目的:探讨抑制哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)信号通路在高体积分数氧(高氧)致SD幼鼠肺损伤时对磷酸化AKT1(p-AKT1)分子的影响和意义。方法:72只SD幼鼠(3周龄)随机分为空气+生理盐水组、高氧+生理盐水组...目的:探讨抑制哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)信号通路在高体积分数氧(高氧)致SD幼鼠肺损伤时对磷酸化AKT1(p-AKT1)分子的影响和意义。方法:72只SD幼鼠(3周龄)随机分为空气+生理盐水组、高氧+生理盐水组、高氧+OSI-027组及高氧+雷帕霉素组(n=18),分别构建动物模型。高氧选择90%氧气持续干预,生理盐水、OSI-027和雷帕霉素干预分别在观察期第1、3、6、8、10和13天时经腹腔注射给药。在造模第3、7和14天时取各组幼鼠进行体重测量、肺湿干重比(wet/drg weight ratio,W/D)计算、肺组织病理学检查、肺泡间隔宽度测定和肺损伤评分,肺组织免疫组化和Western blot检测磷酸化S6K1(p-S6K1)和p-AKT1的分布与水平。结果:与空气组比较,高氧组幼鼠体重明显下降(P<0.05),肺损伤急性期肺W/D增高(P<0.05),肺泡间隔宽度及肺损伤评分明显增加(P<0.05),肺组织p-S6K1阳性细胞增多(P<0.05),肺组织p-AKT1阳性细胞减少(P<0.05),p-S6K1蛋白显著升高(P<0.01),p-AKT1蛋白明显减低(P<0.01);与高氧组比较,高氧+OSI-027组的肺组织损伤减轻,肺组织p-S6K1阳性细胞减少(P<0.05),p-AKT1阳性细胞增多(P<0.05),p-S6K1蛋白水平显著降低(P<0.05),p-AKT1蛋白水平增加(P<0.05);高氧+雷帕霉素组的肺损伤进一步加重(P<0.05),p-S6K1阳性细胞减少(P<0.05),p-AKT1阳性细胞增加(P<0.05),p-S6K1蛋白水平显著降低(P<0.05),p-AKT1蛋白水平显著增加(P<0.05)。与高氧+雷帕霉素组比较,高氧+OSI-027组的肺组织损伤减轻(P<0.05),肺组织p-AKT1阳性细胞减少(P<0.05),p-AKT1蛋白水平降低(P<0.05)。结论:p-AKT1参与了高氧肺损伤的发生发展,其调控机制可能与抑制mTOR信号通路的活化有关。高氧肺损伤时,p-AKT1蛋白水平下降,mTOR抑制剂能增加p-AKT1蛋白水平,但只有mTORC1/2双重抑制剂OSI-027能减轻高氧所致SD幼鼠的肺损伤及纤维化。展开更多
目的:探讨新疆维吾尔族和汉族乳腺癌组织中哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)及其下游分子4EBP1和S6K1的表达差异。方法:选取2005-03-01-2009-09-30新疆医科大学附属肿瘤医院的维吾尔族和汉族女性浸润性乳腺...目的:探讨新疆维吾尔族和汉族乳腺癌组织中哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)及其下游分子4EBP1和S6K1的表达差异。方法:选取2005-03-01-2009-09-30新疆医科大学附属肿瘤医院的维吾尔族和汉族女性浸润性乳腺癌患者285例,使用免疫组化方法检测磷酸化mTOR及其下游分子4EBP1和S6K1的表达状况;分别选取2012-01-01-2012-06-30新疆医科大学附属肿瘤医院63例维、汉新鲜乳腺癌和癌旁组织样本,使用荧光定量RT-PCR法检测mTOR及其下游分子4EBP1和S6K1的mRNA表达状况。结果:免疫组化结果显示,维吾尔族和汉族p-mTOR在乳腺癌组织中的阳性表达率分别为77.1%和67.4%(P=0.067),在癌旁组织中的阳性表达率分别为57.6%和61.7%(P=0.485);p-4EBP1在癌组织中的阳性表达率分别为31.9%和20.0%(P=0.020),在乳腺癌旁组织中的阳性表达率分别是4.9%和12.1%(P=0.029);p-S6K1在癌组织中的阳性表达率分别为41.0%和43.3%(P=0.695),在乳腺癌旁组织中的阳性表达率分别为14.0%和22.7%,P=0.054;荧光定量RT-PCR结果显示,维、汉乳腺癌组织中mTOR mRNA相对定量结果差异有统计学意义,P=0.045;4EBP1和S6K1mRNA相对定量结果差异无统计学意义,P值分别为0.128和0.404。结论:mTOR信号通路中p-4EBP1的表达水平存在维、汉民族的差异,为研究维、汉不同民族之间乳腺癌差异及个体化治疗提供了进一步研究方向。mTOR及其下游分子mRNA表达水平与磷酸化蛋白的表达并不完全一致,提示蛋白表达的调控位点可能位于转录后水平。展开更多
Histone deacetylase 1(HDAC1)is an important epigenetic controller involvedin transcriptional regulation throughmodification of chromatin structure.Genetic and epigenetic changes and deregulation of signal transduction...Histone deacetylase 1(HDAC1)is an important epigenetic controller involvedin transcriptional regulation throughmodification of chromatin structure.Genetic and epigenetic changes and deregulation of signal transduction pathways have been implicated in the development of breast cancer.Downregulation of estrogen receptor a(ERa)expression is one of the mechanisms behind the acquisition of endocrine resistance.Sustained and increased hormone and growth factor receptor signaling in breast cancer cells contribute to resistance to endocrine therapy.Both HDACs and the PI3K/mTOR signaling pathway are becoming promising targets in breast cancer,reversing also acquired hormone resistance.Here we show how mitogens,activating the PI3K/mTOR pathway,trigger the phosphorylation of HDAC1 in breast cancer cells,which is completely dependent on the activity of the p70 S6 kinase(S6K1).Our findings show that S6K1,overexpressed in many breast cancers,controls HDAC1-dependent transcriptional regulation of ERa levels upon mitogenic stimuli,controlling HDAC1 recruitment to the ERa promoter.Furthermore,cell treatment with both mTOR and HDACs inhibitors shows an additive effect in inhibiting breast cancer proliferation.This confirms the novel cross-talk between the HDAC1 and PI3K pathways with clinical implications towards the treatment of this malignant disease.展开更多
文摘目的:探讨新疆维吾尔族和汉族乳腺癌组织中哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)及其下游分子4EBP1和S6K1的表达差异。方法:选取2005-03-01-2009-09-30新疆医科大学附属肿瘤医院的维吾尔族和汉族女性浸润性乳腺癌患者285例,使用免疫组化方法检测磷酸化mTOR及其下游分子4EBP1和S6K1的表达状况;分别选取2012-01-01-2012-06-30新疆医科大学附属肿瘤医院63例维、汉新鲜乳腺癌和癌旁组织样本,使用荧光定量RT-PCR法检测mTOR及其下游分子4EBP1和S6K1的mRNA表达状况。结果:免疫组化结果显示,维吾尔族和汉族p-mTOR在乳腺癌组织中的阳性表达率分别为77.1%和67.4%(P=0.067),在癌旁组织中的阳性表达率分别为57.6%和61.7%(P=0.485);p-4EBP1在癌组织中的阳性表达率分别为31.9%和20.0%(P=0.020),在乳腺癌旁组织中的阳性表达率分别是4.9%和12.1%(P=0.029);p-S6K1在癌组织中的阳性表达率分别为41.0%和43.3%(P=0.695),在乳腺癌旁组织中的阳性表达率分别为14.0%和22.7%,P=0.054;荧光定量RT-PCR结果显示,维、汉乳腺癌组织中mTOR mRNA相对定量结果差异有统计学意义,P=0.045;4EBP1和S6K1mRNA相对定量结果差异无统计学意义,P值分别为0.128和0.404。结论:mTOR信号通路中p-4EBP1的表达水平存在维、汉民族的差异,为研究维、汉不同民族之间乳腺癌差异及个体化治疗提供了进一步研究方向。mTOR及其下游分子mRNA表达水平与磷酸化蛋白的表达并不完全一致,提示蛋白表达的调控位点可能位于转录后水平。
基金This work was supported by grants from Associazione Italiana per la Ricerca sul Cancro to S.C.(AIRC IG5732,AIRC IG12075)S.Ci.was supported by a fellowship from Fondazione Umberto Veronesi(FUV).
文摘Histone deacetylase 1(HDAC1)is an important epigenetic controller involvedin transcriptional regulation throughmodification of chromatin structure.Genetic and epigenetic changes and deregulation of signal transduction pathways have been implicated in the development of breast cancer.Downregulation of estrogen receptor a(ERa)expression is one of the mechanisms behind the acquisition of endocrine resistance.Sustained and increased hormone and growth factor receptor signaling in breast cancer cells contribute to resistance to endocrine therapy.Both HDACs and the PI3K/mTOR signaling pathway are becoming promising targets in breast cancer,reversing also acquired hormone resistance.Here we show how mitogens,activating the PI3K/mTOR pathway,trigger the phosphorylation of HDAC1 in breast cancer cells,which is completely dependent on the activity of the p70 S6 kinase(S6K1).Our findings show that S6K1,overexpressed in many breast cancers,controls HDAC1-dependent transcriptional regulation of ERa levels upon mitogenic stimuli,controlling HDAC1 recruitment to the ERa promoter.Furthermore,cell treatment with both mTOR and HDACs inhibitors shows an additive effect in inhibiting breast cancer proliferation.This confirms the novel cross-talk between the HDAC1 and PI3K pathways with clinical implications towards the treatment of this malignant disease.
