权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

A Fragment-Based Strategy for K-RAS Covalent Inhibitors

基于片段的 K-RAS 共价抑制剂策略

基本信息

批准号：
10443837
负责人：
Samy Meroueh
金额：
$ 45.98万
依托单位：
INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-07-02 至 2025-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10443837
关键词：
Affinity Amino Acids Binding Binding Sites Biochemical Biological Biological Assay Cancer cell line Cell Proliferation Cell Survival Cells Cellular biology Clinical Trials Codon Nucleotides Collection Colon Carcinoma Colorectal Colorectal Cancer Communities Computing Methodologies Crystallization Cysteine Data Development Event Fluorescence Fluorides GTP Binding Goals Guanine Guanine Nucleotide Exchange Factors Guanosine Triphosphate Phosphohydrolases KRAS2 gene Lead Libraries Ligands Lung Adenocarcinoma Lysine Malignant Neoplasms Malignant neoplasm of lung Mass Spectrum Analysis Methods Mission Mutate Mutation Non-Small-Cell Lung Carcinoma Nucleotides Oncogenes Pancreatic Ductal Adenocarcinoma Pharmaceutical Preparations Phosphorylation Positioning Attribute Proteins Public Health RAS inhibition Ras Inhibitor Reaction Reporting Resolution Roentgen Rays Serine Signal Transduction Site Solubility Son Structure Testing Therapeutic Therapeutic Agents Threonine Time Tyrosine United States National Institutes of Health Western Blotting Work X-Ray Crystallography adduct antagonist base cancer cell cheminformatics covalent bond design experience inhibitor lead optimization liquid chromatography mass spectrometry mortality mutant non-oncogenic novel pancreatic cancer patients pancreatic ductal adenocarcinoma cell reaction rate screening small molecule small molecule inhibitor structural biology therapeutic development three dimensional structure tumor tumor growth

项目摘要

ABSTRACT KRAS is the most frequently mutated oncogene with mutation rates of 95% in pancreatic ductal adenocarcinoma (PDAC), 45% in colorectal cancer, and 30% in lung adenocarcinomas. The most common K-RAS mutations occur at codon 12, namely G12D, G12V, G12C, and G12R. K-RAS was considered undruggable due to lack of well-defined drug-binding pockets. But a recent breakthrough was achieved with covalent inhibitors that form a bond with K-RAS G12C cysteine. Several of these compounds are in clinical trials, and one was given FastTrack status by the FDA. Unfortunately, only a small fraction of K-RAS oncogene mutants harbor the G12C mutation, and G12D, G12V and other mutations do not provide an accessible cysteine nucleophile. In recent work with the RAS GTPase Ral we showed through high-resolution structures and extensive biochemical studies that covalent bond formation with Tyr-82 created a well-defined novel binding site located between the Switch II and the Switch I/II pockets. Additional fragment screening carried out more recently identified a fragment that forms a covalent bond at K-RAS Switch II Tyr-64 to inhibit activation of the GTPase by the Son-of-Sevenless (SOS) guanine exchange factor. Here, we hypothesize that covalent bond formation with tyrosine or other amino acids on K- RAS will inhibit activation or effector binding and block K-RAS signaling in cancer cells. Our preliminary data and extensive experience in the field puts us in a strong position to accomplish our objectives. In Specific Aim 1, we employ ligand- and structure-based methods to generate fragment electrophile libraries from large commercial collections, and we follow a structure-based method to grow hit fragments into neighboring pockets to enhance their binding affinity and reaction rates. In Specific Aim 2, we will carry out well-established intact protein mass spectrometry, nucleotide exchange, and effector binding studies to screen fragment libraries for hit compounds, and to characterize small molecules that emerge from fragment growing strategies. In Specific Aim 3, we will use X-ray crystallography to solve the structure of hit fragments and derivatives that emerge from fragment growing efforts. We also carry out cell biological studies to confirm direct engagement of K-RAS, inhibition of K- RAS signaling, and inhibition of cancer cell proliferation. We expect to identify high quality fragments and small molecules that form a covalent bond at wild-type and mutant K-RAS oncogenes, inhibit K-RAS wild-type or oncogene mutant activity in cancer cell lines, and inhibit PDAC and lung adenocarcinoma cancer cell viability. These compounds will serve as starting points to pursue in lead optimization efforts towards the development of therapeutic agents for the treatment of K-RAS-driven tumors.

摘要