Epidermal growth factor receptor tyrosine kinases inhibitor (EGFR-TKI) has impressive clinical efficacy in EGFR-mutant non-small cell lung cancer. However,there are still some patients with primary resistance to TKI.And most patients who initially respond to treatment eventually develop resistance to these drugs,which the main molecular mechanisms are T790M and MET amplification.The new targeted therapies and combination drugs to overcome drug resistance is the subject of clinical research.

AIM: To investigate the effects of transforming growth factor ?1 (TGF-?1) on murine-derived dendritic cells (DC). METHODS: Murine bone marrow cells were cultured with GM-CSF and TGF-?1 to develop TGF ?-DC. Then they were stimulated by lipopolysaccharide (LPS). Their phenotypes were assessed by flow cytometry (FCM). The allogeneic stimulating capacity of DC was measured by mixed lymphocyte reaction (MLR) using BrdU ELISA method. IL-12 p70 protein was detected by ELISA and the expressions of Toll like receptor 4 (TLR4) on DCs were measured by semi-quantitative RT-PCR and FCM. RESULTS: Compared to immature DC (imDC) cultured with GM-CSF alone, the expressions of CD_80, CD_86, I-A~b and CD_40 in TGF ?-DC were lower. The TGF ?-DC was resistant to maturation by LPS. Maturation resistance was evident from a failure to up-regulate CMs, to stimulate larger T cell proliferation and to increase secretion of IL-12 p70. Down-regulation of TLR4 expression on TGF ?-DC was also found. CONCLUSION: TGF-?1 inhibits the expression of co-stimulatory molecules on DC. It is resistant to maturation stimulus (LPS) and might be linked with TLR4 down-regulation.

AIM: To explore the influence of CD47 molecules on the maturation and function of cultured dendritic cells (DCs). METHODS: Monocyte cell-derived DCs were propagated in granulocyte-macrophage colony-stimulating factor (GM-CSF) and lipopolysaccharide (LPS) plus interleukin (IL)-4, in the presence or absence of anti CD47 monoclonal antibodies (anti-CD47 mAbs). Flow cytometry was used to detect the cell surface phenotype. The concentration of IL-12P70 in supernatant was measured by ELISA technique. The antigen-presenting functions of DCs were determined in one-way mixed leukocyte reaction by Brdu-ELISA. Electrophoretic mobility shift assays (EMSA) was used to examine NF-?B activity. RESULTS: The anti-CD47 mAbs markedly suppressed the expression of CD80,CD86,CD83,CD1a,HLA-DR on the surface of DCs (P