Clonogenic Characterization of Myeloma Progenitor Cells

描述（由申请人提供）：多发性骨髓瘤（MM）是克隆性B细胞恶性肿瘤的原型。 造血干细胞（HSC）移植和/或新的化疗组合改善了长期无病生存。 然而，基础疾病的复发仍然是治疗失败的主要原因，MM基本上是一种不治之症。 因此，非常需要旨在提高治疗效果的策略。 该项目的中心假设是MM患者的骨髓亚群构成具有自我更新能力的祖细胞室，其负责疾病的发生、维持和进展。 这些细胞可能具有特定的特征，使它们对化疗不敏感，并且它们可能依赖于造血基质微环境存活。 我们的初步结果表明，MM患者的骨髓中含有一个克隆亚群，不表达syndecan-1（CD 138-），在克隆形成试验中分化为成熟细胞（CD 138+），对硼替佐米治疗具有相对抗性。 拟定的研究将有助于理解MM生物学，分析MM祖细胞亚群的表型和独特组成，这些亚群可能是疾病开始和/或复发的部分原因。 我们未来的目标是确定这些细胞的临床意义，并开发针对所有MM亚群的药物和/或免疫疗法。 在目标1中，我们将确定CD 138- MM细胞的分化潜力和自我更新能力。 我们建议表征CD 138- MM细胞的表型分化并建立其染色体特征。 我们计划通过患者特异性免疫球蛋白重链重排和体内克隆形成来确定其克隆性。 在目标2中，我们将通过质谱分析相关蛋白来确定自我更新途径作为CD 138- MM亚群耐药内在机制的作用。 我们将测试自我更新配体对蛋白质表达、对细胞增殖、对靶基因活化和CD 138-细胞的克隆形成生长的影响。 在目标3中，我们将确定基质细胞在赋予CD 138-细胞生存优势中的作用。 我假设微环境支持CD 138- MM细胞的克隆形成，这些细胞依赖于它的生存信号，因为基质提供了一个支持的小生境。 我推测基质成分可能为CD 138- MM亚群提供细胞保护，部分原因是细胞周期进程和/或已知MM-基质存活机制的扰动。 在追求这一目标，我们将评估基质相关的细胞因子和纤连蛋白对细胞周期的影响，并通过质谱和与药物反应的相关性对BcL-2凋亡调节因子的蛋白表达的调节。 公共卫生相关性：多发性骨髓瘤（MM）是一种无法治愈的浆细胞恶性血液病。 浆细胞在骨髓（BM）中生长并产生相同类型的异常抗体（克隆）。 迫切需要制定战略，以提高治疗效果和预防疾病复发（复发）。 癌症治疗失败的一个重要原因是导致微小残留病（MRD）的耐药性。 开发针对MRD介质的新型治疗策略对于完全根除疾病至关重要。 “癌症干细胞”概念争论肿瘤内的一些细胞通过产生癌细胞而成为癌症的根源，癌症治愈取决于根除这些细胞。 迄今为止，这些细胞在癌症生物学中的临床作用尚不清楚，对MM中这些细胞的深入了解仍有待确定。 我们的初步结果表明，MM BM包含一个不表达用于识别成熟MM细胞（浆细胞）的标志物的细胞克隆，并且对化疗不太敏感。 我们推测这些细胞可能与MM的起源和MRD有关。 我们建议确定这些细胞是否在MM生成中发挥作用，并了解这些细胞的生长调节机制。 我们计划研究自我更新途径和与BM微环境的相互作用，因为我们相信这个利基为它们的生存提供了积极的反馈。 了解这些细胞在MM中的作用并破译它们的生存工具将是至关重要的，因为如果假设被证实，根除这些细胞将在MM中产生治愈性结果。

DESCRIPTION (provided by applicant): Multiple Myeloma (MM) is the prototype of a clonal B-cell malignancy. Hematopoietic stem cell (HSC) transplantation and/or novel chemotherapy combinations have improved long-term disease free survival. However, relapse of the underlying disease remains the primary cause of treatment failure with MM being essentially an incurable disease. Therefore, strategies aiming to improve treatment efficacy are much needed. The central hypothesis of this project is that bone marrow sub-populations in MM patients constitute a progenitor compartment with self renewal capacity that is responsible for disease initiation, maintenance and progression. These cells may have a specific signature to render them insensitive to chemotherapy and they may rely on the hematopoietic stroma microenvironment for their survival. Our preliminary results show that MM patient's bone marrow contain a clonal sub-population that do not express syndecan-1 (CD138-), differentiates in clonogenic assay to a mature cell (CD138+) and is relatively resistant to bortezomib treatment. The proposed study will contribute to the understanding of MM biology analyzing the phenotypic and unique make up of a MM progenitor sub-population that may be in part responsible for disease initiation and/or relapse. Our future goal is to establish the clinical significance of these cells and to develop drugs and/or immune therapies to target all MM sub-populations. In Aim 1, we will determine the differentiation potential and self-renewal capacity of CD138- MM cells. We proposed to characterize phenotypic differentiation of CD138- MM cells and establish their chromosomal signature. We plan to define their clonality with patient-specific immunoglobulin heavy chain rearrangements and clonogenicity in vivo. In Aim 2, we will determine the role of self renewal pathways as an intrinsic mechanism of resistance of CD138- MM sub-populations by analyzing related proteins by mass spectrometry. We will test the effect of self renewal ligands on protein expression, on cell proliferation, on activation of target genes and clonogenic growth of CD138- cells. In Aim 3, we will determine the role of stroma cells in conferring a survival advantage to CD138-cells. I hypothesize that the microenvironment supports CD138- MM cells clonogenicity and these cells depend on it signals for their survival as the stroma provides a supporting niche. I postulate that stroma elements may provide cyto-protection to CD138- MM subpopulations in part due to perturbations in cell cycle progression and/or known MM-stroma survival mechanism. In pursuit of this aim we will assess stroma related cytokines and fibronectin effect on cell cycle and on modulation of protein expression of BcL-2 apoptotic regulators by mass spectrometry and correlation with drug response. PUBLIC HEALTH RELEVANCE: Multiple Myeloma (MM) is an incurable hematological malignancy of plasma cells. Plasma cells grow in the bone marrow (BM) and produce same type of abnormal antibodies (clone). Development of strategies to improve treatment efficacy and to prevent recurrence of disease (relapse) are much needed. An important cause of treatment failure in cancer is drug resistance leading to minimal residual disease (MRD). Developing novel treatment strategies to target mediators of MRD is essential for complete disease eradication. The "cancer stem cell" concept debates that some cells within the tumor are the root of cancer by producing cancer cells and cancer cure depends on the eradication of these cells. To date, the clinical role of these cells is cancer biology is unknown and deep understanding of these cells in MM remains to be determined. Our preliminary results show that MM BM contains a clone of cells that do not express markers used to identify mature MM cells (plasma cells) and are less susceptible to chemotherapy. We hypothesize that these cells maybe responsible for the origin of MM and responsible for MRD. We propose to establish whether these cells play a role in MM generation and to understand growth regulation mechanisms of these cells. We plan to study self renewal pathways and interaction with the BM micro-environment since we believe that this niche provides positive feedback for their survival. Understanding the role of these cell in MM and decipher their survival tools will be essential since eradication of these cells should produce curative results in MM if hypothesis is proven.