Studying the initiation, progression and therapy of lung cancer in mouse models

 描述(申请人提供)：肺癌是一种全球性疾病，导致全球140万人死亡，仅今年美国就有16万人死亡。尽管临床形势严峻，但癌症遗传学已经揭示，肺癌可以根据驱动癌基因突变分为基因定义的亚集，这些亚集反过来又可以作为肺癌患者临床部署新的一线通路靶向治疗的预测性生物标志物。然而，到目前为止，只有少数此类患者从这些进展中受益，因此大多数患者的治疗选择仍然很差，仅限于传统的方法，包括手术、放射和/或常规化疗，这些方法对肿瘤细胞无效，对正常细胞有毒。这项研究的主要长期目标是帮助部署合理的、循证的治疗策略来治疗肺癌患者。然而，这项提议的直接目标是从机械上定义平行通路，如WnT→ç-catenin→c-myc或PI3‘-→→PDK AKT信号，如何与致癌基因KrasG12D或BRAFV600E在肺癌的发生和维持中协同作用。为此，我们将使用：最先进的基因工程小鼠肺癌模型；由相关基因异常推动其异常行为的肺癌衍生细胞系；靶向治疗药物，其中许多药物正在癌症临床试验中，其中一种正在肺癌中进行专门测试；以及一种创新的转座子突变系统，该系统可以同时诱导肺癌进展并确定其潜在的遗传原因。在此资助的前一个周期发表的研究的坚实基础上，在目标1中，我们将确定肿瘤细胞自主机制，在肺癌的发生和维持中，Wnt→？-catenin信号与致癌基因KrasG12D或BRAFV600E合作。在目标2中，我们将探索PI3‘-激酶信号促进BRAFV600E诱导的早期和晚期肺肿瘤增殖扩张和维持的机制。BRAFV600E诱导的肺肿瘤保持一致良性，除非协同的基因组事件引发恶性进展。在目标3中，文件使用睡美人(SB)转座子突变来促进BRAFV600E驱动的肺癌的进展。确定的遗传进展因子将通过慢病毒介导的cdna表达或体内CRISPR/Cas9介导的小鼠肺内肿瘤抑制基因沉默来验证。此外，我们将挖掘TCGA肺腺癌基因组、RNA测序和RPPA数据库，以证明在我们的SB筛查中涉及的基因与真正的人类肺癌直接相关。最后，虽然这项建议主要集中在肺癌发生中的基因合作研究，但我们将测试BRAFV600E、WNT或PI3‘-激酶信号的新型通路靶向抑制物的抗肿瘤效果，这些信号可能对设计和评估新的通路靶向策略具有重要的翻译意义，以治疗这种普遍存在的、破坏性的和鲜为人知的疾病。

 DESCRIPTION (provided by applicant): Lung cancer is a global scourge responsible for 1.4 million deaths worldwide and ~160,000 deaths in the USA this year alone. Despite the grim clinical picture, cancer genetics has revealed that lung cancers can be divided into genetically-defined subsets based on driver oncogene mutations that, in turn, serve as predictive biomarkers for the clinical deployment of new first-line pathway-targeted therapies in lung cancer patients. However, to date, only a minority of such patients have benefitted from these advances such that treatment options for most patients remain poor and are limited to conventional approaches including surgery, radiation, and/or conventional chemotherapy that are ineffective against tumor cells and toxic to normal cells. The overarching, long-term goal of this research is to aid the deployment of rational, evidence-based therapeutic strategies to treat lung cancer patients. However, the immediate objectives of this proposal are to mechanistically define how parallel pathways, such as WNT→ß-catenin→c-MYC or PI3'-kinase→PDK→AKT signaling, cooperate with oncogenic KRASG12D or BRAFV600E in the genesis and maintenance of lung cancer. To do so we will use: State-of-the-art genetically engineered mouse models of lung cancer; Lung cancer- derived cell lines whose aberrant behavior is driven by relevant genetic abnormalities; Pathway-targeted therapeutics, many of which are in cancer clinical trials and one of which is specifically being tested in lung cancer and; An innovative transposon mutagenesis system to simultaneously elicit lung cancer progression and identify its underlying genetic cause. Building on a solid foundation of studies published in the previous cycle of this grant, in Aim 1 we will identify the tumor cell autonomous mechanisms by which WNT→ß-catenin signaling cooperates with oncogenic KRASG12D or BRAFV600E in the genesis and maintenance of lung cancer. In Aim 2 we will explore the mechanisms by which PI3'-kinase signaling promotes the proliferative expansion and maintenance of both early- and late-stage BRAFV600E-induced lung tumors. BRAFV600E-induced lung tumors remain uniformly benign unless cooperating genomic events unleash malignant progression. In Aim 3 document the use of Sleeping Beauty (SB) transposon mutagenesis to promote progression of BRAFV600E- driven lung cancers. Genetic progression factors identified will be validated using lentivirus-mediated cDNA expression or by in vivo CRISPR/Cas9-mediated tumor suppressor gene silencing in the mouse lung. Moreover, we will mine the TCGA lung adenocarcinoma genome, RNA sequencing and RPPA databases to credential genes implicated in our SB screen in mice as being directly relevant to bona fide human lung cancer. Finally, although this proposal is focused primarily on studies of genetic cooperation in the genesis of lung cancer, we will test the anti-tumor effects of novel pathway-targeted inhibitors of BRAFV600E, WNT or PI3'- kinase signaling that are likely to have important translational implications for the design and evaluation of new pathway-targeted strategies to treat patients with this ubiquitous, devastating and poorly understood disease.