ABSTRACT
Background and purpose:Hepatocyte growth factor (HGF) induce epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) resistance in non-small cell lung cancer (NSCLC) cells, the mechanism might be related with activation of c-Met. The present study aimed to explore whether c-Met inhibitor SU11274 reverse gefitinib resistance induced by HGF in differentEGFR gene types of NSCLC.Methods:PC9 (EGFR-activating mutant), H292 (EGFR-wild type) and A549 (EGFR-wiled) were chosen. The experiments were divided into 6 groups:C group (control), H group (HGF), G group (geiftinib), S group (SU11274), GH group (geiftinib+HGF), GSH group (geiftinib+SU11274+HGF). The cell survival was measured by MTT assay; the cell apoptosis was measured by lfow cytometry (FCM); the expressions of c-Met, Stat3, Akt and Erk1/2 protein were examined by Western blot.Results:Gefitinib inhibited cell growth of 3 cells lines in a dose-dependent manner, and treating with HGF could relieve inhibition of cell growth caused by geiftinib. The cell survival when treating the HGF-induced cell lines with defferent concentration of geiftinib combined with SU11274 was signiifcantly decreased than that when treating HGF-induced cell lines with geiftinib alone. In 3 cell lines, the apoptosis rate in HGS group was higher than that in HG group (P<0.05). In three cells lines, the p-Met, p-Stat3, p-Akt and p-Erk1/2 expressions in HGS group were lower than that in HG group (P<0.05).Conclusion:SU11274 reversed geiftinib resistance induced by HGF in different EGFR gene types of NSCLC cells, the mechanism might be related with inhibiting the HGF-induced activation of c-Met and its downstream signaling pathway.
ABSTRACT
Objective To investigate the blocking effects of Pyrin domain protein on mouse allergic airway inflammation induced by ovalbumin and its mechanism.Methods Forty male BALB/c mice were randomly divided into 4 groups with 10 mice in each group.Control group:mice were treated with saline;OVA group:mice were sensitized and challenged with OVA; Pyrin domain protein 3 d group:mice were sensitized and challenged as asthmatic group and treated with 100 μg/kg triptolide before challenged; Pyrin domain protein 7 d group:mice were sensitized and challenged as asthmatic group and treated with 100 μg/kg triptolide before challenged.All mice were killed 24 h after final OVA challenge.The left lung was isolated for pathological examination.Lung sections were stained with hematoxylin and eosin(HE),Masson's trichrome.The thickness of bronchial airway,bronchial smooth muscle thickness,and the collagen deposition area were measured by image analysig system.The concentrations of IL-4,IL-5,TNF-α and IFN-γ in BALF were measured by ELISA,the RT-PCR and Western blot was performed to detect the mRNA expression of connective tissue growth factor (CTGF),TGF-β 1 mRNA and NF -kB from the right lung tissues.Results In OVA group,the number of inflammatory cells and the concentrations of IL-4,IL-5,TNF-a in BALF and Bronchial airway thickness,bronchial smooth muscle thickness,the collagen deposition area,CTGF,TGF-β1 mRNA and NF-kB in lung tissue were significantly higher than those in control group(P＜0.05).IFN-γ were lower than those in control group( P＜0.05 ).While in Pyrin domain protein 3 d group and Pyrin domain protein 7 d group,the number of inflammatory cells,the concentrations of IL-4,IL-5,TNF-α in BALF and bronchial airway thickness,bronchial smooth muscle thickness,the collagen deposition area and NF-kB in lung tissue were significantly lower than those in OVA group,IFN-γwere higher than those in OVA group( P ＜0.05).In Pyrin domain protein 7 d group CTGF and TGF-β1 mRNA in lung tissue were significantly lower than those in OVA group.Conclusion Pyrin domain protein might inhibits airway inflammation and development of airway remodeling in asthmatic mouse,the possible mechanism might in part by associated with reducing the expression of NF-kB and further inhibiting CTGF,TGF-β1.