Molecular Pathology of t-AML

治疗相关性急性髓细胞白血病（t-AML）的发生率随着治愈率的提高而持续增加。 对多种癌症的治疗效果都有所改善。不幸的是，t-AML是一种高度侵袭性的疾病， 可治愈，使用当前疗法的中位总生存率低于10%。详细细胞遗传学 t-AML的分子研究，部分由该项目资助，提供了重要的 深入了解这种疾病的潜在分子发病机制，包括长臂的丧失， 在大多数患者中，5号染色体[-5/del（5 q）]和/或7号染色体[-7/del（7 q）]完全丢失， AML 1/RUNX 1、FLT 3、MLL、NRAS、cKIT和p53突变。然而， 导致t-AML发展的协同病变仍有待确定。我们相信 在分子水平上定义有助于t- AML不仅可以提高我们准确诊断这种疾病的能力，而且还有助于定义 分子的“阿喀琉斯之踵”，可以针对其开发靶向治疗。的长期目标 该项目旨在确定t-AML中发生的遗传改变的补充。这一目标将是 通过两个具体目标来追求：（1）识别体细胞获得的遗传拷贝数改变， AML，并阐明其对细胞转化的机制贡献;和（2）鉴定 在选定的癌症相关基因子集中的体细胞获得的序列突变。后者将 包括已知的癌基因和被鉴定为具有拷贝数改变或改变的基因 表达谱。这些特定的目标将使用高分辨率全基因组组合来实现。 对获得的超过200个t-AML样本的队列进行拷贝数分析和靶向重测序 通过患者访问、数据管理、统计分析和组织培养核心（核心A）。 拷贝数分析将使用Affyscore全基因组人类SNP阵列6.0进行，其 分辨率<5 kb。重要的是，匹配的生殖系样本要么可用，要么将 通过扩增每个患者的BM基质成纤维细胞或反应性T细胞产生，使我们能够 明确确定所鉴定的拷贝数变化是否是体细胞获得的。的基因突变 被鉴定为复发性拷贝数改变的靶点的人将使用FISH或基因组学方法进行确认。 定量PCR，并将测序以鉴定任何点突变的存在。所识别的 然后通过评估基因对细胞转化的贡献， 对正常造血干细胞生长和分化的影响，以及对它们与 已知的致癌病变诱发白血病。

The frequency of therapy-related acute myeloid leukemia (t-AML) continues to increase as the cure rates for a wide-variety of cancers improves. Unfortunately, t-AML is a highly aggressive disease and is rarely curable, with median overall survival rates using current therapies of less than 10%. Detailed cytogenetic and molecular studies of t-AML, in part supported by this program project grant, have provided important insights into the underlying molecular pathogenesis of this disease including the loss of the long arm or total loss of chromosomes 5 [-5/del(5q)] and/or 7 [-7/del(7q)] in the majority of patients, and the frequent mutation of AML1/RUNX1, FLT3, MLL, NRAS, cKIT, and p53. However, the full complement of cooperating lesions responsible for the development of t-AML remains to be defined. It is our belief that defining at a molecular level the total complement of alterations that contribute to the development of t- AML will not only enhance our ability to accurately diagnosis this disease, but should also help to define the molecular "Achilles heels" against which targeted therapy can be developed. The long-term goal of this project is to identify the complement of genetic alterations that occur in t-AML. This objective will be pursued through two specific aims: (1) To identify somatically acquired genetic copy number alterations t- AML and to elucidate their mechanistic contribution to cellular transformation; and (2) To identify somatically acquired sequence mutations in a selected subset of cancer related genes. The latter will include known cancer genes and genes identified as either having copy number alterations or altered expression profiles. These specific aims will be pursued using a combination of high resolution genomewide copy number analysis and targeted resequencing on a cohort of over 200 t-AML samples obtained through the Patient Access, Data Management, Statistical Analysis, and Tissue Culture Core (Core A). Copy number analysis will be performed using Affymetrix Genome-Wide human SNP Array 6.0, which provides a resolution of <5 kb. Importantly, matched germ line samples are either available or will be generated by expansion of BM stromal fibroblasts or reactive T-cells for every patient, allowing us to definitively determine if an identified copy number change is somatically acquired. Gene mutations that are identified as the targets of recurrent copy number alterations will be confirmed using FISH or genomic quantitative PCR, and will be sequenced to identify the presence of any point mutations. The identified genes will then be directly assessed for their contribution to cellular transformation by evaluating their effect on normal hematopoietic stem cell growth and differentiation, and on their ability to cooperate with known oncogenic lesions to induce leukemia.