title: z-Guggulsterone, a constituent of Ayurvedic medicinal plant Commiphora mukul, inhibits angiogenesis in vitro and in vivo.
abstract: Our previous studies have shown that z-guggulsterone, a constituent of Indian Ayurvedic medicinal plant Commiphora mukul, inhibits the growth of human prostate cancer cells by causing apoptosis. We now report a novel response to z-guggulsterone involving the inhibition of angiogenesis in vitro and in vivo. The z-guggulsterone treatment inhibited capillary-like tube formation (in vitro neovascularization) by human umbilical vein endothelial cells (HUVEC) and migration by HUVEC and DU145 human prostate cancer cells in a concentration- and time-dependent manner. The z- and E-isomers of guggulsterone seemed equipotent as inhibitors of HUVEC tube formation. The z-guggulsterone-mediated inhibition of angiogenesis in vitro correlated with the suppression of secretion of proangiogenic growth factors [e.g., vascular endothelial growth factor (VEGF) and granulocyte colony-stimulating factor], down-regulation of VEGF receptor 2 (VEGF-R2) protein level, and inactivation of Akt. The z-guggulsterone-mediated suppression of DU145 cell migration was increased by knockdown of VEGF-R2 protein level. Ectopic expression of constitutively active Akt in DU145 cells conferred protection against z-guggulsterone-mediated inhibition of cell migration. Oral gavage of 1 mg z-guggulsterone/d (five times/wk) to male nude mice inhibited in vivo angiogenesis in DU145-Matrigel plug assay as evidenced by a statistically significant decrease in tumor burden, microvessel area (staining for angiogenic markers factor VIII and CD31), and VEGF-R2 protein expression. In conclusion, the present study reveals that z-guggulsterone inhibits angiogenesis by suppressing the VEGF-VEGF-R2-Akt signaling axis. Together, our results provide compelling rationale for further preclinical and clinical investigation of z-guggulsterone for its efficacy against prostate cancer.
authors.affiliation: Department of Pharmacology and University of Pittsburgh Cancer Institute, School of Medicine, Pittsburgh, PA 15213, USA.
authors.forename: Dong
authors.initials: D
authors.lastname: Xiao
authors.forename: Shivendra V
authors.initials: SV
authors.lastname: Singh
mesh_terms: D020533:Angiogenesis Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D000818:Animals; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D003094:Collagen / Q000378:metabolism; D029744:Commiphora / Q000737:chemistry*; D004338:Drug Combinations; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D007797:Laminin / Q000378:metabolism; D008297:Male; D008515:Medicine, Ayurvedic; D051379:Mice; D015394:Molecular Structure; D011282:Pregnenediones / Q000737:chemistry / Q000494:pharmacology*; D011471:Prostatic Neoplasms / Q000378:metabolism / Q000473:pathology; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011509:Proteoglycans / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000037:antagonists & inhibitors / Q000378:metabolism; D014470:Umbilical Cord / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism; D023041:Xenograft Model Antitumor Assays
chemical_list: D020533:Angiogenesis Inhibitors; D004338:Drug Combinations; D036341:Intercellular Signaling Peptides and Proteins; D007797:Laminin; D011282:Pregnenediones; D047428:Protein Kinase Inhibitors; D011509:Proteoglycans; C059485:matrigel; D003094:Collagen; C023617:pregna-4,17-diene-3,16-dione; D040301:Vascular Endothelial Growth Factor Receptor-2; D051057:Proto-Oncogene Proteins c-akt