OBJECTIVE To discover a small-molecule bromodomain-containing protein 4(BRD4)inhibitor that induces AMP-activated protein kinase-modulated autophagy-associated cell death in breast cancer and exploreits potential mech...OBJECTIVE To discover a small-molecule bromodomain-containing protein 4(BRD4)inhibitor that induces AMP-activated protein kinase-modulated autophagy-associated cell death in breast cancer and exploreits potential mechanisms.METHODS BRD4 interactors were analyzed by PPI network prediction and The Cancer Genome Atlas(TCGA)analysis.The interaction between BRD4 and AMPK was confirmed by co-immunoprecipitation assay.Novel BRD4 inhibitors were designed and synthesized based upon pharmacophore analysis of BRD4(1),then screened by antiproliferative activity and Alpha Screen of BRD4(1).The selectivity of the best candidate compound 8f was validated by co-crystallization,FRET assay and co-immuno precipitation assay.The mechanisms of 8f were investigated by fluorescence microscopy,electron microscopy,Western blotting,immunocytochemistry,si RNA and GFP-m RFP-LC3 plasmid transfections,as well as immunohistochemistry and immunofluorescence.Potential mechanisms were discovered by i TRAQ-based proteomics analysis and the therapeutic effect of 8f was assessed by xenograft breast cancer mouse and zebrafish models.RESULTS We identified that BRD4 interacted with AMPK,which was remarkably downregulated in breast cancer.We next designed and synthesized 49 candidate compounds,and eventually discovered a selective small-molecule inhibitor of BRD4(8f).Subsequently,8f was discovered to induce autophagyassociated cell death(ACD)by BRD4-AMPK interaction,and thus activating AMPK-m TOR-ULK1-modulated autophagic pathway in breast cancer cells.Interestingly,the i TRAQ-based proteomics analyses revealed that 8f induced ACD pathways,involved in HMGB1,VDAC1/2 and e EF2.Moreover,8f displayed a therapeutic potential on both xenograft breast cancer mouse and zebrafish models.CONCLUSION We discovered a novel small-molecule inhibitor of BRD4 that induces BRD4-AMPK-modulated ACD in breast cancer,which may provide a candidate drug for future cancer therapy.展开更多
目的探讨程序性细胞死亡因子4(programmed cell death protein 4,PDCD4)对卵巢癌细胞生长、凋亡及磷酸化信号转导和转录激活因子3(phosphorylated signal transducer and activator of transcription 3,p-STAT3)、磷酸化p38丝裂原激活...目的探讨程序性细胞死亡因子4(programmed cell death protein 4,PDCD4)对卵巢癌细胞生长、凋亡及磷酸化信号转导和转录激活因子3(phosphorylated signal transducer and activator of transcription 3,p-STAT3)、磷酸化p38丝裂原激活蛋白激酶(phosphorylated p38 mitogen activation protein kinase,p-p38MAPK)表达的影响。方法卵巢癌细胞SKO-V3转染PDCD4过表达载体(pDsRes2-N1-PDCD4)和对照载体(pDsRes2-N1),分别记为过表达组和阴性组,同时以不转染的细胞作为对照组。以下列方法对三组细胞进行检测和比较:以实时逆转录聚合酶链反应和蛋白质印迹法检测细胞PDCD4蛋白和mRNA表达水平,以噻唑蓝比色法和细胞克隆实验检测细胞增殖能力,以流式细胞术检测细胞凋亡情况,以蛋白质印迹法检测p-p38MAPK、p-STAT3水平。结果阴性组和对照组细胞中PDCD4 mRNA和蛋白表达水平、光密度(optical density,OD)、细胞克隆形成数目、凋亡率、p-p38MAPK和p-STAT3表达水平比较均无显著差异(P_均> 0.05)。过表达组细胞中PDCD4mRNA和蛋白表达水平及细胞凋亡率均明显高于对照组和阴性组(P_均<0.01),细胞OD和克隆形成数目均明显低于对照组和阴性组(P_均<0.01)。过表达组细胞p-STAT3/STAT3比值明显低于对照组(P <0.01),p-p38MAPK/p38MAPK比值明显高于对照组(P <0.01)。结论 PDCD4抑制卵巢癌细胞生长,促进卵巢癌细胞凋亡,这可能与其抑制STAT3信号通路激活和促进p38MAPK信号通路激活有关。展开更多
目的探讨三阴性乳腺癌中程序性细胞死亡基因4(programmed cell death gene 4,PDCD4)的表达及其与患者预后的关系。方法收集广东省妇幼保健院乳腺科2007年1月至2012年12月间收治的随访资料完整的三阴性乳腺癌患者共176例,均为女性,中位年...目的探讨三阴性乳腺癌中程序性细胞死亡基因4(programmed cell death gene 4,PDCD4)的表达及其与患者预后的关系。方法收集广东省妇幼保健院乳腺科2007年1月至2012年12月间收治的随访资料完整的三阴性乳腺癌患者共176例,均为女性,中位年龄44岁。采用免疫组化方法检测PDCD4的表达;采用Kaplan-meier法对患者的无病生存及总生存情况进行分析,并运用Cox回归法探讨影响三阴性乳腺癌生存预后的因素。结果 176例患者中,PDCD4表达阳性者79例(44.8%),显著低于癌旁组织阳性表达率(90.0%,P=0.005)。PDCD4表达缺失与年龄无关(P>0.05),而与肿瘤直径、淋巴结转移个数及组织学分级相关(P<0.05),肿瘤越大(r=-0.270,P<0.001)、淋巴结转移越多(r=-0.240,P=0.001)、组织学分级越高(r=-0.206,P=0.006),PDCD4阳性表达率越低。中位随访时间42个月,单因素分析显示PDCD4表达阳性者其无病生存率及总生存率均优于表达阴性者(P<0.05)。多因素分析显示PDCD4表达、肿瘤直径及分期是影响三阴性乳腺癌预后的独立因素(P<0.05)。结论三阴性乳腺癌中PDCD4表达缺失与预后不良相关,PDCD4可作为评估三阴性乳腺癌预后的指标。展开更多
基金supported by National Natural Science Foundation of China(81473091,81673290 and U1603123)
文摘OBJECTIVE To discover a small-molecule bromodomain-containing protein 4(BRD4)inhibitor that induces AMP-activated protein kinase-modulated autophagy-associated cell death in breast cancer and exploreits potential mechanisms.METHODS BRD4 interactors were analyzed by PPI network prediction and The Cancer Genome Atlas(TCGA)analysis.The interaction between BRD4 and AMPK was confirmed by co-immunoprecipitation assay.Novel BRD4 inhibitors were designed and synthesized based upon pharmacophore analysis of BRD4(1),then screened by antiproliferative activity and Alpha Screen of BRD4(1).The selectivity of the best candidate compound 8f was validated by co-crystallization,FRET assay and co-immuno precipitation assay.The mechanisms of 8f were investigated by fluorescence microscopy,electron microscopy,Western blotting,immunocytochemistry,si RNA and GFP-m RFP-LC3 plasmid transfections,as well as immunohistochemistry and immunofluorescence.Potential mechanisms were discovered by i TRAQ-based proteomics analysis and the therapeutic effect of 8f was assessed by xenograft breast cancer mouse and zebrafish models.RESULTS We identified that BRD4 interacted with AMPK,which was remarkably downregulated in breast cancer.We next designed and synthesized 49 candidate compounds,and eventually discovered a selective small-molecule inhibitor of BRD4(8f).Subsequently,8f was discovered to induce autophagyassociated cell death(ACD)by BRD4-AMPK interaction,and thus activating AMPK-m TOR-ULK1-modulated autophagic pathway in breast cancer cells.Interestingly,the i TRAQ-based proteomics analyses revealed that 8f induced ACD pathways,involved in HMGB1,VDAC1/2 and e EF2.Moreover,8f displayed a therapeutic potential on both xenograft breast cancer mouse and zebrafish models.CONCLUSION We discovered a novel small-molecule inhibitor of BRD4 that induces BRD4-AMPK-modulated ACD in breast cancer,which may provide a candidate drug for future cancer therapy.
文摘目的探讨程序性细胞死亡因子4(programmed cell death protein 4,PDCD4)对卵巢癌细胞生长、凋亡及磷酸化信号转导和转录激活因子3(phosphorylated signal transducer and activator of transcription 3,p-STAT3)、磷酸化p38丝裂原激活蛋白激酶(phosphorylated p38 mitogen activation protein kinase,p-p38MAPK)表达的影响。方法卵巢癌细胞SKO-V3转染PDCD4过表达载体(pDsRes2-N1-PDCD4)和对照载体(pDsRes2-N1),分别记为过表达组和阴性组,同时以不转染的细胞作为对照组。以下列方法对三组细胞进行检测和比较:以实时逆转录聚合酶链反应和蛋白质印迹法检测细胞PDCD4蛋白和mRNA表达水平,以噻唑蓝比色法和细胞克隆实验检测细胞增殖能力,以流式细胞术检测细胞凋亡情况,以蛋白质印迹法检测p-p38MAPK、p-STAT3水平。结果阴性组和对照组细胞中PDCD4 mRNA和蛋白表达水平、光密度(optical density,OD)、细胞克隆形成数目、凋亡率、p-p38MAPK和p-STAT3表达水平比较均无显著差异(P_均> 0.05)。过表达组细胞中PDCD4mRNA和蛋白表达水平及细胞凋亡率均明显高于对照组和阴性组(P_均<0.01),细胞OD和克隆形成数目均明显低于对照组和阴性组(P_均<0.01)。过表达组细胞p-STAT3/STAT3比值明显低于对照组(P <0.01),p-p38MAPK/p38MAPK比值明显高于对照组(P <0.01)。结论 PDCD4抑制卵巢癌细胞生长,促进卵巢癌细胞凋亡,这可能与其抑制STAT3信号通路激活和促进p38MAPK信号通路激活有关。
基金The project supported by Foundation of Beijing University of Chinese Medicine(2009JYBZZ-2JS038),Foundation of Beijing University of Chinese Medicine(2011JYBZZ-XS037),Foundation of Beijing University of Chinese Medicine(2011JYBZZ-XS045)~~
