Novel Targeted Therapy for AML

AML 的新型靶向治疗

• 批准号: 9247879
• 负责人: KAPIL BHALLA
• 金额: $ 33.2万
• 依托单位: UNIVERSITY OF TX MD ANDERSON CAN CTR
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-05-15 至 2019-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9247879
• 关键词: Acute Myelocytic Leukemia; Apoptosis; Attenuated; Biogenesis; Cell Proliferation; Cells; Centrosome; Clinical Data; Combined Modality Therapy; DNA Repair; Development; Diagnosis; Disease remission; Dislocations; FLT3 gene; Genes; Growth; HDAC4 gene; Histone Deacetylase Inhibitor; Histones; Human; In Vitro; Knowledge; Molecular Chaperones; Mutation; Myeloproliferative disease; N-terminal; NPM1 gene; Nucleic Acids; Pathogenicity; Patients; Phenotype; Phosphoproteins; Protein Tyrosine Kinase; Proteins; Refractory; Relapse; Reporting; Ribosomes; Role; Testing; Transcriptional Regulation; Treatment-related toxicity; Tretinoin; Tumor Suppressor Proteins; Tyrosine Kinase Inhibitor; base; cell growth; chemotherapy; clinical development; founder mutation; gain of function; high throughput screening; in vivo; knock-down; mouse model; mutant; new therapeutic target; novel; nucleophosmin; outcome forecast; pre-clinical; public health relevance; targeted treatment

DESCRIPTION (provided by applicant): There is a clear unmet need to develop novel, targeted and safer therapies for acute myeloid leukemia (AML). Approximately 30% of AML carry a heterozygous mutation in the nucleophosmin 1 (NPM1), which results in the cytoplasmic dislocation of the mutant NPM1 (mtNPM1). Wild-type NPM1 (wtNPM1) is a nucleolar phosphoprotein, which functions as a molecular chaperone for proteins and nucleic acids (4). The N-terminal conserved oligomerization domain of NPM1 is critical for its multiple functions. In AML, presence of the cytoplasmic, dislocated mtNPM1 attenuates the levels of the nucleolar wtNPM1. As a founder mutation in AML, mtNPM1 is a haploinsufficient tumor suppressor of myeloid malignancies and appears to also confer a gain of function for the AML phenotype. Although its presence is associated with a relatively better prognosis in AML, mtNPM1 is often co-expressed with mutant FLT-3-ITD (internal tandem duplication), which represents an aggressive and relatively treatment-refractory sub-type of AML. Recently, we reported that knockdown of the levels and/or function of NPM1 induces growth arrest, differentiation and apoptosis of AML cells with mtNPM1, as well as sensitizes the AML cells to differentiation induced by all-trans retinoic acid (ATRA). Therefore, there is a strong rationale and need for fully evaluating the anti-AML efficacy and its mechanism following the targeted knockdown of the level and/or function of NPM1 along with a differentiation inducing agent or a FLT3-TKI. Based on this, the objectives of this proposal are to fill the gap in our knowledge about the mechanism by which knockdown of NPM1 induces differentiation and apoptosis and increases sensitivity of AML cells with mtNPM1 to differentiation-inducing therapy and FLT3-TKI. Proposed in vitro and in vivo studies in mouse models will create the supportive pre-clinical data for further clinical development of the novel combinations of NPM1 antagonist-based therapy of AML. These studies will test the unifying hypothesis that knockdown of NPM1 levels/function overcomes differentiation arrest and sensitizes AML cells that express mtNPM1 to differentiation-inducing agents, as well as sensitizes AML cells that co-express FLT3-ITD and mtNPM1 to FLT3-TKI. The specific aims of the proposal are: AIM 1: To determine the in vitro and in vivo effects of the knockdown of NPM1 (mtNPM1 versus wtNPM1 plus mtNPM1) levels or function on cell growth, differentiation and survival of cultured and patient-derived primary AML cells expressing mtNPM1. AIM 2: To determine the sensitizing effect of knockdown of NPM1 levels or function on the in vitro and in vivo activity of differentiation- inducing agents, e.g., all-trans retinoic acid (ATRA) or a histone deacetylase (HDAC) inhibitor, against cultured and primary AML cells. AIM 3: To determine the in vitro and in vivo anti-AML activity of combined targeting of NPM1 and FLT3-ITD in cultured and primary AML cells that co-express mtNPM1 and FLT3-ITD. Overall, these aims will establish NPM1 as a 'druggable' target and pave the way for performing high throughput screening and development of novel compounds that target NPM1 for the therapy of AML expressing mtNPM1.

描述（由申请人提供）：对于急性髓样白血病（AML）开发新颖，靶向和更安全的疗法有明显的未满足。 AML的大约30％在核素1（NPM1）中携带杂合突变，这导致突变NPM1（MTNPM1）的细胞质脱位。野生型NPM1（WTNPM1）是一种核酸磷蛋白，它是蛋白质和核酸的分子伴侣（4）。 NPM1的N末端保守寡聚结构域对于其多个功能至关重要。在AML中，细胞质的存在，脱位的mTNPM1减弱了核仁WTNPM1的水平。作为AML中的创始人突变，MTNPM1是髓样恶性肿瘤的单倍抑制肿瘤抑制剂，并且似乎也为AML表型提供了功能。尽管它的存在与AML的预后相对更好，但MTNPM1通常与突变体FLT-3-ITD（内部串联重复）共表达，这代表了AML的侵略性且相对差异的差异亚型。最近，我们报道了NPM1的水平和/或功能的敲低会诱导使用MTNPM1的AML细胞的分化和凋亡，并使AML细胞对由全反式视黄酸（ATRA）诱导的分化敏感。因此，在针对NPM1的水平和/或功能以及分化诱导剂或FLT3-TKI的水平和/或功能之后，有很强的理由，需要充分评估抗AML功效及其机制。基于这一点，该提案的目标是填补我们对NPM1敲低诱导分化和凋亡的机制的差距，并提高AML细胞对MTNPM1的敏感性，以诱导分化诱导疗法和FLT3-TKI。在小鼠模型中提出的体外和体内研究将创建支持性的临床前数据，以进一步临床开发基于NPM1拮抗剂的AML治疗的新型组合。这些研究将检验以下统一的假设：NPM1水平/功能的敲低克服了分化停滞，并使AML细胞表达MTNPM1对分化诱导剂的表达，以及敏感的AML细胞，这些AML细胞可表达FLT3-ITD和MTNPM1对FLT3-TKI。该提案的具体目的是：目标1：确定NPM1敲低（MTNPM1与WTNPM1加MTNPM1）水平的体外和体内影响或对细胞生长，分化和生存的功能，对培养的和患者衍生的原代AML细胞的分化和存活，表达MTNPM1。目标2：确定NPM1水平敲低的敏感性或功能对分化诱导剂的体外和体内活性的敏感性，例如全反式视网膜酸（ATRA）或组蛋白脱乙酰基酶（HDAC）抑制剂，抗培养的AML细胞。目标3：确定NPM1和FLT3-ITD联合靶向在培养的和原代AML细胞中的体外和体内抗AML活性，这些靶向MTNPM1和FLT3-ITD。总体而言，这些目标将建立NPM1作为“可药”目标，并为对靶向NPM1的新型化合物的高吞吐量筛查和开发铺平了道路，该化合物靶向AML表达MTNPM1。