BACKGROUND: Estrogens may induce the proliferation of neoplastic cells by activating neo-angiogenesis. AIM: 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.
BACKGROUND: Estrogens may induce the proliferation of neoplastic cells by activating neo-angiogenesis. AIM: To evaluate the effect of estrogens on the expression of vascular endothelial growth factor (VEGF) and related receptors (VEGF-R) in humancholangiocarcinoma 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 humancholangiocarcinoma 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 humancholangiocarcinoma.
Authors: A Migliaccio; G Castoria; M Di Domenico; A de Falco; A Bilancio; M Lombardi; D Bottero; L Varricchio; M Nanayakkara; A Rotondi; F Auricchio Journal: J Steroid Biochem Mol Biol Date: 2002-12 Impact factor: 4.292