AIM:To investigate the effects of macrophage migration inhibitory factor (MIF) on proliferation of human gastric cancer MGC-803 cells and expression of cyclin D1 and p27Kip1 in them,and further determine whether the e...AIM:To investigate the effects of macrophage migration inhibitory factor (MIF) on proliferation of human gastric cancer MGC-803 cells and expression of cyclin D1 and p27Kip1 in them,and further determine whether the effects are related to the PI3K/Akt signal transduction pathway. METHODS:Gastric cancer MGC-803 cells were cultured and then treated with 50 μg/L recombinant human MIF (rhMIF) with and without a PI3K inhibitor,LY294002 (25 μmol/L). MTT assay was used to detect the prolifer-ation of MGC-803 cells. Cell cycle was detected by flow cytometry. Expression of cyclin D1 and p27Kip1 mRNA was by reverse transcription-polymerase chain reaction. Protein expression of phosphorylated Akt (p-Akt),Akt,cyclin D1 and p27Kip1 was examined by immunocyto-chemistry and Western blotting. RESULTS:rhMIF signifi cantly stimulated the prolifera-tion of MGC-803 cells and cell cycle progression from G1 phase to S phase in a concentration-and time-de-pendent manner. After the MGC-803 cells were treated with rhMIF for 24 h,the expression of cyclin D1 was signifi cantly up-regulated compared with the cells not treated with rhMIF at both mRNA and protein levels(0.97 ± 0.02 vs 0.74 ± 0.01,P = 0.002; 0.98 ± 0.05 vs 0.69 ± 0.04,P = 0.003). The p27Kip1 was down-regulated but only statistically significant at the protein level. rhMIF significantly increased the expression of p-Akt,which reached the peak at 30 min,but did not affect the expression of Akt. However,LY294002 inhibited all the effects of rhMIF.CONCLUSION:Macrophage MIF increases the proliferation of gastric cancer cells,induces the expression of cyclin D1 at the transcriptional level and inhibits the expression of p27Kip1 at the post-transcriptional level via the PI3K/Akt pathway.展开更多
The aim of this study is to elucidate the molecular and cellular mechanisms underlying the immunosuppressive effect of Sanchi extract （SE） via investigating the effects of SE on the activation and proliferation of m...The aim of this study is to elucidate the molecular and cellular mechanisms underlying the immunosuppressive effect of Sanchi extract （SE） via investigating the effects of SE on the activation and proliferation of murine lymphocytes and NO secretion by peritoneal macrophages in vitro. ConA was used to activate lymphecytes, and expression of CD69 on T cells and CFSE labeled cell division were detected by flow cytometry. Murine peritoneal macrophages were stimulated with LPS or lymphocytes culture supernate （LCS） and the concentration of NO was determined by Griess reagent assay. After 6 h of culture, SE ranging from 50 to 100μg/ml downregulated CD69 expression on ConA-activated T cells, while SE ranging from 12.5 to 100μg/ml inhibited the proliferative response of lymphocytes to ConA. Additionally, SE （12.5-100μg/ml） inhibited secretion of NO by peritoneal macrophages stimulated by LPS or LCS. This study reveals that SE inhibits the activation and proliferation of routine lymphocytes and NO secretion by peritoneal macrophages.展开更多
基金Supported by Grant from Hunan Provincial Science and Technology Department (2008 FJ 3088), China
文摘AIM:To investigate the effects of macrophage migration inhibitory factor (MIF) on proliferation of human gastric cancer MGC-803 cells and expression of cyclin D1 and p27Kip1 in them,and further determine whether the effects are related to the PI3K/Akt signal transduction pathway. METHODS:Gastric cancer MGC-803 cells were cultured and then treated with 50 μg/L recombinant human MIF (rhMIF) with and without a PI3K inhibitor,LY294002 (25 μmol/L). MTT assay was used to detect the prolifer-ation of MGC-803 cells. Cell cycle was detected by flow cytometry. Expression of cyclin D1 and p27Kip1 mRNA was by reverse transcription-polymerase chain reaction. Protein expression of phosphorylated Akt (p-Akt),Akt,cyclin D1 and p27Kip1 was examined by immunocyto-chemistry and Western blotting. RESULTS:rhMIF signifi cantly stimulated the prolifera-tion of MGC-803 cells and cell cycle progression from G1 phase to S phase in a concentration-and time-de-pendent manner. After the MGC-803 cells were treated with rhMIF for 24 h,the expression of cyclin D1 was signifi cantly up-regulated compared with the cells not treated with rhMIF at both mRNA and protein levels(0.97 ± 0.02 vs 0.74 ± 0.01,P = 0.002; 0.98 ± 0.05 vs 0.69 ± 0.04,P = 0.003). The p27Kip1 was down-regulated but only statistically significant at the protein level. rhMIF significantly increased the expression of p-Akt,which reached the peak at 30 min,but did not affect the expression of Akt. However,LY294002 inhibited all the effects of rhMIF.CONCLUSION:Macrophage MIF increases the proliferation of gastric cancer cells,induces the expression of cyclin D1 at the transcriptional level and inhibits the expression of p27Kip1 at the post-transcriptional level via the PI3K/Akt pathway.
基金This work was supported by the National Natural Science Foundation of China(30230350 and 30500466).
文摘The aim of this study is to elucidate the molecular and cellular mechanisms underlying the immunosuppressive effect of Sanchi extract （SE） via investigating the effects of SE on the activation and proliferation of murine lymphocytes and NO secretion by peritoneal macrophages in vitro. ConA was used to activate lymphecytes, and expression of CD69 on T cells and CFSE labeled cell division were detected by flow cytometry. Murine peritoneal macrophages were stimulated with LPS or lymphocytes culture supernate （LCS） and the concentration of NO was determined by Griess reagent assay. After 6 h of culture, SE ranging from 50 to 100μg/ml downregulated CD69 expression on ConA-activated T cells, while SE ranging from 12.5 to 100μg/ml inhibited the proliferative response of lymphocytes to ConA. Additionally, SE （12.5-100μg/ml） inhibited secretion of NO by peritoneal macrophages stimulated by LPS or LCS. This study reveals that SE inhibits the activation and proliferation of routine lymphocytes and NO secretion by peritoneal macrophages.
