The Role of SKIDA1 in Acute Myeloid Leukemia Initiation and Maintenance

SKIDA1 在急性髓系白血病发生和维持中的作用

基本信息

批准号：
10606263
负责人：
Jonny Mendoza-Castrejon
金额：
$ 3.36万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-08-01 至 2026-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10606263
关键词：
Acute Myelocytic Leukemia Adult Age Alleles Binding Biological Assay Blood Cells Cell Line Cells ChIP-seq Childhood Childhood Acute Myeloid Leukemia Childhood Leukemia Chimeric Proteins Chromatin Chromosomal translocation Co-Immunoprecipitations Collecting Cell Data Dependence Development Doxycycline Embryo Enhancers Frequencies Gene Expression Genes Genetic Enhancer Element Genetic Transcription Genetic study Genome Goals Hematopoiesis Hematopoietic System Hematopoietic stem cells Human Infant Infant Leukemia Knockout Mice Life Link LoxP-flanked allele MLL gene MLL-AF9 Maintenance Maps Mixed-Lineage Leukemia Monitor Mus Mutation Neonatal Neonatal Leukemia Pattern Preleukemia Retroviridae Role Testing Transplantation Work acute myeloid leukemia cell adult leukemia age related cellular transduction conditional knockout driver mutation experimental study innovation leukemia leukemogenesis loss of function mouse genetics mouse model neonate novel novel therapeutics postnatal progenitor programs promoter response self-renewal single-cell RNA sequencing targeted treatment transcriptome transcriptome sequencing

项目摘要

ABSTRACT Chromosomal translocations involving the MLL1 gene often drive infant acute myeloid leukemia (AML). MLL fusion proteins (e.g., MLL-ENL, MLL-AF9, MLL-AF10) activate self-renewal programs in hematopoietic stem and progenitor cells, ultimately leading to transformation. The high frequency of MLL1 rearrangements in infant leukemias suggests that neonatal progenitors are uniquely poised to transform in response to these mutations. Indeed, we have recently shown that MLL-ENL initiates AML more efficiently in neonatal progenitors than in adult progenitors. This raises the question of whether MLL-ENL induces key effectors of transformation more efficiently in neonatal progenitors than in adult progenitors. We identified Ski/Dach Domain Containing 1 (Skida1) as a gene that is highly induced by MLL-ENL in neonatal, but not adult hematopoietic progenitors. SKIDA1 is also highly expressed in human pediatric MLL1 rearranged AML. Expression is largely restricted to leukemias with MLL1 rearrangements. To test whether Skida1 promotes leukemogenesis, we generated a germline loss-of-function mouse allele. Skida1 deletion by itself had negligible effects on normal hematopoiesis, consistent with the lack of expression in normal hematopoietic progenitors. Furthermore, Skida1 deletion did not affect normal HSC function. However, when we induced MLL-ENL expression in Skida1-/- neonates, we observed near complete loss of HSCs and a severe reduction in lineage committed hematopoietic progenitor cells (HPCs). Thus, Skida1-dependence emerges as a consequence of MLL-ENL expression. Next, we generated a conditional loss-of-function mouse allele. Skida1 conditional deletion in the hematopoietic system did not perturb normal hematopoiesis at any age. We are currently crossing the conditional Skida1 mouse to our MLL-ENL mouse model to test whether Skida1 promotes leukemogenesis in the context of MLL-ENL-expressing progenitors. Thus, I hypothesize that Skida1 sustains pre-leukemic HSCs and HPCs and promotes AML during neonatal stages of life. Aim 1 will use a Skida1 conditional knockout mouse to interrogate how Skida1 sustains MLL-ENL-expressing HSCs and HPCs. I will also test whether Skida1 is necessary to maintain fully transformed AML cells. Aim 2 builds upon Aim 1 by adding mechanistic studies to identify Skida1-dependent changes in gene expression and cell fate. I will test whether SKIDA1 binds chromatin to regulate leukemogenesis, and I will identify SKIDA1 binding partners. The aims of this proposal will evaluate SKIDA1 as a potential link between age-specific transcriptional programs and AML initiation, as well as offer a novel therapeutic vulnerability for treating infant leukemia.

抽象的涉及 MLL1 基因的染色体易位通常会导致婴儿急性髓系白血病 (AML)。最小二乘法融合蛋白（例如 MLL-ENL、MLL-AF9、MLL-AF10）激活造血干的自我更新程序和祖细胞，最终导致转化。婴儿中 MLL1 重排频率较高白血病表明，新生儿祖细胞特别容易因这些突变而发生转变。事实上，我们最近发现，MLL-ENL 在新生儿祖细胞中比在新生儿祖细胞中更有效地启动 AML。成年祖先。这就提出了一个问题：MLL-ENL 是否更多地诱导转化的关键效应子？在新生儿祖细胞中比在成人祖细胞中更有效。我们确定了 Ski/Dach 域包含 1 (Skida1) 是一种在新生儿而非成人造血祖细胞中被 MLL-ENL 高度诱导的基因。 SKIDA1 在人类儿科 MLL1 重排 AML 中也高度表达。表达方式很大程度上局限于具有 MLL1 重排的白血病。为了测试 Skida1 是否促进白血病发生，我们生成了种系功能丧失小鼠等位基因。 Skida1 缺失本身对正常的影响可以忽略不计。造血，与正常造血祖细胞中缺乏表达一致。此外， Skida1缺失并不影响HSC的正常功能。然而，当我们诱导 MLL-ENL 表达时 Skida1-/- 新生儿，我们观察到 HSC 几乎完全丧失，并且谱系严重减少造血祖细胞（HPC）。因此，Skida1 依赖性是 MLL-ENL 的结果表达。接下来，我们生成了条件性功能丧失的小鼠等位基因。 Skida1 中的条件删除造血系统在任何年龄都不会干扰正常的造血功能。我们目前正在穿越将条件 Skida1 小鼠加入到我们的 MLL-ENL 小鼠模型中，以测试 Skida1 是否促进白血病发生表达 MLL-ENL 的祖细胞的背景。因此，我假设 Skida1 维持白血病前期 HSC 和 HPC，并促进新生儿阶段的 AML。目标 1 将使用 Skida1 条件淘汰赛小鼠询问 Skida1 如何维持表达 MLL-ENL 的 HSC 和 HPC。我也来测试一下是否 Skida1 对于维持完全转化的 AML 细胞是必需的。目标 2 在目标 1 的基础上添加了机制研究确定 Skida1 依赖性基因表达和细胞命运的变化。我会测试是否有SKIDA1 结合染色质来调节白血病发生，我将确定 SKIDA1 结合伙伴。本次活动的目的该提案将评估 SKIDA1 作为年龄特异性转录程序和 AML 之间的潜在联系启动，并为治疗婴儿白血病提供了一种新的治疗方法。