Molecular Analyses of Folate and Antifolate Transport

叶酸和抗叶酸转运的分子分析

• 批准号: 8706899
• 负责人: Charles E. Dann
• 金额: $ 28.62万
• 依托单位: TRUSTEES OF INDIANA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8706899
• 关键词: Address; Advanced Development; Adverse effects; Affect; Affinity; Arthritis; Binding; Biological Assay; Calorimetry; Cell Cycle Kinetics; Cell Line; Cell surface; Cells; Chemotherapy-Oncologic Procedure; Chronic; Clinical; Clinical Treatment; Complex; Cytotoxic agent; Data; Databases; Development; Discrimination; Disease; Dose; Drug Delivery Systems; Drug Design; Epithelial; Equilibrium; Fluorescence; Fluorescence Anisotropy; Folate; Folic Acid; Folic Acid Antagonists; Generations; Glycosylphosphatidylinositols; Hair; Human; Immunotherapy; In Situ; In Vitro; Inflammatory; Kinetics; Knowledge; Lead; Ligand Binding; Ligands; Malignant Neoplasms; Membrane; Methotrexate; Molecular; Mutation; Normal Cell; Normal tissue morphology; Patients; Pharmaceutical Preparations; Pharmacology; Physiological; Probability; Protein Binding; Psoriatic Arthritis; Public Health; Recording of previous events; Research; Research Personnel; Roentgen Rays; SLC19A1 gene; Site; Structural Models; Structure; Structure-Activity Relationship; Surface Plasmon Resonance; System; Therapeutic Agents; Thermodynamics; Tissues; Titrations; Toxic effect; Tumor Markers; Work; base; biophysical properties; cancer cell; cancer therapy; chemotherapy; cytotoxic; design; folate-binding protein; improved; in vivo; insight; killings; macrophage; meetings; mutant; nanoparticle; next generation; novel; overexpression; preclinical study; programs; public health relevance; receptor; research study; success; three dimensional structure; trafficking; tumor; uptake

DESCRIPTION (provided by applicant): Folate-based drugs have been employed for decades in the treatment of cancer and inflammatory disease. These drugs, commonly termed antifolates, have met with success in clinical treatments but are severely limited due to their cytotoxic effects on normal cells. A prime example is the classic antifolate methotrexate (MTX), which is still commonly used at low doses in treatment of cancer, psoriasis and arthritic disease. Higher doses of MTX lead to obvious side effects including loss of hair as MTX preferentially kills rapidly dividing cells, normal or otherwise, without discrimination. Ideally, specific antifolates that target diseased cells without affecting normal cells could be developed. In studying folate transport, researchers have discovered that human folate receptor proteins (hFRs) are overexpressed in many tumor types and also activated macrophages at the site of inflammatory conditions (e.g. arthritis). Furthermore, the expression of hFRs on normal tissue is localized such that is not exposed to drugs administered intravenously. Taken together, antifolates that are designed to be taken up specifically by hFRs could be administered intravenously with minimal toxicity to normal tissue. Our proposal seeks to advance the development of novel hFR-specific antifolate drugs through extensive structural, thermodynamic, kinetic and cell-based characterizations of the interaction of hFRs with folate and antifolate ligands. Specifically our aims are to: 1) Determine the X-ray crystallographic structures of human membrane folate receptor types 1 and 2, targets for tissue selective delivery of experimental antifolate and folate-conjugate drugs, to aid in the design of new drugs to treat cancer and inflammatory diseases; 2) Elucidate the biophysical parameters of ligand binding and release by human folate receptors to ultimately delineate the desired structural features for folate-based drugs; and 3) Analyze human folate receptor mutants to identify key determinants of FRs required for trafficking and release of folates and antifolates in situ. Given the long history of folate-based drugs in disease treatment, the obvious lack of molecular insight into hFR-ligand interaction is disappointing at best. Completion of these studies will lead to a set of molecular parameters that will guide the rational design of the next generation of antifolates, leading to profound improvements in public health relating to cancer and chronic inflammatory disease.

描述（由申请人提供）：基于叶酸的药物已用于治疗癌症和炎症性疾病数十年。这些药物通常被称为抗叶酸剂，在临床治疗中取得了成功，但由于它们对正常细胞的细胞毒性作用而受到严重限制。一个典型的例子是经典的抗叶酸甲氨蝶呤 (MTX)，它仍然常以低剂量用于治疗癌症、牛皮癣和关节炎疾病。较高剂量的 MTX 会导致明显的副作用，包括脱发，因为 MTX 会不加区别地优先杀死快速分裂的细胞，无论是正常细胞还是其他细胞。理想情况下，可以开发出针对患病细胞而不影响正常细胞的特异性抗叶酸剂。在研究叶酸转运时，研究人员发现人类叶酸受体蛋白（hFR）在许多肿瘤类型中过度表达，并且在炎症（例如关节炎）部位也激活巨噬细胞。此外，hFR在正常组织上的表达是局部的，因此不会暴露于静脉内施用的药物。总而言之，专为 hFR 吸收而设计的抗叶酸剂可以静脉注射，对正常组织的毒性最小。我们的提案旨在通过对 hFR 与叶酸和抗叶酸配体相互作用的广泛结构、热力学、动力学和基于细胞的表征来推进新型 hFR 特异性抗叶酸药物的开发。具体来说，我们的目标是： 1) 确定人膜叶酸受体 1 型和 2 型的 X 射线晶体结构，这是实验性抗叶酸和叶酸结合药物的组织选择性递送的靶点，以帮助设计治疗癌症和炎症性疾病的新药； 2) 阐明人类叶酸受体配体结合和释放的生物物理参数，最终描述叶酸药物所需的结构特征； 3) 分析人类叶酸受体突变体，以确定叶酸和抗叶酸原位运输和释放所需的 FR 的关键决定因素。鉴于叶酸类药物在疾病治疗中的悠久历史，对 hFR-配体相互作用明显缺乏分子洞察，充其量是令人失望的。这些研究的完成将产生一组分子参数，指导下一代抗叶酸药物的合理设计，从而显着改善与癌症和慢性炎症性疾病相关的公共卫生。