title: Expression of CD44V6 in parotid pleomorphic adenoma and carcinoma ex pleomorphic adenoma.
abstract: BACKGROUND
  Change in expression of CD44 variant (CD44v) has been observed in several types of aggressive carcinomas. This pattern of expression might be associated with carcinogenesis of parotid pleomorphic adenoma (PPA) which is not widely studied. In this study, we aimed to investigate the expression of CD44v6 in the PPA before and after recurrence, between non-recurrent PPA, recurrent PPA, and PPA with carcinogenesis so as to identify whether the expression differences have existed before the recurrence and its significance for predicting the recurrence.
  
  
  METHODS
  Expression differences of CD44v6 were detected by immunohistochemistry in samples of non-recurrent PPA, PPA before and after the recurrence, carcinoma in pleomorphic adenoma (CPA) and normal parotid.
  
  
  RESULTS
  The expression of CD44v6 was significantly higher in the group before the recurrence than that after the recurrence (p < 0.05). The expression of CD44v6 after recurrence was significantly lower than that in the non-recurrent group (p < 0.05) while the high level of CD44v6 expression in the non-recurrent group, was significantly lower than in the group with CPA (p < 0.05). However, no significant difference was observed between the group after recurrence and CPA.
  
  
  CONCLUSIONS
  The decrease of CD44v6 expression promoted the recurrence and carcinogenesis of PPA, and the expression was decreased further in the process. The expression differences of CD44v6 had appeared before the recurrence.
authors.affiliation: Sichuan University, China.
authors.forename: Sen
authors.initials: S
authors.lastname: Yang
authors.forename: Hong-Ping
authors.initials: HP
authors.lastname: Wang
authors.forename: Xiao-Yi
authors.initials: XY
authors.lastname: Wang
authors.forename: Li-Juan
authors.initials: LJ
authors.lastname: Guo
authors.forename: Xiu-Fa
authors.initials: XF
authors.lastname: Tang
authors.forename: Qi-Hong
authors.initials: QH
authors.lastname: Gao
authors.forename: Ming
authors.initials: M
authors.lastname: Xuan
authors.forename: Wings T Y
authors.initials: WT
authors.lastname: Loo
authors.forename: Louis W C
authors.initials: LW
authors.lastname: Chow
mesh_terms: D008949:Adenoma, Pleomorphic / Q000235:genetics* / Q000473:pathology; D000293:Adolescent; D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000235:genetics / Q000473:pathology; D002648:Child; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D006801:Humans; D018960:Hyaluronan Receptors / Q000235:genetics*; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D010307:Parotid Neoplasms / Q000235:genetics* / Q000473:pathology; D055815:Young Adult
chemical_list: C112697:CD44v6 antigen; D018960:Hyaluronan Receptors