THE ROLE OF STATS IN TRANSFORMATION BY BCR/ABL

统计数据在 BCR/ABL 转型中的作用

• 批准号: 6537502
• 负责人: ROBERT L ILARIA
• 金额: $ 27.3万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-01 至 2004-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6537502
• 关键词: Retroviridae; apoptosis; biological signal transduction; bone marrow; carcinogenesis; cell differentiation; cell proliferation; chimeric proteins; chromosome translocation; gene expression; gene targeting; genetic transcription; genetically modified animals; hematopoietic growth factor; interleukin 3; laboratory mouse; leukemia; neoplastic transformation; oncoproteins; protein structure function; provirus; tissue /cell culture; transcription factor; transfection /expression vector; virus protein

The chimeric fusion protein Bcr/Abl has been implicated in a variety of human hematologic malignancies, including the vast majority of cases of chronic myelogenous leukemia (CML), 20-30 percent of acute lymphocytic leukemia (ALL) in adults, and rare cases of acute myelogenous leukemia (AML). Recently it has been demonstrated that P210BCR/ABL activates members of the signal transducers and activators of transcription (STAT ) family members, implicated in cytokine and growth factor signaling pathways. STAT5 is the major STAT activated by p210BCR/ABL and STAT5 activation is a common feature in Philadelphia chromosome positive (Ph+) cell lines. P190BCR/ABL and v-AB1, which share the propensity for lymphoid transformation in vivo, differ from P210 in that they also STAT6, implicated in IL-4-dependent lymphoid signaling. This proposed work has two broad purposes (1) to determine the role of STAT5 activation in P210 transformation. This will be investigated by introducing dominant negative forms of STAT5 into hematopoietic factor- dependent cell lines and determining whether they interfere with the ability of P210 to render these cells cytokine independent. Also, murine bone marrow cells, co-expressing both P210 and dominant negative STAT5, will be used to reconstitute lethally- irradiated mice to determine whether dominant negative STAT5 impairs P210-induced leukemia in vivo. In a complementary experiment, wild-type mice will be reconstituted with P210- infected bone marrow from STAT5A and STAT5A/5B knockout mice to determine whether recipient animals show resistance to P210- induced leukemia. P210-infected STAT5 knockout bone marrow will also analyzed for defects in hematopoietic transformation in vitro by a myeloid colony assay (2) to determine the role of STAT6 activation in transformation by P190 and v-Abl This will be accomplished by introducing either P 190 or v-Abl into bone marrow cells from mice with homozygous deficiency of STAT6 by retroviral gene transfer, and assessing transformation in Whitlock-Witte and soft agar colony assays in vitro, and for the ability of these cells to induce leukemia in vivo when used to reconstitute lethally-irradiated STAT6 wild-type animals. Insight into the role of STAT activation by Bcr/Abl and v-Abl may lead to novel targeted therapies for patients afflicted with Philadelphia chromosome positive leukemias.

嵌合融合蛋白Bcr/Abl与多种人类恶性血液病有关，包括绝大多数慢性髓细胞性白血病（CML）病例、20- 30%的成人急性淋巴细胞性白血病（ALL）病例和罕见的急性髓细胞性白血病（AML）病例。 最近的研究表明，P210 BCR/ABL激活信号转导和转录激活因子（STAT）家族成员，参与细胞因子和生长因子信号通路。 STAT 5是由p210 BCR/ABL激活的主要STAT，并且STAT 5激活是费城染色体阳性（Ph+）细胞系的共同特征。 P190 BCR/ABL和v-AB 1在体内具有淋巴转化的倾向，与P210的不同之处在于它们也是参与IL-4依赖性淋巴信号传导的STAT 6。 这项工作有两个主要目的：（1）确定STAT 5激活在P210转化中的作用。 这将通过将STAT 5的显性负性形式引入造血因子依赖性细胞系并确定它们是否干扰P210使这些细胞不依赖于细胞因子的能力来研究。此外，共表达P210和显性阴性STAT 5的鼠骨髓细胞将用于重建致死性照射的小鼠，以确定显性阴性STAT 5是否在体内损害P210诱导的白血病。 在补充实验中，野生型小鼠将用来自STAT 5A和STAT 5A/5 B敲除小鼠的P210感染的骨髓重建，以确定受体动物是否显示对P210诱导的白血病的抗性。 P210感染的STAT 5敲除骨髓还将通过骨髓集落测定（2）分析体外造血转化中的缺陷，以确定STAT 6活化在P190和v-Abl转化中的作用。这将通过逆转录病毒基因转移将P190或v-Abl引入来自具有纯合性STAT 6缺陷的小鼠的骨髓细胞中来实现，并在体外Whitlock-Witte和软琼脂集落测定中评估转化，以及当用于重建致死照射的STAT 6野生型动物时，这些细胞在体内诱导白血病的能力。深入了解Bcr/Abl和v-Abl激活STAT的作用可能会为费城染色体阳性白血病患者带来新的靶向治疗。