Mechanisms and Vulnerabilities of SWI/SNF chromatin remodeling complex mutant lung cancer

项目摘要 肺癌是一种毁灭性的疾病，仍然是癌症死亡的首要原因。尽管最近 进展，大多数肺癌患者缺乏有效的治疗选择，突显出迫切需要 用于其他治疗方法。基因组学研究已经确定了该基因亚基的频繁突变。 包括SMARCA4和ARID1A在内的SWI/SNF染色质重构复合体在非小细胞肺癌中的表达 在晚期疾病中的发生率高达33%，使其成为肺部最常见的突变复合体 癌症。我们最近证明了SMARCA4在小鼠体内起到了真正的肿瘤抑制作用，并进行了合作 P53缺失，Kras激活。重要的是，SMARCA4突变的癌细胞对 新型小分子iacs-10759对氧化磷酸化的抑制作用。从机械上讲，我们 研究表明，SMARCA4缺陷细胞对能量压力的转录反应迟钝，产生了 与治疗相关的脆弱性。 综合这些观察结果，我们假设使用IacS-10759抑制氧磷酸盐是一种 SWI/SNF复合体突变肺癌的诱人治疗策略。的主要目标 本研究旨在揭示SWI/SNF突变体中代谢重排的机制基础。 提供临床前证据以指导未来对SWI/snf突变肺患者进行IacS-10759的临床研究 癌症。由于肺癌独特的微环境，包括局部高氧分压，因此治疗势在必行。 目的：研究以代谢为靶点的治疗药物。因此，我们将测试iacs-10759在 肺癌的宝石模型。此外，PDX模型已成为帮助指导治疗的强大工具 战略。因此，我们建议确定不同SWI/SNF突变体PDX中OXPHOS抑制的可能性 模型系统。虽然我们的初步数据表明，IacS-10759治疗会导致肿瘤生长受到抑制， 协同组合策略有望在效果上更具优势。因此，我们建议确定 通过化学遗传学筛选与iacs-10759协同的最佳组合药物。在这里，我们将使用 CRISPR-Cas9和针对FDA批准的药物靶向的基因的定制设计的指南RNA文库 (FDAome)。我们将通过在体内进行一对一药物联合研究来验证筛查结果。 最后，我们的初步数据表明，主要基因pgc1α的表达需要SMARCA2 SMARCA4突变细胞线粒体生物发生和OXPHOS的转录调控。我们从 我们已发表的工作认为PgC1SARCA4缺陷细胞中α是必需的。因此，我们假设SMARCA2 是一种生存因子，也是依赖于α的SMARCA4缺陷细胞中代谢重连的主要驱动力 举止。综上所述，我们的研究有望提供有关代谢失调的机械性见解。 Swi/Snf突变的肺癌，为今后OXPHOS抑制剂的临床开发奠定基础 作为治疗学。

Project Summary Lung cancer is a devastating disease that remains the top cause of cancer mortality. Despite recent advances, the majority of patients with lung cancer lack effective therapeutic options, underscoring the dire need for additional treatment approaches. Genomic studies have identified frequent mutations in subunits of the SWI/SNF chromatin remodeling complex including SMARCA4 and ARID1A in non-small cell lung cancer with a frequency of up to 33% in advanced stage disease, making it the most frequently mutated complex in lung cancer. We recently demonstrated that Smarca4 acts as a bona fide tumor suppressor in mice and cooperates with p53 loss and Kras activation. Importantly, SMARCA4 mutant cancer cells have heightened sensitivity to inhibition of oxidative phosphorylation (OXPHOS) by a novel small molecule, IACS-10759. Mechanistically, we showed that SMARCA4-deficient cells have a blunted transcriptional response to energy stress creating a therapeutically relevant vulnerability. Taking these observations together, we hypothesize that OXPHOS inhibition using IACS-10759 is an attractive therapeutic strategy for lung cancers with mutations in the SWI/SNF complex. The major objectives of the proposed study are to discover the mechanistic basis of the metabolic rewiring in SWI/SNF mutants and provide preclinical evidence to guide future clinical study of IACS-10759 in patients with SWI/SNF mutant lung cancer. Due to the unique microenvironment of lung cancer including high local oxygen tension, it is imperative to study therapeutic agents targeting metabolism orthotopically. Hence, we will test efficacy of IACS-10759 in GEM models of lung cancer. Further, PDX models have emerged as powerful tools to help guide treatment strategies. Thus, we propose to determine the potential of OXPHOS inhibition in various SWI/SNF mutant PDX model systems. While our preliminary data indicates that IACS-10759 treatment leads to tumor growth inhibition, synergistic combination strategies are expected to be even superior in efficacy. Thus, we propose to identify optimal combination agents that synergize with IACS-10759 by using a chemo-genetic screen. Here, we will use CRISPR-Cas9 and a custom designed library of guide RNAs against genes targeted by FDA approved drugs (FDAome). We will validate the results of the screen by performing one-on-one drug combination studies in vivo. Finally, our preliminary data suggests that SMARCA2 is required for expression of PGC1α, a master transcriptional regulator of mitochondrial biogenesis and OXPHOS, in SMARCA4 mutant cells. We know from our published work that PGC1α is essential in SMARCA4 deficient cells. Thus we hypothesize that SMARCA2 is a survival factor and a major driver of metabolic rewiring in SMARCA4 deficient cells in a PGC1α dependent manner. In conclusion, our study is expected to provide mechanistic insight into the metabolic dysregulation of SWI/SNF mutant lung cancers and lay the foundation for future clinical development of the OXPHOS inhibitors as therapeutics.