ABSTRACT
To investigate the effects of airway epithelial cells on macrophages chemotaxis and inflammatory cytokine expression under hypoxic conditions. Methods: Human bronchial epithelial cells (HBE) treated with different concentrations (0, 100, 200, 400, 800 μmol/L) of CoCl2 or transfected with HIF-1α siRNA were co-cultured with THP-1-derived M1 macrophages or M2 macrophages. The chemotactic effects on macrophages were analyzed by Transwell assay. The levels of TNF-α, IFN-γ, IL-4, IL-13 and IL-10 in the supernatants of macrophages were detected by ELISA, and HIF-1α or Cav-1 mRNA expression in HBE or macrophages was detected by RT-qPCR. Results: HBE cells promoted macrophages chemotaxis in a time- and concentration-dependent manner. Compared to un-transfected group, the chemotactic ability of HBE transfected with HIF-1α siRNA was significantly weakened (P<0.01). Under the same culture conditions, the chemotaxis of M2 macrophages was greater than that in THP1-derived M1 macrophages. The concentrations of TNF-α, IFN-γ, IL-4, IL-13 and IL-10 in the supernatants of macrophages were increased in a time-and concentration-dependent manner. The concentrations of TNF-α and IFN-γ were increased further after co-culturing for 8 and 12 h; while IL-4, IL-13 and IL-10 concentrations were increased further during 24 h of co-culture. The levels of cytokines in the supernatants of macrophages co-cultured with HBE and transfected with HIF-1α siRNA were significantly lower than those in un-transfected cells (P<0.05 or P<0.01). The reduction of TNF-α or IFN-γ was more obvious. The expression of HIF-1α or Cav-1 mRNA in HBE or macrophages was increased in a concentration-dependent manner after 8 or 12 h co-culture, which was significantly reduced when HBE was transfected with HIF-1α siRNA. Conclusion: Airway epithelial cells can enhance macrophages chemotaxis and pro-inflammatory cytokines expressions under hypoxic condition. HIF-1α and Cav-1 may be the important mediators in these processes.
Subject(s)
Humans , Cell Hypoxia , Chemotaxis , Cytokines , Epithelial Cells , Hypoxia-Inducible Factor 1, alpha Subunit , MacrophagesABSTRACT
AIM: To explore the anticancer function of Shp2 in lung adenocarcinoma A549 cells and the related molecular mechanisms.METHODS: The viability and proliferation of A549 cells treated with Shp2 specific inhibi-tor Phps-1 or cisplatin (DDP) were measured by CCK-8 assay and EdU assay.Annexin V-FITC/PI double staining was ap-plied to detect apoptotic rate of A549 cells with different interventions.The protein levels of caspase-3-17p, Bcl-2, Bax, p-STAT3 /STAT3 and p-ERK/ERK were determined by Western blot.RESULTS: Compared with control group, Phps-1 at the concentration of 20 μmol/L significantly increased the viability of A549 cells after 24 h of treatment ( P <0.05). Meanwhile, the proliferation rate of A549 cells in Phps-1 20 μmol/L group was significant increased compared with control group (P <0.05).The apoptotic rate of A549 cells in DDP treatment group decreased from 13.01% ±2.62% to 3.67%±0.93% after adding Phps-1 (P <0.05).Phps-1 down-regulated the protein levels of caspase-3-17p, Bax and p-ERK, but up-regulated p-STAT3.CONCLUSION: Shp2 is a tumor suppressor in A549 cells, which may be associated with the activation of STAT3 signal pathway.