MOLECULAR PATHOGENESIS OF CHROMOSOME 16 INVERSION INHUMA

16号染色体反转INHUMA的分子发病机制

• 批准号: 6829439
• 负责人: PU PAUL LIU
• 金额: --
• 依托单位: NATIONAL HUMAN GENOME RESEARCH INSTITUTE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6829439
• 关键词: acute myelogenous leukemia; arthritis; carcinogenesis; chromosome inversion; disease /disorder model; embryonic stem cell; fusion gene; genetic promoter element; genetic regulation; human genetic material tag; human tissue; laboratory mouse; microarray technology; molecular oncology; molecular pathology; myosins; neoplasm /cancer genetics; oncogenes; polymerase chain reaction; serial analysis of gene expression; transcription factor; transfection; tumor suppressor genes; yeast two hybrid system

Chromosome 16 inversion, inv(16), is one of the most common chromosome abnormalities in human acute myeloid leukemia (AML). A fusion gene between the core binding factor B (CBFB) gene and the myosin heavy chain 11 (MYH11) gene is generated by this inversion. CBFB encodes a transcription factor while MYH11 encodes the smooth muscle form of myosin heavy chain (SMMHC). To identify target genes of CBFb-SMMHC that are important in leukemia, we are taking two separate approaches: 1. serial analysis of gene expression (SAGE) of human leukemia samples and 2. cDNA microarray analysis of mouse embryonic stem (ES) cells with CBFB-MYH11 expression. Using SAGE, we performed genome-wide analyses of gene expression in 5 AML cases with inv(16). One SAGE library was made from each patient sample and over 50,000 tags were sequenced from each library. The results were analyzed relative to SAGE data from a normal bone marrow library. For the cDNA microarray analysis, RNA from mouse ES cells with CBFB-MYH11 turned on or off was isolated and used to generate cDNA probes to hybridize to a mouse 31K array. Potential target genes are now confirmed by quantitative PCR and promoter regions are being analyzed. These two complementary approaches will hopefully facilitate the identification of true targets of CBFB-MYH11 during leukemogenesis. Using a yeast two-hybrid screening approach we identified the c-Myc promoter binding protein (MBP-1) as a binding target of CBFB. MBP-1 binds to the promoter of the c-Myc gene and negatively regulate the expression of c-Myc, which is dysregulated in most cancer cells including leukemia, resulting in unbalanced control of cell proliferation, differentiation, or apoptosis. Subsequent studies suggest that MBP-1 may be a functional bridge between c-Myc and CBFB-MYH11 in human leukemia. We have generated mice expressing CBFB-MYH11 with various deletions of MYH11 by gene targeting in mouse ES cells. These mice are analyzed for defects in blood formation and in leukemia development. This study will tell us the functional domains of MYH11 required for leukemia development.

16染色体反转（16）是人类急性髓样白血病（AML）中最常见的染色体异常之一。核心结合因子B（CBFB）基因与肌球蛋白重链11（MYH11）基因之间的融合基因是由这种反转产生的。 CBFB编码转录因子，而MYH11编码肌球蛋白重链（SMMHC）的平滑肌形式。为了鉴定在白血病中很重要的CBFB-SMMHC的靶基因，我们采用了两种单独的方法：1。人白血病样品的基因表达（SAGE）的序列分析和2个。用CBFB-MYH11表达的小鼠胚胎干细胞（ES）细胞的cDNA微阵列分析。使用SAGE，我们在5个AML病例中对基因表达进行了全基因组的分析（16）。从每个患者样本中制作了一个鼠尾草库，并从每个库中对超过50,000个标签进行了测序。相对于来自正常骨髓文库的鼠尾草数据，分析了结果。对于cDNA微阵列分析，分离了带有CBFB-MYH11的小鼠ES细胞的RNA打开或关闭，并用于生成cDNA探针以杂交与小鼠31K阵列杂交。现在通过定量PCR确认潜在的靶基因，并且正在分析启动子区域。这两种互补方法有望促进白血病发生过程中CBFB-MYH11的真实靶标的鉴定。 使用酵母双杂交筛选方法，我们将C-MYC启动子结合蛋白（MBP-1）鉴定为CBFB的结合靶标。 MBP-1与C-MYC基因的启动子结合，并对C-MYC的表达进行负调节，C-MYC的表达在包括白血病在内的大多数癌细胞中失调，导致对细胞增殖，分化或凋亡的控制不平衡。随后的研究表明，MBP-1可能是人类白血病中C-MYC和CBFB-MYH11之间的功能桥梁。 我们已经产生了用小鼠ES细胞中的基因靶向基因靶向MyH11的CBFB-MYH11的小鼠。分析这些小鼠的血液形成和白血病发育缺陷。这项研究将告诉我们白血病开发所需的MYH11功能域。