Differential Responses of MET Activations to MET kinase Inhibitor and Neutralizing Antibody

Background: Aberrant MET tyrosine kinase signaling is known to cause cancer initiation and progression. While MET inhibitors are in clinical trials against several cancer types, the clinical efficacies are controversial and the molecular mechanisms toward sensitivity remain elusive. Methods: With the goal to investigate the molecular basis of MET amplification (MET amp ) and hepatocyte growth factor (HGF) autocrine-driven tumors in response to MET tyrosine kinase inhibitors (TKI) and neutralizing antibodies, we compared cancer cells harboring MET amp (MKN45 and MHCCH97H) or HGF-autocrine (JHH5 and U87) for their sensitivity and downstream biological responses to a MET-TKI (INC280) and an anti-MET monoclonal antibody (MetMab) in vitro, and for tumor inhibition in vivo. Results: We find that cancer cells driven by MET amp are more sensitive to INC280 than are those driven by HGF-autocrine activation. In MET amp cells, INC280 induced a DNA damage response with activation of repair through the p53BP1/ATM signaling pathway. Although MetMab failed to inhibit MET amp cell proliferation and tumor growth, both INC280 and MetMab reduced HGF-autocrine tumor growth. In addition, we also show that HGF stimulation promoted human HUVEC cell tube formation via the Src pathway, which was inhibited by either INC280 or MetMab. These observations suggest that in HGF-autocrine tumors, the endothelial cells are the secondary targets MET inhibitors. Conclusions: Our results demonstrate that MET amp and HGF-autocrine activation favor different molecular mechanisms. While combining MET TKIs and ATM inhibitors may enhance the efficacy for treating tumors harboring MET amp , a combined inhibition of MET and angiogenesis pathways may improve the therapeutic efficacy against HGF-autocrine tumors

Development and application of an informatization upgrade device for old equipment in ceramic sanitary ware industry

A device is proposed, which can be used to upgrade the informatization process of old equipment and information isolated island equipment of ceramic enterprises. It has the characteristics of standard, high efficiency, low cost and low risk. The universal fast interface does not interfere with the control system of the device itself when connected to the device. It can obtain data that the target device system has but is not open or the system does not have. Then, the device use the standard industrial communication protocol to transmit the data to the manufacturing execution system in accordance with the agreed data format. This method lay a good foundation for the informatization upgrade and optimization of the data. Furthermore it can be used to optimize and control production. Finally, in enterprise applications, it shows that the device has certain economic and social benefits

Lead adsorption on loess under high ammonium environment

Lead (Pb) is one of the most toxic, hazardous pollutants available in landfill leachate. Loess-amended soil buffers are found suitable and effective in attenuating migration of Pb and the other trace metals. High concentration of ammonium (NH4+ > 1000 mg/l) is also reported in landfill leachate, and therefore, it is essential to investigate the transport of lead under such condition. In this study, the mechanisms and the capacity of loess to adsorb Pb under high NH4+ concentration were investigated. Adsorption isotherm test data were obtained for 25 °C, 35 °C and 45 °C. The maximum adsorption capacity is estimated to be 2101.97 mg/g at 25 °C and 4292.8 mg/g at 45 °C under 1000 mg/l NH4+. The binding sites of Pb on loess are positively related to each other at low temperatures (25–35 °C). The thermodynamic analysis indicates that adsorption process is endothermic and non-spontaneous and the system randomness increases with reaction time. The kinetic test data, fitted with a pseudo-second-order kinetic model and an intraparticle diffusion model, suggests that removal of Pb is driven by both membrane and intraparticle diffusions. The SEM, XRD and FTIR analyses indicate flocculation, precipitations as well as some ion exchange processes, which perhaps combinedly increases adsorption of both NH4+ and Pb in loess. The two kinds of precipitations are involved for the removal of Pb. The precipitations of PbCO3, Pb(OH)2 and PbCO3·2H2O are formed by the reactions between calcite and lead. The other precipitation of white basic salt (Pb2O(NO3)2) is formed by the reactions among Pb2+, NO3− and aqueous ammonia under alkaline environment of loess slurry

Luminescence-Tunable Polynorbornenes for Simultaneous Multicolor Imaging in Subcellular Organelles

Through modular ROMP (ring-opening metathesis polymerization), biofunctional polynorbornenes are designed and fabricated from panchromatic fluorophores, bioactive peptides, and polyethylene glycol solubilizer for organelle-specific multicolor imaging. Attributed to the free permutation and combination of highly fluorescent red rhodamine B, green dichlorofluorescein and blue 9,10-diphenylanthracene fluorophores as well as signaling peptide sequences of F_<i>x</i>rF_<i>x</i>K and TAT, we successfully realize simultaneous multicolor imaging toward lysosomes and mitochondria in living cells first utilizing polymeric scaffolds. If more biofunctions could be incorporated, modularly designed copolymer would provide a promising opportunity to facilitate multitasking application to monitoring intracellular alterations and elucidating complex biological processes

Overexpression of HGF/MET axis along with p53 inhibition induces de novo glioma formation in mice

BACKGROUND: Aberrant MET receptor tyrosine kinase (RTK) activation leads to invasive tumor growth in different types of cancer. Overexpression of MET and its ligand hepatocyte growth factor (HGF) occurs more frequently in glioblastoma (GBM) than in low-grade gliomas. Although we have shown previously that HGF-autocrine activation predicts sensitivity to MET tyrosine kinase inhibitors (TKIs) in GBM, whether it initiates tumorigenesis remains elusive. METHODS: Using a well-established Sleeping Beauty (SB) transposon strategy, we injected human and cDNA together with a short hairpin siRNA against (SB-hHgf.Met.ShP53) into the lateral ventricle of neonatal mice to induce spontaneous glioma initiation and characterized the tumors with H&E and immunohistochemistry analysis. Glioma sphere cells also were isolated for measuring the sensitivity to specific MET TKIs. RESULTS: Mixed injection of SB-hHgf.Met.ShP53 plasmids induced de novo glioma formation with invasive tumor growth accompanied by HGF and MET overexpression. While glioma stem cells (GSCs) are considered as the tumor-initiating cells in GBM, both SB-hHgf.Met.ShP53 tumor sections and glioma spheres harvested from these tumors expressed GSC markers nestin, GFAP, and Sox 2. Moreover, specific MET TKIs significantly inhibited tumor spheres\u27 proliferation and MET/MAPK/AKT signaling. CONCLUSIONS: Overexpression of the HGF/MET axis along with p53 attenuation may transform neural stem cells into GSCs, resulting in GBM formation in mice. These tumors are primarily driven by the MET RTK pathway activation and are sensitive to MET TKIs. The SB-hHgf.Met.ShP53 spontaneous mouse glioma model provides a useful tool for studying GBM tumor biology and MET-targeting therapeutics

Differential Therapeutic Responses of MET Oncogenic Activations to MET Kinase Inhibitor and Neutralizing Antibody

Purpose: MET inhibitors are in clinical trials against several cancer types, but the mechanisms toward vulnerability remain elusive. Here we characterized the molecular basis of MET amplification (METamp) and HGF-autocrine driven tumors in response to MET tyrosine kinase inhibitors (TKI) and neutralizing antibodies. Experimental Design: METamp (MKN45 and MHCC97H) and HGF-autocrine activation (JHH5 and U87) cells were treated by the MET kinase inhibitor (INC280) and the anti-MET monoclonal antibody (MetMab) to determine the sensitivity and biological responses in vitro. Tumor inhibition was evaluated in vivo using SCID and SCIDhgf mouse models, respectively. HGF-mediated angiogenesis was measured by using the human endothelial cells (HUVEC) tube formation assay. Results: MKN45 and MHCC97H cells are more sensitive than JHH5 and U87 cells to INC280 treatment but are unresponsive to MetMab. In METamp cells, INC280 induced a DNA damage response with activation of repair through the p53BP1/ATM signaling pathway. Although INC280 and MetMab showed a moderate inhibitory effect on JHH5 and U87 cells in vitro, both treatments potently suppressed tumor growth in mouse models. We found that HGF stimulation promotes human HUVEC cell tube formation via the Src pathway. INC280 or MetMab inhibited tube formation; thus in HGF-autocrine tumors, the endothelial cells are the secondary targets of tumor-derived HGF and MET inhibition. Conclusion: METamp and HGF-autocrine activation favor different molecular mechanisms, such as a DNA damage response or angiogenesis. Because individual types of MET oncogenic activation may respond to MET inhibitors differently, combination strategies should be developed based upon the molecular subtypes of the tumors