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）：有一个明确的未满足的需求，开发新的，有针对性的和更安全的治疗急性髓性白血病（AML）。大约30%的AML携带核磷蛋白1（NPM 1）的杂合突变，导致突变型NPM 1（mtNPM 1）的胞质错位。野生型NPM 1（wtNPM 1）是一种核仁磷蛋白，作为蛋白质和核酸的分子伴侣发挥作用（4）。NPM 1的N端保守寡聚化结构域对于其多种功能至关重要。在AML中，胞质错位的mtNPM 1的存在减弱了核仁wtNPM 1的水平。作为AML的创始突变，mtNPM 1是髓系恶性肿瘤的单倍不足肿瘤抑制因子，似乎也赋予AML表型功能的获得。虽然它的存在与AML中相对较好的预后相关，但mtNPM 1通常与突变型FLT-3-ITD（内部串联重复）共表达，这代表了AML的侵袭性和相对难治性亚型。最近，我们报道了NPM 1的水平和/或功能的敲低诱导AML细胞的生长停滞，分化和凋亡的mtNPM 1，以及敏感的AML细胞对全反式维甲酸（ATRA）诱导的分化。因此，在靶向敲低NPM 1的水平和/或功能沿着分化诱导剂或FLT 3-TKI后，充分评价抗AML疗效及其机制有很强的理论基础和需求。基于此，本提案的目的是填补我们关于NPM 1敲低诱导分化和凋亡以及增加具有mtNPM 1的AML细胞对分化诱导治疗和FLT 3-TKI的敏感性的机制的知识中的差距。在小鼠模型中进行的体外和体内研究将为进一步临床开发基于NPM 1拮抗剂的AML治疗的新型组合提供支持性临床前数据。这些研究将检验统一的假设，即NPM 1水平/功能的敲低克服了分化停滞，并使表达mtNPM 1的AML细胞对分化诱导剂敏感，以及使共表达FLT 3-ITD和mtNPM 1的AML细胞对FLT 3-TKI敏感。该提案的具体目的是：目的1：确定NPM 1（mtNPM 1与wtNPM 1 + mtNPM 1）水平或功能敲低对表达mtNPM 1的培养和患者来源的原代AML细胞的细胞生长、分化和存活的体外和体内影响。目标2：为了确定敲低NPM 1水平或功能对分化诱导剂的体外和体内活性的致敏作用，全反式视黄酸（ATRA）或组蛋白脱乙酰酶（HDAC）抑制剂，针对培养的和原代AML细胞。目标3：在共表达mtNPM 1和FLT 3-ITD的培养和原代AML细胞中测定NPM 1和FLT 3-ITD联合靶向的体外和体内抗AML活性。总的来说，这些目标将建立NPM 1作为一个“可药物化”的目标，并为进行高通量筛选和开发靶向NPM 1的新型化合物以治疗表达mtNPM 1的AML铺平道路。