AIM: To investigate the effects of Gli-1 small interference RNA (siRNA) on Huh7 cells,and the change of Bcl-2 expression in Huh7 cells. METHODS: Human hepatocellular carcinoma cells Huh7 were used. Cell viability was ...AIM: To investigate the effects of Gli-1 small interference RNA (siRNA) on Huh7 cells,and the change of Bcl-2 expression in Huh7 cells. METHODS: Human hepatocellular carcinoma cells Huh7 were used. Cell viability was analyzed by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The expressions of Gli-1 and Bcl-2 family members were detected by RT-PCR and Western blot. Apoptosis was detected by Flow cytometry using propidium iodide,measured by Hoechst 33258 staining using Advanced Fluorescence Microscopy and caspase-3 enzymatic assay. Cell growth was analyzed after treatment with Gli-1 siRNA and 5-? uorouracil (5-Fu). RESULTS: Inhibition of Gli-1 mRNA in Huh7 cells through Gli-1 siRNA reduced cell viability. Gli-1 siRNA treatment also induced apoptosis by three criteria,increase in the sub-G1 cell cycle fraction,nuclear condensation,a morphologic change typical of apoptosis,and activation of caspase-3. Gli-1 siRNA was also able to down-regulate Bcl-2. However,Gli-1 siRNA resulted in no significant changes in Bcl-xl,Bax,Bad,and Bid. Furthermore,Gli-1 siRNA increased the cytotoxic effect of 5-Fu on Huh7 cell. CONCLUSION: Down-regulation of Bcl-2 plays an important role in apoptosis induced by Gli-1 siRNA in HCC cells. Combination Gli-1 siRNA with chemotherapeutic drug could represent a more promising strategy against HCC. The effects of the strategies need further investigation in vivo and may have potential clinical application.展开更多
Interleukin-15 （IL-15） is essential for the survival of memory CD8^＋ and CD4^＋ T cell subsets, and natural killer and natural killer T cells. Here, we describe a hitherto unreported role of IL-15 in regulating hom...Interleukin-15 （IL-15） is essential for the survival of memory CD8^＋ and CD4^＋ T cell subsets, and natural killer and natural killer T cells. Here, we describe a hitherto unreported role of IL-15 in regulating homoeostasis of naive CD4^＋ T cells. Adoptive transfer of splenocytes from non-obese diabetic （NOD） mice results in increased homeostatic expansion of T cells in lymphopenic NOD.scid.II15^-/- mice when compared to NOD.scid recipients. The increased accumulation of CD4^＋ T cells is also observed in NOD.II15^-/- mice, indicating that IL-15-dependent regulation also occurs in the absence of lymphopenia. NOD.scid mice lacking the I L- 15Ra chain, but not those lacking the common gamma chain, also show increased accumulation of CD4^＋ T cells. These findings indicate that the IL-15-mediated regulation occurs directly on CD4^＋ T cells and requires trans-presentation of IL-15. CD4^＋ T cells expanding in the absence of IL-15 signaling do not acquire the characteristics of classical regulatory T cells. Rather, CD4^＋ T cells expanding in the absence of IL-15 show impaired antigen-induced activation and IFN-7 production. Based on these findings, we propose that the IL-15-dependent regulation of the naive CD4^＋ T-cell compartment may represent an additional layer of control to thwart potentially autoreactive cells that escape central tolerance, while permitting the expansion of memory T cells.展开更多
基金The National Science Foundation of China, No. 30672053
文摘AIM: To investigate the effects of Gli-1 small interference RNA (siRNA) on Huh7 cells,and the change of Bcl-2 expression in Huh7 cells. METHODS: Human hepatocellular carcinoma cells Huh7 were used. Cell viability was analyzed by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The expressions of Gli-1 and Bcl-2 family members were detected by RT-PCR and Western blot. Apoptosis was detected by Flow cytometry using propidium iodide,measured by Hoechst 33258 staining using Advanced Fluorescence Microscopy and caspase-3 enzymatic assay. Cell growth was analyzed after treatment with Gli-1 siRNA and 5-? uorouracil (5-Fu). RESULTS: Inhibition of Gli-1 mRNA in Huh7 cells through Gli-1 siRNA reduced cell viability. Gli-1 siRNA treatment also induced apoptosis by three criteria,increase in the sub-G1 cell cycle fraction,nuclear condensation,a morphologic change typical of apoptosis,and activation of caspase-3. Gli-1 siRNA was also able to down-regulate Bcl-2. However,Gli-1 siRNA resulted in no significant changes in Bcl-xl,Bax,Bad,and Bid. Furthermore,Gli-1 siRNA increased the cytotoxic effect of 5-Fu on Huh7 cell. CONCLUSION: Down-regulation of Bcl-2 plays an important role in apoptosis induced by Gli-1 siRNA in HCC cells. Combination Gli-1 siRNA with chemotherapeutic drug could represent a more promising strategy against HCC. The effects of the strategies need further investigation in vivo and may have potential clinical application.
文摘Interleukin-15 （IL-15） is essential for the survival of memory CD8^＋ and CD4^＋ T cell subsets, and natural killer and natural killer T cells. Here, we describe a hitherto unreported role of IL-15 in regulating homoeostasis of naive CD4^＋ T cells. Adoptive transfer of splenocytes from non-obese diabetic （NOD） mice results in increased homeostatic expansion of T cells in lymphopenic NOD.scid.II15^-/- mice when compared to NOD.scid recipients. The increased accumulation of CD4^＋ T cells is also observed in NOD.II15^-/- mice, indicating that IL-15-dependent regulation also occurs in the absence of lymphopenia. NOD.scid mice lacking the I L- 15Ra chain, but not those lacking the common gamma chain, also show increased accumulation of CD4^＋ T cells. These findings indicate that the IL-15-mediated regulation occurs directly on CD4^＋ T cells and requires trans-presentation of IL-15. CD4^＋ T cells expanding in the absence of IL-15 signaling do not acquire the characteristics of classical regulatory T cells. Rather, CD4^＋ T cells expanding in the absence of IL-15 show impaired antigen-induced activation and IFN-7 production. Based on these findings, we propose that the IL-15-dependent regulation of the naive CD4^＋ T-cell compartment may represent an additional layer of control to thwart potentially autoreactive cells that escape central tolerance, while permitting the expansion of memory T cells.
