Isoform-specific signaling as a determinant of RAS-driven oncogenesis

同工型特异性信号传导是 RAS 驱动的肿瘤发生的决定因素

基本信息

批准号：
10559517
负责人：
Robert Kortum
金额：
$ 34.19万
依托单位：
HENRY M. JACKSON FDN FOR THE ADV MIL/MED
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：
2022-02-01 至 2027-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10559517
关键词：
Anoikis Binding Biological Assay Biological Models Cancer cell line Cell Line Cell Survival Cell physiology Cells Clinical Clustered Regularly Interspaced Short Palindromic Repeats Colon Carcinoma Cytoprotection Data Dependence Drug Synergism Feedback Genetic Models Genetically Engineered Mouse Genotype Human Impairment Individual KRAS2 gene Knock-out MEK inhibition MEKs Malignant Neoplasms Mediating Molecular Mutate Mutation Oncogenic Organoids PI3K/AKT PIK3CA gene PIK3CG gene Pathway interactions Patients Pharmaceutical Preparations Pre-Clinical Model Proliferating Protein Isoforms RAS genes RAS inhibition Ras Inhibitor Ras/Raf Reporting Research Resistance Role Signal Transduction Structure System Testing Therapeutic Therapeutic Intervention Tipifarnib Toxic effect Xenograft procedure biobank cancer cell in vivo inhibitor mutant mutational status novel novel therapeutic intervention pharmacologic preclinical trial predict responsiveness prevent ras Proteins reconstitution synergism targeted agent therapeutic target therapeutically effective therapy resistant tumor tumorigenesis

Anoikis Binding Biological Assay Biological Models Cancer cell line Cell Line Cell Survival Cell physiology Cells Clinical Clustered Regularly Interspaced Short Palindromic Repeats Colon Carcinoma Cytoprotection Data Dependence Drug Synergism Feedback Genetic Models Genetically Engineered Mouse Genotype Human Impairment Individual KRAS2 gene Knock-out MEK inhibition MEKs Malignant Neoplasms Mediating Molecular Mutate Mutation Oncogenic Organoids PI3K/AKT PIK3CA gene PIK3CG gene Pathway interactions Patients Pharmaceutical Preparations Pre-Clinical Model Proliferating Protein Isoforms RAS genes RAS inhibition Ras Inhibitor Ras/Raf Reporting Research Resistance Role Signal Transduction Structure System Testing Therapeutic Therapeutic Intervention Tipifarnib Toxic effect Xenograft procedure biobank cancer cell in vivo inhibitor mutant mutational status novel novel therapeutic intervention pharmacologic preclinical trial predict responsiveness prevent ras Proteins reconstitution synergism targeted agent therapeutic target therapeutically effective therapy resistant tumor tumorigenesis

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项目摘要

Project Summary/Abstract PI: Kortum, Robert L. Our data show that RTK−SOS1/2−WT RAS signaling is a critical therapeutic target in RAS-mutated cancers. Our objective is to differentiate between those RAS-mutated cancers in which inhibiting RTK−SOS1/2−WT RAS−effector signaling should be part of an overall effective therapeutic strategy. Direct RAS inhibition as a monotherapy is not effective long-term. RAS proteins show differential activation of RAF and PI3K pathways: HRAS potently activates PI3K but poorly activates RAF, whereas KRAS potently activates RAF but poorly activates PI3K. Because of these differences, inhibiting mutant RAS will not effectively inhibit both the RAF and PI3K pathways. Further, similar to MEK inhibition, mutant RAS inhibition relieves negative feedback controls leading to rapid hyperactivation of RTK−WT RAS signaling. A more comprehensive understanding of the interplay between mutant RAS and RTK−WT RAS signaling is essential to developing rational therapeutic approaches to treat RAS-mutated cancers. We found inhibition of RAS effectors activated poorly by mutant RAS synergizes with and limits resistance to mutant HRAS and KRAS inhibitors. The mutant HRAS inhibitor tipifarnib blocks PI3K signaling and synergizes with MEK inhibitors; covalent KRASG12C inhibitors block MEK signaling and synergize with PI3K inhibitors. We also found that the RASGEFs SOS1 and SOS2 have unique and overlapping functions that promote mutant RAS-driven transformation. SOS1 is critical for mutant RAS activation and SOS1 inhibition augments the efficacy of mutant RAS inhibitors. RTK−SOS2−PI3K signaling protects cells from anoikis and mediates mutant KRAS-driven transformation depending on the PI3K mutational status. SOS2 KO synergizes with MEK inhibitors only in PPIK3CA WT cells, whereas SRC inhibitors synergize with MEK inhibitors only in PIK3CA-mutated cells as was previously reported. These observations suggest the hypothesis that inhibiting RTK−SOS1/2−WT RAS−effector signaling will impair resistance to, and augment, current therapeutics targeting mutated RAS or downstream RAS effectors. We will test this hypothesis with the following Aims: This proposal elucidates the molecular mechanisms through which SOS1/2−WT RAS signaling drives transformation of cancers harboring specific mutant RAS isoforms. We perform studies using a combination of defined genetic model systems and more cancer-relevant systems including CRISPR-modified human cancer cell lines, xenograft studies, and studies using GEMM models to: Determine how WT RAS isoform signaling cooperates with oncogenic RAS to promote oncogenic transformation. Characterize the role of SOS1 in mutant RAS-driven proliferation and transformation, both independently and in combination with SOS2. Establish SOS2 and SRC as therapeutic targets in patient-derived colon cancer organoids based on KRAS and PIK3CA mutation status. Our findings will inform novel therapeutic approaches for eradicating subsets of RAS-mutated tumors with genotype-dependent precision.

项目摘要/摘要PI：Kortum，Robert L. 我们的数据表明，RTK-SOS1/2-WT RAS信号传导是RAS突变癌症中关键的治疗靶标。我们的目的是区分那些抑制RTK-SOS1/2-WT的RAS突变的癌症 RAS效应器信号应成为整体有效治疗策略的一部分。直接的RAS抑制作用作为单一疗法并非长期有效。 RAS蛋白显示出差异激活 RAF和PI3K途径：HRA可能会激活PI3K，但激活RAF的较差，而Kras可能会激活PI3K 激活RAF，但激活PI3K。由于这些差异，抑制突变体RA将无法有效抑制RAF和PI3K途径。此外，与MEK抑制类似，突变的RAS抑制作用负反馈控制导致RTK-WT RAS信号的快速过度激活。更全面了解突变体RAS与RTK-WT RAS信号之间的相互作用对于发展至关重要理性的治疗方法来治疗RAS突变的癌症。我们发现，突变体RAS与之协同激活的RAS效应的抑制作用较差，并限制了抗性突变的HRA和KRAS抑制剂。突变的HRAS抑制剂Tipifarnib阻断PI3K信号并协同作用与MEK抑制剂；共价krasg12c抑制剂阻止MEK信号传导并与PI3K抑制剂协同作用。我们还发现rasGEFS SOS1和SOS2具有促进突变体的独特和重叠的功能 RAS驱动的转换。 SOS1对于突变RAS激活至关重要，SOS1抑制增加了突变RAS抑制剂的功效。 RTK-SOS2-PI3K信号传导可保护细胞免受Anoikis的影响并介导突变体 KRAS驱动的转换取决于PI3K突变状态。 SOS2 KO与MEK抑制剂协同作用仅在PPIK3CA WT细胞中，而SRC抑制剂仅在PIK3CA突变细胞中与MEK抑制剂协同作用如前所述。这些观察结果表明抑制RTK-SOS1/2-WT的假设 RAS效应器信号传导将损害针对突变RAS或下游RAS效应。我们将以以下目的检验这一假设：该建议阐明了SOS1/2-WT RAS信号传导的分子机制具有特定突变Ras同工型的癌症的转化。我们使用的组合进行了研究定义的遗传模型系统和更多与癌症相关的系统，包括CRISPR修饰的人类癌使用GEMM模型的细胞系，特征研究和研究：确定WT RAS同工型信号如何与致癌Ras合作以促进致癌转化。表征sos1在突变体RAS驱动的增殖和转化，无论是独立并与SOS2结合在一起。基于患者衍生的结肠癌器官的SOS2和SRC作为治疗靶标 KRAS和PIK3CA突变状态。我们的发现将为消除新颖的治疗方法提供信息具有基因型依赖性精度的Ras突变肿瘤的子集。