NEK2 Over-expression Causes Drug Resistance in Myeloma

描述（由申请人提供）： 这项工作的长期目标是确定NEK 2在促进癌症进展中的功能作用，并利用这些知识开发新的治疗方法。多发性骨髓瘤患者生存期的变异性范围从仅几个月到>10年。我们先前已经表明，NEK 2表达在包括骨髓瘤在内的多种癌症中增加;更高水平的NEK 2表达诱导细胞快速生长和对多种化疗药物的抗性。该项目建立在我们的发现基础上，即当调节细胞周期的特定基因（NEK 2）过表达时，患者会经历骨髓瘤和其他癌症的临床侵袭性形式和快速死亡。我们已经取得了几个惊人的发现，支持NEK 2过表达破坏肿瘤细胞增殖的正常周期，导致骨髓瘤患者生存不良的假设。我们的目标是测试的假设将通过执行三个特定的目标，在体外和体内模型。目的1：探讨NEK 2在骨髓瘤发生发展中的作用。我们计划在大量不同阶段的骨髓瘤患者中评估NEK 2高表达的骨髓瘤细胞是否具有耐药性特征;我们还将在体外和体内测试NEK 2高表达或NEK 2低表达的原发性骨髓瘤细胞的生长和耐药性;我们将NEK 2引入具有低内源性NEK 2表达的正常成纤维细胞和鼠癌症衍生的骨髓瘤细胞系中，然后我们将分析这种改变对细胞转化、细胞生长和对化疗剂的反应的影响。目的2：确定NEK 2介导的癌细胞增殖和存活的信号通路。为了实现这一目标，我们将确定NEK 2介导的多发性骨髓瘤细胞生长和耐药性是否需要一些细胞生长相关的信号通路。我们将研究直接与NEK 2蛋白相互作用的关键底物。此外，将对缓解期和复发期骨髓瘤样本（基线时也有GEP）进行基因表达谱分析（GEP），以鉴定在不同骨髓瘤阶段受NEK 2调节的基因。目标3：开发基于靶向NEK 2或其信号通路的新治疗方法。通过对激酶抑制剂文库的筛选，我们鉴定了两个能够特异性抑制NEK 2激酶活性的小分子，并在体外诱导肿瘤细胞显著死亡。我们将使用这些分子作为一种工具，以探索其在体内杀死骨髓瘤细胞的功效。靶向这些信号通路的抑制剂将单独使用或与目前使用的化疗药物组合使用，以评价其体外和体内抗骨髓瘤活性。

DESCRIPTION (provided by applicant): The long-term objective of this work is to determine the functional role of NEK2 in promoting cancer progression and to use this knowledge to develop novel therapies. The variability in survival of multiple myeloma patients ranges from only a few months to >10 years. We have previously shown that NEK2- expression is increased in multiple cancers including myeloma; higher levels of NEK2-expression induce cell rapid growth and resistance to multiple chemotherapeutics. This project builds upon our finding that when a specific gene (NEK2) that regulates the cell cycle is overexpressed, patients experience a clinically aggressive form and rapid death of myeloma and other cancers. We have made several striking discoveries supporting the hypothesis that NEK2 over-expression disrupts the normal cycle of tumor cell proliferation, resulting in poor survival for myeloma patients. Our goal to test the hypothesis will be accomplished by execution of three specific aims using both in vitro and in vivo models. Aim1: To examine the role of NEK2 in the development and progression of myeloma. We propose to evaluate whether myeloma cells with high-NEK2 expression are characterized with drug resistance in a large cohort of patients with myeloma at different stages; we will also test the growth and drug-resistance of primary myeloma cells with NEK2 high- or NEK2 low-expression in vitro and in vivo; we will introduce NEK2 into normal fibroblast cells and murine cancer-derived myeloma cell line that have low endogenous NEK2 expression, we will then analyze the effects of this alteration on cell transformation, cellular growth, and response to chemotherapeutic agents. Aim 2: to determine NEK2-mediated signaling pathways in cancer cell proliferation and survival. To achieve this goal, we will determine whether some cell growth related signaling pathways are required for NEK2-mediated cell growth and drug resistance in multiple myeloma. We will examine key substrates that directly interact with the NEK2 protein. Furthermore, gene expression profiling (GEP) will be performed on myeloma samples in remission and at relapse who also have GEP at baseline to identify genes that are regulated by NEK2 at different myeloma stages. Aim 3: to develop novel treatments based on targeting NEK2 or its signaling pathways. Through the screen of kinase inhibitor libraries, we have identified two small molecules that can specifically inhibit NEK2 kinase activity, and induce dramatic cancer cell death in vitro. We will use these molecules as a tool to explore their efficacy in killing myeloma cells in vivo. Inhibitors targeting these signaling pathways will be used alone or in combination with the current used chemotherapeutic drugs to evaluate their antimyeloma activities in vitro and in vivo.