Targeting pyrimidine biosynthesis in pancreatic ductal adenocarcinoma

胰腺导管腺癌中靶向嘧啶生物合成

• 批准号: 10451541
• 负责人: Nicholas James Mullen
• 金额: $ 3.74万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 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/10451541
• 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; 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

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.

项目摘要 胰腺导管腺癌（PDAC）几乎是普遍致命的，预计将成为胰腺癌的主要病因。 到2030年，它将成为美国癌症相关死亡的第二大原因。常规（遗传毒性）化疗 构成当前护理标准的方法大多无效，并且延长了晚期患者的生存期。 PDAC患者平均不到一年。类似地，针对异常激活的小分子药物， 致癌信号通路已显示出令人失望的临床结果，因此未能获得 FDA批准PDAC。这两种方法的替代策略是利用代谢依赖性 这是恶性细胞特有的，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物质的缺乏似乎是癌症不可逾越的障碍 进展然而，细胞有多余的手段来获取这些关键的营养素，因此抑制了细胞的生长。 单一代谢酶通常不足以使它们不进入癌细胞。因此，组合封锁 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，其在许多研究中已被证明是 对PDAC和许多其他恶性肿瘤至关重要。重要的是，有几种临床级抑制剂， 嘧啶合成酶已经显示出作为抗癌剂的临床前前景。但这些 在临床试验中，这些药物作为单一疗法用于治疗 各种恶性肿瘤一种可能的解释是，细胞通过两种主要途径 产生核苷酸，称为从头和补救途径，这些抑制剂阻断了关键的从头 途径酶二氢乳清酸脱氢酶（DHODH），从而使补救途径完全完整。 我们已经表征了各种PDAC细胞系对DHODH抑制剂布喹那（BQ）的反应。我们 发现一些PDAC细胞系在细胞活力测定中对BQ具有高度抗性， 敏感的对手。然后，我们筛选了大约350种已知的激酶抑制剂化合物， 可以恢复我们的耐药PDAC细胞系中的BQ敏感性，这提名了临床前BTK抑制剂 CNX-774是最强的打击。后续研究表明，BQ/CNX-774联合治疗导致 在BQ耐药PDAC中，与单独使用任一种药物相比， 细胞此外，我们有强有力的证据表明CNX-774以脱靶方式抑制 嘧啶补救因此，本研究的目的是揭示CNX-774致敏的机制 PDAC细胞与BQ结合，并确定这种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。