Effect of inflammation on JAK2 mutant evolution in the hematopoietic system: mathematical models and experiments

项目摘要/摘要 骨髓增生性肿瘤(MPN)是一种以克隆性生长为特征的血液系统恶性肿瘤。 具有体细胞获得性突变的造血细胞，最常见的是JAK2(JAK2V617F)，这导致 髓系细胞产生过多。早期MPN患者可自发进展为 骨髓纤维化，是疾病的一个更具侵袭性的阶段，平均存活率为两年。此外， MPN患者患急性髓系白血病(AML)的风险很大。传统的方法是 MPN的治疗方法很简单，就是用阿司匹林降低血栓风险，控制症状，观察 疾病的发展。治疗干预的重点是晚期疾病患者，主要是由于 缺乏目前可用的阻止进展的治疗方法。因此，有必要进行干预，以影响 MPN的疾病进展。Fleischman博士的实验室与 数学模型师Komarova和Wodarz表示，炎症可以加快血管的生长速度 JAK2V617F突变细胞相对于JAK2WT细胞，这可能会对 处于动态平衡状态的突变细胞的进化。这暗示了一种新的早期治疗方式的可能性 MPN阶段，JAK2V617F突变体的进化命运发生改变，疾病进展延迟 或者停下来。这项提案的总体目标是调查如何实现这一目标。在目标1中，实验是 提出了JAK2WT和JAK2V617F突变细胞在有无隔离情况下的动力学文件 用于模型构建和参数化目的的炎症。我们还将审问 JAK2V617F突变体对炎症的差异反应的细胞内机制。在AIM 2我们将进行JAK2WT和JAK2V617F突变细胞在小鼠模型中与 而且没有发炎。这将量化突变体的数量如何影响野生生物的动力学参数。 类型的细胞，这一点很重要，因为我们知道突变体本身会增加炎症，因此 改变动态。在目标3中，我们将测量一组现有药物对细胞动力学参数的影响 并使用我们的模型来预测将导致突变细胞减少的组合和给药计划。 将探索许多治疗方案(按顺序和组合)，最有希望的治疗方案 该模型预测的方法将进行实验测试。这可以更好地识别当前未知的 利用现有药物的方式。在更具探索性的层面上，经过验证的数学模型可以 建议以哪个参数(S)为目标，以哪些方式使治疗比目前可以做的更有效。 这些信息将有助于开发未来的治疗方法并指导药物发现，并可能 转化为未来的临床试验。

PROJECT SUMMARY/ABSTRACT Myeloproliferative neoplasm (MPN) is a hematologic malignancy characterized by the clonal outgrowth of hematopoietic cells with a somatically acquired mutation most commonly in JAK2 (JAK2V617F), which leads to excessive production of myeloid lineage cells. Patients with early stage MPN can spontaneously progress to myelofibrosis, a more aggressive stage of the disease with an average survival rate of two years. Moreover, MPN patients have a significant risk of developing acute myeloid leukemia (AML). The traditional approach to therapy in MPN is simply to reduce the risk of blood clots with aspirin, manage symptoms, and observe for progression of the disease. Therapeutic intervention is focused on patients with late stage disease, mostly due to the lack of currently available therapies that halt progression. There is thus a need for interventions that impact disease progression in MPN. Preliminary work by the laboratory of Dr. Fleischman, in collaboration with mathematical modelers Komarova and Wodarz, has shown that inflammation can accelerate the growth rate of JAK2V617F mutant cells relative to JAK2WT cells, and that this can potentially have a variety of consequences for the evolution of mutant cells at homeostasis. This suggests the possibility of a new treatment modality for early stage MPN, in which the evolutionary fate of the JAK2V617F mutants is altered and disease progression is delayed or halted. The overall goal of this proposal is to investigate how this can be achieved. In Aim 1, experiments are proposed that document the dynamics of JAK2WT and JAK2V617F mutant cells in isolation with and without inflammation for the purposes of model construction and parameterization. We will also interrogate the intracellular mechanisms responsible for the differential response of JAK2V617F mutants to inflammation. In Aim 2 we will perform experiments in which JAK2WT and JAK2V617F mutant cells are combined in mouse models with and without inflammation. This will quantify how the number of mutants influence the kinetic parameters of wild- type cells, which is important because we know that mutants themselves can increase inflammation and hence alter the dynamics. In Aim 3 we will measure how a panel of existing drugs impact the kinetic parameters of cells and use our model to predict combinations and dosing schedules that will lead to diminution of the mutant cells. Many treatment scenarios (in sequence and in combination) will be explored, and the most promising therapeutic approaches predicted by the model will be tested experimentally. This can identify better and currently unknown ways in which to utilize existing drugs. On a more exploratory level, the validated mathematical model can suggest which parameter(s) to target in which ways to make treatment more efficient than can be currently done. This information would facilitate development of future treatments and guide drug discovery and could be translated into a future clinical trial.