Fatty acid synthase inhibitors and prostate cancer

脂肪酸合酶抑制剂与前列腺癌

基本信息

批准号：
7895851
负责人：
STEVEN J. KRIDEL
金额：
$ 24.73万
依托单位：
WAKE FOREST UNIVERSITY HEALTH SCIENCES
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-09-01 至 2011-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7895851
关键词：
Active Sites Address Affect Antineoplastic Agents Apoptosis Binding Biochemical Biological Assay Biological Availability Cell Death Cell Survival Cells Cerulenin Complex Data Development Drug Kinetics Embryo Endoplasmic Reticulum Enzymes Epithelial FDA approved Fatty Acids Fatty-acid synthase Fibroblasts Fluorescence Foundations Genetic Goals Growth Hypoxia Image In Vitro Individual Laboratories Lead Ligands Link Luciferases Malignant Neoplasms Malignant neoplasm of prostate Mediating Modeling Monitor Mus Mutation Normal Cell Palmitates Palmitoyl Coenzyme A Pathway interactions Pharmaceutical Preparations Prostatic Neoplasms Publishing Reaction Research Personnel Resistance Roentgen Rays Role Series Signal Pathway Signal Transduction Site Specificity Stress Tests Structure System Testing Thapsigargin Time Toxic effect Translating Tumor Cell Line Up-Regulation Work X-Ray Crystallography analog arm base biological adaptation to stress cancer therapy clinically relevant cytotoxic cytotoxicity design ebelactone B endoplasmic reticulum stress fatty acid biosynthesis improved in vivo inhibitor/antagonist insight killings membrane biogenesis membrane synthesis mimetics mutant neoplastic cell novel orlistat overexpression programs research study response small molecule stressor therapeutic target tumor tumor xenograft

项目摘要

DESCRIPTION (provided by applicant): Fatty acid synthase (FAS), the enzyme that synthesizes the fatty acid palmitate, is overexpressed in prostate cancer and many other cancers of epithelial origin. We have discovered that orlistat, an FDA approved drug, is a novel inhibitor of the thioesterase (TE) domain of FAS. Inhibition of FAS by orlistat results in the selective killing of tumor cells in vitro and in vivo. The goal of this project is to determine the basic cellular and biochemical mechanisms of the anti-tumor effects of orlistat and other FAS inhibitors. To this end we have demonstrated that the endoplasmic reticulum (ER) stress response is activated in tumor cells upon FAS inhibitor treatment. Activation of the ER stress response appears to be upstream of apoptosis, perhaps engaging the cell death program. Moreover, the combination of FAS inhibitors with thapsigargin, another agent known to activate ER stress, yields a synergistic decrease in tumor cell survival. We have also determined the crystal structure of the TE domain (FAS-TE) in complex with orlistat. Orlistat binds to the active site in a manner contrary to a previously proposed model of substrate binding. Three specific aims are proposed to further explore these observations and to provide a critical foundation for the design and optimization of FAS inhibitors for cancer therapy. In Specific Aim 1 we will use tumor cell lines and transformed mouse embryonic fibroblasts (MEFs) with pathway specific mutations to determine the contribution of the PERK, IRE1 and ATF6 signaling pathways to the ER stress response when FAS is inhibited. In Specific Aim 2 the ability of thapsigargin and hypoxia to enhance the cytotoxic effects of FAS inhibitors will be determined. An in vivo imaging system will also be used to monitor ER stress-driven luciferase activity in tumor xenografts of mice treated with FAS inhibitors. In Specific Aim 3 we will use X-ray crystallography to determine the structural basis for the interactions between FAS-TE and orlistat and the orlistat analog Ebelactone B. We will also test whether substrate binds in a similar manner to orlistat by determining the crystal structures of substrate and product and analyzing the activity of site-directed mutants of conserved residues within the binding groove using a new, continuous assay. These studies will provide invaluable insights into how orlistat and other FAS inhibitors initiate apoptosis and how these compounds may be useful to increase the efficacy of current cancer drugs, particularly those where resistance has occurred. The proposed crystal structures will be instrumental to the rational design of analogs of orlistat with improved target specificity, bioavailability, and pharmacokinetics for the treatment of a variety of cancers.

描述（由申请人提供）：合成脂肪酸棕榈酸酯的脂肪酸合酶（FAS）在前列腺癌和许多其他上皮起源的癌症中过表达。我们发现，FDA批准的药物Orlistat是FAS硫酯酶（TE）域的新型抑制剂。 Orlistat对FA的抑制会导致体外和体内选择性杀死肿瘤细胞。该项目的目的是确定Orlistat和其他FAS抑制剂的抗肿瘤作用的基本细胞和生化机制。为此，我们已经证明，在FAS抑制剂治疗后，在肿瘤细胞中激活内质网应力反应。 ER应力反应的激活似乎是凋亡的上游，也许与细胞死亡程序有关。此外，FAS抑制剂与Thapsigargin的组合是另一种已知激活ER应激的药物，可导致肿瘤细胞存活的协同降低。我们还确定了与Orlistat复杂的TE结构域（FAS-TE）的晶体结构。 Orlistat以与先前提出的底物结合模型相反的方式与活性位点结合。提出了三个具体目标，以进一步探索这些观察结果，并为FAS抑制剂的设计和优化提供关键的基础。在特定的目标1中，我们将使用肿瘤细胞系和带有途径特定突变的小鼠胚胎成纤维细胞（MEF）来确定PERK，IRE1和ATF6信号通路对FAS抑制FAS的贡献。在特定的目标2中，将确定Thapsigargin和缺氧增强FAS抑制剂细胞毒性作用的能力。体内成像系统还将用于监测用FAS抑制剂治疗的小鼠的肿瘤异种移植物中ER应力驱动的荧光素酶活性。在特定的目标3中，我们将使用X射线晶体学来确定Fas-Te和Orlistat以及Orlistat类似Ebelactone之间的相互作用的结构基础。我们还将测试底物是否通过与Orlistat相似的方式结合，通过确定底物和生产的晶体结构，并分析了在构造中的晶体结构，并分析了在构造中的延伸构成的持续分析，以新的结合物的结合构成了一个结合的GRO，该均具有结合累积的累及。这些研究将提供有关Orlistat和其他FAS抑制剂如何启动凋亡以及这些化合物如何有用的无价见解的见解，可用于提高当前癌症药物的疗效，尤其是那些发生抗药性的药物的功效。所提出的晶体结构将对Orlistat类似物的合理设计具有重要作用，具有提高目标特异性，生物利用度和药代动力学，以治疗多种癌症。