ABSTRACT
OBJECTIVE: To investigate the effect of sunitinib on the migration of ovarian cells and its mechanism of the negative regulation TGF-ß mediated of epithelial-mesenchymal transition(EMT) by sunitinib to inhibit ovarian cancer metastasis. METHODS: The migration of human ovarian cancer cells SKOV3 was evaluated by wound-healing and transwell assays. The effects of sunitinib on TGF-ß-induced E-cadherin expression was assessed by Western-blotting, real time RT-PCR and immunofluorescence assay. The protein levels of Snail and the transcriptional activity of Smad in sunitinib-treated cells were examined by Western-blotting and SBE-luciferase assay. RESULTS: Sunitinib suppressed the migration of SKOV3 cells in a concentration-dependent manner. TGF-ß stimulation reduced E-cadherin protein level, which was attenuated by sunitinib. Sunitinib inhibited the up-regulation of Snail protein level induced by TGF-ß treatment. The SBE reporter was constructed by linking the Smad-binding elements promoter upstream of luciferase reporter gene. A remarkable increment of transcriptional activity of Smads complexes was observed in SKOV3 cells exposed to TGF-ß, which was significantly prohibited by sunitinib. CONCLUSION: Sunitinib can inhibit the migration of SKOV3 cells and attenuate the down-regulation of E-cadherin protein level induced by TGF-ß. Sunitinib can abolish TGF-ß-induced up-regulation of Snail protein and decrease the transcriptional activity of Smad complexes. The results indicate that sunitinib suppresses migration of ovarian cancer cells through negative modulation of TGF-ß-mediated epithelial-mesenchymal transition.
Subject(s)
Cell Movement/drug effects , Epithelial-Mesenchymal Transition , Indoles/pharmacology , Ovarian Neoplasms/pathology , Pyrroles/pharmacology , Transforming Growth Factor beta/pharmacology , Antigens, CD , Cadherins/metabolism , Cell Line, Tumor/drug effects , Down-Regulation , Female , Humans , Smad Proteins/metabolism , Snail Family Transcription Factors , Sunitinib , Transcription Factors/metabolism , Up-RegulationABSTRACT
Given that Yes-associated protein (YAP) signaling acts as a critical survival input for hypoxic cancer cells in hepatocellular carcinoma (HCC), disruption of YAP function and the maintenance of hypoxia is an attractive way to treat HCC. Utilizing a cell-based YAP-TEAD luciferase reporter assay and functional analyses, we identified CT-707, a China-FDA approved multi-kinase inhibitor under clinical trial with remarkable inhibitory activity against YAP function. CT-707 exhibited prominent cytotoxicity under hypoxia on HCC cells, which was attributable to the inhibition of YAP signaling. CT-707 arrested tumor growth in HepG2, Bel-7402, and HCC patient-derived xenografts. Mechanistically, the inhibitory activity of CT-707 on YAP signaling was due to the interruption of hypoxia-activated IGF1R. Overall, these findings not only identify CT-707 as a promising hypoxia-targeting agent against HCC, but they also unveil IGF1R as a new modulator specifically regulating hypoxia-activated YAP signaling.Significance: CT-707 may represent a novel clinical approach for patients with HCC suffering poor drug response due to intratumor hypoxia. Cancer Res; 78(14); 3995-4006. ©2018 AACR.
Subject(s)
Hypoxia/drug therapy , Liver Neoplasms/drug therapy , Liver Neoplasms/metabolism , Nuclear Proteins/metabolism , Protein Kinase Inhibitors/pharmacology , Receptor, IGF Type 1/metabolism , Transcription Factors/metabolism , Animals , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/metabolism , Cell Cycle Proteins , Cell Line, Tumor , China , Cytotoxins/pharmacology , Hep G2 Cells , Humans , Hypoxia/metabolism , Mice , Mice, Nude , Signal Transduction/drug effectsABSTRACT
Hepatocellular carcinoma is among the leading causes of cancer-related deaths worldwide, and the development of new treatment regimens is urgently needed to improve therapeutic approach. In our study, we found that the combination of a Met inhibitor, cabozantinib, and a novel FAK inhibitor, CT-707, exerted synergistic antitumor effects against hepatocellular carcinoma in vitro and in vivo Interestingly, further studies showed that therapeutic concentrations of cabozantinib increased the phosphorylation of FAK, which might attenuate the antitumor activity of cabozantinib. The simultaneous exposure to CT-707 effectively inhibited the activation of FAK that was induced by cabozantinib, which contributes to the synergistic effect of the combination. Furthermore, cabozantinib increased the mRNA and protein levels of integrin α5, which is a canonical upstream of FAK, and the introduction of cilengitide to block integrin function could abrogate FAK activation by cabozantinib, indicating that cabozantinib upregulated the phosphorylation of FAK in an integrin-dependent manner. Similar synergy was also observed on PHA-665752, another selective MET inhibitor, indicating that this observation might be a common characteristic of MET-targeting strategies. Our findings not only favor the development of the novel FAK inhibitor CT-707 as a therapeutic agent against hepatocellular carcinoma but also provide a new strategy of combining MET and FAK inhibitors to potentiate the anticancer activities of these two types of agents for treating hepatocellular carcinoma patients. Mol Cancer Ther; 15(12); 2916-25. ©2016 AACR.
Subject(s)
Anilides/pharmacology , Carcinoma, Hepatocellular/metabolism , Focal Adhesion Kinase 1/antagonists & inhibitors , Liver Neoplasms/metabolism , Protein Kinase Inhibitors/pharmacology , Pyridines/pharmacology , Anilides/chemistry , Animals , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Survival/drug effects , Disease Models, Animal , Drug Synergism , Enzyme Activation/drug effects , Humans , Liver Neoplasms/drug therapy , Liver Neoplasms/pathology , Phosphorylation , Protein Kinase Inhibitors/chemistry , Proto-Oncogene Proteins c-akt/metabolism , Proto-Oncogene Proteins c-met/antagonists & inhibitors , Proto-Oncogene Proteins c-met/metabolism , Pyridines/chemistry , Signal Transduction/drug effects , Tumor Burden/drug effects , Xenograft Model Antitumor AssaysABSTRACT
Sorafenib is a multikinase inhibitor used as a first-line treatment for advanced hepatocellular carcinoma (HCC), but it has shown modest to low response rates. The characteristic tumour hypoxia of advanced HCC maybe a major factor underlying hypoxia-mediated treatment failure. Thus, it is urgent to elucidate the mechanisms of hypoxia-mediated sorafenib resistance in HCC. In this study, we found that hypoxia induced the nuclear translocation of Yes associate-Protein (YAP) and the subsequent transactivation of target genes that promote cell survival and escape apoptosis, thereby leading to sorafenib resistance. Statins, the inhibitors of hydroxymethylglutaryl-CoA reductase, could ameliorate hypoxia-induced nuclear translocation of YAP and suppress mRNA levels of YAP target genes both in vivo and in vitro. Combined treatment of statins with sorafenib greatly rescued the loss of anti-proliferative effects of sorafenib under hypoxia and improved the inhibitory effects on HepG2 xenograft tumour growth, accompanied by enhanced apoptosis as evidenced by the increased sub-G1 population and PARP cleavage. The expression levels of YAP and its target genes were highly correlated with poor prognosis and predicted a high risk of HCC patients. These findings collectively suggest that statins utilization maybe a promising new strategy to counteract hypoxia-mediated resistance to sorafenib in HCC patients.