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Xiao Zhong Peng - One of the best experts on this subject based on the ideXlab platform.

Fei Wang - One of the best experts on this subject based on the ideXlab platform.

  • Role of Non-Receptor Tyrosine Kinase Tec in the production of pro-inflammatory cytokines from macrophages induced by endotoxin/lipopolysaccharide
    Zhonghua shao shang za zhi = Zhonghua shaoshang zazhi = Chinese journal of burns, 2015
    Co-Authors: Chao Wang, Fei Wang, Bo Zhou, Le Qiu, Jian Wang, Sheng Liu, Xu-lin Chen
    Abstract:

    Objective To investigate the role of non–receptor Tyrosine Kinase Tec in the production of TNF–α and IL–1β from macrophages induced by LPS and its related mechanism. Methods RAW264.7 mononuclear–macrophages cultured in 6–well plates were divided into 4 groups according to the random number table, with 24 wells in each group. Cells in blank group were routinely cultured (cultured with DMEM medium containing 10% FBS) for 2 hours. Cells in LFM–A13 group were pretreated with 75 μmol/L Tec specific inhibitor LFM–A13 for 1 hour and then routinely cultured for 1 hour. Cells in LPS group were routinely cultured for 1 hour and then treated with 0.1 μg/mL LPS for 1 hour. Cells in LPS+ LFM–A13 group were pretreated with 75 μmol/L LFM–A13 for 1 hour and then treated with 0.1 μg/mL LPS for 1 hour. The content of TNF–α and IL–1β in culture supernatant of cells was determined with ELISA. The mRNA expressions of TNF–α and IL–1β in cells were assayed with real–time fluorescent quantitative RT–PCR. The activity of intracellular Tec, p38 MAPK, and transforming growth factor activated Kinase 1 (TAK1) was determined with Western blotting. Data were processed with one–way analysis of variance and LSD test. Results The content of TNF–α and IL–1β in culture supernatant of cells in LFM–A13 group was close to that in blank group (with P values above 0.05). The mRNA expressions of TNF–α and IL–1β in the cells of LFM–A13 group were close to those of blank group (with P values above 0.05). The content of TNF–α and IL–1β in culture supernatant of cells in LPS group was respectively (1 213±154) and (636±90) pg/mL, which was higher than that in blank group [(330±44) and (211±31) pg/mL, with P values below 0.01]. The mRNA expressions of TNF–α and IL–1β in the cells of LPS group were respectively 1.57±0.22 and 1.44±0.24, which were significantly higher than those of blank group (1.00±0.18 and 1.00±0.19, with P values below 0.01). The content of TNF–α and IL–1β in culture supernatant of cells in LPS+ LFM–A13 group was respectively (787±109) and (453±64) pg/mL, which was significantly lower than that in LPS group (with P values below 0.05). The mRNA expressions of TNF–α and IL–1β in the cells of LPS+ LFM–A13 group were respectively 1.21±0.15 and 1.21±0.22, and they were significantly lower than those of LPS group (with P values below 0.05). The activity of intracellular Tec, TAK1, and p38 MAPK of cells in LPS+ LFM–A13 group was close to that in blank group (with P values above 0.05). The activity of intracellular Tec, TAK1, and p38 MAPK of cells in LPS group was respectively 2.69±0.41, 3.99±0.65, and 2.07±0.31, which was significantly higher than that in blank group (1.00±0.17, 1.00±0.16, and 1.00±0.18, with P values below 0.01) and LPS+ LFM–A13 group (1.02±0.17, 1.18±0.20, and 1.58±0.28, P

  • The Non-Receptor Tyrosine Kinase Lyn controls neutrophil adhesion by recruiting the CrkL-C3G complex and activating Rap1 at the leading edge.
    Journal of cell science, 2011
    Co-Authors: Ashish Kapoor, Sara Cook, Shubai Liu, Yang Xiang, Christopher V Rao, Paul J A Kenis, Fei Wang
    Abstract:

    Establishing new adhesions at the extended leading edges of motile cells is essential for stable polarity and persistent motility. Despite recent identification of signaling pathways that mediate polarity and chemotaxis in neutrophils, little is known about molecular mechanisms governing cell-extracellular-matrix (ECM) adhesion in these highly polarized and rapidly migrating cells. Here, we describe a signaling pathway in neutrophils that is essential for localized integrin activation, leading edge attachment and persistent migration during chemotaxis. This pathway depends upon G(i)-protein-mediated activation and leading edge recruitment of Lyn, a Non-Receptor Tyrosine Kinase belonging to the Src Kinase family. We identified the small GTPase Rap1 as a major downstream effector of Lyn to regulate neutrophil adhesion during chemotaxis. Depletion of Lyn in neutrophil-like HL-60 cells prevented chemoattractant-induced Rap1 activation at the leading edge of the cell, whereas ectopic expression of Rap1 largely rescued the defects induced by Lyn depletion. Furthermore, Lyn controls spatial activation of Rap1 by recruiting the CrkL-C3G protein complex to the leading edge. Together, these results provide novel mechanistic insights into the poorly understood signaling network that controls leading edge adhesion during chemotaxis of neutrophils, and possibly other amoeboid cells.

  • The Non-Receptor Tyrosine Kinase Lyn controls neutrophil adhesion by recruiting the CrkL−C3G complex and activating Rap1 at the leading edge
    Journal of Cell Science, 2011
    Co-Authors: Ashish Kapoor, Shubai Liu, Yang Xiang, Christopher V Rao, Paul J A Kenis, Sara L. Cook, Fei Wang
    Abstract:

    Establishing new adhesions at the extended leading edges of motile cells is essential for stable polarity and persistent motility. Despite recent identification of signaling pathways that mediate polarity and chemotaxis in neutrophils, little is known about molecular mechanisms governing cell–extracellular-matrix (ECM) adhesion in these highly polarized and rapidly migrating cells. Here, we describe a signaling pathway in neutrophils that is essential for localized integrin activation, leading edge attachment and persistent migration during chemotaxis. This pathway depends upon Gi-protein-mediated activation and leading edge recruitment of Lyn, a Non-Receptor Tyrosine Kinase belonging to the Src Kinase family. We identified the small GTPase Rap1 as a major downstream effector of Lyn to regulate neutrophil adhesion during chemotaxis. Depletion of Lyn in neutrophil-like HL-60 cells prevented chemoattractant-induced Rap1 activation at the leading edge of the cell, whereas ectopic expression of Rap1 largely rescued the defects induced by Lyn depletion. Furthermore, Lyn controls spatial activation of Rap1 by recruiting the CrkL–C3G protein complex to the leading edge. Together, these results provide novel mechanistic insights into the poorly understood signaling network that controls leading edge adhesion during chemotaxis of neutrophils, and possibly other amoeboid cells.

Shaopeng Qiu - One of the best experts on this subject based on the ideXlab platform.

Byeong-seon Jeong - One of the best experts on this subject based on the ideXlab platform.

  • Down-regulation of cathepsin S and matrix metalloproteinase-9 via Src, a Non-Receptor Tyrosine Kinase, suppresses triple-negative breast cancer growth and metastasis
    Experimental & Molecular Medicine, 2018
    Co-Authors: Jaya Gautam, Suhrid Banskota, Yong Hyun Jeon, Byeong-seon Jeong
    Abstract:

    Drugs that inhibit two protein-digesting enzymes could offer potent protection against tumor growth and metastasis in an aggressive form of breast cancer. “Triple-negative breast cancer” (TNBC), which lacks three common tumor biomarkers, carries a poor prognosis for patients, with few treatment options. Enzymes that degrade the protein matrix that anchors tumor cells play a prominent role in metastasis. Researchers led by Jung Ae Kim and Byeong-Seon Jeong at Yeungnam University, Gyeongsan, South Korea, have demonstrated that these enzymes offer potential therapeutic exploitation. The researchers identified a compound that simultaneously suppresses the activity of two different matrix-digesting enzymes. This parallel inhibition markedly reduced tumor growth and metastatic invasion in mouse models of TNBC, with minimal toxicity to non-cancerous cells. This approach could thus offer new hope for treating a challenging class of tumors. Triple-negative breast cancer (TNBC) is a highly metastatic breast cancer with poor prognosis. In the present study, we demonstrated that Src, a Non-Receptor Tyrosine Kinase, might provide an effective therapeutic strategy to overcome TNBC invasion and metastasis, which are mediated via the synergistic action of the lysosomal enzyme cathepsin S (CTSS) and gelatinase MMP-9. Knock-down of MMP-9 and CTSS using siRNAs resulted in a synergistic suppression of MDA-MB-231 cell invasion, which was similarly observed with pharmacological inhibitors. During the screening of new drug candidates that suppress both CTSS and MMP-9, BJ-2302, a novel 7-azaindolin-2-one derivative, was discovered. Src, an upstream activator of both pathways (PI3K/Akt and Ras/Raf/ERK) responsible for the expression of CTSS and MMP-9, was identified as a high-affinity target of BJ-2302 (IC_90: 3.23 µM) through a Src Kinase assay and a drug affinity responsive target stability (DARTS) assay. BJ-2302 effectively suppressed MDA-MB-231 cell invasion (Matrigel invasion assay) and metastasis (chorioallantoic membrane assay xenografted with MDA-MB-231-luc2-tdTomato cancer cells). Unlike Z-FL-COCHO (potent CTSS inhibitor), BJ-2302 did not induce any cytotoxicity in MCF-10A normal breast epithelial cells. Additionally, BJ-2302 (1 mg/kg) strongly suppressed TNBC cell proliferation in vitro and tumor growth in a xenograft mouse tumor model. The anti-metastatic and anti-tumor effects of BJ-2302 were superior to those of Z-FL-COCHO (1 mg/kg) or batimastat (30 mg/kg), a pan-MMP inhibitor. In summary, inhibition of Src Kinase suppressed TNBC tumor growth and metastasis, and Src inhibitors such as BJ-2302 may constitute a novel therapeutic tool to treat breast cancer that expresses high levels of CTSS and MMP-9.

John K. Heath - One of the best experts on this subject based on the ideXlab platform.

  • the non receptor Tyrosine Kinase ack1 regulates the fate of activated egfr by inducing trafficking to the p62 nbr1 pre autophagosome
    Journal of Cell Science, 2014
    Co-Authors: Sylwia Jones, Joshua Z. Rappoport, Debbie L Cunningham, John K. Heath
    Abstract:

    Growth factor signalling regulates multiple cellular functions and its misregulation has been linked to the development and progression of cancer. Ack1 (activated Cdc42-associated Kinase 1, also known as TNK2) is a Non-Receptor Tyrosine Kinase that has been implicated in trafficking and degradation of epidermal growth factor receptor (EGFR), yet its precise functions remain elusive. In this report, we investigate the role of Ack1 in EGFR trafficking and show that Ack1 partially colocalises to Atg16L-positive structures upon stimulation with EGF. These structures are proposed to be the isolation membranes that arise during formation of autophagosomes. In addition, we find that Ack1 colocalises and interacts with sequestosome 1 (p62/SQSTM1), a receptor for selective autophagy, through a ubiquitin-associated domain, and this interaction decreases upon treatment with EGF, thus suggesting that Ack1 moves away from p62/SQSTM1 compartments. Furthermore, Ack1 interacts and colocalises with NBR1, another autophagic receptor, and this colocalisation is enhanced in the presence of ectopically expressed p62/SQSTM1. Finally, knockdown of Ack1 results in accelerated localisation of EGFR to lysosomes upon treatment with EGF. Structure-function analyses of a panel of Ack1 deletion mutants revealed key mechanistic aspects of these relationships. The Mig6-homology domain and clathrin-binding domain both contribute to colocalisation with EGFR, whereas the UBA domain is essential for colocalisation with p62/SQSTM1, but not NBR1. Taken together, our studies demonstrate a novel role for Ack1 in diverting activated EGFR into a non-canonical degradative pathway, marked by association with p62/SQSTM1, NBR1 and Atg16L.

  • The Non-Receptor Tyrosine Kinase Ack1 regulates the fate of activated EGFR by inducing trafficking to the p62/NBR1 pre-autophagosome.
    Journal of cell science, 2014
    Co-Authors: Sylwia Jones, Joshua Z. Rappoport, Debbie L Cunningham, John K. Heath
    Abstract:

    Growth factor signalling regulates multiple cellular functions and its misregulation has been linked to the development and progression of cancer. Ack1 (activated Cdc42-associated Kinase 1, also known as TNK2) is a Non-Receptor Tyrosine Kinase that has been implicated in trafficking and degradation of epidermal growth factor receptor (EGFR), yet its precise functions remain elusive. In this report, we investigate the role of Ack1 in EGFR trafficking and show that Ack1 partially colocalises to Atg16L-positive structures upon stimulation with EGF. These structures are proposed to be the isolation membranes that arise during formation of autophagosomes. In addition, we find that Ack1 colocalises and interacts with sequestosome 1 (p62/SQSTM1), a receptor for selective autophagy, through a ubiquitin-associated domain, and this interaction decreases upon treatment with EGF, thus suggesting that Ack1 moves away from p62/SQSTM1 compartments. Furthermore, Ack1 interacts and colocalises with NBR1, another autophagic receptor, and this colocalisation is enhanced in the presence of ectopically expressed p62/SQSTM1. Finally, knockdown of Ack1 results in accelerated localisation of EGFR to lysosomes upon treatment with EGF. Structure-function analyses of a panel of Ack1 deletion mutants revealed key mechanistic aspects of these relationships. The Mig6-homology domain and clathrin-binding domain both contribute to colocalisation with EGFR, whereas the UBA domain is essential for colocalisation with p62/SQSTM1, but not NBR1. Taken together, our studies demonstrate a novel role for Ack1 in diverting activated EGFR into a non-canonical degradative pathway, marked by association with p62/SQSTM1, NBR1 and Atg16L.