Objective:To investigate the effects and mechanisms of tumor suppressor gene PTEN on the induction of anoikis of human bladder transitional carcinoma cells BIU-87.Methods:BIU-87 cells were transfected with GFP plasmid...Objective:To investigate the effects and mechanisms of tumor suppressor gene PTEN on the induction of anoikis of human bladder transitional carcinoma cells BIU-87.Methods:BIU-87 cells were transfected with GFP plasmids containing wild-type PTEN or phosphatase inactivating mutant PTEN(C124A-PTEN)in vitro.The PTEN expression and the phosphorylation levels of focal adhesion kinase(FAK)and protein kinase B(PKB/Akt)were detected by Western blotting.Flow cytometry assay and laser scanning confocal microscopy were used to analyze apoptosis in adherent and non-adherent cells.Results: Compared with the control group,PTEN expression in the cells transfected with wild-type PTEN increased to 210%–260%, while the phosphorylation level of FAK and Akt decreased 59%(P<0.01)and 89%(P<0.01),respectively.And the anoikis percentage increased from 8.32±0.57%to 37.62±2.12%.In the cells transfected with C124A-PTEN,neither the phos- phorylation of FAK and Akt nor the anoikis percentage had obviously changed,although the PTEN expression enhanced remarkably in comparison with the control.Conclusion:Through its phosphatase activity,tumor suppressor gene PTEN can suppress the phosphorylation of FAK and Akt,and induce anoikis in human bladder transitional carcinoma cells BIU-87.展开更多
The expression of CH50 polypoptide in bladder cancer cell line BIU-87 and the effects on the invasion ability of BIU-87 were investigated. The eukaryotic expressing vector pCH510 of polypeptide CH50 was introduced int...The expression of CH50 polypoptide in bladder cancer cell line BIU-87 and the effects on the invasion ability of BIU-87 were investigated. The eukaryotic expressing vector pCH510 of polypeptide CH50 was introduced into BIU-87 cells by gene transfection in vitro. The expression of CH50 polypeptide was detected by using immunohistochemical S-P method. The expression of the transfected gene was identified by RT-PCR. Cell invasion assay kit was applied to detect the effect of CH50 polypeptide on the invasion ability of BIU-87. The results showed that the BIU-87 cells transfected with pCH510 could express the CH50 polypeptide, while in the control group, no CH50 polypeptide was detectable. In the transfection group, the invasion ability of BIU-87 in vitro was lower than in control group (P<0.05). It was concluded that CH50 polypeptide was successfully expressed in BIU-87 cells by gene transfection, by which the in vitro invasion ability of BIU-87 was inhibited.展开更多
The expression of different vascular endothelial growth factor (VEGF) genes was studied in glioma U87 cells with endoplasmic reticulum–nuclei-1 (ERN1) loss of function and its regulation by hypoxia and glutamine or g...The expression of different vascular endothelial growth factor (VEGF) genes was studied in glioma U87 cells with endoplasmic reticulum–nuclei-1 (ERN1) loss of function and its regulation by hypoxia and glutamine or glucose deprivation conditions as model of ischemia. The blockade of function of the ERN1 enzyme, which is a major sensor of endoplasmic reticulum stress, leads to a decrease of the VEGFA, VEGFB and VEGFC mRNA expression level. The level of VEGFA proteins also decreases at this experimental condition in the cytosolic fraction, but increases in the nuclear fraction. Hypoxia does not affect VEGFC and increases the expression level of VEGFA and VEGFB mRNA in both used cell types, however, the change was much less profound in cells with suppressed function of ERN1. The expression level of VEGFC mRNA decreases in both used cell types in glutamine deprivation condition, however, the change was more profound in control glioma cells. At the same time, the expression level of VEGFA mRNA increases and VEGFB—decreases in gluta-mine deprivation condition in control glioma cells only. Exposure of glioma cells to glucose deprivation condition increases VEGFB mRNA expression level in both used cell types;however, VEGFA—in control glioma cells only and VEGFC—in cells with ERN1 signaling enzyme loss of function only. Thus, the results of this study clearly demonstrated the down-regulation of the expression of all three VEGF genes in glioma cells with ERN1 loss of function which correlates to the suppressed angiogenesis and proliferation rate of these cells. Moreover, the effect of hy-poxia and glutamine or glucose deprivation condition on the expression level of all VEGF genes is different and mainly depends on ERN1 signaling enzyme function.展开更多
We have studied the expression of a subset of genes encoding important tumor growth related factors in U87 glioma cells with IRE1 (inositol requiring enzyme-1) knockdown as well as their hypoxic regulation. It was sho...We have studied the expression of a subset of genes encoding important tumor growth related factors in U87 glioma cells with IRE1 (inositol requiring enzyme-1) knockdown as well as their hypoxic regulation. It was shown that the expression levels of activating transcription factor 6 (ATF6), clusterin (CLU), adhesion G protein-coupled receptor E5 (ADGRE5), transglutaminase?2, C polypeptide (TGM2), leukemia inhibitory factor (LIF), phosphoserine aminotransferase 1 (PSAT1), glyoxalase I (GLO1) and tetraspanin 13 (TSPAN13) are significantly down-regulated in glioma cells with the knockdown of IRE1 signaling enzyme. It was also shown that in glioma cells subjected to hypoxia, the expression levels of PSAT1, TSPAN13, EIF2AK3, and TGM2 genes were up-regulated, whereas the expression of ATF6 gene was down-regulated. At the same time, the expression levels of LIF, CLU, and ADGRE5 genes did not change in response to hypoxic treatment.?Furthermore, inhibition of IRE1, a key effector of an unfolded protein response pathway, modified the effect of hypoxia on the expression of most studied genes. Present study demonstrates that IRE1 knockdown down-regulated the expression of most studied genes and modified their hypoxic regulation and that these changes possibly contributed to the suppression of glioma growth in cells without IRE1 signaling enzyme function.展开更多
目的:探讨CUG连接蛋白1(CUG-binding protein 1,CUGBP1)在膀胱癌组织中的表达及其表达对膀胱癌BIU-87细胞株增殖及迁移能力的影响。方法:采用免疫组化及Western blot检测65例膀胱癌及相应的癌旁正常组织中CUGBP1的表达,并探讨CUGBP1表...目的:探讨CUG连接蛋白1(CUG-binding protein 1,CUGBP1)在膀胱癌组织中的表达及其表达对膀胱癌BIU-87细胞株增殖及迁移能力的影响。方法:采用免疫组化及Western blot检测65例膀胱癌及相应的癌旁正常组织中CUGBP1的表达,并探讨CUGBP1表达与膀胱癌患者临床病理特征的关系。同时,采用siR NA特性干扰片段下调CUGBP1在膀胱癌细胞株BIU-87中的表达,探讨CUGBP1下调对细胞增殖及侵袭能力的影响。结果:免疫组化结果显示CUGBP1在膀胱癌组织中的阳性表达率为58.5%,高于癌旁正常组织(9.2%),差异具有统计学意义(P<0.01);Western blot结果也显示CUGBP1在膀胱癌组织中的表达高于癌旁正常组织。同时,CUGBP1在膀胱癌组织中的表达与淋巴结转移、TNM分期及分化程度有关(P<0.05)。此外,BIU-87细胞株中CUGBP1表达明显下调后,细胞的增殖及侵袭能力均明显下降(P<0.05)。结论:CUGBP1表达与膀胱癌的形成相关,其表达下调可明显抑制细胞增殖及侵袭。展开更多
基金a grant from the National Natural Science Foundation ofChina(No.30271300).
文摘Objective:To investigate the effects and mechanisms of tumor suppressor gene PTEN on the induction of anoikis of human bladder transitional carcinoma cells BIU-87.Methods:BIU-87 cells were transfected with GFP plasmids containing wild-type PTEN or phosphatase inactivating mutant PTEN(C124A-PTEN)in vitro.The PTEN expression and the phosphorylation levels of focal adhesion kinase(FAK)and protein kinase B(PKB/Akt)were detected by Western blotting.Flow cytometry assay and laser scanning confocal microscopy were used to analyze apoptosis in adherent and non-adherent cells.Results: Compared with the control group,PTEN expression in the cells transfected with wild-type PTEN increased to 210%–260%, while the phosphorylation level of FAK and Akt decreased 59%(P<0.01)and 89%(P<0.01),respectively.And the anoikis percentage increased from 8.32±0.57%to 37.62±2.12%.In the cells transfected with C124A-PTEN,neither the phos- phorylation of FAK and Akt nor the anoikis percentage had obviously changed,although the PTEN expression enhanced remarkably in comparison with the control.Conclusion:Through its phosphatase activity,tumor suppressor gene PTEN can suppress the phosphorylation of FAK and Akt,and induce anoikis in human bladder transitional carcinoma cells BIU-87.
文摘The expression of CH50 polypoptide in bladder cancer cell line BIU-87 and the effects on the invasion ability of BIU-87 were investigated. The eukaryotic expressing vector pCH510 of polypeptide CH50 was introduced into BIU-87 cells by gene transfection in vitro. The expression of CH50 polypeptide was detected by using immunohistochemical S-P method. The expression of the transfected gene was identified by RT-PCR. Cell invasion assay kit was applied to detect the effect of CH50 polypeptide on the invasion ability of BIU-87. The results showed that the BIU-87 cells transfected with pCH510 could express the CH50 polypeptide, while in the control group, no CH50 polypeptide was detectable. In the transfection group, the invasion ability of BIU-87 in vitro was lower than in control group (P<0.05). It was concluded that CH50 polypeptide was successfully expressed in BIU-87 cells by gene transfection, by which the in vitro invasion ability of BIU-87 was inhibited.
文摘The expression of different vascular endothelial growth factor (VEGF) genes was studied in glioma U87 cells with endoplasmic reticulum–nuclei-1 (ERN1) loss of function and its regulation by hypoxia and glutamine or glucose deprivation conditions as model of ischemia. The blockade of function of the ERN1 enzyme, which is a major sensor of endoplasmic reticulum stress, leads to a decrease of the VEGFA, VEGFB and VEGFC mRNA expression level. The level of VEGFA proteins also decreases at this experimental condition in the cytosolic fraction, but increases in the nuclear fraction. Hypoxia does not affect VEGFC and increases the expression level of VEGFA and VEGFB mRNA in both used cell types, however, the change was much less profound in cells with suppressed function of ERN1. The expression level of VEGFC mRNA decreases in both used cell types in glutamine deprivation condition, however, the change was more profound in control glioma cells. At the same time, the expression level of VEGFA mRNA increases and VEGFB—decreases in gluta-mine deprivation condition in control glioma cells only. Exposure of glioma cells to glucose deprivation condition increases VEGFB mRNA expression level in both used cell types;however, VEGFA—in control glioma cells only and VEGFC—in cells with ERN1 signaling enzyme loss of function only. Thus, the results of this study clearly demonstrated the down-regulation of the expression of all three VEGF genes in glioma cells with ERN1 loss of function which correlates to the suppressed angiogenesis and proliferation rate of these cells. Moreover, the effect of hy-poxia and glutamine or glucose deprivation condition on the expression level of all VEGF genes is different and mainly depends on ERN1 signaling enzyme function.
文摘We have studied the expression of a subset of genes encoding important tumor growth related factors in U87 glioma cells with IRE1 (inositol requiring enzyme-1) knockdown as well as their hypoxic regulation. It was shown that the expression levels of activating transcription factor 6 (ATF6), clusterin (CLU), adhesion G protein-coupled receptor E5 (ADGRE5), transglutaminase?2, C polypeptide (TGM2), leukemia inhibitory factor (LIF), phosphoserine aminotransferase 1 (PSAT1), glyoxalase I (GLO1) and tetraspanin 13 (TSPAN13) are significantly down-regulated in glioma cells with the knockdown of IRE1 signaling enzyme. It was also shown that in glioma cells subjected to hypoxia, the expression levels of PSAT1, TSPAN13, EIF2AK3, and TGM2 genes were up-regulated, whereas the expression of ATF6 gene was down-regulated. At the same time, the expression levels of LIF, CLU, and ADGRE5 genes did not change in response to hypoxic treatment.?Furthermore, inhibition of IRE1, a key effector of an unfolded protein response pathway, modified the effect of hypoxia on the expression of most studied genes. Present study demonstrates that IRE1 knockdown down-regulated the expression of most studied genes and modified their hypoxic regulation and that these changes possibly contributed to the suppression of glioma growth in cells without IRE1 signaling enzyme function.