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
心血管疾病(cardiovascular diseases)一直以来都是我国乃至全球疾病负担的主要原因,其生存率低,发病率一直呈现上升趋势[1]。据推测,我国目前心血管疾病患者高达3亿,导致的死亡人数约占全国死亡人数的40%,有数据显示,我国每年因心血管...心血管疾病(cardiovascular diseases)一直以来都是我国乃至全球疾病负担的主要原因,其生存率低,发病率一直呈现上升趋势[1]。据推测,我国目前心血管疾病患者高达3亿,导致的死亡人数约占全国死亡人数的40%,有数据显示,我国每年因心血管疾病产生的费用高达1700亿元,给医疗卫生保健资源带来了极大的负担[2-3]。心血管疾病涉及冠心病、心律失常、高血压、心肌病和心力衰竭等,虽然临床表现存在差异,但在发病机制中仍有许多相似之处。溴结构域和额外终端域(bromodomain and extra-terminal domain,BET)家族蛋白是一种表观遗传调控蛋白,由含溴结构域蛋白2(bromodomain-containing protein 2,BRD2)、BRD3、BRD4和睾丸特异性含溴结构域蛋白(testis-specific bromodomain-containing protein,BRDT)组成[4]。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.
文摘心血管疾病(cardiovascular diseases)一直以来都是我国乃至全球疾病负担的主要原因,其生存率低,发病率一直呈现上升趋势[1]。据推测,我国目前心血管疾病患者高达3亿,导致的死亡人数约占全国死亡人数的40%,有数据显示,我国每年因心血管疾病产生的费用高达1700亿元,给医疗卫生保健资源带来了极大的负担[2-3]。心血管疾病涉及冠心病、心律失常、高血压、心肌病和心力衰竭等,虽然临床表现存在差异,但在发病机制中仍有许多相似之处。溴结构域和额外终端域(bromodomain and extra-terminal domain,BET)家族蛋白是一种表观遗传调控蛋白,由含溴结构域蛋白2(bromodomain-containing protein 2,BRD2)、BRD3、BRD4和睾丸特异性含溴结构域蛋白(testis-specific bromodomain-containing protein,BRDT)组成[4]。
