title: Correlation of P-glycoprotein expression with poor vascularization in human gallbladder carcinomas.
abstract: OBJECTIVE
  To investigate the relationship between the expression of P-glycoprotein (P-gp) and the degree of vascularization in gallbladder carcinomas.
  
  
  METHODS
  P-gp was stained with streptavidin-peroxidase complex immunohistochemical method in routine paraffin-embedded sections of gallbladder carcinomas. Microvessel counts (MVC) were determined using factor-VIII-related antigens.
  
  
  RESULTS
  The average MVC in 32 cases of gallbladder carcinomas was (34 +/- 10)/HP. The value of MVC was closely correlated with Nevin staging and tumor differentiation (P<0.01 and P<0.05). The total expression rate of P-gp was 62.5%. The P-gp expression rate in cases of Nevin staging S1-S3 (78.6%) was higher than that of S4-S5 (50.0%) with no statistical significance. The P-gp expression rate was not correlated with tumor differentiation or pathologic types. The value of MVC in P-gp (+) cases was markedly lower than that in P-gp (-) cases (P<0.01). The positive rate of P-gp was significantly higher in cases of smaller MVC than those of bigger MVC (P<0.05).
  
  
  CONCLUSIONS
  MVC may be used as one of the important parameters to reflect the biological behaviors of gallbladder carcinomas. As a major cause of drug resistance, the overexpression of P-gp is closely correlated with the poor vascularization in gallbladder carcinomas.
authors.affiliation: Department of General Surgery, First Affiliated Hospital, China Medical University, Shenyang 110001, Liaoning Province, China. tianyu5460@21cn.com
authors.forename: Yu
authors.initials: Y
authors.lastname: Tian
authors.forename: Li-Li
authors.initials: LL
authors.lastname: Zhu
authors.forename: Ren-Xuan
authors.initials: RX
authors.lastname: Guo
authors.forename: Chui-Feng
authors.initials: CF
authors.lastname: Fan
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics*; D005260:Female; D005706:Gallbladder Neoplasms / Q000098:blood supply* / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D016896:Treatment Outcome
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1