Targeting pyrimidine biosynthesis in pancreatic ductal adenocarcinoma

胰腺导管腺癌中靶向嘧啶生物合成

基本信息

批准号：
10316035
负责人：
Nicholas James Mullen
金额：
$ 3.66万
依托单位：
UNIVERSITY OF NEBRASKA MEDICAL CENTER
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：
2021-07-12 至 2025-07-11
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10316035
关键词：
Abraxane Address Affect Agammaglobulinaemia tyrosine kinase American Anabolism Animal Model Antineoplastic Agents Automobile Driving Biochemical Biological Assay Cancer Etiology Cell Line Cell Proliferation Cell Survival Cells Cessation of life Clinical Clinical Trials Clinical effectiveness Combined Modality Therapy DHODH gene Deoxyribonucleosides Dependence Dihydroorotate dehydrogenase Disease Down-Regulation Drug Combinations Drug Compounding Drug Targeting Drug usage Enzymes FDA approved Follow-Up Studies Genes Genetic Genetic Transcription Glucose Goals Harvest Human Hyperactivity Immune response Immune system Immunocompetent Immunocompromised Host Implant In Vitro Isotope Labeling Label Malignant Neoplasms Malignant neoplasm of pancreas Mediating Metabolic Metabolic Pathway Metabolism Monitor Mus Nucleosides Nucleotide Biosynthesis Nucleotides Nutrient Oncogenic Pancreatic Ductal Adenocarcinoma Pathway interactions Patients Pattern Pharmaceutical Preparations Pharmacotherapy Phosphotransferases Population Process Proteins Pyrimidine Pyrimidine Nucleosides Pyrimidine Nucleotides Quality of life Resistance Ribose Shock Signal Pathway Signal Transduction Site Solid Survival Rate System Testing Toxic effect Tumor Tissue Tumor-infiltrating immune cells Tyrosine Kinase Inhibitor Validation anti-cancer base cancer cell cancer type chemotherapy combat combinatorial deprivation design effective therapy efficacy evaluation efficacy testing enzyme pathway experimental group experimental study genotoxicity implantation improved in vivo inhibitor/antagonist inorganic phosphate kinase inhibitor metabolic phenotype metabolomics mouse model novel nucleotide metabolism pancreatic ductal adenocarcinoma cell pre-clinical resistance mechanism response single-cell RNA sequencing small molecule standard of care targeted treatment transcriptome sequencing transcriptomics treatment strategy tumor tumor growth tumor microenvironment tumor progression uptake

项目摘要

Project Summary Pancreatic ductal adenocarcinoma (PDAC) is almost universally lethal and is projected to become the second-leading cause of cancer related deaths in the US by 2030. Conventional (genotoxic) chemotherapy approaches that make up the current standard of care are mostly ineffective and prolong survival of advanced PDAC patients by less than one year on average. Similarly, small molecule drugs targeting aberrantly activated oncogenic signaling pathways have shown disappointing clinical results and accordingly have failed to gain FDA approval for PDAC. An alternative strategy to these two approaches is to exploit metabolic dependencies that are unique to malignant cells by virtue of their deranged cellular metabolism. While there are well-characterized resistance mechanisms to genotoxic and targeted therapies, deprivation of certain nutrients critical for proliferation of malignant cells appears to be an insurmountable barrier for cancer progression. However, cells have redundant means of acquiring these critical nutrients, and so inhibition of a single metabolic enzyme is generally not sufficient to deny them to cancer cells. Thus, combinatorial blockade of multiple metabolic pathways could be required to impose deficiency of key metabolites on malignant cells. Pyrimidine nucleotides represent a class of metabolites that has been shown in numerous studies to be essential for PDAC and a host of other malignancies. Importantly, there are several clinical grade inhibitors of pyrimidine synthesis enzymes that have shown preclinical promise as anticancer agents. However, these drugs have uniformly failed to show efficacy in clinical trials in which they were used as monotherapy against various malignancies. One potential explanation for this is that there are two major pathways by which cells generate nucleotides, termed the de novo and salvage pathways, and these inhibitors block the key de novo pathway enzyme dihydroorotate dehydrogenase (DHODH), thus leaving the salvage pathway fully intact. We’ve characterized the response of various PDAC cell lines to the DHODH inhibitor brequinar (BQ). We found that some PDAC cell lines are highly resistant to BQ in cell viability assays compared to their more sensitive counterparts. We then screened some 350 known kinase inhibitor compounds to probe for any that could restore BQ sensitivity in our resistant PDAC cell lines, and this nominated the preclinical BTK inhibitor CNX-774 as the strongest hit. Follow-up studies have shown that combined BQ/CNX-774 treatment leads to profound cell viability loss and pyrimidine depletion, compared to either drug alone, in BQ-resistant PDAC cells. Furthermore, we have strong evidence that CNX-774 is acting in an off-target manner to inhibit pyrimidine salvage. Thus, the goal of this study is to uncover the mechanism by which CNX-774 is sensitizing PDAC cells to BQ and determine if this drug combination is efficacious in our preclinical PDAC mouse models. Our goal is to provide preclinical support for this metabolic combination therapy as a potential PDAC treatment.

项目概要胰腺导管腺癌 (PDAC) 几乎是普遍致命的，预计将成为到 2030 年，将成为美国癌症相关死亡的第二大原因。传统（基因毒性）化疗构成当前护理标准的方法大多无效并且无法延长晚期患者的生存期同样，针对异常激活的小分子药物，PDAC 患者平均寿命缩短不到一年。致癌信号通路的临床结果令人失望，因此未能获得成功 FDA 批准 PDAC 的另一种策略是利用代谢依赖性。这是恶性细胞所独有的，因为它们的细胞代谢紊乱。虽然对基因毒性和靶向治疗有明确的耐药机制，但剥夺某些对恶性细胞增殖至关重要的营养素似乎是癌症不可逾越的障碍然而，细胞有多余的手段来获取这些关键营养物质，因此抑制了进展。单一代谢酶通常不足以将它们拒绝给癌细胞，因此，组合阻断。可能需要多种代谢途径来使恶性细胞缺乏关键代谢物。嘧啶核苷酸代表一类代谢物，许多研究已表明这些代谢物对于 PDAC 和许多其他恶性肿瘤至关重要，有几种临床级抑制剂。嘧啶合成酶已显示出作为抗癌药物的临床前前景。在临床试验中，它们均未能显示出药物疗效，在这些试验中，它们被用作单一疗法对此的一种可能的解释是细胞有两种主要途径。产生核苷酸，终止从头和挽救途径，这些抑制剂阻断了从头的关键途径酶二氢乳清酸脱氢酶（DHODH），从而使挽救途径保持完整。我们描述了各种 PDAC 细胞系对 DHODH 抑制剂 brequinar (BQ) 的反应。发现一些 PDAC 细胞系在细胞活力测定中对 BQ 具有高度抵抗力，与其更多的细胞系相比然后，我们筛选了大约 350 种已知的激酶抑制剂化合物，以探查是否存在任何可以恢复我们的耐药 PDAC 细胞系中的 BQ 敏感性，这指定了临床前 BTK 抑制剂 CNX-774 是最有力的打击后续研究表明 BQ/CNX-774 联合治疗可导致与单独使用任何一种药物相比，在 BQ 耐药性 PDAC 中，细胞活力大幅丧失，嘧啶被耗尽此外，我们有强有力的证据表明 CNX-774 以脱靶方式发挥抑制作用。因此，本研究的目的是揭示 CNX-774 致敏的机制。将 PDAC 细胞进行 BQ 并确定该药物组合在我们的临床前 PDAC 小鼠模型中是否有效。我们的目标是为这种代谢联合疗法作为潜在的 PDAC 治疗提供临床前支持。