title: Expression of telomerase genes in cancer development in atypical hyperplasia of the mammary duct.
abstract: OBJECTIVE
  To investigate telomerase gene expression in precancerous mammary lesion, such as atypical ductal hyperplasia and breast cancer and to study the relationship between expression and malignant transformation.
  
  
  METHODS
  Expression of human telomerase genes (hTR) and human reverse transcriptase gene (hTRT) in 76 cases of mammary tissue was evaluated using in situ hybridization and included 50 cases of mammary hyperplasia, 6 of which were benign hyperplasia, 9 were mild atypical hyperplasia, 12 were moderate atypical hyperplasia, 23 were severe atypical hyperplasia and 26 were mammary cancer.
  
  
  RESULTS
  The expressions of hTR and hTRT mRNA were much weaker or negative in benign hyperplasia (16.6%, 0), weak to mild  moderate in atypical hyperplasia (22.2%, 11.1%, 33.3%, 25.0%), strong in severe atypical hyperplasia (60.9%, 52.1%), and significantly strong in mammary cancer (88.5%, 80.8%). The difference between mild-moderate atypical hyperplasia, invasive ductal carcinoma and severe atypical hyperplasia was significant (P < 0.05) and the difference between severe atypical hyperplasia and intraductal carcinoma was not significant (P > 0.05).
  
  
  CONCLUSIONS
  Telomerase genes (hTR and hTRT) expressions are related to the transformation of atypical hyperplasia. Activated telomerase may play a role in mammary cancer development.
authors.affiliation: Department of Pathology, College of Basic Medical Sciences, China Medical University, Shenyang 110001, China.
authors.forename: Min
authors.initials: M
authors.lastname: Song
authors.forename: Xiaoyi
authors.initials: X
authors.lastname: Mi
authors.forename: Bailin
authors.initials: B
authors.lastname: Li
authors.forename: Jijiang
authors.initials: J
authors.lastname: Zhu
authors.forename: Yingxian
authors.initials: Y
authors.lastname: Gao
authors.forename: Shuang
authors.initials: S
authors.lastname: Cui
authors.forename: Jiye
authors.initials: J
authors.lastname: Song
mesh_terms: D001940:Breast / Q000378:metabolism / Q000473:pathology; D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology; D004268:DNA-Binding Proteins; D005260:Female; D015870:Gene Expression; D006801:Humans; D011230:Precancerous Conditions / Q000235:genetics* / Q000473:pathology; D012313:RNA / Q000235:genetics* / Q000502:physiology; D012333:RNA, Messenger / Q000032:analysis; D019098:Telomerase / Q000235:genetics* / Q000502:physiology
chemical_list: D004268:DNA-Binding Proteins; D012333:RNA, Messenger; C422952:telomerase RNA; D012313:RNA; D019098:Telomerase