MPN-inducing mutations as biomarkers of synthetic lethality

MPN 诱导突变作为合成致死率的生物标志物

• 批准号: 10174883
• 负责人: TOMASZ SKORSKI
• 金额: $ 42.77万
• 依托单位: TEMPLE UNIV OF THE COMMONWEALTH
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-01 至 2025-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10174883
• 关键词: Acute Myelocytic Leukemia; Affect; BRCA deficient; BRCA mutations; Back; Base Excision Repairs; Biological Markers; Blood; Cell Survival; Cells; Chronic Phase; DNA; DNA Double Strand Break; DNA Repair; DNA Repair Disorder; DNA Repair Gene; DNA Single Strand Break; DNA replication fork; DNA-PKcs; DNA-dependent protein kinase; Defect; Disease; Disease remission; Double Strand Break Repair; Down-Regulation; Drug Targeting; EZH2 gene; Epigenetic Process; FDA approved; Foundations; Gene Mutation; Genes; Genetic; Hemorrhagic Thrombocythemia; Immunodeficient Mouse; Induced Mutation; JAK1 gene; JAK2 gene; Knock-in; Knock-out; LIG4 gene; MPL gene; Malignant - descriptor; Malignant Neoplasms; Mediating; Modality; Modeling; Mus; Mutate; Mutation; Mutation Analysis; Myeloproliferative disease; Myelosuppressive Therapy; New Agents; Nonhomologous DNA End Joining; Normal Cell; Normal tissue morphology; Pathway interactions; Patients; Pharmaceutical Preparations; Play; Polycythemia Vera; Primary Myelofibrosis; Prognostic Marker; Proliferating; Published Comment; Reactive Oxygen Species; Reporting; Research; Role; Testing; Therapeutic; Therapeutic Effect; Time; Toxic effect; Update; Xenograft procedure; base; brca gene; calreticulin; cancer cell; cancer therapy; driver mutation; homologous recombination; humanized mouse; hydroxyurea; improved; in vivo evaluation; individual patient; inhibitor/antagonist; kinase inhibitor; leukemia/lymphoma; mouse model; novel therapeutic intervention; novel therapeutics; potential biomarker; pre-clinical; prevent; recombinational repair; repaired; response; stem cells; therapy outcome

Myeloproliferative neoplasms (MPNs) such as polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF) often carry JAK2(V617F), MPL(W515L) and mutations in calreticulin (CALRmut). These aberrations may be accompanied by mutations in TET2, ASXL1, DNMT3A, EZH2, and other genes further complicating utilization of MPNs genetic/epigenetic signatures as potential biomarkers for therapeutic decisions. Current treatment options for MPNs include myelosuppressive therapy in the form of hydroxyurea and JAK1/2 inhibitor QAK1/2i) ruxolitinib. MPNs can have prolonged chronic phases, but may eventually accelerate and transform into a secondary acute myeloid leukemia that is ultimately fatal. Therefore, it is imperative to generate new therapies that alone or in combination with already approved drugs could potentially extend the complete remission time and/or be used in patients which progressed to the malignant stage. Since all 3 "main" mutations [JAK2 (V617F), CALR(del52), and MPL(W515L)] were found in MPN stem cells (MPNSCs) these cells must be eliminated in order to improve therapeutic outcome. Unfortunately, the potential therapeutic approaches against MPNSCs are limited. MPN cells, including MPNSCs accumulate potentially lethal DNA double-strand breaks (DSBs), which are repaired by two major mechanisms, BRCA-mediated homologous recombination (HR) and DNA-PK -mediated non-homologous end-joining (D-NHEJ). HR and D-NHEJ repair DSBs in proliferating cells and D-NHEJ plays a major role in quiescent cells. PARP1 -dependent back-up NHEJ (B-NHEJ) serves as back-up in both proliferating and quiescent cells. Cancer-specific defects in DSB repair create the opportunity to employ synthetic lethality, e.g. elimination of BRCA1/2-mutated cancer cells by PARP1 inhibitor (PARP1i). However, BRCA1/2 mutations are rare in MPNs. We hypothesize that MPN-inducing mutations are prognostic biomarkers of therapeutic synthetic lethality triggered by DNA repair inhibitors. We will determine if specific MPN-inducing mutation(s) (biomarkers) predispose quiescent and/or proliferating MPN stem and progenitor cells from individual patients to PARP1i-induced synthetic lethality combined with the inhibitors of HR and D-NHEJ (Aim #1) or with JAK2i (Aim #2). We will also employ murine knockin/knockout models of MPNs and primary MPN xenografts in humanized immunodeficient mice to determine if DNA repair inhibitors and/or JAK2i exert anti-MPN synthetic lethal effect in pre-clinical settings (Aim #3).

骨髓增生性肿瘤 (MPN)，例如真性红细胞增多症 (PV)、原发性血小板增多症 (ET) 和原发性骨髓纤维化 (PMF) 通常携带 JAK2(V617F)、MPL(W515L) 和 钙网蛋白（CALRmut）。这些畸变可能伴随着 TET2、ASXL1、 DNMT3A、EZH2 和其他基因使 MPN 遗传/表观遗传的利用进一步复杂化 签名作为治疗决策的潜在生物标志物。 目前 MPN 的治疗选择包括骨髓抑制治疗 羟基脲和 JAK1/2 抑制剂 QAK1/2i) 鲁索替尼。 MPN 可能有较长的慢性期， 但最终可能会加速并转变为继发性急性髓系白血病 最终是致命的。因此，迫切需要开发单独或联合使用的新疗法 与已批准的药物一起使用可能会延长完全缓解时间和/或 进展到恶性阶段的患者。由于所有 3 个“主要”突变 [JAK2 (V617F)， 在 MPN 干细胞 (MPNSC) 中发现了 CALR(del52) 和 MPL(W515L)]，这些细胞必须是 消除以改善治疗效果。不幸的是，潜在的治疗 针对 MPNSC 的方法有限。 MPN 细胞，包括 MPNSC，会积累潜在致命的 DNA 双链断裂 (DSB)， 通过两种主要机制修复，BRCA 介导的同源重组 (HR) 和 DNA-PK 介导的非同源末端连接 (D-NHEJ)。 HR 和 D-NHEJ 修复 DSB 增殖细胞和 D-NHEJ 在静止细胞中起主要作用。 PARP1依赖的备份NHEJ (B-NHEJ) 作为增殖细胞和静止细胞的后备。 DSB 修复中的癌症特异性缺陷为利用合成致死性创造了机会，例如 PARP1 抑制剂 (PARP1i) 消除 BRCA1/2 突变的癌细胞。然而，BRCA1/2 MPN 中突变很少见。我们假设 MPN 诱导突变具有预后意义 DNA 修复抑制剂引发的治疗性合成致死的生物标志物。 我们将确定特定的 MPN 诱导突变（生物标志物）是否容易导致静止期 和/或 PARP1i 诱导的个体患者 MPN 干细胞和祖细胞的增殖 与 HR 和 D-NHEJ 抑制剂（目标 #1）或 JAK2i（目标 #2）结合使用时产生合成致死率。 我们还将采用小鼠 MPN 敲入/敲除模型和原代 MPN 异种移植物 人源化免疫缺陷小鼠以确定 DNA 修复抑制剂和/或 JAK2i 是否发挥抗 MPN 临床前环境中的合成致死效应（目标#3）。