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: 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
• 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

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 PDAC 患者平均减少不到一年。同样，针对异常激活的小分子药物 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。这两种方法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 进展。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 单一代谢酶通常不足以将它们拒绝给癌细胞。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，大量研究表明其 对于 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 嘧啶合成酶已显示出作为抗癌药物的临床前前景。然而，这些 药物在用作单一疗法的临床试验中均未能显示出疗效 各种恶性肿瘤。对此的一个可能的解释是，细胞通过两条主要途径 产生核苷酸，称为从头途径和挽救途径，这些抑制剂阻断关键的从头途径 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。我们 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 敏感的同行。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为最强主打。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，细胞活力明显下降，嘧啶被耗尽 细胞。此外，我们有强有力的证据表明 CNX-774 正在以脱靶方式抑制 嘧啶抢救。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。