Histone methylation is an important epigenetic phenomenon that participates in a diverse array of cellular processes and has been found to be associated with cancer. Recent identification of several histone demethylas...Histone methylation is an important epigenetic phenomenon that participates in a diverse array of cellular processes and has been found to be associated with cancer. Recent identification of several histone demethylases has proved that histone methylation is a reversible process. Through a candidate approach, we have biochemically identified JMJD3 as an H3K27 demethylase. Transfection of JMJD3 into HeLa cells caused a specific reduction oftrimethyl H3K27, but had no effect on di-and monomethyl H3K27, or histone lysine methylations on H3K4 and H3K9. The enzymatic activity requires the JmjC domain and the conserved histidine that has been suggested to be important for a cofactor binding. In vitro biochemical experiments demonstrated that JMJD3 directly catalyzes the demethylation. In addition, we found that JMJD3 is upregulated in prostate cancer, and its expression is higher in metastatic prostate cancer. Thus, we identified JMJD3 as a demethylase capable of removing the trimethyl group from histone H3 lysine 27 and upregulated in prostate cancer.展开更多
目的:探讨组蛋白去甲基化酶JMJD3(jumonji domain-containing protein 3)对弥漫性大B细胞淋巴瘤(diffuse large B-cell lymphoma,DLBCL)细胞干性的影响。方法:利用TCGA数据库中DLBCL患者的临床资料,分析JMJD3的表达水平与DLBCL患者总生...目的:探讨组蛋白去甲基化酶JMJD3(jumonji domain-containing protein 3)对弥漫性大B细胞淋巴瘤(diffuse large B-cell lymphoma,DLBCL)细胞干性的影响。方法:利用TCGA数据库中DLBCL患者的临床资料,分析JMJD3的表达水平与DLBCL患者总生存率的关系。应用脂质体转染方法分别将对照质粒(pCMV)和JMJD3表达质粒(pCMV-JMJD3)转染到ABC和GCB亚型DLBCL细胞中,用RT-PCR和qPCR检测转染细胞中JMJD3、ALDH1、OCT4和SOX2 mRNA表达水平,用流式细胞术检测细胞中ALDH1酶活性,用Western blotting检测细胞中OCT4和SOX2蛋白的表达水平。通过基因集富集分析法(gene set enrichment analysis,GSEA)分析高表达JMJD3的DLBCL患者的基因集富集情况。结果:患者预后分析结果显示,高表达水平的JMJD3与DLBCL患者的不良预后有关(P<0.05),但多因素分析结果显示JMJD3的表达水平不是DLBCL患者预后的独立影响因素(均P>0.05)。pCMV-JMJD3转染后细胞中JMJD3表达显著增加,同时导致DLBCL细胞中ALDH1 mRNA水平和酶活性以及OCT4和SOX2 mRNA和蛋白的表达水平均明显升高(P<0.05或P<0.01)。GSEA分析结果显示,高表达JMJD3的DLBCL患者样本富集于Wnt/β-catenin信号通路基因集(P<0.05)。结论:JMJD3具有促进DLBCL细胞干性的作用,其可能是DLBCL患者潜在的治疗靶点。展开更多
文摘Histone methylation is an important epigenetic phenomenon that participates in a diverse array of cellular processes and has been found to be associated with cancer. Recent identification of several histone demethylases has proved that histone methylation is a reversible process. Through a candidate approach, we have biochemically identified JMJD3 as an H3K27 demethylase. Transfection of JMJD3 into HeLa cells caused a specific reduction oftrimethyl H3K27, but had no effect on di-and monomethyl H3K27, or histone lysine methylations on H3K4 and H3K9. The enzymatic activity requires the JmjC domain and the conserved histidine that has been suggested to be important for a cofactor binding. In vitro biochemical experiments demonstrated that JMJD3 directly catalyzes the demethylation. In addition, we found that JMJD3 is upregulated in prostate cancer, and its expression is higher in metastatic prostate cancer. Thus, we identified JMJD3 as a demethylase capable of removing the trimethyl group from histone H3 lysine 27 and upregulated in prostate cancer.
文摘目的:探讨组蛋白去甲基化酶JMJD3(jumonji domain-containing protein 3)对弥漫性大B细胞淋巴瘤(diffuse large B-cell lymphoma,DLBCL)细胞干性的影响。方法:利用TCGA数据库中DLBCL患者的临床资料,分析JMJD3的表达水平与DLBCL患者总生存率的关系。应用脂质体转染方法分别将对照质粒(pCMV)和JMJD3表达质粒(pCMV-JMJD3)转染到ABC和GCB亚型DLBCL细胞中,用RT-PCR和qPCR检测转染细胞中JMJD3、ALDH1、OCT4和SOX2 mRNA表达水平,用流式细胞术检测细胞中ALDH1酶活性,用Western blotting检测细胞中OCT4和SOX2蛋白的表达水平。通过基因集富集分析法(gene set enrichment analysis,GSEA)分析高表达JMJD3的DLBCL患者的基因集富集情况。结果:患者预后分析结果显示,高表达水平的JMJD3与DLBCL患者的不良预后有关(P<0.05),但多因素分析结果显示JMJD3的表达水平不是DLBCL患者预后的独立影响因素(均P>0.05)。pCMV-JMJD3转染后细胞中JMJD3表达显著增加,同时导致DLBCL细胞中ALDH1 mRNA水平和酶活性以及OCT4和SOX2 mRNA和蛋白的表达水平均明显升高(P<0.05或P<0.01)。GSEA分析结果显示,高表达JMJD3的DLBCL患者样本富集于Wnt/β-catenin信号通路基因集(P<0.05)。结论:JMJD3具有促进DLBCL细胞干性的作用,其可能是DLBCL患者潜在的治疗靶点。
