Novel Targeted Therapy for CLL

描述（由申请人提供）：在西方世界近84,000例白血病中，b细胞慢性淋巴细胞白血病（B-CLL）是最常见的，约占所有成人白血病病例的30%。它的特点是不断积累的单克隆成熟B细胞。来自B-CLL患者的肿瘤细胞显示出更高的存活率，这是由于抑制细胞凋亡和参与细胞周期控制和细胞存活的基因改变。在评估B-CLL细胞中异常激活的信号通路时，我们发现Akt激酶是组成性激活的，Akt的过度刺激导致NFkB通路的激活，从而导致NO的产生增加并抑制细胞凋亡。由于B-CLL在至少有一个一级亲属患有CLL的人群中更常见，因此多年来人们都知道B-CLL存在遗传易感性。在B-CLL病例中记录的染色体畸变中，11q缺失包括PPP2R1B基因的一部分，该基因编码蛋白磷酸酶2a （PP2a）的A2恒定调节亚基。PP2a是一种众所周知的肿瘤抑制因子，由于11q缺失导致B-CLL细胞中PP2a活性降低，PP2a表达不足。PP2a在Akt、丝裂原活化蛋白激酶（MAPK） p38、JNK和ERK以及核因子kB（通过IkK）失活中的作用已得到证实。B-CLL细胞中PP2a活性的降低可能导致Akt信号传导异常，诱导型一氧化氮合酶（iNOS）的产生，以及其他在恶性B-CLL细胞中表现出来的效应。因此，药理激活PP2a可能为开发B-CLL治疗方法提供一种新的途径。Cognosci已经开发出一种新型的治疗肽，在体外和体内都具有有效的抗炎活性。在机制研究中，我们最近证明了这些肽抑制磷酸化和伴随的重要炎症信号蛋白的激活，包括p38、JNK、ERK MAPKs以及IkK、IkB和NFkB。通过对Cognosci化合物的作用机制分析，我们发现化合物处理导致PP2a活化，抑制信号转导通路，产生细胞因子、iNOS及其产物NO。在对几种COG化合物在患者原代CD19+/CD5+ B-CLL细胞中的初步评估中，我们发现其中一种化合物（COG112）对人CLL细胞具有高度和优先的细胞毒性，EC50为224 nM，对正常b细胞的EC50为20 μ m。我们拟确定COG112处理对B-CLL细胞关键信号转导蛋白磷酸化状态和PP2a活性的影响。我们还将在E5-TCL1转基因CLL小鼠模型中评估COG112的抗CLL活性。公共卫生相关性：在西方世界近84,000例白血病病例中，b细胞慢性淋巴细胞白血病（B-CLL）是最常见的，约占所有成人白血病病例的30%。它的特点是不断积累的单克隆成熟B细胞。来自B-CLL患者的肿瘤细胞显示出更高的存活率，这是由于抑制细胞凋亡和参与细胞周期控制和细胞存活的基因改变。在评估B-CLL细胞中异常激活的信号通路时，我们发现Akt激酶是组成性激活的，Akt的过度刺激导致NFkB通路的激活，从而导致NO的产生增加并抑制细胞凋亡。由于B-CLL在至少有一个一级亲属患有CLL的人群中更常见，因此多年来人们都知道B-CLL存在遗传易感性。在B-CLL病例中记录的染色体畸变中，11q缺失包括PPP2R1B基因的一部分，该基因编码蛋白磷酸酶2a （PP2a）的A2恒定调节亚基。PP2a是一种众所周知的肿瘤抑制因子，由于11q缺失导致B-CLL细胞中PP2a活性降低，PP2a表达不足。PP2a在Akt、丝裂原活化蛋白激酶（MAPK） p38、JNK和ERK以及核因子kB（通过IkK）失活中的作用已得到证实。B-CLL细胞中PP2a活性的降低可能导致Akt信号传导异常，诱导型一氧化氮合酶（iNOS）的产生，以及其他在恶性B-CLL细胞中表现出来的效应。因此，药理激活PP2a可能为开发B-CLL治疗方法提供一种新的途径。Cognosci已经开发出一种新型的治疗肽，在体外和体内都具有有效的抗炎活性。在机制研究中，我们最近证明了这些肽抑制磷酸化和伴随的重要炎症信号蛋白的激活，包括p38、JNK、ERK MAPKs以及IkK、IkB和NFkB。通过对Cognosci化合物的作用机制分析，我们发现化合物处理导致PP2a活化，抑制信号转导通路，产生细胞因子、iNOS及其产物NO。在对几种COG化合物在患者原代CD19+/CD5+ B-CLL细胞中的初步评估中，我们发现其中一种化合物（COG112）对人CLL细胞具有高度和优先的细胞毒性，EC50为224 nM，对正常b细胞的EC50为20 μ m。我们拟确定COG112处理对B-CLL细胞关键信号转导蛋白磷酸化状态和PP2a活性的影响。我们还将在E5-TCL1转基因CLL小鼠模型中评估COG112的抗CLL活性。

DESCRIPTION (provided by applicant): Of the nearly 84,000 cases of leukemia in the Western world, B-cell chronic lymphocytic leukemia (B-CLL) is the most common and accounts for approximately 30% of all adult leukemia cases. It is characterized by the relentless accumulation of monoclonal mature B cells. Tumor cells from B-CLL patients show increased survival rates that have been shown to be due to inhibited apoptosis and alterations of genes involved in cell cycle control and cell survival. When evaluating the signaling pathways that are aberrantly activated in B-CLL cells, it was demonstrated that the kinase Akt is constitutively activated and the overstimulation of Akt results in activation of the NFkB pathway that leads to increased production of NO and inhibited apoptosis. It has been known for many years that a genetic predisposition for B-CLL exists given that B-CLL occurs more commonly in people with at least one first degree relative with CLL. Among chromosomal aberrations that have been documented in B-CLL cases is a deletion at 11q that includes a portion of the PPP2R1B gene, which encodes the A2 constant regulatory subunit of Protein Phosphatase 2a (PP2a). PP2a is a commonly known tumor suppressor that is underexpressed as a result of the 11q deletion leading to decreased PP2a activity in B-CLL cells. The role of PP2a in deactivation of Akt, the mitogen activated protein kinases (MAPK) p38, JNK, and ERK, as well as Nuclear Factor kB (through IkK) is well established. Reduced PP2a activity in B-CLL cells would be expected to lead to aberrant signaling through Akt, production of inducible Nitric Oxide Synthase (iNOS), and other effects demonstrated in malignant B-CLL cells. Therefore, pharmacological activation of PP2a may provide a novel approach to development of B-CLL therapeutics. Cognosci has developed novel therapeutic peptides with potent anti-inflammatory activity in vitro and in vivo. In mechanistic studies we recently demonstrated that these peptides suppress phosphorylation and the accompanying activation of important inflammatory signaling proteins including p38, JNK, and ERK MAPKs as well as IkK, IkB, and NFkB. Upon analysis of the mechanism of action of the Cognosci compounds, we found that compound treatment results in activation of PP2a and suppression of signal transduction pathways and production of cytokines, iNOS and its product NO. During a preliminary evaluation of several COG compounds in primary CD19+/CD5+ B-CLL cells from patients, we discovered that one of these compounds, (COG112) is highly and preferentially cytotoxic for human CLL cells with an EC50 of 224 nM and an EC50 for normal B-cells of >20 uM. We propose to determine the effect of COG112 treatment on the phosphorylation state of key signal transduction proteins and PP2a activity in B-CLL cells. We will also evaluate COG112 for anti-CLL activity in the E5-TCL1 transgenic mouse model of CLL. PUBLIC HEALTH RELEVANCE: Of the nearly 84,000 cases of leukemia in the Western world, B-cell chronic lymphocytic leukemia (B-CLL) is the most common and accounts for approximately 30% of all adult leukemia cases. It is characterized by the relentless accumulation of monoclonal mature B cells. Tumor cells from B-CLL patients show increased survival rates that have been shown to be due to inhibited apoptosis and alterations of genes involved in cell cycle control and cell survival. When evaluating the signaling pathways that are aberrantly activated in B-CLL cells, it was demonstrated that the kinase Akt is constitutively activated and the overstimulation of Akt results in activation of the NFkB pathway that leads to increased production of NO and inhibited apoptosis. It has been known for many years that a genetic predisposition for B-CLL exists given that B-CLL occurs more commonly in people with at least one first degree relative with CLL. Among chromosomal aberrations that have been documented in B-CLL cases is a deletion at 11q that includes a portion of the PPP2R1B gene, which encodes the A2 constant regulatory subunit of Protein Phosphatase 2a (PP2a). PP2a is a commonly known tumor suppressor that is underexpressed as a result of the 11q deletion leading to decreased PP2a activity in B-CLL cells. The role of PP2a in deactivation of Akt, the mitogen activated protein kinases (MAPK) p38, JNK, and ERK, as well as Nuclear Factor kB (through IkK) is well established. Reduced PP2a activity in B-CLL cells would be expected to lead to aberrant signaling through Akt, production of inducible Nitric Oxide Synthase (iNOS), and other effects demonstrated in malignant B-CLL cells. Therefore, pharmacological activation of PP2a may provide a novel approach to development of B-CLL therapeutics. Cognosci has developed novel therapeutic peptides with potent anti-inflammatory activity in vitro and in vivo. In mechanistic studies we recently demonstrated that these peptides suppress phosphorylation and the accompanying activation of important inflammatory signaling proteins including p38, JNK, and ERK MAPKs as well as IkK, IkB, and NFkB. Upon analysis of the mechanism of action of the Cognosci compounds, we found that compound treatment results in activation of PP2a and suppression of signal transduction pathways and production of cytokines, iNOS and its product NO. During a preliminary evaluation of several COG compounds in primary CD19+/CD5+ B-CLL cells from patients, we discovered that one of these compounds, (COG112) is highly and preferentially cytotoxic for human CLL cells with an EC50 of 224 nM and an EC50 for normal B-cells of >20 uM. We propose to determine the effect of COG112 treatment on the phosphorylation state of key signal transduction proteins and PP2a activity in B-CLL cells. We will also evaluate COG112 for anti-CLL activity in the E5-TCL1 transgenic mouse model of CLL.