AIM: To evaluate the influence of hydrogen peroxide (H2O2) on mouse photoreceptor-derived 661W cell survival and to determine the effect of PD98059, an inhibitor for MEK1 (the direct upstream activator of ERK1/2), and...AIM: To evaluate the influence of hydrogen peroxide (H2O2) on mouse photoreceptor-derived 661W cell survival and to determine the effect of PD98059, an inhibitor for MEK1 (the direct upstream activator of ERK1/2), and S3I201, a STAT3-specific inhibitor on 661W cell survival after H2O2 exposure. METHODS: The mouse photoreceptor-derived 661W cells were cultured. 661W cells were treated for 12 hours with different concentrations (0, 0.25, 0.50, 0.75, 1mmol/L) of H2O2 and cell viability was determined by 3- (4, 5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide) (MTT) assay. 661W cells were treated with different concentrations H2O2 (0, 5, 10, 50, 500, 1000 mu mol/L) for 15 minutes or 1mmol/L H2O2 for different time points (0,5,10,15,30 minutes), and p-Tyr705-STAT3, STAT3, Phospho-p44/42 MAPK (Thr202/Tyr204), ERK1/2 were surveyed by immunoblot analysis. After treatment with 50 mu mol/L PD98059, or S3I201 for 1 hour, the inhibition efficiency of cell signal pathways was analyzed by immunoblot analysis and the effects of inhibitors on cell viability were determined by MTT. RESULTS: After treating with different concentrations of H2O2 for 12 hours, the cell viability of 661W cells decreased in concentration-dependent manner (P<0.05). Moreover, H2O2 induced phosphorylation of ERK1/2 and STAT3 in 661W cells (P <0.05). After pretreatment with 50 mu mol/L PD98059 or S3I201 for 1 hour, H2O2-induced phosphorylation of ERK1/2 or STAT3 was suppressed separately (P<0.05). Using PD98059 or S3I201 to inhibit ERK1/2 or STAT3 signal pathway, the cell viability of 661W cells decreased significantly (P<0.05). CONCLUSION: We demonstrated that the exposure of 661W cells to H2O2 increased the activation of ERK1/2 and STAT3 signal pathways. Activation of these pathways is required for 661W cell survival following oxidant injury.展开更多
目的:探讨肿瘤坏死因子α(tumor necrosis factor-α,TNF-α)对人脱落乳牙牙髓干细胞(stem cells from human exfoliated deciduous teeth,SHED)骨分化能力的影响,分析ERK1/2-Runx2信号通路在该调控过程中的变化。方法:从6~8岁健康儿童...目的:探讨肿瘤坏死因子α(tumor necrosis factor-α,TNF-α)对人脱落乳牙牙髓干细胞(stem cells from human exfoliated deciduous teeth,SHED)骨分化能力的影响,分析ERK1/2-Runx2信号通路在该调控过程中的变化。方法:从6~8岁健康儿童正常乳恒牙替换即将脱落的乳切牙中分离和培养SHED,取第三代细胞,分为对照组(成骨诱导剂培养)、观察组(成骨诱导剂和TNF-α共培养)和激动剂组(成骨诱导剂、TNF-α和ERK通路激动剂共培养)。采用茜素红染色评价成骨分化功能,采用Western印迹检测SHED细胞中Osterix、OPN、ERK1/2、pERK1/2和Runx2的蛋白表达水平,应用qRT-PCR检测Osterix、OPN、ERK1/2、pERK1/2和Runx2 mRNA的表达。采用SPSS 26.0软件包对数据进行统计学分析。结果:3组细胞成骨分化能力比较结果显示,3组细胞中均可见红棕色矿化结节。3组组间相比,对照组矿化结节最多,激动剂组次之,观察组最少。与对照组相比,观察组和激动剂组的Osterix、OPN蛋白和mRNA表达水平显著下降,而激动剂组Osterix、OPN蛋白和mRNA表达水平显著高于观察组;3组细胞的ERK1/2蛋白和mRNA表达水平无显著差异,而观察组和激动剂组pERK1/2和Runx2的蛋白和mRNA表达水平显著高于对照组,激动剂组的蛋白及mRNA表达水平显著高于观察组。结论:TNF-α对SHED成骨分化具有抑制作用,该作用可能与抑制ERK1/2-Runx2信号通路有关。展开更多
Background:Magnesium cantharidate(MC)is a protein phosphatase 2A(PP2A)inhibitor antitumor drug.However,its antitumor mechanism in hepatocellular carcinoma cell(HCC)remains unclear.Methods:PP2A lentiviral vector over e...Background:Magnesium cantharidate(MC)is a protein phosphatase 2A(PP2A)inhibitor antitumor drug.However,its antitumor mechanism in hepatocellular carcinoma cell(HCC)remains unclear.Methods:PP2A lentiviral vector over expression strategy was utilized both in vivo and in vitro to explore the antitumor effect in MC and okadaic acid(OA).Tumor weight was detected in mice after MC and OA exposure.Cell proliferation,cell cycle,apoptosis rate,and western blotting were detected to explore the effects on MC and OA in human hepatocarcinoma SMMC-7721 cells.Results:In vivo results demonstrated that MC inhibited HCC progression while OA promoted tumor growth.In vitro results demonstrated that MC effectively inhibited the growth of SMMC-7721 cells by arresting the cell cycle at the G2/M phase with inhibiting Cdc25C and activating the phosphorylation of the Cdc2 protein.Flow cytometry results further showed that MC increased apoptosis.Furthermore,the expression of phosphorylated ERK1/2 was lower in the MC group but higher in the OA group.Molecular docking results showed that MC docked well with ERK1/2.Conclusions:MC inhibited HCC progression by suppressing the growth and activating the apoptosis of cancer cells and suppressing the expression of PP2A and ERK1/2.展开更多
基金National Natural Scientific Foundation of China (No. 81070752)PhD Innovation Program of Hunan Province, China (No. CX2010B106)Science and Technology Planning Project of Hunan Province, China (No. 2011wk3050)
文摘AIM: To evaluate the influence of hydrogen peroxide (H2O2) on mouse photoreceptor-derived 661W cell survival and to determine the effect of PD98059, an inhibitor for MEK1 (the direct upstream activator of ERK1/2), and S3I201, a STAT3-specific inhibitor on 661W cell survival after H2O2 exposure. METHODS: The mouse photoreceptor-derived 661W cells were cultured. 661W cells were treated for 12 hours with different concentrations (0, 0.25, 0.50, 0.75, 1mmol/L) of H2O2 and cell viability was determined by 3- (4, 5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide) (MTT) assay. 661W cells were treated with different concentrations H2O2 (0, 5, 10, 50, 500, 1000 mu mol/L) for 15 minutes or 1mmol/L H2O2 for different time points (0,5,10,15,30 minutes), and p-Tyr705-STAT3, STAT3, Phospho-p44/42 MAPK (Thr202/Tyr204), ERK1/2 were surveyed by immunoblot analysis. After treatment with 50 mu mol/L PD98059, or S3I201 for 1 hour, the inhibition efficiency of cell signal pathways was analyzed by immunoblot analysis and the effects of inhibitors on cell viability were determined by MTT. RESULTS: After treating with different concentrations of H2O2 for 12 hours, the cell viability of 661W cells decreased in concentration-dependent manner (P<0.05). Moreover, H2O2 induced phosphorylation of ERK1/2 and STAT3 in 661W cells (P <0.05). After pretreatment with 50 mu mol/L PD98059 or S3I201 for 1 hour, H2O2-induced phosphorylation of ERK1/2 or STAT3 was suppressed separately (P<0.05). Using PD98059 or S3I201 to inhibit ERK1/2 or STAT3 signal pathway, the cell viability of 661W cells decreased significantly (P<0.05). CONCLUSION: We demonstrated that the exposure of 661W cells to H2O2 increased the activation of ERK1/2 and STAT3 signal pathways. Activation of these pathways is required for 661W cell survival following oxidant injury.
基金The research was financially supported by the National Natural Science Foundation of China(no.81760746)Science and Technology Department of Zunyi city of Guizhou province of China([2020]7)Guizhou Provincial Science&Technology Program(ZK[2022]615).
文摘Background:Magnesium cantharidate(MC)is a protein phosphatase 2A(PP2A)inhibitor antitumor drug.However,its antitumor mechanism in hepatocellular carcinoma cell(HCC)remains unclear.Methods:PP2A lentiviral vector over expression strategy was utilized both in vivo and in vitro to explore the antitumor effect in MC and okadaic acid(OA).Tumor weight was detected in mice after MC and OA exposure.Cell proliferation,cell cycle,apoptosis rate,and western blotting were detected to explore the effects on MC and OA in human hepatocarcinoma SMMC-7721 cells.Results:In vivo results demonstrated that MC inhibited HCC progression while OA promoted tumor growth.In vitro results demonstrated that MC effectively inhibited the growth of SMMC-7721 cells by arresting the cell cycle at the G2/M phase with inhibiting Cdc25C and activating the phosphorylation of the Cdc2 protein.Flow cytometry results further showed that MC increased apoptosis.Furthermore,the expression of phosphorylated ERK1/2 was lower in the MC group but higher in the OA group.Molecular docking results showed that MC docked well with ERK1/2.Conclusions:MC inhibited HCC progression by suppressing the growth and activating the apoptosis of cancer cells and suppressing the expression of PP2A and ERK1/2.
