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: 10346971
• 负责人: John D Gordan
• 金额: $ 52.64万
• 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/10346971
• 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; 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 of activation protein; 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; 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; base; 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; 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。虽然进步 在有针对性的疗法中，已改变了许多癌症的治疗方法，CRC已被证明在很大程度上难治性 方法。因此，尽管针对BRAFV600E和KRASG12C突变的试剂显着改善了 肺癌和黑色素瘤的治疗仅显示在CRC中的影响有限。 CTNNB1转录通过APC失活和其他突变在> 75％的CRC中上调。如CTNNB1 一种常见的耐药性介质，已被证明足以维持CRC增殖，我们 假设它是CRC中对KRAS抑制的内在耐药性的关键介体。虽然多个代理 通过WNT途径进行靶标CTNNB1调节，这些调节被证明对人类使用过的毒性过于毒性。 因此，我们已经使用蛋白质组学来绘制CRC细胞系中KRASG12C抑制的信号响应，并绘制 整个Kinome的敲低识别激酶，其抑制与KRASG12C抑制协同作用。经过 整合了这两种方法，我们能够发现几种充当信号链接的激酶 在KRAS和CTNNB1之间，其抑制作用与直接KRAS抑制协同以减少CTNNB1 靶基因表达。由于KRASG12C抑制剂不会影响正常的KRAS信号，因此这种令人兴奋的初步 数据表明，我们可能能够优先将CTNNB1下调而没有全身毒性。 我们将基于此项目的关键初步数据：在AIM 1中，我们将扩展对激酶的分析 对KRASG12C抑制对其他CRC细胞系的反应，并评估关键激酶对 CTNNB1转录。在AIM 2中，我们将在患者衍生的异种移植物（PDX）中使用CRISPR来规避 可用的小分子的局限性以验证CTNNB1在APC突变型CRC PDX中的作用。我们将进一步 使用CRISPR或小分子（如果可用）来测试已经发现调节CTNNB1或出现的激酶 来自CRC治疗模型中的AIM 1，并确定其在体内CRC生物学中的作用。最后，在目标3中，我们将 在PIK3CA中开发具有突变的Krasg12c CRC类器官和细胞系模型，这是一个常见的CRC突变，该突变是 与KRAS突变的共同存在，可能会引起Krasg12c抑制剂的耐药性，但其中有 当前没有可用的模型。这些工具将使我们能够对PIK3CA突变对当前的影响进行分层 治疗策略并优化专门针对这种突变组合的治疗方案。 对CRC中KRAS驱动的信号传导的严格研究利用了新的小分子和鲁棒的定量 揭露KRAS与支持KRAS抑制后CRC的机制之间的联系的方法。 揭示CRC中对直接KRAS抑制的阻力的基础，将产生合理的组合策略 用于翻译成临床试验。