MOLECULAR TARGETS OF TRANSLOCATION T(4;14) IN MULTIPLE MYELOMA PATHOGENESIS

多发性骨髓瘤发病机制中 T(4;14) 易位的分子靶点

基本信息

批准号：
8630472
负责人：
MICHAEL H TOMASSON
金额：
$ 32.92万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-01-01 至 2018-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8630472
关键词：
13q 13q14 4p16.3 Affect American Antibodies B-Cell Development B-Lymphocytes Biological Assay Bone Marrow Boxing Cancer Biology Cancer Control Cancer Etiology Cell Line Cells Cessation of life Chromosomal translocation Chromosomes, Human, Pair 13 DNA Sequence Data Development Diagnosis Disease Etiology Event Functional RNA Gene Targeting Genes Genetic Hematologic Neoplasms Human Immunodeficient Mouse Knockout Mice Length Malignant - descriptor Malignant Neoplasms Maps Measures Mediating Messenger RNA MicroRNAs Modeling Molecular Target Mouse Cell Line Mouse Strains Multiple Myeloma Mus Mutation Oncogenes Oncogenic Orphan Oxidative Stress Pathogenesis Patients Phenotype Plasma Protein Binding Domain RB1 gene RNA Binding RNA Sequences Reactive Oxygen Species Relative (related person)Resistance Retinoblastoma Role Sampling Series Small Nucleolar RNA Small RNA Spleen Structure Structure of germinal center of lymph node System Testing Tissues Transformed Cell Line Transplantation United States WHSC1 gene cancer type cell growth chemotherapy chromosome 13 loss histone methyltransferase in vivo insight knock-down mutant novel novel therapeutic intervention outcome forecast protein expression public health relevance research study tumor

项目摘要

Multiple Myeloma (MM) is the second most common hematologic malignancy in the United States, diagnosed in approximately 14,500 Americans each year, and is responsible for 2% of all cancer deaths (SEER.cancer.gov). MM is an incurable malignancy of antibody-secreting plasma B-cells whose etiology is poorly understood. Chromosomal translocation t(4;14)(p16.3;q32.33) is associated with shorter overall survival and is found in 15% of MM patients. The candidate oncogene WHSC1 (MMSET) at 4p16.3 encodes a histone methyltransferase over-expressed as a result of the t(4;14) in MM cells. Surprisingly, over-expression of WHSC1 cDNA's failed to transform cell lines or to induce any phenotype when expressed in mice. We identified ACA11, an orphan box H/ACA small nucleolar RNA (snoRNA) encoded hosted within WHSC1 at 4p16.3, to be up-regulated in cell lines and MM patient samples harboring t(4;14). ACA11 modulates oxidative stress, contributes to MM cell growth and confers resistance to chemotherapy. ACA11 is a novel oncogenic non-coding RNA and is also expressed in other cancer types. Mutations that cooperate with t(4;14) in myeloma initiation are unknown, but chromosome 13 deletions (Del(13)) are highly correlated with the t(4;14) in MM. Del(13) is found in 85-94% of patients with t(4;14) and associated with poor prognosis. We mapped a minimally deleted region in MM patient samples to the retinoblastoma (RB1) gene at 13q14. Our model is that ACA11 expression cooperates with RB1 loss to cause poor-prognosis MM. We propose to characterize the role of ACA11 in multiple myeloma. Specific Aim 1: Cooperation between ACA11 and the histone methyltransferase WHSC1. We hypothesize that ACA11 cooperates with MMSET protein expression in myeloma pathogenesis and that WHSC1 histone methyltransferase activity is required for cooperation. We will co-express wild-type WHSC1 or HMT-dead WHSC1 alone or with ACA11 in cell lines and mice. Specific Aim 2: Aim 2: How does ACA11 affect levels of ROS and sensitivity to chemotherapy? What domains and partners of ACA11 are required for these effects? Our data suggest that ACA11 modulates reactive oxygen species and resistance to chemotherapy in myeloma. We will determine which residues of ACA11 are required for this function. We hypothesize that ACA11 RNA binding residues will be dispensable for ACA11's oxidative stress function, but that ACA11's protein-binding domains will be critical. Specific Aim 3: ACA11-mediated malignant transformation in the context of Rb1 deletion. The long arm of chromosome 13 is deleted in 50% of all MM patients, and in 90% of patients with the t(4;14). We hypothesize that RB1 loss cooperates with the t(4;14) in myeloma pathogenesis. We will test the effects of ACA11 and WHSC1 expression on B-cell development, oxidative stress and transformation in the context of Rb1 deficiency. Lastly, we will [identify target genes of t(4;14) by RNA- sequencing patient samples.] A betting understanding of how the t(4;14) contributes to myelomagenesis has broad implications to cancer biology and will facilitate the development of novel therapeutic approaches to patients with poor-prognosis MM.

多发性骨髓瘤 (MM) 是美国第二常见的血液恶性肿瘤，诊断每年约有 14,500 名美国人死于癌症，占所有癌症死亡的 2% （SEER.cancer.gov）。 MM 是一种无法治愈的、分泌抗体的血浆 B 细胞恶性肿瘤，其病因是不太了解。染色体易位 t(4;14)(p16.3;q32.33) 与较短的总生存期相关 15% 的 MM 患者中存在这种情况。 4p16.3 处的候选癌基因 WHSC1 (MMSET) 编码组蛋白 MM 细胞中 t(4;14) 导致甲基转移酶过度表达。令人惊讶的是，过度表达 WHSC1 cDNA 在小鼠中表达时未能转化细胞系或诱导任何表型。我们鉴定出 ACA11，一种孤儿盒 H/ACA 小核仁 RNA (snoRNA)，编码于 WHSC1 内 4p16.3，在含有 t(4;14) 的细胞系和 MM 患者样本中上调。 ACA11 调节氧化压力，有助于 MM 细胞生长并赋予对化疗的抵抗力。 ACA11是一种新型致癌物非编码 RNA，也在其他癌症类型中表达。在骨髓瘤发生过程中与 t(4;14) 配合的突变尚不清楚，但 13 号染色体缺失 (Del(13)) 与 MM 中的 t(4;14) 高度相关。 Del(13) 存在于 85-94% 的 t(4;14) 和与预后不良有关。我们将 MM 患者样本中的最小删除区域映射到视网膜母细胞瘤 (RB1) 基因位于 13q14。我们的模型是ACA11表达与RB1损失配合导致预后不良的MM。我们建议描述 ACA11 在多发性骨髓瘤中的作用。具体目标1： ACA11 与组蛋白甲基转移酶 WHSC1 之间的合作。我们假设 ACA11 WHSC1 组蛋白与 MMSET 蛋白表达在骨髓瘤发病机制中协同作用合作需要甲基转移酶活性。我们将共表达野生型 WHSC1 或 HMT-dead 在细胞系和小鼠中单独使用 WHSC1 或与 ACA11 一起使用。具体目标 2：目标 2：ACA11 如何影响水平 ROS 和对化疗的敏感性？这些需要 ACA11 的哪些域和合作伙伴影响？我们的数据表明，ACA11 调节活性氧和化疗耐药性骨髓瘤。我们将确定该功能需要 ACA11 的哪些残基。我们假设 ACA11 RNA 结合残基对于 ACA11 的氧化应激功能来说是可有可无的，但 ACA11 的蛋白质结合域将至关重要。具体目标 3：ACA11 介导的恶性转化 Rb1 缺失的背景。 50% 的 MM 患者的 13 号染色体长臂被删除，90% 的 MM 患者的 13 号染色体长臂被删除。 t(4;14) 患者。我们假设 RB1 缺失与 t(4;14) 在骨髓瘤发病机制中协同作用。我们将测试 ACA11 和 WHSC1 表达对 B 细胞发育、氧化应激和 Rb1 缺乏情况下的转化。最后，我们将[通过RNA-鉴定t(4;14)的靶基因对患者样本进行测序。] 对 t(4;14) 如何促进骨髓瘤发生的押注理解对癌症生物学产生广泛影响，并将促进新型治疗方法的开发预后不良的MM患者。