RESUMO
Despite many evidences supporting the concept of "oncogene addiction" and many hypotheses rationalizing it, there is still a lack of detailed understanding to the precise molecular mechanism underlying oncogene addiction. In this account, we developed a mathematic model of epidermal growth factor receptor (EGFR) associated signaling network, which involves EGFR-driving proliferation/pro-survival signaling pathways Ras/extracellular-signal-regulated kinase (ERK) and phosphoinositol-3 kinase (PI3K)/AKT, and pro-apoptotic signaling pathway apoptosis signal-regulating kinase 1 (ASK1)/p38. In the setting of sustained EGFR activation, the simulation results show a persistent high level of proliferation/pro-survival effectors phospho-ERK and phospho-AKT, and a basal level of pro-apoptotic effector phospho-p38. The potential of p38 activation (apoptotic potential) due to the elevated level of reactive oxygen species (ROS) is largely suppressed by the negative crosstalk between PI3K/AKT and ASK1/p38 pathways. Upon acute EGFR inactivation, the survival signals decay rapidly, followed by a fast increase of the apoptotic signal due to the release of apoptotic potential. Overall, our systems biology modeling together with experimental validations reveals that inhibition of survival signals and concomitant release of apoptotic potential jointly contribute to the tumor cell death following the inhibition of addicted oncogene in EGFR addicted cancers.
Assuntos
Receptores ErbB/metabolismo , Inativação Gênica , Modelos Biológicos , Neoplasias/enzimologia , Neoplasias/patologia , Oncogenes/genética , Biologia de Sistemas , Ácido Ascórbico/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Simulação por Computador , Ativação Enzimática/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Gefitinibe , Inativação Gênica/efeitos dos fármacos , Humanos , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinazolinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Reprodutibilidade dos Testes , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
Antagonizing angiogenesis-related receptor tyrosine kinase is a promising therapeutic strategy in oncology. In present study, we designed and synthesized a novel vascular endothelial growth factor receptor (VEGFR) inhibitor N-methyl-4-(4-(3-(trifluoromethyl) benzamido) phenoxy) picolinamide SKLB610 that potently suppresses human tumor angiogenesis. SKLB610 inhibited angiogenesis-related tyrosine kinase VEGFR2, fibroblast growth factor receptor 2 (FGFR2) and platelet-derived growth factor receptor (PDGFR) at rate of 97%, 65% and 55%, respectively, at concentration of 10µM in biochemical kinase assays. In vitro, SKLB610 showed more selective inhibition of VEGF-stimulated human umbilical vein endothelial cells (HUVECs) proliferation, and this proliferation inhibitory effect was associated with decreased phosphorylation of VEGFR2 and p42/44 mitogen-activated protein kinase (p42/44 MAPK). Antiangiogenic evaluation showed that SKLB610 inhibited the HUVECs capillary-tube formation on Matrigel in vitro and the sub-intestinal vein formation of zebrafish in vivo. Moreover, SKLB610 inhibited a panel of human cancer cells proliferation in a concentration-dependent manner and human non-small cell lung cancer cell line A549 and human colorectal cancer cell line HCT116 were most sensitive to SKLB610 treatment. In vivo, chronic intraperitoneally administration of SKLB610 at dose of 50mg/kg/d resulted in significant inhibition in the growth of established human A549 and HCT116 tumor xenografts in nude mice without exhibit toxicity. Histological analysis showed significant reductions in intratumoral microvessel density (CD31 staining) of 43-55% relative to controls depending on the specific tumor xenografts. In conclusion, the present study demonstrated that SKLB610 exhibited its antitumor activity as a multi-targeted inhibitor with more potent inhibition of VEGFR2 activity. Its potential to be a candidate of anticancer agent is worth being further investigated.
Assuntos
Inibidores da Angiogênese/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Neovascularização Patológica/tratamento farmacológico , Ácidos Picolínicos/farmacologia , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptores do Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Amidas/síntese química , Amidas/farmacologia , Inibidores da Angiogênese/síntese química , Animais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Colágeno/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Combinação de Medicamentos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Feminino , Humanos , Laminina/metabolismo , Camundongos , Camundongos Nus , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Fosforilação/efeitos dos fármacos , Ácidos Picolínicos/síntese química , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Proteoglicanas/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Veias Umbilicais/citologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-ZebraRESUMO
Understanding the regulation of mitotic entry is one of the most important goals of modern cell biology, and computational modeling of mitotic entry has been a subject of several recent studies. However, there are still many regulation mechanisms that remain poorly characterized. Two crucial aspects are how mitotic entry is controlled by its upstream regulators Aurora-A and Plk1, and how mitotic entry is coordinated with other biological events, especially G2/M checkpoint. In this context, we reconstructed a comprehensive computational model that integrates the mitotic entry network and the G2/M checkpoint system. Computational simulation of this model and subsequent experimental verification revealed that Aurora-A and Plk1 are redundant to the activation of cyclin B/Cdk1 during normal mitotic entry, but become especially important for cyclin B/Cdk1 activation during G2/M checkpoint recovery. Further analysis indicated that, in response to DNA damage, Chk1-mediated network rewiring makes cyclin B/Cdk1 more sensitive to the down-regulation of Aurora-A and Plk1. In addition, we demonstrated that concurrently targeting Aurora-A and Plk1 during G2/M checkpoint recovery achieves a synergistic effect, which suggests the combinational use of Aurora-A and Plk1 inhibitors after chemotherapy or radiotherapy. Thus, the results presented here provide novel insights into the regulation mechanism of mitotic entry and have potential value in cancer therapy.
Assuntos
Proteínas de Ciclo Celular/metabolismo , Ciclo Celular/fisiologia , Biologia Computacional , Modelos Biológicos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Algoritmos , Aurora Quinases , Western Blotting , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Inibidores Enzimáticos/farmacologia , Células HeLa , Humanos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Quinase 1 Polo-LikeRESUMO
In this study, 3D-pharmacophore models of Aurora B kinase inhibitors have been developed by using HipHop and HypoGen modules in Catalyst software package. The best pharmacophore model, Hypo1, which has the highest correlation coefficient (0.9911), consists of one hydrogen-bond acceptor, one hydrogen-bond donor, one hydrophobic aliphatic moiety and one ring aromatic feature. Hypo1 was validated by test set and cross-validation methods. And the specificity of Hypo1 to Aurora B inhibitors was examined with the use of selective inhibitors against Aurora B and its paralogue Aurora A. The results clearly indicate that Hypo1 can differentiate selective inhibitors of Aurora B from those of Aurora A, and the ring aromatic feature likely plays some important roles for the specificity of Hypo1. Then Hypo1 was used as a 3D query to screen several databases including Specs, NCI, Maybridge and Chinese Nature Product Database (CNPD) for identifying new inhibitors of Aurora B. The hit compounds were subsequently subjected to filtering by Lipinski's rule of five and docking studies to refine the retrieved hits, and some compounds selected from the top ranked hits have been suggested for further experimental assay studies.
Assuntos
Simulação por Computador , Desenho de Fármacos , Modelos Moleculares , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Aurora Quinase B , Aurora Quinases , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Proteínas Serina-Treonina Quinases/química , Reprodutibilidade dos Testes , Software , Relação Estrutura-AtividadeRESUMO
Pharmacophore models of Polo-like kinase-1 (PLK1) inhibitors have been established by using the HipHop and HypoGen algorithms implemented in the Catalyst software package. The best quantitative pharmacophore model, Hypo1, which has the highest correlation coefficient (0.9895), consists of one hydrogen bond acceptor, one hydrogen bond donor, one hydrophobic feature, and one hydrophobic aliphatic feature. Hypo1 was further validated by test set and cross validation method. Then Hypo1 was used as a 3D query to screen several databases including Specs, NCI, Maybridge, and Chinese Nature Product Database (CNPD). The hit compounds were subsequently subjected to filtering by Lipinski's rule of five and docking study to refine the retrieved hits and as a result to reduce the rate of false positive. Finally, a total of 20 compounds were selected and have been shifted to in vitro and in vivo studies. As far as we know, this is the first report on the pharmacophore modeling even the first publicly reported virtual screening study of PLK1 inhibitors.
Assuntos
Proteínas de Ciclo Celular/antagonistas & inibidores , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/farmacologia , Modelos Moleculares , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Algoritmos , Compostos Heterocíclicos/química , Concentração Inibidora 50 , Estrutura Molecular , Relação Estrutura-Atividade , Quinase 1 Polo-LikeRESUMO
Aurora-A has been identified as one of the most attractive targets for cancer therapy and a considerable number of Aurora-A inhibitors have been reported recently. In order to clarify the essential structure-activity relationship for the known Aurora-A inhibitors as well as identify new lead compounds against Aurora-A, 3D pharmacophore models were developed based on the known inhibitors. The best hypothesis, Hypo1, was used to screen molecular structural databases, including Specs and China Natural Products Database for potential lead compounds. The hit compounds were subsequently subjected to filtering by Lipinski's rules and docking study to refine the retrieved hits and as a result to reduce the rate of false positive. Finally, 39 compounds were purchased for further in vitro assay against several human tumour cell lines including A549, MCF-7, HepG2 and PC-3, in which Aurora-A is overexpressed. Two compounds show very low micromolar inhibition potency against some of these tumour cells. And they have been selected for further investigation.