Introduction:Hepatocellular carcinoma(HCC),a prevalent malignancy,poses significant challenges with high tumor heterogeneity and poor prognosis.MicroRNAs(miRNAs)play a pivotal role in hepatocarcinogenesis.Although abno...Introduction:Hepatocellular carcinoma(HCC),a prevalent malignancy,poses significant challenges with high tumor heterogeneity and poor prognosis.MicroRNAs(miRNAs)play a pivotal role in hepatocarcinogenesis.Although abnormalities in microRNA-557(miR-557)expression have been implicated in various cancer types,its role in HCC remains unclear.Therefore,there is a need to explore the function of microRNA-557 in HCC.Methods:Candidate miRNAs were identified through screening in GSE108724 and GSE20077.Real-time PCR was employed to analyze the expression level of miR-557 in hepatoma cell lines and tissues.Cell viability and migration assays were applied to assess the impact of miR-557 on HCC cell lines.Furthermore,the miR-557 target was predicted through three algorithms(Targetscan,miRWalk,and miRanda),and this was confirmed through luciferase assay and Western blotting.Results:In this study,miR-557 was identified in two datasets and expressed at a low level in both hepatoma cell lines and tissues.Notably,high expression of miR-557 in HCC cells inhibited oncogenesis.Conversely,low expression of miR-557 enhanced tumor proliferation and migration.Polycomb chromobox 4(CBX4)was identified as a direct target of miR-557.Silencing CBX4 influenced the functional impact of miR-557 on HCC cell migration.Conclusion:Taken together,our study contributed to elucidating the hepatoma molecular heterogeneity and provided novel insights into miR-557 role and its target CBX4 in HCC,suggesting its potential as a future effectively druggable target for HCC intervention.展开更多
We recently report that the expression of polycomb chromobox 4(Cbx4)is significantly correlated with the overall survival of a great cohort of hepatocellular carcinoma(HCC)patients and it enhances hypoxia-induced vasc...We recently report that the expression of polycomb chromobox 4(Cbx4)is significantly correlated with the overall survival of a great cohort of hepatocellular carcinoma(HCC)patients and it enhances hypoxia-induced vascular endothelial growth factor(VEGF)expression and angiogenesis in HCC cells through enhancing sumoylation of hypoxia inducible factor-1alpha(HIF-1α).Here we continue to investigate the potential effects of Cbx4 on the migration and metastasis of the metastatic HCC cell line MHCC97L.Our results show that Cbx4 overexpression in the cell line increases the in vitro vessel formation of vascular endothelial cells in its SUMO interaction motifs-dependent manner,and promotes the in vitro migration of the cancer cell,which can be effectively abrogated by anti-VEGF antibody.Although Cbx4 expression does not impact the in vitro growth of MHCC97L cells,it still promotes the progression and metastasis of orthotopically transplanted tumors in nude mice.These results further support the role of Cbx4 as a SUMO E3 ligase in the progression and metastasis of HCC.展开更多
目的·探究染色质组织调节框同源蛋白8(chromobox protein homolog 8,CBX8)在前列腺癌中的生物学功能,并通过转录组及表观修饰分析揭示CBX8在前列腺癌转移中的作用机制。方法·利用cBioPortal数据库对癌症基因组图谱(The Cancer...目的·探究染色质组织调节框同源蛋白8(chromobox protein homolog 8,CBX8)在前列腺癌中的生物学功能,并通过转录组及表观修饰分析揭示CBX8在前列腺癌转移中的作用机制。方法·利用cBioPortal数据库对癌症基因组图谱(The Cancer Genome Atlas,TCGA)中前列腺腺癌(prostate adenocarcinoma,PRAD)患者样本数据集进行CBX家族蛋白mRNA表达分析。采用短发夹RNA技术敲低DU145前列腺癌细胞系中的CBX8,通过CCK-8和Transwell实验检测细胞增殖和侵袭水平的变化。使用RNA转录组测序(RNA-seq)分析敲低CBX8后影响的差异表达基因。对这些差异表达基因进行基因集富集分析(Gene Set Enrichment Analysis,GSEA)、基因本体论(Gene Ontology,GO)功能分析以及京都基因和基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)信号通路富集分析。通过染色质免疫沉淀测序(ChIPseq)观察和测定敲低CBX8后基因组H3K27me3甲基化水平的变化。结果·根据对TCGA-PRAD患者样本数据的分析,发现CBX8 mRNA在前列腺癌中高表达。在前列腺癌细胞系DU145中敲低CBX8后,细胞的增殖能力没有显著变化(P>0.05),但其侵袭能力却显著提高(P<0.05)。RNA-seq分析显示CBX8敲低导致750个基因表达上调,951个基因表达下调;其中,与多种肿瘤转移有关的支链氨基酸转氨酶1(branched-chain-amino-acid aminotransferase 1,BCAT1)在敲除CBX8后表达明显上升。GSEA显示表达水平受影响的基因与多梳蛋白复合体1(polycomb repressive complex 1,PRC1)的功能有关。同时,通过GO和KEGG信号通路富集分析发现受影响的生物过程包括转运RNA(transfer RNA,tRNA)氨酰化、DNA复制、氨酰基-tRNA连接酶活性变化以及钙黏蛋白的结合等;特别是在GO功能分析的细胞组分方面富集了与肿瘤转移有关的细胞-基底连接相关基因。利用ChIP-seq对表观修饰的研究显示,在敲低CBX8后全基因组的H3K27me3水平有所下降;并鉴定了97个位于CBX8敲低后转录上调基因附近的位点,其中包括BCAT1转录起始位点。结论·CBX8在人前列腺癌中高表达。CBX8具有抑制肿瘤细胞侵袭的功能。其机制可能是CBX8/PRC1复合体结合于BCAT1转录起始位点并抑制BCAT1转录。展开更多
色素框同源蛋白8(chromobox protein homolog 8,CBX8)是PcG家族蛋白PRC1复合体的核心组成部分,在细胞增殖、衰老、维持干细胞自我更新和全能性及肿瘤发生中发挥重要作用.目前研究发现CBX8在多种恶性肿瘤中表达增高,并与肿瘤的进展及预...色素框同源蛋白8(chromobox protein homolog 8,CBX8)是PcG家族蛋白PRC1复合体的核心组成部分,在细胞增殖、衰老、维持干细胞自我更新和全能性及肿瘤发生中发挥重要作用.目前研究发现CBX8在多种恶性肿瘤中表达增高,并与肿瘤的进展及预后密切相关,已成为当前肿瘤领域的研究热点.本文就当前CBX8在肿瘤中的研究作一综述.展开更多
BACKGROUND Pancreatic cancer(PC)is one of the most lethal malignancies worldwide.It is known that the proliferation of PC cells is a critical process in the disease.Previous studies have failed to identify the key gen...BACKGROUND Pancreatic cancer(PC)is one of the most lethal malignancies worldwide.It is known that the proliferation of PC cells is a critical process in the disease.Previous studies have failed to identify the key genes associated with PC cell proliferation,using bioinformatic analysis,genome-wide association studies,and candidate gene testing.AIM To investigate the function of the chromobox 8(CBX8)/receptor substrate 1(IRS1)/AKT axis in PC.METHODS A genome-wide CRISPR-Cas9 screening was performed to select genes that could facilitate PC cell proliferation.Quantitative reverse transcription-polymerase chain reaction was used to detect the expression of CBX8 in PC tissues and cells.The regulatory roles of CBX8 in cell proliferation,migration,and invasion were verified by in vivo and in vitro functional assays.RESULTS CBX8 was upregulated in PC tissues and shown to drive PC cell proliferation.Higher expression of CBX8 was correlated with worse outcomes of PC patients from two independent cohorts comprising a total of 116 cases.CBX8 was also proved to serve as a promising therapeutic target for a PC xenograft model.We demonstrated that hypoxia-inducible factor(HIF)-1a induced CBX8 transcription by binding to the promoter of CBX8.CBX8 efficiently activated the PI3K/AKT signaling by upregulating insulin IRS1.CONCLUSION CBX8 is a key gene regulated by HIF-1α,and activates the IRS1/AKT pathway,which suggests that targeting CBX8 may be a promising therapeutic strategy for PC.展开更多
CBX蛋白(Chromobox protein homolog)是多梳蛋白家族(Polycomb group proteins,Pc G)的重要成员,多梳蛋白家族是一种表观遗传调控复合物,以聚合转录抑制复合体PRCs的形式存在,可以通过修饰染色质对靶基因进行转录抑制,在调控细胞分化、...CBX蛋白(Chromobox protein homolog)是多梳蛋白家族(Polycomb group proteins,Pc G)的重要成员,多梳蛋白家族是一种表观遗传调控复合物,以聚合转录抑制复合体PRCs的形式存在,可以通过修饰染色质对靶基因进行转录抑制,在调控细胞分化、衰老、死亡和肿瘤发生、转移中发挥着重要作用。CBX蛋白家族是经典型PRC1的重要成员,包括5个成员,CBX2、CBX4、CBX6、CBX7和CBX8,越来越多的证据表明它在肿瘤发生、发展中扮演重要角色。本篇综述阐述了目前关于CBX家族成员在肿瘤中的研究进展。展开更多
文摘Introduction:Hepatocellular carcinoma(HCC),a prevalent malignancy,poses significant challenges with high tumor heterogeneity and poor prognosis.MicroRNAs(miRNAs)play a pivotal role in hepatocarcinogenesis.Although abnormalities in microRNA-557(miR-557)expression have been implicated in various cancer types,its role in HCC remains unclear.Therefore,there is a need to explore the function of microRNA-557 in HCC.Methods:Candidate miRNAs were identified through screening in GSE108724 and GSE20077.Real-time PCR was employed to analyze the expression level of miR-557 in hepatoma cell lines and tissues.Cell viability and migration assays were applied to assess the impact of miR-557 on HCC cell lines.Furthermore,the miR-557 target was predicted through three algorithms(Targetscan,miRWalk,and miRanda),and this was confirmed through luciferase assay and Western blotting.Results:In this study,miR-557 was identified in two datasets and expressed at a low level in both hepatoma cell lines and tissues.Notably,high expression of miR-557 in HCC cells inhibited oncogenesis.Conversely,low expression of miR-557 enhanced tumor proliferation and migration.Polycomb chromobox 4(CBX4)was identified as a direct target of miR-557.Silencing CBX4 influenced the functional impact of miR-557 on HCC cell migration.Conclusion:Taken together,our study contributed to elucidating the hepatoma molecular heterogeneity and provided novel insights into miR-557 role and its target CBX4 in HCC,suggesting its potential as a future effectively druggable target for HCC intervention.
基金supported by the National Natural Science Foundation of China (91213304,31101044)Shanghai Science and Technology Committee (11JC1406800)Shanghai Committee of Education
文摘We recently report that the expression of polycomb chromobox 4(Cbx4)is significantly correlated with the overall survival of a great cohort of hepatocellular carcinoma(HCC)patients and it enhances hypoxia-induced vascular endothelial growth factor(VEGF)expression and angiogenesis in HCC cells through enhancing sumoylation of hypoxia inducible factor-1alpha(HIF-1α).Here we continue to investigate the potential effects of Cbx4 on the migration and metastasis of the metastatic HCC cell line MHCC97L.Our results show that Cbx4 overexpression in the cell line increases the in vitro vessel formation of vascular endothelial cells in its SUMO interaction motifs-dependent manner,and promotes the in vitro migration of the cancer cell,which can be effectively abrogated by anti-VEGF antibody.Although Cbx4 expression does not impact the in vitro growth of MHCC97L cells,it still promotes the progression and metastasis of orthotopically transplanted tumors in nude mice.These results further support the role of Cbx4 as a SUMO E3 ligase in the progression and metastasis of HCC.
文摘目的·探究染色质组织调节框同源蛋白8(chromobox protein homolog 8,CBX8)在前列腺癌中的生物学功能,并通过转录组及表观修饰分析揭示CBX8在前列腺癌转移中的作用机制。方法·利用cBioPortal数据库对癌症基因组图谱(The Cancer Genome Atlas,TCGA)中前列腺腺癌(prostate adenocarcinoma,PRAD)患者样本数据集进行CBX家族蛋白mRNA表达分析。采用短发夹RNA技术敲低DU145前列腺癌细胞系中的CBX8,通过CCK-8和Transwell实验检测细胞增殖和侵袭水平的变化。使用RNA转录组测序(RNA-seq)分析敲低CBX8后影响的差异表达基因。对这些差异表达基因进行基因集富集分析(Gene Set Enrichment Analysis,GSEA)、基因本体论(Gene Ontology,GO)功能分析以及京都基因和基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)信号通路富集分析。通过染色质免疫沉淀测序(ChIPseq)观察和测定敲低CBX8后基因组H3K27me3甲基化水平的变化。结果·根据对TCGA-PRAD患者样本数据的分析,发现CBX8 mRNA在前列腺癌中高表达。在前列腺癌细胞系DU145中敲低CBX8后,细胞的增殖能力没有显著变化(P>0.05),但其侵袭能力却显著提高(P<0.05)。RNA-seq分析显示CBX8敲低导致750个基因表达上调,951个基因表达下调;其中,与多种肿瘤转移有关的支链氨基酸转氨酶1(branched-chain-amino-acid aminotransferase 1,BCAT1)在敲除CBX8后表达明显上升。GSEA显示表达水平受影响的基因与多梳蛋白复合体1(polycomb repressive complex 1,PRC1)的功能有关。同时,通过GO和KEGG信号通路富集分析发现受影响的生物过程包括转运RNA(transfer RNA,tRNA)氨酰化、DNA复制、氨酰基-tRNA连接酶活性变化以及钙黏蛋白的结合等;特别是在GO功能分析的细胞组分方面富集了与肿瘤转移有关的细胞-基底连接相关基因。利用ChIP-seq对表观修饰的研究显示,在敲低CBX8后全基因组的H3K27me3水平有所下降;并鉴定了97个位于CBX8敲低后转录上调基因附近的位点,其中包括BCAT1转录起始位点。结论·CBX8在人前列腺癌中高表达。CBX8具有抑制肿瘤细胞侵袭的功能。其机制可能是CBX8/PRC1复合体结合于BCAT1转录起始位点并抑制BCAT1转录。
文摘色素框同源蛋白8(chromobox protein homolog 8,CBX8)是PcG家族蛋白PRC1复合体的核心组成部分,在细胞增殖、衰老、维持干细胞自我更新和全能性及肿瘤发生中发挥重要作用.目前研究发现CBX8在多种恶性肿瘤中表达增高,并与肿瘤的进展及预后密切相关,已成为当前肿瘤领域的研究热点.本文就当前CBX8在肿瘤中的研究作一综述.
基金Supported by National Natural Science Foundation of China(General Program),No.81974372(to Qiu ZJ).
文摘BACKGROUND Pancreatic cancer(PC)is one of the most lethal malignancies worldwide.It is known that the proliferation of PC cells is a critical process in the disease.Previous studies have failed to identify the key genes associated with PC cell proliferation,using bioinformatic analysis,genome-wide association studies,and candidate gene testing.AIM To investigate the function of the chromobox 8(CBX8)/receptor substrate 1(IRS1)/AKT axis in PC.METHODS A genome-wide CRISPR-Cas9 screening was performed to select genes that could facilitate PC cell proliferation.Quantitative reverse transcription-polymerase chain reaction was used to detect the expression of CBX8 in PC tissues and cells.The regulatory roles of CBX8 in cell proliferation,migration,and invasion were verified by in vivo and in vitro functional assays.RESULTS CBX8 was upregulated in PC tissues and shown to drive PC cell proliferation.Higher expression of CBX8 was correlated with worse outcomes of PC patients from two independent cohorts comprising a total of 116 cases.CBX8 was also proved to serve as a promising therapeutic target for a PC xenograft model.We demonstrated that hypoxia-inducible factor(HIF)-1a induced CBX8 transcription by binding to the promoter of CBX8.CBX8 efficiently activated the PI3K/AKT signaling by upregulating insulin IRS1.CONCLUSION CBX8 is a key gene regulated by HIF-1α,and activates the IRS1/AKT pathway,which suggests that targeting CBX8 may be a promising therapeutic strategy for PC.
文摘CBX蛋白(Chromobox protein homolog)是多梳蛋白家族(Polycomb group proteins,Pc G)的重要成员,多梳蛋白家族是一种表观遗传调控复合物,以聚合转录抑制复合体PRCs的形式存在,可以通过修饰染色质对靶基因进行转录抑制,在调控细胞分化、衰老、死亡和肿瘤发生、转移中发挥着重要作用。CBX蛋白家族是经典型PRC1的重要成员,包括5个成员,CBX2、CBX4、CBX6、CBX7和CBX8,越来越多的证据表明它在肿瘤发生、发展中扮演重要角色。本篇综述阐述了目前关于CBX家族成员在肿瘤中的研究进展。
