title: [Expression of pRb and E2F-1 and telomerase activity in ameloblastoma].
abstract: OBJECTIVE
  To investigate the expression of pRb and E2F-1, and the association between their expression and the activity of telomerase (hTERT) or cyclin E in human ameloblastoma (AB), and to explore the clinical biological characteristics of AB.
  
  
  METHODS
  The expressions of pRb, E2F-1, cyclin E and hTERT mRNA in human AB were detected by in situ hybridization or immunohistochemistry (SP method).
  
  
  RESULTS
  The positive expression ratio of pRb in the cell nucleus of AB was 20.4% (11/54). The positive ratio of E2F-1, cyclin E and hTERT mRNA was 92.6% (50/54), 66.7% (36/54) and 94.4% (51/54), respectively. With AB recurrence and malignant transformation, the expression of hTERT, E2F-1, cyclin E was up-regulated. hTERT and cyclin E or E2F-1 mRNA had high positive relation (Spearsman'r(s) = 1.000, P = 0.0001).
  
  
  CONCLUSIONS
  The regulatory pathway of Rb/E2F-1 is associated with the cell proliferation and in differentiation of AB. The activity or release of telomerase may be related to the lower expression of Rb and higher expression of E2F-1, and is up-regulated in G(1) late phase by cyclin E.
authors.affiliation: Department of Pathology, College of Stomatology, China Medical University, Shenyang 110002, China. zhongming1234@tom.com
authors.forename: Ming
authors.initials: M
authors.lastname: Zhong
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.forename: Lin
authors.initials: L
authors.lastname: Hou
authors.forename: Yang-li
authors.initials: YL
authors.lastname: Yue
authors.forename: Zi-juan
authors.initials: ZJ
authors.lastname: Li
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000564:Ameloblastoma / Q000378:metabolism* / Q000473:pathology; D002648:Child; D019927:Cyclin E / Q000096:biosynthesis; D050687:E2F1 Transcription Factor / Q000096:biosynthesis*; D005260:Female; D006801:Humans; D007573:Jaw Neoplasms / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000096:biosynthesis; D016160:Retinoblastoma Protein / Q000096:biosynthesis*; D019098:Telomerase / Q000235:genetics / Q000378:metabolism*
chemical_list: D019927:Cyclin E; D050687:E2F1 Transcription Factor; D012333:RNA, Messenger; D016160:Retinoblastoma Protein; D019098:Telomerase