase chain reaction-based assay, telomerase activity was determined in 47 invasive breast carcinomas and 21 adjacent non-cancerous breast tissue specimens (stored at -80 degrees C) prospectively collected from 47 women undergoing elective surgical treatment in our centre. The histopathological features of the tumour were determined by experienced breast pathologists using light microscopy and haematoxylin and eosin staining. Oestrogen receptor (ER), progesterone receptor (PR) and p53 expressions were determined using immunohistochemistry techniques.
  
  
  RESULTS
  Telomerase activity was detected in 34 (72%) of 47 breast carcinomas and in none of the adjacent non-cancerous breast specimens. There was a significant association between telomerase reactivation, tumour size and nodal status. Telomerase positive tumours were more likely to be poorly differentiated (65% versus 46%), but this association failed to reach statistical significance. There was no significant difference in ER expression (68% versus 85%). PR expression (62% versus 62%) and p53 expression (19% versus 27%) between telomerase positive and telomerase negative cancers.
  
  
  CONCLUSIONS
  Telomerase reactivation is associated with important prognostic factors such as tumour size and nodal status in invasive breast cancer and seems to be independent of hormonal receptor status and p53 expression.
authors.affiliation: St Bartholomew's Hospital, Smithfield, London, UK.
authors.forename: K
authors.initials: K
authors.lastname: Mokbel
authors.forename: M
authors.initials: M
authors.lastname: Ghilchik
authors.forename: G
authors.initials: G
authors.lastname: Williams
authors.forename: N
authors.initials: N
authors.lastname: Akbar
authors.forename: C
authors.initials: C
authors.lastname: Parris
authors.forename: R
authors.initials: R
authors.lastname: Newbold
mesh_terms: D001707:Biopsy, Needle; D001943:Breast Neoplasms / Q000737:chemistry*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D018807:Polymorphism, Single-Stranded Conformational; D011446:Prospective Studies; D011960:Receptors, Estrogen / Q000032:analysis*; D011980:Receptors, Progesterone / Q000032:analysis*; D019098:Telomerase / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000032:analysis*
chemical_list: D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D016159:Tumor Suppressor Protein p53; D019098:Telomerase