Elevated expression of heat shock protein 90 （HSP90） has been found in kidneys and serum of systemic lupus erythematosus （SLE） patients and MRLIMp-FasIprIFasJpr（MRLIIpr） autoimmune mice. We investigated if inhib...Elevated expression of heat shock protein 90 （HSP90） has been found in kidneys and serum of systemic lupus erythematosus （SLE） patients and MRLIMp-FasIprIFasJpr（MRLIIpr） autoimmune mice. We investigated if inhibition of HSP90 would reduce disease in MRL/ Ipr mice. In vitro, pretreatment of mesangial cells with HSP90 inhibitor Geldanamycin prior to immune-stimulation showed reduced expression of IL-6, IL-12 and NO. In vivo, we found HSP90 expression was elevated in MRL/Ipr kidneys when compared to C57BL/6 mice and MRIJIpr mice treated with HSP90 inhibitor 17-DMAG. MRIJIpr mice treated with 17-DMAG showed decreased proteinuria and reduced serum anti-dsDNA antibody production. Glomerulonephritis and glomerular IgG and C3 were not significantly affected by administration of 17-DMAG in MRIJIpr. 17-DMAG increased CD8＋ T cells, reduced double-negative T cells, decreased the CD4/CD8 ratio and reduced follicular B cells. These studies suggest that HSP90 may play a role in regulating T-cell differentiation and activation and that HSP90 inhibition may reduce inflammation in lupus.展开更多
The AhR binds to contain ligands, such as 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin, 3-methylcholantrene, or β-naphthoflavone. The activation mechanism of AhR is not yet fully understood, but it is known that AhR associ...The AhR binds to contain ligands, such as 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin, 3-methylcholantrene, or β-naphthoflavone. The activation mechanism of AhR is not yet fully understood, but it is known that AhR associates with the molecular chaperone HSP90 in the cytoplasm. There are a few reports about the association or dissociation of AhR and HSP90, and which domain of HSP90 binds to AhR. We reported the association and activation mechanisms between HSP90 and AhR-PAS or AhR-bHLH. In the current study, we found that cisplatin inhibits the AhR activation. Although ATP and 17-DMAG have no effect on the dissociation of HSP90 from AhR, some contents of HSP90 were dissociated from AhR in the presence of cisplatin. We could detect the increase of CYP1A in the presence of 3-MC. On the contrary, the induction of CYP1A1 was inhibited in the presence of cisplatin. We couldn’t detect AhR in the HeLa cell soluble fraction in the presence of 50 μM cisplatin. In the presence of MG-132, we could detect AhR. These results suggested that AhR was dissociated from the HSP90 chaperone complex and processed during the protein proteasome degradation system in the presence of cisplatin.展开更多
目的:研究阿螺旋霉素[17-(dimethylaminoethylamino)-17-demethoxygeldanamycin hydrochloride,17-DMAG]在葡聚糖硫酸钠(dextran sulphate sodium,DSS)诱导的小鼠溃疡性结肠炎治疗中的作用.方法:C57BL/6小鼠随机分为正常对照组、DSS模...目的:研究阿螺旋霉素[17-(dimethylaminoethylamino)-17-demethoxygeldanamycin hydrochloride,17-DMAG]在葡聚糖硫酸钠(dextran sulphate sodium,DSS)诱导的小鼠溃疡性结肠炎治疗中的作用.方法:C57BL/6小鼠随机分为正常对照组、DSS模型组、磷酸盐缓冲液(phosphate buffer,P B S)治疗组以及17-D M A G治疗组.采用3%D S S连续饮入以复制溃疡性结肠炎小鼠模型.对结肠炎模型小鼠每日腹腔注射17-DMAG[10 mg/(kg?d)]或同体积PBS.观察小鼠体质量、疾病活动度、单位长度结肠质量、结肠病理损伤程度及结肠上皮细胞凋亡情况,以评价17-DMAG对小鼠溃疡性结肠炎病程发展的影响.结果:3%DSS连续饮入5 d后,模型组小鼠较正常对照组小鼠体质量减轻,疾病活动度、单位肠道结肠重量、结肠病理评分及结肠上皮细胞凋亡增加.与PBS治疗组相比,17-DMAG治疗5 d后,结肠炎小鼠体质量降低程度(90.9%±7.78%vs 81%±5.44%,P<0.05)及疾病活动度显著改善(1.8±0.84 vs 4.7±1.21,P<0.05),单位长度结肠质量(4.43 mg/mm±0.16 mg/mm vs 5.71 mg/mm±0.56 mg/mm,P<0.01)及结肠病理评分降低(4.6±1.30 vs 7.4±0.30,P<0.01),结肠上皮细胞凋亡数目(33.2±5.50vs 62.6±9.81,P<0.01)显著减少.结论:17-DMAG可减轻DSS诱导的小鼠溃疡性结肠炎,其可能通过抑制结肠上皮细胞的凋亡而发挥作用.展开更多
Heat shock protein(HSP)90 plays a crucial role in correcting the misfolded three-dimensional structure of proteins,assisting them in folding into proper conformations.HSP90 is critical in maintaining the normal functi...Heat shock protein(HSP)90 plays a crucial role in correcting the misfolded three-dimensional structure of proteins,assisting them in folding into proper conformations.HSP90 is critical in maintaining the normal functions of various proteins within cells,as essential factors for cellular homeostasis.Contrastingly,HSP90 simultaneously supports the maturation of cancer-related proteins,including mesenchymal epithelial transition factor(MET)within tumor cells.All osteosarcoma cell lines had elevated MET expression in the cDNA array in our possession.MET,a tyrosine kinase receptor,promotes proliferation and an anti-apoptotic state through the activation of the MET pathway constructed by HSP90.In this study,we treated osteosarcoma cells with an HSP90 inhibitor,17-demethoxygeldanamycin hydrochloride(17-DMAG),and assessed the changes in the MET signaling pathway and also the antitumor effect of the drug.The cell cycle in osteosarcoma cells administered 17-DMAG was found to be halted at the G2/M phase.Additionally,treatment with 17-DMAG inhibited cell proliferation and induced apoptosis.Inhibition of tumor cell proliferation was also observed in an in vivo model system,mice that were treated with 17-DMAG.Based on the results of this study,we were able to confirm that 17-DMAG promotes inhibition of osteosarcoma cell proliferation and induction of apoptosis by inhibition of MET,a protein highly expressed in osteosarcoma cells.This approach may be useful for the establishment of a new treatment strategy for patients resistant to the standard treatment for osteosarcoma.展开更多
文摘Elevated expression of heat shock protein 90 （HSP90） has been found in kidneys and serum of systemic lupus erythematosus （SLE） patients and MRLIMp-FasIprIFasJpr（MRLIIpr） autoimmune mice. We investigated if inhibition of HSP90 would reduce disease in MRL/ Ipr mice. In vitro, pretreatment of mesangial cells with HSP90 inhibitor Geldanamycin prior to immune-stimulation showed reduced expression of IL-6, IL-12 and NO. In vivo, we found HSP90 expression was elevated in MRL/Ipr kidneys when compared to C57BL/6 mice and MRIJIpr mice treated with HSP90 inhibitor 17-DMAG. MRIJIpr mice treated with 17-DMAG showed decreased proteinuria and reduced serum anti-dsDNA antibody production. Glomerulonephritis and glomerular IgG and C3 were not significantly affected by administration of 17-DMAG in MRIJIpr. 17-DMAG increased CD8＋ T cells, reduced double-negative T cells, decreased the CD4/CD8 ratio and reduced follicular B cells. These studies suggest that HSP90 may play a role in regulating T-cell differentiation and activation and that HSP90 inhibition may reduce inflammation in lupus.
文摘The AhR binds to contain ligands, such as 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin, 3-methylcholantrene, or β-naphthoflavone. The activation mechanism of AhR is not yet fully understood, but it is known that AhR associates with the molecular chaperone HSP90 in the cytoplasm. There are a few reports about the association or dissociation of AhR and HSP90, and which domain of HSP90 binds to AhR. We reported the association and activation mechanisms between HSP90 and AhR-PAS or AhR-bHLH. In the current study, we found that cisplatin inhibits the AhR activation. Although ATP and 17-DMAG have no effect on the dissociation of HSP90 from AhR, some contents of HSP90 were dissociated from AhR in the presence of cisplatin. We could detect the increase of CYP1A in the presence of 3-MC. On the contrary, the induction of CYP1A1 was inhibited in the presence of cisplatin. We couldn’t detect AhR in the HeLa cell soluble fraction in the presence of 50 μM cisplatin. In the presence of MG-132, we could detect AhR. These results suggested that AhR was dissociated from the HSP90 chaperone complex and processed during the protein proteasome degradation system in the presence of cisplatin.
文摘目的:研究阿螺旋霉素[17-(dimethylaminoethylamino)-17-demethoxygeldanamycin hydrochloride,17-DMAG]在葡聚糖硫酸钠(dextran sulphate sodium,DSS)诱导的小鼠溃疡性结肠炎治疗中的作用.方法:C57BL/6小鼠随机分为正常对照组、DSS模型组、磷酸盐缓冲液(phosphate buffer,P B S)治疗组以及17-D M A G治疗组.采用3%D S S连续饮入以复制溃疡性结肠炎小鼠模型.对结肠炎模型小鼠每日腹腔注射17-DMAG[10 mg/(kg?d)]或同体积PBS.观察小鼠体质量、疾病活动度、单位长度结肠质量、结肠病理损伤程度及结肠上皮细胞凋亡情况,以评价17-DMAG对小鼠溃疡性结肠炎病程发展的影响.结果:3%DSS连续饮入5 d后,模型组小鼠较正常对照组小鼠体质量减轻,疾病活动度、单位肠道结肠重量、结肠病理评分及结肠上皮细胞凋亡增加.与PBS治疗组相比,17-DMAG治疗5 d后,结肠炎小鼠体质量降低程度(90.9%±7.78%vs 81%±5.44%,P<0.05)及疾病活动度显著改善(1.8±0.84 vs 4.7±1.21,P<0.05),单位长度结肠质量(4.43 mg/mm±0.16 mg/mm vs 5.71 mg/mm±0.56 mg/mm,P<0.01)及结肠病理评分降低(4.6±1.30 vs 7.4±0.30,P<0.01),结肠上皮细胞凋亡数目(33.2±5.50vs 62.6±9.81,P<0.01)显著减少.结论:17-DMAG可减轻DSS诱导的小鼠溃疡性结肠炎,其可能通过抑制结肠上皮细胞的凋亡而发挥作用.
基金supported in part by the fund of National Cancer Center Research and Development(26-A-4)the Grants-in-Aid for Scientific Research(Nos.15K10451,16K10866 and 16K20063)from Japan Society for the Promotion of Science.
文摘Heat shock protein(HSP)90 plays a crucial role in correcting the misfolded three-dimensional structure of proteins,assisting them in folding into proper conformations.HSP90 is critical in maintaining the normal functions of various proteins within cells,as essential factors for cellular homeostasis.Contrastingly,HSP90 simultaneously supports the maturation of cancer-related proteins,including mesenchymal epithelial transition factor(MET)within tumor cells.All osteosarcoma cell lines had elevated MET expression in the cDNA array in our possession.MET,a tyrosine kinase receptor,promotes proliferation and an anti-apoptotic state through the activation of the MET pathway constructed by HSP90.In this study,we treated osteosarcoma cells with an HSP90 inhibitor,17-demethoxygeldanamycin hydrochloride(17-DMAG),and assessed the changes in the MET signaling pathway and also the antitumor effect of the drug.The cell cycle in osteosarcoma cells administered 17-DMAG was found to be halted at the G2/M phase.Additionally,treatment with 17-DMAG inhibited cell proliferation and induced apoptosis.Inhibition of tumor cell proliferation was also observed in an in vivo model system,mice that were treated with 17-DMAG.Based on the results of this study,we were able to confirm that 17-DMAG promotes inhibition of osteosarcoma cell proliferation and induction of apoptosis by inhibition of MET,a protein highly expressed in osteosarcoma cells.This approach may be useful for the establishment of a new treatment strategy for patients resistant to the standard treatment for osteosarcoma.
