Molecular Analyses of Folate and Antifolate Transport

叶酸和抗叶酸转运的分子分析

• 批准号: 8513356
• 负责人: Charles E. Dann
• 金额: $ 27.66万
• 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 2015-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8513356
• 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; 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. PUBLIC HEALTH RELEVANCE: Our proposed research program has the potential to improve public health by substantially improving the treatment of many prevalent human cancers. During chemotherapy treatment for cancer, many adverse side effects are realized by the patient due to the toxicity of the chemotherapeutic drugs in normal cells. Our work should lead to the development of novel drugs that specifically target cancer cells and therefore improve patient therapy with the added benefit of fewer side effects.

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，在临床治疗中取得了成功，但由于其对正常细胞的细胞毒性作用而受到严重限制。典型的例子是经典的抗叶酸甲氨蝶呤（MTX），它仍然以低剂量被广泛用于治疗癌症、牛皮癣和关节炎疾病。高剂量的甲氨蝶呤会导致明显的副作用，包括脱发，因为甲氨蝶呤会优先杀死快速分裂的细胞，无论正常或异常，没有区别。理想情况下，可以开发出针对病变细胞而不影响正常细胞的特异性抗叶酸药。在研究叶酸转运时，研究人员发现人类叶酸受体蛋白（hFRs）在许多肿瘤类型中过度表达，并且在炎症部位（如关节炎）激活巨噬细胞。此外，hFRs在正常组织上的表达是局部的，因此不暴露于静脉注射的药物。综上所述，设计用于hFRs的抗叶酸盐可以静脉注射，对正常组织的毒性最小。我们的建议旨在通过广泛的结构、热力学、动力学和基于细胞的hFRs与叶酸和抗叶酸配体相互作用的表征来推进新型hFRs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，实验抗叶酸和叶酸偶联药物的组织选择性递送靶点，以帮助设计治疗癌症和炎症性疾病的新药；2)阐明人类叶酸受体结合和释放配体的生物物理参数，最终描绘叶酸类药物所需的结构特征；3)分析人类叶酸受体突变体，以确定转运和释放叶酸和抗叶酸所需的FRs的关键决定因素。鉴于以叶酸为基础的药物在疾病治疗中的悠久历史，显然缺乏对hfr -配体相互作用的分子洞察力，这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，这些参数将指导下一代抗叶酸药物的合理设计，从而大大改善与癌症和慢性炎症疾病有关的公共卫生。