A Novel Anoikis Effector that Drives Ovarian Cancer Metastasis

项目摘要 正常细胞依赖于细胞外基质（ECM）存活，并且当细胞凋亡时经历细胞凋亡。 它们失去与ECM的接触-一种称为失巢凋亡的现象。获得对失巢凋亡的抵抗力是一个关键 这一步骤对卵巢癌的转移进展有显著贡献。然而，这些因素和 在卵巢癌中赋予失巢凋亡抗性的调节途径在很大程度上仍然未知。因此，为了识别 我们进行了一个无偏见的基于基因组的RNAi筛选， 将ATAD 2鉴定为一种赋予高级别浆液性卵巢癌（HGS-1）失巢凋亡抗性的新因子。 OvCa）细胞。此外，我们记录了ATAD 2在HGS-OvCa患者样品中过表达， 过度表达预测显著降低的总生存期（OS）和无进展生存期（PFS）。我们 作为这项研究建议基础的初步数据提供了强有力的证据， 前提是ATAD 2是抗失巢凋亡所必需的，因此是HGS-OvCa转移的潜在驱动因素。 本研究提案的总体目标是确定ATAD 2在促进HGS-1中的体内作用。 OvCa转移，了解其作用机制并评估ATAD 2的体内药理学靶向 用于转移性HGS-OvCa治疗。具体而言，目标1实验将确定ATAD 2作为驱动程序的作用 的HGS-OvCa转移，并评估其作为转移性HGS-OvCa癌症治疗的药物靶标。我们将使用 基因方法和高效选择性ATAD 2小分子抑制剂BAY-850 本发明涉及用于实现目的1的目标的药理学方法。对于遗传方法，我们将使用互补 基于HGS-OvCa细胞的原位异种移植的器官特异性和自发转移模型。为 除了器官特异性和自发性HGS-OvCa小鼠模型外， 转移，我们还将使用具有完整的先天性和过继性的新型人源化HGS-OvCa异种移植物模型。 人体免疫系统目的2，实验将确定ATAD 2赋予失巢凋亡的机制 并促进HGS-OvCa转移。在初步研究中，我们发现ATAD 2抑制了 促凋亡基因BAD的表达，这是ATAD 2抑制诱导的抗失巢凋亡所必需的。 基于这些结果，我们将确定BAD作为ATAD 2诱导的失巢凋亡的下游介质的作用。 耐药和HGS-OvCa转移。实验方法将利用生物化学、遗传学、细胞 基于培养的方法和失巢凋亡抗性和HGS-OvCa转移的体内小鼠模型。特别是， 我们将使用基于原位HGS-OvCa细胞移植的器官特异性和自发转移模型。 总的来说，这些结果将确定一种新的药物依赖途径，通过促进失巢凋亡， 耐药促进HGS-OvCa转移，因此可以靶向有效治疗高度侵袭性的 转移性HGS-OvCa。

PROJECT SUMMARY Normal cells are dependent upon the extracellular cell matrix (ECM) for survival, and undergo apoptosis when they lose contact with the ECM – a phenomenon termed anoikis. The acquisition of anoikis resistance is a critical step that contributes prominently to the metastatic progression in ovarian cancer. However, the factors and regulatory pathways that confer anoikis resistance in ovarian cancer remain largely unknown. Thus, to identify factors that confer anoikis resistance, we performed an unbiased druggable genome-based RNAi screen and identified ATAD2 as a novel factor that confers anoikis resistance in high-grade serous ovarian cancer (HGS- OvCa) cells. Additionally, we document that ATAD2 is overexpressed in HGS-OvCa patient samples and its overexpression predicts significantly reduced overall survival (OS) and progression-free survival (PFS). Our preliminary data that makes the basis of this research proposal provides strong evidence supporting the scientific premise that ATAD2 is necessary for anoikis resistance and thus is a potential driver of HGS-OvCa metastasis. The overall objective for this research proposal is to determine the in vivo role of ATAD2 in facilitating HGS- OvCa metastasis, understand its mechanism-of-action and evaluate in vivo pharmacological targeting of ATAD2 for metastatic HGS-OvCa therapy. Specifically, Aim 1 experiments will determine the role of ATAD2 as a driver of HGS-OvCa metastasis and evaluate it as a drug target for metastatic HGS-OvCa cancer therapy. We will use both genetic approach and highly-effective and selective ATAD2 small molecule inhibitor BAY-850-based pharmacological approach for achieving the goals of Aim 1. For genetic approach, we will use complementary organ-specific and spontaneous metastasis models based on orthotopic xenograft of HGS-OvCa cells. For pharmacological approach, in addition to organ-specific and spontaneous mouse models of HGS-OvCa metastasis, we will also use a novel humanized HGS-OvCa xenograft model with intact innate and adoptive human immune system. Aim 2, experiments will determine the mechanism by which ATAD2 confers anoikis resistance and promote HGS-OvCa metastasis. In preliminary studies, we found that ATAD2 represses the expression of pro-apoptotic gene BAD, which is necessary for ATAD2 inhibition-induced anoikis resistance. Based on these results, we will ascertain the role of BAD as a downstream mediator of ATAD2-indued anoikis resistance and HGS-OvCa metastasis. The experimental approaches will utilize biochemical, genetic, cell culture-based methods and in vivo mouse model of anoikis resistance and HGS-OvCa metastasis. In particular, we will use organ-specific and spontaneous metastasis model based on orthotopic HGS-OvCa cells transplant. Collectively, these results will identify a novel druggable dependency pathway that via promoting anoikis resistance facilitates HGS-OvCa metastasis, and thus can be targeted for effectively treating highly aggressive metastatic HGS-OvCa.