Proteolysis targeting chimeras（PROTACs） are bispecific molecules containing a target protein binder and a ubiquitin ligase binder connected by a linker. Recently, some heterobifunctional small molecule bromodomain-c...Proteolysis targeting chimeras（PROTACs） are bispecific molecules containing a target protein binder and a ubiquitin ligase binder connected by a linker. Recently, some heterobifunctional small molecule bromodomain-containing protein 4（BRD4） degraders based on the concept of PROTACs were designed to induce the degradation of BRD4 protein. Herein, we synthesized a new class of PROTAC BRD4 degraders. One of the most promising compound 22f exhibited robust potency of BRD4 inhibition with IC50 value of （9.4±0.6） nmol/L. Furthermore, com- pound 22f potently inhibited cell proliferation in BRD4-sensitive cell lines RS4;11 with IC50 value of （27.6±1.6） nmol/L and capable of inducing degradation of BRD4 protein at 0.5-1.0 μmol/L in the RS4;11 cells. These data establish that compound 22f is a potent and efficacious BRD4 degrader.展开更多
SWI/SNF chromatin remodelers are evolutionarily conserved multiprotein complexes that use the energy of ATP hydrolysis to change chromatin structure.A characteristic feature of SWI/SNF remodelers is the occurrence in ...SWI/SNF chromatin remodelers are evolutionarily conserved multiprotein complexes that use the energy of ATP hydrolysis to change chromatin structure.A characteristic feature of SWI/SNF remodelers is the occurrence in both the catalytic ATPase subunit and some auxiliary subunits,of bromodomains,the protein motifs capable of binding acetylated histones.Here,we report that the Arabidopsis bromodomaincontaining proteins BRD1,BRD2,and BRD13 are likely true SWI/SNF subunits that interact with the core SWI/SNF components SWI3C and SWP73B.Loss of function of each single BRD protein caused early flowering but had a negligible effect on other developmental pathways.By contrast,a brd triple mutation(brdx3)led to more pronounced developmental abnormalities,indicating functional redundancy among the BRD proteins.The brdx3 phenotypes,including hypersensitivity to abscisic acid and the gibberellin biosynthesis inhibitor paclobutrazol,resembled those of swi/snf mutants.Furthermore,the BRM protein level and occupancy at the direct target loci SCL3,ABI5,and SVP were reduced in the brdx3 mutant background.Finally,a brdx3 brm-3 quadruple mutant,in which SWI/SNF complexes were devoid of all constituent bromodomains,phenocopied a loss-of-function mutation in BRM.Taken together,our results demonstrate the relevance of BRDs as SWI/SNF subunits and suggest their cooperation with the bromodomain of BRM ATPase.展开更多
BACKGROUND Esophageal squamous cell carcinoma(ESCC),the predominant type of esophageal cancer,has a 5-year survival rate less than 20%.Although the cause of poor prognosis is the high incidence and mortality of ESCC,t...BACKGROUND Esophageal squamous cell carcinoma(ESCC),the predominant type of esophageal cancer,has a 5-year survival rate less than 20%.Although the cause of poor prognosis is the high incidence and mortality of ESCC,the high rate of metastasis after esophageal cancer surgery is the main cause of death after the surgery.Bromodomain-containing protein 4(BRD4),an epigenetic reader of chromatinacetylated histones in tumorigenesis and development,plays an essential role in regulating oncogene expression.BRD4 inhibition and BRD4 inhibition-based treatment can potentially suppress ESCC growth.However,the effects and mechanisms of action of BRD4 on ESCC cell migration remain unclear.AIM To explore the effect of BRD4 on cell migration of ESCC in vitro and its possible molecular mechanism.METHODS Human ESCC cell lines KYSE-450 and KYSE-150 were used.The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay was performed to examine cell proliferation,and the transwell migration assay was conducted to test ESCC cell migration.JQ1,a BRD4 inhibitor,was applied to cells,and BRD4 siRNA was transfected into ESCC cells to knockdown endogenous BRD4.GFP-RFP-LC3 adenovirus was infected into ESCC cells to evaluate the effect of JQ1 on autophagy.Western blotting was performed to determine the protein levels of BRD4,E-cadherin,vimentin,AMP-activated protein kinase(AMPK),and p-AMPK.RESULTS BRD4 was either downregulated by small interfering RNA or pretreated with JQ1 in ESCC cells,leading to increased tumor migration in ESCC cells in a dose-and time-dependent manner.Inhibition of BRD4 not only significantly suppressed cell proliferation but also strongly increased cell migration by inducing epithelial-mesenchymal transition(EMT).The protein expression of vimentin was increased and E-cadherin decreased in a dose-dependent manner,subsequently promoting autophagy in KYSE-450 and KYSE-150 cells.Pretreatment with JQ1,a BRD4 inhibitor,inhibited BRD4-induced LC3-II activation and upregulated AMPK phosphorylation in a dosedepend展开更多
Objective:To study the correlation of bromodomain-containing protein 4(BRD4)and S-phase kinase-associated protein 2(Skp2)expression levels in ultrasound-guided thyroid nodule fine needle aspiration biopsy tissue with ...Objective:To study the correlation of bromodomain-containing protein 4(BRD4)and S-phase kinase-associated protein 2(Skp2)expression levels in ultrasound-guided thyroid nodule fine needle aspiration biopsy tissue with the pathological features of nodules.Methods:The tissues obtained in ultrasound-guided thyroid nodule fine needle aspiration biopsy in our hospital between March 2015 and March 2018 was selected and divided into malignant group and benign group according to the pathological results,and the expression levels of BRD4,Skp2,proliferation genes and angiogenesis genes were detected.Results:The BRD4 and Skp2 mRNA expression in thyroid nodules of the malignant group were significantly higher than those of the benign group,and the BRD4 and Skp2 mRNA expression in the malignant group of thyroid nodules with TNM III-IV,capsular invasion and lymph node metastasis were significantly higher than those in the thyroid nodules with TNM I-II,without capsular invasion and without lymph node metastasis;cyclin D1(CCND1),β-catenin,proliferation cell nuclear antigen(PCNA),vascular endothelial growth factor(VEGF),endothelial cell specific molecule-1(ESM-1),Survivin and cyclooxygenase 2(COX2)mRNA expression in thyroid nodules of the malignant group were obviously higher than those of the benign group and positively correlated with BRD4 and Skp2 while cyclin G2(CCNG2)and endostatin(ES)mRNA expression were significantly lower than those of the benign group and negatively correlated with BRD4 and Skp2.Conclusion:The high expression of BRD4 and Skp2 in malignant thyroid nodules is correlated with the pathological changes and can change the expression of proliferation genes and angiogenesis genes.展开更多
含溴结构域蛋白2(bromodomain-containing protein 2,BRD2)具有两个串联的溴结构域和一个末端外结构域,是溴结构域和末端外结构域蛋白家族成员之一。BRD2蛋白能够特异性结合组蛋白乙酰化赖氨酸,参与基因的转录调控、染色质重塑和细胞增...含溴结构域蛋白2(bromodomain-containing protein 2,BRD2)具有两个串联的溴结构域和一个末端外结构域,是溴结构域和末端外结构域蛋白家族成员之一。BRD2蛋白能够特异性结合组蛋白乙酰化赖氨酸,参与基因的转录调控、染色质重塑和细胞增殖与凋亡等生物学活动。近年来研究表明,BRD2蛋白通过溴结构域和乙酰化组蛋白之间的表观遗传相互作用来调控基因转录和细胞周期、神经发育、炎症和脂肪生成,并且在肿瘤细胞增殖以及病毒感染和复制过程中也有着重要作用。该文主要从BRD2蛋白的结构特征、细胞功能和参与病毒复制的作用机制等方面进行综述,以期为深入研究BRD2蛋白的功能提供参考。展开更多
溴结构域和超末端结构域(bromodomain and extraterminal domain,Bet)家族是表观基因组的调节因子,也是肿瘤细胞生存所依赖的肿瘤相关基因表达的关键驱动因子。溴结构域蛋白4(bromodomain-containing protein 4,Brd4)是溴域和端外蛋白...溴结构域和超末端结构域(bromodomain and extraterminal domain,Bet)家族是表观基因组的调节因子,也是肿瘤细胞生存所依赖的肿瘤相关基因表达的关键驱动因子。溴结构域蛋白4(bromodomain-containing protein 4,Brd4)是溴域和端外蛋白家族中的一员,通常识别乙酰化组蛋白,并定位于目的基因的启动子或增强子区域,启动并维持肿瘤相关基因的表达。Brd4与多种转录因子调控和染色质修饰密切相关,并参与DNA损伤修复、维持端粒功能,从而维持肿瘤细胞的存活。本文围绕Brd4蛋白的结构、功能及其抑制剂在肿瘤研究中的应用进行综述。展开更多
近年来研究表明,脑胶质瘤中广泛存在表观遗传学异常现象。与基因突变不同,表观遗传学是可逆的,它可以调控胶质瘤细胞致瘤和非致瘤状态间的转换。组蛋白乙酰化是一种重要的表观遗传学修饰方式。组蛋白乙酰化阅读器——布罗莫结构域蛋白4(...近年来研究表明,脑胶质瘤中广泛存在表观遗传学异常现象。与基因突变不同,表观遗传学是可逆的,它可以调控胶质瘤细胞致瘤和非致瘤状态间的转换。组蛋白乙酰化是一种重要的表观遗传学修饰方式。组蛋白乙酰化阅读器——布罗莫结构域蛋白4(bromodomain-containing protein 4,BRD4)作为胶质瘤治疗靶点,为恢复胶质瘤细胞正常的表观遗传学状态,更有效地治疗恶性胶质瘤提供了新的研究角度[1-3]。目前研究表明,下调BRD4基因或采用BRD4选择性抑制剂JQ1,能够有效地抑制胶质母细胞瘤干细胞(glioblastoma stem cells,GSCs)增殖,促进细胞凋亡,但作用效果有一定的局限性,这提示不能被JQ1抑制的胶质瘤细胞存在其它途径维持异常的自我更新,因此BRD4抑制剂与其它药物联用治疗脑胶质瘤可能具有广阔的前景。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
胰腺癌是一种高侵袭性消化系统恶性肿瘤,严重威胁人类健康。含溴结构域的蛋白质4(bromodomaincontaining protein 4,BRD4)是溴域和外域(bromodomain and extraterminal domain,BET)蛋白家族的成员之一,胰腺癌细胞中过表达的BRD4可诱导...胰腺癌是一种高侵袭性消化系统恶性肿瘤,严重威胁人类健康。含溴结构域的蛋白质4(bromodomaincontaining protein 4,BRD4)是溴域和外域(bromodomain and extraterminal domain,BET)蛋白家族的成员之一,胰腺癌细胞中过表达的BRD4可诱导核受体亚家族5中的A组成员2(nuclear receptor subfamily 5 group A member 2,NR5A2)表达上调,并进一步增强生长分化因子15(growth differentiation factor 15,GDF15)在胰腺癌中的转录水平,促进胰腺癌细胞增殖、转移和侵袭。微RNA(miRNA)-608可以通过结合BRD4 mRNA的3'-非翻译区直接抑制BRD4的表达,从而显著增加胰腺癌的细胞凋亡;使用吉西他滨和BRD4沉默处理胰腺癌细胞时,能减少吉西他滨的耐药性,显著促进胰腺导管腺癌细胞凋亡。了解BRD4的结构构成,探究BRD4在胰腺癌细胞增殖、侵袭、转移以及癌细胞凋亡和癌细胞耐药等过程中的作用通路及临床应用,可为防治胰腺癌的发生、发展提供新思路。展开更多
文摘Proteolysis targeting chimeras（PROTACs） are bispecific molecules containing a target protein binder and a ubiquitin ligase binder connected by a linker. Recently, some heterobifunctional small molecule bromodomain-containing protein 4（BRD4） degraders based on the concept of PROTACs were designed to induce the degradation of BRD4 protein. Herein, we synthesized a new class of PROTAC BRD4 degraders. One of the most promising compound 22f exhibited robust potency of BRD4 inhibition with IC50 value of （9.4±0.6） nmol/L. Furthermore, com- pound 22f potently inhibited cell proliferation in BRD4-sensitive cell lines RS4;11 with IC50 value of （27.6±1.6） nmol/L and capable of inducing degradation of BRD4 protein at 0.5-1.0 μmol/L in the RS4;11 cells. These data establish that compound 22f is a potent and efficacious BRD4 degrader.
基金supported by grants from National Science Centre project nos.2014/15/N/NZ2/00396 to K.J.,2014/13/B/NZ1/00967 to A.J.,and 2017/26/E/NZ2/00899 to R.A.sponsored in part by the Center for Preclinical Research and Technology(CePT)+1 种基金a project co-sponsored by the European Regional Development Fund and Innovative EconomyThe National Cohesion Strategy of Poland.
文摘SWI/SNF chromatin remodelers are evolutionarily conserved multiprotein complexes that use the energy of ATP hydrolysis to change chromatin structure.A characteristic feature of SWI/SNF remodelers is the occurrence in both the catalytic ATPase subunit and some auxiliary subunits,of bromodomains,the protein motifs capable of binding acetylated histones.Here,we report that the Arabidopsis bromodomaincontaining proteins BRD1,BRD2,and BRD13 are likely true SWI/SNF subunits that interact with the core SWI/SNF components SWI3C and SWP73B.Loss of function of each single BRD protein caused early flowering but had a negligible effect on other developmental pathways.By contrast,a brd triple mutation(brdx3)led to more pronounced developmental abnormalities,indicating functional redundancy among the BRD proteins.The brdx3 phenotypes,including hypersensitivity to abscisic acid and the gibberellin biosynthesis inhibitor paclobutrazol,resembled those of swi/snf mutants.Furthermore,the BRM protein level and occupancy at the direct target loci SCL3,ABI5,and SVP were reduced in the brdx3 mutant background.Finally,a brdx3 brm-3 quadruple mutant,in which SWI/SNF complexes were devoid of all constituent bromodomains,phenocopied a loss-of-function mutation in BRM.Taken together,our results demonstrate the relevance of BRDs as SWI/SNF subunits and suggest their cooperation with the bromodomain of BRM ATPase.
基金the Key Project of Science and Technology of Xinxiang,No.GG2020027the Health Commission of Henan Province of China,No.SBGJ202102188.
文摘BACKGROUND Esophageal squamous cell carcinoma(ESCC),the predominant type of esophageal cancer,has a 5-year survival rate less than 20%.Although the cause of poor prognosis is the high incidence and mortality of ESCC,the high rate of metastasis after esophageal cancer surgery is the main cause of death after the surgery.Bromodomain-containing protein 4(BRD4),an epigenetic reader of chromatinacetylated histones in tumorigenesis and development,plays an essential role in regulating oncogene expression.BRD4 inhibition and BRD4 inhibition-based treatment can potentially suppress ESCC growth.However,the effects and mechanisms of action of BRD4 on ESCC cell migration remain unclear.AIM To explore the effect of BRD4 on cell migration of ESCC in vitro and its possible molecular mechanism.METHODS Human ESCC cell lines KYSE-450 and KYSE-150 were used.The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay was performed to examine cell proliferation,and the transwell migration assay was conducted to test ESCC cell migration.JQ1,a BRD4 inhibitor,was applied to cells,and BRD4 siRNA was transfected into ESCC cells to knockdown endogenous BRD4.GFP-RFP-LC3 adenovirus was infected into ESCC cells to evaluate the effect of JQ1 on autophagy.Western blotting was performed to determine the protein levels of BRD4,E-cadherin,vimentin,AMP-activated protein kinase(AMPK),and p-AMPK.RESULTS BRD4 was either downregulated by small interfering RNA or pretreated with JQ1 in ESCC cells,leading to increased tumor migration in ESCC cells in a dose-and time-dependent manner.Inhibition of BRD4 not only significantly suppressed cell proliferation but also strongly increased cell migration by inducing epithelial-mesenchymal transition(EMT).The protein expression of vimentin was increased and E-cadherin decreased in a dose-dependent manner,subsequently promoting autophagy in KYSE-450 and KYSE-150 cells.Pretreatment with JQ1,a BRD4 inhibitor,inhibited BRD4-induced LC3-II activation and upregulated AMPK phosphorylation in a dosedepend
基金Hubei Provincial Natural Science Foundation Project.Project No:WJ2015MB125.
文摘Objective:To study the correlation of bromodomain-containing protein 4(BRD4)and S-phase kinase-associated protein 2(Skp2)expression levels in ultrasound-guided thyroid nodule fine needle aspiration biopsy tissue with the pathological features of nodules.Methods:The tissues obtained in ultrasound-guided thyroid nodule fine needle aspiration biopsy in our hospital between March 2015 and March 2018 was selected and divided into malignant group and benign group according to the pathological results,and the expression levels of BRD4,Skp2,proliferation genes and angiogenesis genes were detected.Results:The BRD4 and Skp2 mRNA expression in thyroid nodules of the malignant group were significantly higher than those of the benign group,and the BRD4 and Skp2 mRNA expression in the malignant group of thyroid nodules with TNM III-IV,capsular invasion and lymph node metastasis were significantly higher than those in the thyroid nodules with TNM I-II,without capsular invasion and without lymph node metastasis;cyclin D1(CCND1),β-catenin,proliferation cell nuclear antigen(PCNA),vascular endothelial growth factor(VEGF),endothelial cell specific molecule-1(ESM-1),Survivin and cyclooxygenase 2(COX2)mRNA expression in thyroid nodules of the malignant group were obviously higher than those of the benign group and positively correlated with BRD4 and Skp2 while cyclin G2(CCNG2)and endostatin(ES)mRNA expression were significantly lower than those of the benign group and negatively correlated with BRD4 and Skp2.Conclusion:The high expression of BRD4 and Skp2 in malignant thyroid nodules is correlated with the pathological changes and can change the expression of proliferation genes and angiogenesis genes.
文摘含溴结构域蛋白2(bromodomain-containing protein 2,BRD2)具有两个串联的溴结构域和一个末端外结构域,是溴结构域和末端外结构域蛋白家族成员之一。BRD2蛋白能够特异性结合组蛋白乙酰化赖氨酸,参与基因的转录调控、染色质重塑和细胞增殖与凋亡等生物学活动。近年来研究表明,BRD2蛋白通过溴结构域和乙酰化组蛋白之间的表观遗传相互作用来调控基因转录和细胞周期、神经发育、炎症和脂肪生成,并且在肿瘤细胞增殖以及病毒感染和复制过程中也有着重要作用。该文主要从BRD2蛋白的结构特征、细胞功能和参与病毒复制的作用机制等方面进行综述,以期为深入研究BRD2蛋白的功能提供参考。
文摘溴结构域和超末端结构域(bromodomain and extraterminal domain,Bet)家族是表观基因组的调节因子,也是肿瘤细胞生存所依赖的肿瘤相关基因表达的关键驱动因子。溴结构域蛋白4(bromodomain-containing protein 4,Brd4)是溴域和端外蛋白家族中的一员,通常识别乙酰化组蛋白,并定位于目的基因的启动子或增强子区域,启动并维持肿瘤相关基因的表达。Brd4与多种转录因子调控和染色质修饰密切相关,并参与DNA损伤修复、维持端粒功能,从而维持肿瘤细胞的存活。本文围绕Brd4蛋白的结构、功能及其抑制剂在肿瘤研究中的应用进行综述。
文摘近年来研究表明,脑胶质瘤中广泛存在表观遗传学异常现象。与基因突变不同,表观遗传学是可逆的,它可以调控胶质瘤细胞致瘤和非致瘤状态间的转换。组蛋白乙酰化是一种重要的表观遗传学修饰方式。组蛋白乙酰化阅读器——布罗莫结构域蛋白4(bromodomain-containing protein 4,BRD4)作为胶质瘤治疗靶点,为恢复胶质瘤细胞正常的表观遗传学状态,更有效地治疗恶性胶质瘤提供了新的研究角度[1-3]。目前研究表明,下调BRD4基因或采用BRD4选择性抑制剂JQ1,能够有效地抑制胶质母细胞瘤干细胞(glioblastoma stem cells,GSCs)增殖,促进细胞凋亡,但作用效果有一定的局限性,这提示不能被JQ1抑制的胶质瘤细胞存在其它途径维持异常的自我更新,因此BRD4抑制剂与其它药物联用治疗脑胶质瘤可能具有广阔的前景。
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]。
文摘胰腺癌是一种高侵袭性消化系统恶性肿瘤,严重威胁人类健康。含溴结构域的蛋白质4(bromodomaincontaining protein 4,BRD4)是溴域和外域(bromodomain and extraterminal domain,BET)蛋白家族的成员之一,胰腺癌细胞中过表达的BRD4可诱导核受体亚家族5中的A组成员2(nuclear receptor subfamily 5 group A member 2,NR5A2)表达上调,并进一步增强生长分化因子15(growth differentiation factor 15,GDF15)在胰腺癌中的转录水平,促进胰腺癌细胞增殖、转移和侵袭。微RNA(miRNA)-608可以通过结合BRD4 mRNA的3'-非翻译区直接抑制BRD4的表达,从而显著增加胰腺癌的细胞凋亡;使用吉西他滨和BRD4沉默处理胰腺癌细胞时,能减少吉西他滨的耐药性,显著促进胰腺导管腺癌细胞凋亡。了解BRD4的结构构成,探究BRD4在胰腺癌细胞增殖、侵袭、转移以及癌细胞凋亡和癌细胞耐药等过程中的作用通路及临床应用,可为防治胰腺癌的发生、发展提供新思路。
