Notch and GATA-3 as novel therapeutic targets in T-cell lymphomas

项目摘要 快速疾病进展和化疗耐药疾病是最常见的 常见的T细胞淋巴瘤（TCL），这些患者中的大多数最终将死于进行性 确诊后三年内发病。只有少数（≤10%）患者将实现持久缓解 由于促进TCL进展和化疗耐药性的机制尚不清楚， 没有明确的理解和治疗策略来克服它们。我们最近发现T- 细胞转录因子加塔-3鉴定了分子上、遗传上和临床上不同的TCL亚群， 对化疗有很强的抵抗力我们还证明了Notch激活在TCL中普遍存在， 阻断Notch可抑制TCL增殖和Notch靶基因加塔-3的表达， 问题研究基因和药理学功能丧失（和功能获得）策略在 遗传多样的TCL细胞，随后证明加塔-3直接赋予抗性， 以细胞自主的方式进行化疗。此外，淋巴瘤相关的巨噬细胞（LAM）内， 肿瘤微环境（TME）促进化疗耐药，加塔-3依赖性细胞因子调节 他们的功能极化，突出了一个额外的非细胞自主机制，加塔-3依赖 化疗耐药性因此，迫切需要鉴定调节加塔-3表达的因子， 在这些激进的TCL中发挥作用。在缺乏这些知识的情况下，治疗性药物的开发 削弱加塔-3依赖性转录调控并改善这些TCL结果的策略 仍将难以捉摸我们的长期目标是了解推动TCL的根本机制 发病机制，并促进其抵抗目前可用的治疗。在这样做的过程中，我们希望发展 合理设计的治疗策略，将克服化疗耐药性的挑战， 改善患有这些TCL患者的结果。我们在此应用程序中的总体目标是评估 Notch信号传导在T细胞淋巴瘤发生中的作用，并确定最佳加塔-3的要求 DNA结合和转录调控。这些将通过解决我们的中心假设来实现， Notch和加塔-3促进TCL进展和对化疗的抵抗。除了身体健康之外- 基于我们自己的初步数据，我们的中心假设与我们目前的假设完全一致。 了解TCL的遗传景观和分子发病机制，并具有重要的治疗意义 影响

Project Abstract Rapid disease progression and chemotherapy resistant disease are frequently observed among the most common T-cell lymphomas (TCL) and the majority of these patients will ultimately succumb to progressive disease within three years of diagnosis. Only a minority (≤10%) of patients will achieve a durable remission with novel agents, as the mechanisms promoting TCL progression and chemotherapy resistance are poorly understood and therapeutic strategies to overcome them are not defined. We have recently shown that the T- cell transcription factor GATA-3 identifies a molecularly, genetically, and clinically distinct subset of TCL that are highly resistant to chemotherapy. We have also demonstrated that Notch activation is prevalent in the TCL, and Notch blockade inhibits both TCL proliferation and GATA-3 expression, a Notch target gene, in preliminary studies. Genetic and pharmacologic loss-of-function (and gain-of-function) strategies were performed in genetically diverse TCL cells and subsequently demonstrated that GATA-3 directly confers resistance to chemotherapy in a cell-autonomous fashion. In addition, lymphoma-associated macrophages (LAM) within the tumor microenvironment (TME) promote chemotherapy resistance, and GATA-3 dependent cytokines regulate their functional polarization, highlighting an additional non-cell-autonomous mechanism for GATA-3-dependent chemotherapy resistance. Thus, there is a critical need to identify factors regulating GATA-3 expression and function in these aggressive TCL. In the absence of such knowledge, the development of therapeutic strategies that impair GATA-3-dependent transcriptional regulation and improve outcomes among these TCL will remain elusive. Our long-term goals are to understand the fundamental mechanisms that drive TCL pathogenesis and promote their resistance to currently available therapies. In doing so, we hope to develop rationally designed therapeutic strategies that will overcome the challenge of chemotherapy resistance and improve outcomes for patients afflicted with these TCL. Our overall objectives in this application are to evaluate the role of Notch signaling in T-cell lymphomagenesis and to identify the requirements for optimal GATA-3 DNA binding and transcriptional regulation. These will be achieved by addressing our central hypothesis that Notch and GATA-3 promote TCL progression and resistance to chemotherapy. In addition to being well- grounded in our own preliminary data, our central hypothesis is entirely consistent with our current understanding of the genetic landscape and molecular pathogenesis of the TCL and has significant therapeutic implications.