Pathologic Signaling Pathways in AML Cells

摘要：急性髓系白血病(AML)是一种严重影响美联航的血癌。 各州退伍军人和其他个人。多项研究表明，积极的 信号通路是白血病细胞转化的必要步骤。然而， 在Flt3野生型AML中激活信号的机制(S)描述得很少。我们 假设PI3激酶通路的结构性激活导致一种 称为哺乳动物雷帕霉素靶标2(MTORC2)的复合体，它调节不同的 AML细胞中平衡细胞生长和存活的途径。在这项提案中，我们将 定义这些信号通路，并确定mTORC2是单独抑制还是在 与其他药物联合使用将提高AML临床前模型的存活率 为这种具有挑战性的疾病带来了新的治疗方法。 1.目标(S)：研究建议的总体目标是明确 AML细胞中激活的细胞信号转导机制，决定生化 急性髓系白血病细胞中受mTORC2调控的信号转导通路及其是否被抑制 在临床前模型中可以增加AML患者的存活率。 2.研究设计：提出三个具体目标。明确目标1)确认 4EBP1在人类AML样本中是mTORC2而不是mTORC1的靶标，并定义 MTORC2是否调节细胞的存活或生长。具体目标2)确定是否 MTORC2调节AML细胞中FOXO-3的磷酸化，从而调节细胞存活。 特定目标3)确定mTORC1/mTORC2组合抑制在 联合化疗或Bcl2抑制AML细胞生长 临床模型。 3.方法：特异性靶点1将主要使用人急性髓系白血病细胞和原代 培养中的人急性髓系白血病细胞。具体目标2将使用类似的方法，但也会评估 用染色质免疫沉淀法将FOXO与DNA结合。《特定目标3》将聚焦于 本实验室建立的AML异种移植模型的研究进展。 4.研究结果：我们预计会确认mTORC2实际上是一个主调控因子 急性髓系白血病细胞中的信号传导。特别是，我们预计mTORC2调节4EBP1到 调节蛋白质翻译。我们还预计mTORC2调节FOXO蛋白以 调节c-Myc的表达。最后，我们预计mTORC2抑制将起作用 单独或与其他疗法联合使用，以抑制AML细胞在体内的存活。 5.临床关系：这些研究将使用来自患者的原始材料 并将用于开发一种治疗该疾病的新方法。

Abstract: Acute myeloid leukemia (AML) is a serious blood cancer that affects United States Veterans and other individuals. Multiple studies have demonstrated that active signaling pathways are a necessary step to leukemic cell transformation. However, the mechanism(s) of activated signaling in FLT3 wild type AML are poorly described. We hypothesize that constitutive activation of the PI3 kinase pathway leads to activation of a complex called mammalian target of rapamycin 2 (mTORC2) which regulates diverse pathways to balance cell growth and survival in AML cells. In this proposal, we will define these signaling pathways and determine if inhibition of mTORC2 alone or in combination with other drugs will enhance survival in pre-clinical models of AML leading to new therapies for this challenging disease. 1. Objective(s): The overall objective of the research proposal is to define the mechanisms of activated cell signaling in AML cells, determine the biochemical pathways regulated by mTORC2 in AML cells and determine if inhibition of mTORC2 in pre-clinical models can increase survival of individuals with AML. 2. Research Design: We propose three Specific Aims. Specific Aim 1) Confirm that 4EBP1 is a target of MTORC2 and not MTORC1 in human AML samples and define whether MTORC2 regulates cell survival or cell growth. Specific Aim 2) Determine if mTORC2 Regulates FOXO 3 phosphorylation in AML cells to Regulate Cell Survival. Specific Aim 3) Determine if combinatorial MTORC1/MTORC2 inhibition in combination with chemotherapy or Bcl2 inhibition suppresses AML cell growth in pre- clinical models. 3. Methodology: Specific Aim 1 will primary use human AML cells and primary human AML cells in culture. Specific Aim 2 will use similar methods but also assess FOXO binding to DNA using chromatin immunoprecipitation. Specific Aim 3 will focus on studies in a xenotransplantation model of AML developed by our laboratory. 4. Findings: We anticipate confirming that mTORC2 is actually a master regulator of signaling in AML cells. In particular, we anticipate that mTORC2 regulates 4EBP1 to regulate protein translation. We also anticipate that mTORC2 regulates FOXO proteins to regulate c-Myc expression. Finally, we anticipate that mTORC2 inhibition will work alone or in combination with other therapies to inhibit AML cell survival in vivo. 5. Clinical Relationships: These studies will use primary material from patients with AML and will be used to develop a new approach to therapy of the disease.