As expected, dose dependence was found in the inhibitory effects of doviti nib on the phosphorylation of PDGFR B, VEGFR 2, and FGFR 1, as well as their AZD9291 cost major downstream effector, the phosphorylation of ERK, on these cells, but not the phosphorylation of Akt. While the levels of cleaved PARP and cleaved caspase 3 were also readily detected in dose dependence of dovitinib. The proliferation of endothelial cells was inhibited by dovitinib Only two HCC cell lines, MHCC 97H and SMMC7721, expressed PDGFR B. Therefore, we compared the inhibi tory effect of dovitinib on proliferation in these two lines and in endothelial cell lines. The IC50 for dovitinib to inhibit the proliferation of HCC cell lines was 0. 870. 17 umolL and 1. 260. 15 umolL for MHCC 97H and SMMC7721, respectively.
While dovitinib showed robust inhibitory effect of endothelial cells under VEGF dependent conditions were 0. 04 umolL, which was similar to the concentrations required to inhibit activa tion of VEGFR 2. The IC50 values of MHCC 97H and SMMC7721 cells were much higher than that needed to inhibit the activation of PDGFR B, suggesting that targeting Inhibitors,Modulators,Libraries of PDGFR B by dovitinib did not influence the proliferation of these cells. Dovitinib inhibited the migration of endothelial Inhibitors,Modulators,Libraries cells but not of HCC cells Figure 4 shows that at pharmacologically relevant con centrations, dovitinib inhibited the migration and inva sion of endothelial cells as evaluated by Transwell assay and wound healing assay. The motility of MHCC 97H, SMMC7721 and QGY7703 was very weak in the wound healing Inhibitors,Modulators,Libraries assay, and dovitinib did not show an significantly inhibitory effect on their migration of MHCC 97H.
Dovitinib inhibited tumor angiogenesis in vivo To further elucidate the mechanism of dovitinib mediated inhibition of growth and metastasis in vivo, we collected xenograft tumor samples and examined the ef fect of dovitinib on the tumor vasculature as well as on HCC cell proliferation and apoptosis. Immunohisto chemical analyses Inhibitors,Modulators,Libraries revealed that the markers of endothe lial cell and pericyte expressed homogeneously in tumor sample, and dovitinib sig nificantly decreased microvessel density in MHCC 97H cells by 61. 5% and 78. 8% at doses of 25 mgkg and 50 mgkg, respectively. MVD was decreased by 58. 3% and 74. 8%, respectively, in SMMC7721 cells and by 57. 9% and 82. Inhibitors,Modulators,Libraries 6% in QGY 7703 cells.
In com parison with the robust inhibition of angiogenesis, the effects of dovitinib on inhibiting proliferation and enhancing apoptosis of HCC cells in vivo were modest, although significant, suggesting that direct tar geting HCC cells by dovitinib selleck catalog might not be the primary event inhibiting tumor growth in vivo. Discussion Dovitinib is currently in Phase II studies for the treatment of advanced hepatocellular carcinoma, but the underlying mechanism of dovitinib in targeting HCC is not known.