PDF(Pubmed)
Abstract：
BACKGROUND: ZNF384-fusion (Z-fusion) genes were recently identified in B-cell acute lymphoblastic leukemia (B-ALL) and are frequent in Japanese adult patients. The frequency is about 20% in those with Philadelphia chromosome-negative B-ALL. ZNF384 is a transcription factor and Z-fusion proteins have increased transcriptional activity; however, the detailed mechanisms of leukemogenesis of Z-fusion proteins have yet to be clarified.
METHODS: We established three transfectants of cell lines expressing different types of Z-fusion proteins, and analyzed their gene expression profile (GEP) by RNA-seq. We also analyzed the GEP of clinical ALL samples using our previous RNA-seq data of 323 Japanese ALL patients. We selected upregulated genes in both Z-fusion gene-expressing transfectants and Z-fusion gene-positive ALL samples, and investigated the binding of Z-fusion proteins to regulatory regions of the candidate genes by ChIP-qPCR.
RESULTS: We selected six commonly upregulated genes. After the investigation by ChIP-qPCR, we finally identified CREB5 and RGS1 as direct and common target genes. RGS1 is an inhibitor of CXCL12-CXCR4 signaling that is required for the homing of hematopoietic progenitor cells to the bone marrow microenvironment and development of B cells. Consistent with this, Z-fusion gene transfectants showed impaired migration toward CXCL12.
CONCLUSIONS: We identified CREB5 and RGS1 as direct and common transcriptional targets of Z-fusion proteins. The present results provide novel insight into the aberrant transcriptional regulation by Z-fusion proteins.
METHODS: We established three transfectants of cell lines expressing different types of Z-fusion proteins, and analyzed their gene expression profile (GEP) by RNA-seq. We also analyzed the GEP of clinical ALL samples using our previous RNA-seq data of 323 Japanese ALL patients. We selected upregulated genes in both Z-fusion gene-expressing transfectants and Z-fusion gene-positive ALL samples, and investigated the binding of Z-fusion proteins to regulatory regions of the candidate genes by ChIP-qPCR.
RESULTS: We selected six commonly upregulated genes. After the investigation by ChIP-qPCR, we finally identified CREB5 and RGS1 as direct and common target genes. RGS1 is an inhibitor of CXCL12-CXCR4 signaling that is required for the homing of hematopoietic progenitor cells to the bone marrow microenvironment and development of B cells. Consistent with this, Z-fusion gene transfectants showed impaired migration toward CXCL12.
CONCLUSIONS: We identified CREB5 and RGS1 as direct and common transcriptional targets of Z-fusion proteins. The present results provide novel insight into the aberrant transcriptional regulation by Z-fusion proteins.
摘要：
背景：最近在B细胞急性淋巴细胞白血病（B-ALL）中发现了ZNF384融合（Z融合）基因，并且在日本成年患者中很常见。在费城染色体阴性B-ALL的患者中，频率约为20％。ZNF384是一种转录因子，Z-融合蛋白的转录活性增加；然而，Z融合蛋白白血病发生的详细机制尚未阐明。
方法：我们建立了三种表达不同类型Z-融合蛋白的细胞系的转染子，并通过RNA-seq分析其基因表达谱(GEP)。我们还使用我们先前的323名日本ALL患者的RNA-seq数据分析了临床ALL样品的GEP。我们选择了表达Z融合基因的转染子和Z融合基因阳性ALL样品中的上调基因，并通过ChIP-qPCR研究了Z融合蛋白与候选基因调控区的结合。
结果：我们选择了6个常见的上调基因。经过ChIP-qPCR的调查，我们最终确定CREB5和RGS1为直接和共同的靶基因。RGS1是CXCL12-CXCR4信号传导的抑制剂，是造血祖细胞归巢到骨髓微环境和B细胞发育所必需的。与此一致，Z-融合基因转染子显示向CXCL12的迁移受损。
结论：我们确定CREB5和RGS1是Z-融合蛋白的直接和共同的转录靶标。本结果为Z-融合蛋白的异常转录调控提供了新的见解。
方法：我们建立了三种表达不同类型Z-融合蛋白的细胞系的转染子，并通过RNA-seq分析其基因表达谱(GEP)。我们还使用我们先前的323名日本ALL患者的RNA-seq数据分析了临床ALL样品的GEP。我们选择了表达Z融合基因的转染子和Z融合基因阳性ALL样品中的上调基因，并通过ChIP-qPCR研究了Z融合蛋白与候选基因调控区的结合。
结果：我们选择了6个常见的上调基因。经过ChIP-qPCR的调查，我们最终确定CREB5和RGS1为直接和共同的靶基因。RGS1是CXCL12-CXCR4信号传导的抑制剂，是造血祖细胞归巢到骨髓微环境和B细胞发育所必需的。与此一致，Z-融合基因转染子显示向CXCL12的迁移受损。
结论：我们确定CREB5和RGS1是Z-融合蛋白的直接和共同的转录靶标。本结果为Z-融合蛋白的异常转录调控提供了新的见解。
