THE ROLE OF POLYCOMB ASSOCIATED LONG NON-CODING RNAS IN LUNG CANCER METASTASIS

尽管我们对原发肺肿瘤的理解取得了进展，但推动进展的机制 从原发癌到转移性肺癌的特征仍然很差。到目前为止，肺癌研究已经 主要集中在蛋白质编码基因的失调，从而低估了 长的非编码RNA(LncRNAs)。由于最近的技术进步，我们的实验室第一个发现了120 LncRNAs，其中35个以前没有注释，区分转移组织和良性和 原发肿瘤，称为转移相关肺癌(MALL)。因此，从长远来看， 这项建议的目的是了解购物中心如何促进肺转移进展。 癌症。我们目前对lncRNAs如何在癌症中发挥作用的了解仍处于初级阶段。然而，有几个 研究表明，lncRNAs可能是癌症生物学中的主要调节者，通常与染色质结合。 修饰复合体并引导它们在整个基因组中调节基因表达。支持这一点， 以Polycomb为靶点的转移性肿瘤富含差异表达的蛋白编码基因 抑制性复合体2(PRC2)。在肺癌中，研究表明，PRC2的催化亚单位EZH2(和 H3K27甲基酶)过度表达，与不良预后相关，促进肿瘤进展，以及 表观遗传学抑制基因以促进转移。作为概念证明，我们发现最多的是- 转移性肿瘤中受调控的lncRNA与EZH2，MALL-1相互作用，促进细胞迁移和 体外侵袭，改变上皮-间充质转化(EMT)标志物的表达，并协同作用 抑制与患者转移相关的众所周知的PRC2靶基因。这是一种强有力的 我们假设购物中心与PRC2相互作用以表观遗传方式调节基因以促进 转移瘤。为了继续我们的假设，在目标1中，我们将优化在以下过程中改变的商场的景观 在更大的独立患者队列中的转移进展。我们还将把购物中心牵涉到表观遗传 通过优先考虑与PRC2持续互动的购物中心进行监管。在目标2中，我们将评估具体的 PRC2和MALL之间的相互作用位点是促进攻击性表型和表观遗传学所必需的 调控肿瘤转移相关基因。在目标3中，我们将确认与PRC2关联的购物中心进行促销 体内转移以及能否在治疗上被抑制。我们的研究将产生很大的整体影响 在lncRNA肿瘤生物学领域，通过定义在转移中改变的商场的景观，提供 对商场依赖的表观遗传调控的机械性见解，并将商场与转移瘤联系起来 体外和体内的表型。由于许多购物中心都是跨实体肿瘤改变的，他们可能保存了 调节作用，从而扩大了这项研究的影响，超出肺癌。我们的研究也有 翻译的含义，因为即使发现一个可以作为治疗靶点的购物中心也可以 为商场的治疗操作开辟新的途径，以改变肺癌的治疗。

Despite advances in our understanding of primary lung oncogenesis, the mechanisms driving the progression from primary to metastatic lung cancer remain poorly characterized. To date lung cancer research has primarily focused on the dysregulation of protein-coding genes thereby under-representing the emerging role of long non-coding RNAs (lncRNAs). Due to recent technological advances our lab was the first to discover 120 lncRNAs, of which 35 were previously unannotated, that differentiate metastatic tissues from benign and primary tumors, termed Metastasis Associated Lung cancer LncRNAs (MALLs). Therefore, the long-term goal of this proposal is to understand how MALLs contribute to the metastatic progression of lung cancer. Our current understanding of how lncRNAs function in cancer is still in its infancy. However, several examples indicate that lncRNAs may be master regulators in cancer biology, typically binding with chromatin modifying complexes and guiding them throughout the genome to regulate gene expression. Supporting this, metastatic tumors were enriched for differentially expressed protein-coding genes targeted by Polycomb Repressive Complex 2 (PRC2). In lung cancer, studies show that the catalytic subunit of PRC2, EZH2 (an H3K27 methylase), is overexpressed, associates with poor prognosis, promotes tumor progression, and epigenetically represses genes to promote metastasis. As proof of concept, we found that the most up- regulated lncRNA in metastatic tumors that interacts with EZH2, MALL-1, promotes cellular migration and invasion in vitro, alters expression of epithelial-mesenchymal transition (EMT) markers, and cooperatively represses well-known PRC2 target genes associated with metastasis in patients. This serves as a strong rationale for our hypothesis that MALLs interact with PRC2 to epigenetically regulate genes to promote metastases. To pursue our hypothesis, in Aim 1 we will refine the landscape of MALLs that are altered during metastatic progression across a larger independent patient cohort. We will also implicate MALLs in epigenetic regulation by prioritizing MALLs that consistently interact with PRC2. In Aim 2 we will assess specific interaction sites between a PRC2 and MALL necessary to promote aggressive phenotypes and epigenetically regulate genes involved in metastasis. In Aim 3 we will confirm that a PRC2-associating MALL promotes metastasis in vivo and whether it can be inhibited therapeutically. Our studies will have a large overall impact on the field of lncRNA tumor biology by defining the landscape of MALLs altered in metastasis, providing mechanistic insights into MALL-dependent epigenetic regulation, and associating MALLs with metastatic phenotypes in vitro and in vivo. Since many MALLs are altered across solid tumors they may have conserved regulatory roles thereby broadening the impact of this study beyond lung cancer. Our study also has translational implications as the discovery of even a single MALL that could serve as a therapeutic target can spur new avenues for therapeutic manipulation of MALLs to transform lung cancer treatment.