title: Study of the cellular mechanism of Sunitinib mediated inactivation of activated hepatic stellate cells and its implications in angiogenesis.
abstract: The development of hepatocellular carcinomas from malignant hepatocytes is frequently associated with intra- and peritumoral accumulation of connective tissue arising from activated hepatic stellate cells (HSC). Inhibition of receptor tyrosine kinase (RTK) signaling showed promise in the treatment of hepatocellular carcinoma. However, there is a lack of knowledge about the effects of RTK inhibitors on the tumor supportive cells. We performed in vitro experiments to study whether Sunitinib, a platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) RTKs' inhibitor, could block both activated HSC functions and angiogenesis and thus prevent the progression of cirrhotic liver to hepatocellular carcinoma. In immortalized human activated HSC LX-2, treatment with Sunitinib 100 nM blocked collagen synthesis by 47%, as assessed by Sirius Red staining, attenuated HSC contraction by 65%, and reduced cell migration by 28% as evaluated using a Boyden's chamber, without affecting cell viability, measured by Trypan blue staining, and apoptosis, measured by propidium iodide (PI) incorporation assay. Our data revealed that Sunitinib treatment blocked the transdifferentiation of primary human HSC (hHSC) to activated myofibroblast-like cells by 65% without affecting hHSC apoptosis and migration. In in vitro angiogenic assays, Sunitinib 100 nM reduced endothelial cells (EC) ring formation by 46% and tube formation by 68%, and decreased vascular sprouting in aorta ring assay and angiogenesis in vascular bed of chick embryo. In conclusion, the present study demonstrates that the RTK inhibitor Sunitinib blocks the activation of HSC and angiogenesis suggesting its potential as a drug candidate in pathological conditions like liver fibrosis and hepatocellular carcinoma.
authors: Vascular Biology Lab, Life Sciences Division, AU-KBC Research Centre, Anna University, Chennai 600 044, Tamil Nadu, India.
authors: Syamantak
authors: S
authors: Majumder
authors: Anne-Christine
authors: AC
authors: Piguet
authors: Jean-François
authors: JF
authors: Dufour
authors: Suvro
authors: S
authors: Chatterjee
mesh_terms: D020533:Angiogenesis Inhibitors / Q000494:pharmacology*; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects / Q000502:physiology; D017209:Apoptosis / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002642:Chick Embryo; D003094:Collagen / Q000378:metabolism; D055166:Hepatic Stellate Cells / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D007211:Indoles / Q000494:pharmacology*; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D011758:Pyrroles / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D000077210:Sunitinib; D014945:Wound Healing
chemical_list: D020533:Angiogenesis Inhibitors; D007211:Indoles; D011758:Pyrroles; D003094:Collagen; D000077210:Sunitinib