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

基本信息

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
项目类别：
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

项目摘要

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.

项目概要/摘要转移性结直肠癌（CRC）是美国癌症死亡的第二大原因。在前进的同时靶向治疗已经改变了许多癌症的治疗方法，但结直肠癌已被证明在很大程度上难以治愈方法。因此，虽然针对 BRAFV600E 和 KRASG12C 突变的药物显着改善了肺癌和黑色素瘤的治疗，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 CRC 中上调。由于 CTNNB1 是耐药性的常见介导物，并已被证明足以维持结直肠癌的增殖，我们假设它是 CRC 中 KRAS 抑制内在抵抗的关键介质。虽然有多个代理通过 WNT 途径靶向 CTNNB1 调节，迄今为止，这些药物已被证明对人类使用毒性太大。因此，我们使用蛋白质组学来绘制 CRC 细胞系中对 KRASG12C 抑制的信号反应，并全激酶组敲低，以确定其抑制与 KRASG12C 抑制具有协同作用的激酶。经过整合这两种方法，我们能够发现几种充当信号链接的激酶 KRAS 和 CTNNB1 之间，其抑制与直接 KRAS 抑制协同作用，从而减少 CTNNB1 目标基因表达。由于 KRASG12C 抑制剂不会影响正常的 KRAS 信号传导，这一令人兴奋的初步研究数据表明，我们或许能够优先下调肿瘤中的 CTNNB1，而不会产生全身毒性。我们将在此项目中建立这一关键的初步数据：在目标 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。在目标 2 中，我们将在患者来源的异种移植物 (PDX) 中使用 CRISPR 来规避验证 CTNNB1 在 APC 突变 CRC PDX 中的作用的可用小分子的局限性。我们将进一步使用 CRISPR 或小分子（如果可用）来测试已经发现的调节 CTNNB1 或新兴的激酶结直肠癌治疗模型中的目标 1 并确定其在体内结直肠癌生物学中的作用。最后，在目标 3 中，我们将开发具有 PIK3CA 突变的 KRASG12C CRC 类器官和细胞系模型，PIK3CA 是一种常见的 CRC 突变，与 KRAS 突变同时发生，并且可能导致对 KRASG12C 抑制剂的耐药性，但对此有目前没有可用的型号。这些工具将使我们能够分层 PIK3CA 突变对我们当前的影响治疗策略并优化专门针对这种突变组合设计的治疗方案。这项针对 CRC 中 KRAS 驱动信号传导的严格研究利用了新的小分子和强大的定量技术揭示 KRAS 与抑制 KRAS 后支持 CRC 的机制之间联系的方法。揭示结直肠癌中对直接 KRAS 抑制的耐药性基础将产生合理的组合策略准备转化为临床试验。