title: Estrogens stimulate the proliferation of human cholangiocarcinoma by inducing the expression and secretion of vascular endothelial growth factor.
abstract: BACKGROUND
  Estrogens may induce the proliferation of neoplastic cells by activating neo-angiogenesis.
  
  
  OBJECTIVE
  To evaluate the effect of estrogens on the expression of vascular endothelial growth factor (VEGF) and related receptors (VEGF-R) in human cholangiocarcinoma and the role played by VEGF in mediating the proliferative effects of estrogens.
  
  
  METHODS
  Seven biopsies of intra-hepatic cholangiocarcinoma and the HuH-28 cell lines were investigated. Cell proliferation was measured by both PCNA Western blot and MTS proliferation assay.
  
  
  RESULTS
  By immunohistochemistry, biopsies of human cholangiocarcinoma stained positively for VEGF-A and VEGF-C and related receptors. HuH-28 cells expressed VEGF-A, -C, and VEGFR-1, -2, -3 and, their protein level was enhanced by 17beta-estradiol in association with the stimulation of cell proliferation. 17beta-Estradiol-stimulated proliferation of HuH-28 cells was blocked by 70% by VEGF-TRAP, a receptor-based VEGF inhibitor. 17beta-Estradiol induced the secretion of VEGF in the supernatant of HuH-28 cells. The stimulatory effect of 17beta-estradiol on the protein expression of VEGF-A, VEGF-C and VEGFR-1, -2, -3 was blocked by antagonists of ER (Ici182,780) or insulin-like growth factor 1-receptor (alphaIR3).
  
  
  CONCLUSIONS
  With the limitations of experiments performed in a cell line, our study indicates that VEGF plays a major role in mediating the proliferative effects of estrogens on human cholangiocarcinoma.
authors.affiliation: Department of Clinical Medicine, Division of Gastroenterology, University of Rome, La Sapienza, Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Mancino
authors.forename: M G
authors.initials: MG
authors.lastname: Mancino
authors.forename: S S
authors.initials: SS
authors.lastname: Glaser
authors.forename: G
authors.initials: G
authors.lastname: Alpini
authors.forename: A
authors.initials: A
authors.lastname: Bolognese
authors.forename: L
authors.initials: L
authors.lastname: Izzo
authors.forename: H
authors.initials: H
authors.lastname: Francis
authors.forename: P
authors.initials: P
authors.lastname: Onori
authors.forename: A
authors.initials: A
authors.lastname: Franchitto
authors.forename: S
authors.initials: S
authors.lastname: Ginanni-Corradini
authors.forename: E
authors.initials: E
authors.lastname: Gaudio
authors.forename: D
authors.initials: D
authors.lastname: Alvaro
mesh_terms: D000368:Aged; D001650:Bile Duct Neoplasms / Q000473:pathology / Q000503:physiopathology*; D001653:Bile Ducts, Intrahepatic / Q000187:drug effects / Q000503:physiopathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D018281:Cholangiocarcinoma / Q000473:pathology / Q000503:physiopathology*; D004958:Estradiol / Q000494:pharmacology*; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008297:Male; D040262:Receptors, Vascular Endothelial Growth Factor / Q000187:drug effects / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000187:drug effects* / Q000378:metabolism
chemical_list: D004967:Estrogens; D042461:Vascular Endothelial Growth Factor A; D004958:Estradiol; D040262:Receptors, Vascular Endothelial Growth Factor