Understanding intrinsic resistance to direct KRAS inhibition in colorectal cancers

了解结直肠癌对直接 KRAS 抑制的内在抵抗

• 批准号: 10542813
• 负责人: John D Gordan
• 金额: $ 51.59万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-01 至 2026-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10542813
• 关键词: AXIN2 gene; BRAF gene; CRISPR interference; CTNNB1 gene; Cancer Biology; Cancer Etiology; Cancer Model; Cell Culture Techniques; Cell Line; Cell Proliferation; Cells; Cessation of life; Cholangiocarcinoma; Clinical Data; Clinical Trials; Clustered Regularly Interspaced Short Palindromic Repeats; Colorectal; Colorectal Cancer; Combined Modality Therapy; Complex; Data; Dependence; Development; Down-Regulation; Drug Combinations; Drug resistance; Engineering; Exposure to; Feedback; Gene Expression; Genes; Genetic Transcription; Genomic approach; Human; In Vitro; Individual; Inferior; KRAS oncogenesis; KRAS2 gene; LGR5 gene; Laboratories; Link; Malignant Neoplasms; Malignant neoplasm of lung; Maps; Mediator; Mitogen-Activated Protein Kinases; Modeling; Mutation; Non-Small-Cell Lung Carcinoma; Oncogenes; Oncogenic; Organoids; Outcome; Output; PIK3CA gene; Pancreatic Ductal Adenocarcinoma; Pathway interactions; Patients; Pharmaceutical Preparations; Phosphotransferases; Porcupines; Proliferating; Proteomics; Recurrence; Refractory; Regimen; Regulation; Resistance; Role; Signal Transduction; Skin; Tankyrase; Testing; Tissues; Toxic effect; Translations; Tumor Cell Line; United States; WNT Signaling Pathway; Work; cancer cell; cancer genomics; colon cancer cell line; colon cancer patients; colorectal cancer treatment; functional genomics; genomic data; improved; in vivo; inhibitor; interest; knock-down; melanoma; metastatic colorectal; mutant; new technology; novel strategies; novel therapeutics; patient derived xenograft model; patient population; programs; resistance mechanism; response; small molecule; small molecule inhibitor; synergism; systemic toxicity; targeted agent; targeted treatment; tool; transcription factor; treatment strategy; tumor; tumor growth

PROJECT SUMMARY/ABSTRACT Metastatic colorectal cancers (CRC) are the second leading cause of cancer death in the US. While advances in targeted therapies have transformed the treatment of many cancers, CRC has proven largely refractory to this approach. Thus, while agents targeting BRAFV600E and the KRASG12C mutation have dramatically improved the treatment of lung cancer and melanoma, they have only shown limited impact in CRC. CTNNB1 transcription is upregulated in >75% of CRC via APC inactivation and other mutations. As CTNNB1 is a common mediator of drug resistance and has been shown to be sufficient to maintain CRC proliferation, we hypothesize that it is a key mediator of intrinsic resistance to KRAS inhibition in CRC. Although multiple agents target CTNNB1 regulation via the WNT pathway, these have proven too toxic for human use to date. Thus, we have used proteomics to map the signaling response to KRASG12C inhibition in CRC cell lines and kinome-wide knockdown to identify kinases whose suppression synergizes with KRASG12C inhibition. By integrating these two approaches, we were able to uncover several kinases that function as signaling links between KRAS and CTNNB1, and whose inhibition synergizes with direct KRAS inhibition to reduce CTNNB1 target gene expression. As KRASG12C inhibitors do not impact normal KRAS signaling, this exciting preliminary data suggests that we may be able to preferentially downregulate CTNNB1 in tumors without systemic toxicity. We will build on this key preliminary data in this project: In Aim 1, we will expand our analysis of the kinase response to KRASG12C inhibition to additional CRC cell lines and the assess the impact of key kinases on CTNNB1 transcription. In Aim 2, we will use CRISPR in patient-derived xenografts (PDX) to circumvent the limitations of available small molecules to validate the role of CTNNB1 in APC-mutant CRC PDX. We will further use CRISPR or small molecules (when available) to test kinases already found to modulate CTNNB1 or emerging from Aim 1 in CRC treatment models and to determine their role in in vivo CRC biology. Finally, in Aim 3 we will develop KRASG12C CRC organoid and cell line models with mutations in PIK3CA, a common CRC mutation that co-occurs with KRAS mutations and is likely to cause resistance to KRASG12C inhibitors, but for which there are no models currently available. These tools will allow us to stratify the impact of PIK3CA mutation on our current treatment strategies and to optimize a regimen engineered specifically for this combination of mutations. This rigorous study of KRAS-driven signaling in CRC leverages new small molecules and robust quantitative approaches to unmask links between KRAS and the mechanisms that support CRC after KRAS inhibition. Uncovering the basis of resistance to direct KRAS inhibition in CRC will yield rational combination strategies primed for translation into clinical trials.

项目摘要/摘要 转移性结直肠癌(CRC)是美国癌症死亡的第二大原因。在前进的同时 在靶向治疗改变了许多癌症的治疗方面，CRC已被证明在很大程度上对此无效 接近。因此，虽然针对BRAFV600E和KRASG12C突变的药物显著改善了 在治疗肺癌和黑色素瘤方面，它们对结直肠癌的影响有限。 通过APC失活和其他突变，CTNNB1转录在75%的结直肠癌中上调。因为CTNNB1是 一种常见的耐药媒介，已被证明足以维持结直肠癌的增殖，我们 假设它是结直肠癌对KRAS抑制的内在抵抗的关键调节因子。尽管有多个代理 通过WNT途径靶向CTNNB1调节，到目前为止，这些已经被证明对人类使用来说毒性太大。 因此，我们使用蛋白质组学方法来定位对KRASG12C抑制的信号反应在CRC细胞系和 Kinome全基因敲除，以确定其抑制与KRASG12C抑制协同作用的激酶。通过 结合这两种方法，我们能够发现几种起信号转导作用的激酶 在KRAS和CTNNB1之间，并且其抑制与直接抑制KRAS协同减少CTNNB1 靶基因表达。由于KRASG12C抑制剂不影响正常的KRAS信号，这一令人兴奋的初步结果 数据表明，我们可能能够优先下调肿瘤中CTNNB1的表达，而不会出现全身毒性。 在这个项目中，我们将建立在这个关键的初步数据的基础上：在目标1中，我们将扩展我们对激酶的分析 KRASG12C对更多结直肠癌细胞株的抑制反应及关键激酶对其的影响 CTNNB1转录。在目标2中，我们将在患者来源的异种移植物(PDX)中使用CRISPR来绕过 验证CTNNB1在APC突变的CRC PDX中的作用的可用小分子的限制。我们将进一步 使用CRISPR或小分子(如果可用)来测试已发现的调节CTNNB1或新兴的激酶 目的1在结直肠癌治疗模型中，并确定它们在体内结直肠癌生物学中的作用。最后，在目标3中，我们将 建立具有PIK3CA突变的KRASG12C结直肠癌器官和细胞系模型，PIK3CA是一种常见的结直肠癌突变 与KRAS突变共同发生，并可能导致对KRASG12C抑制剂的耐药性，但对其有 目前没有可用的型号。这些工具将使我们能够分层分析PIK3CA突变对我们当前 治疗策略，并优化专门针对这种突变组合设计的方案。 在CRC中对KRAS驱动的信号进行了严格的研究，利用了新的小分子和强大的定量 在KRAS被抑制后，揭开KRAS和支持CRC的机制之间的联系的方法。 揭示结直肠癌对KRAS直接抑制的抗性基础将产生合理的联合策略 为转化为临床试验做好准备。