Targeting GRP78 for p53 activation as anti-cancer therapy

靶向 GRP78 激活 p53 作为抗癌疗法

基本信息

批准号：
9008031
负责人：
Hua Lu
金额：
$ 16.37万
依托单位：
TULANE UNIVERSITY OF LOUISIANA
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-03-01 至 2018-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9008031
关键词：
Address Affinity Chromatography Antineoplastic Agents Apoptosis Apoptotic Area Binding Biochemical Biological Assay Biotin Bortezomib Cancer Cell Growth Cancer Model Cell Cycle Arrest Cell Nucleus Cell Survival Cell surface Cells Clinic Colon Combined Modality Therapy Coupled DNA Repair Deacetylase Defect Development Disease Endoplasmic Reticulum Flow Cytometry Fluorescence Microscopy Future GRP78 gene Genome Stability Goals Growth Health Homeostasis Human In Vitro Investigation Investments Label Lung Maintenance Malignant Neoplasms Malignant neoplasm of lung Mass Spectrum Analysis Measures Mediating Molecular Chaperones Mutation Names Nelfinavir Neoplasm Metastasis Normal Cell Nuclear Translocation Pathway interactions Pharmacologic Substance Play Prevention Process Production Protein p53 Proteins Quality Control Role Signal Transduction Stress TP53 gene Testing Transcriptional Activation Tumor Angiogenesis Tumor Suppression Tumor Suppressor Proteins Xenograft procedure anticancer activity anticancer research biophysical techniques cancer cell cancer therapy celecoxib drug discovery endoplasmic reticulum stress glucose-regulated proteins improved insight mortality mouse model neoplastic cell novel p53 Signaling Pathway protein folding research and development response senescence small molecule therapy development therapy resistant tool tumor tumor growth tumor progression uptake

项目摘要

DESCRIPTION (provided by applicant): Despite numerous major scientific breakthroughs and tremendous R&D investments in the pharmaceutical sector over the past 3 decades, cancer still is the leading cause of disease-related mortality and awaits further advances toward improved therapy. Intensive effort has been focusing on the tumor suppressor p53 pathway because nearly all cancers show defects in this pathway, over 50% of which have mutations in the TP53 gene itself. We recently discovered Inauhzin (INZ) as a novel non-genotoxic p53 activator. INZ activates p53 by targeting SIRT1 and consequently suppresses tumor growth. In our ongoing studies to explore other possible targets of this compound, we identified a 78-kDa glucose-regulated protein (GRP78, also called BiP) as one of the top INZ target candidates. GRP78 is traditionally regarded as a major endoplasmic reticulum (ER) chaperone and a master regulator of the unfolded protein response (UPR) facilitating protein folding and assembly, protein quality control and regulating ER stress (ERS) signaling. Recent advances using mouse models and cellular approaches have revealed that GRP78 also functions beyond the ER. This discovery is not only critical for better understanding the unique and essential role of GRP78 in cancer development and prevention, but also offers an opportunity for cancer-specific targeting. Interestingly and surprisingly, we have also found that INZ can trigger the nuclear translocation of GRP78 that co-localized with accumulated p53 in the nucleus of cancer cells. Our finding suggests that INZ may regulate GRP78 through mechanisms distinct from the ERS-UPR pathway. Hence, the objectives of this application are to validate GRP78 as another bona fide target of INZ and to elucidate the mechanism underlying the role of GRP78 in INZ-induced p53 activation and anticancer activities. Our central hypothesis is that GRP78 is the direct tumor-specific target for INZ, leading to ER-independent activation of the p53 signaling pathway in cancer, but not normal, cells, and the combination of clinically used ERS/UPR-associated modulators with the p53 activator INZ may be a successful approach for overcoming chemoresistance and eliminating tumors. We will test this hypothesis by addressing the following Specific Aims: (1) to biochemically and biophysically characterize the specific binding of INZ to GRP78 in vitro and in cells; (2) to determine the role of cell-surface GRP78 in INZ uptake and specific cancer targeting, to determine how GRP78 is imported from ER to the nucleus by INZ to mediate p53 activation, and to evaluate the synergistic effect of INZ with clinically used ERS/UPR-associated modulators. Should our exploratory studies demonstrate GRP78 as a cancer specific target for INZ through an ER-independent p53 activation, this would not only provide proof-of-concept evidence for targeting both of the ER Stress/UPR related and p53 signaling pathways for cancer therapy, but would also offer new insights into the role of GRP78 in cancer development and therapy and have a strong impact on the area of molecule-specific anti- cancer drug discovery, particularly in the field of translational cancer research.

描述（由申请人提供）：尽管在过去30年中，在药品部门进行了许多重大的科学突破和巨大的研发投资，但癌症仍然是与疾病相关的死亡率的主要原因，并且正在等待改善治疗的进一步进步。密集的努力一直集中在肿瘤抑制p53途径上，因为几乎所有癌症都在该途径中显示出缺陷，其中50％以上的TP53基因本身具有突变。我们最近发现了Inauhzin（INZ）是一种新型的非生物毒性p53激活剂。 INZ通过靶向SIRT1激活p53并因此抑制肿瘤生长。在我们正在进行的探索该化合物的其他可能靶标的研究中，我们确定了一种78 kDa葡萄糖调节的蛋白（GRP78，也称为BIP）是顶级INZ目标候选者之一。传统上，GRP78被视为主要的内质网（ER）伴侣，也是展开的蛋白质反应（UPR）的主要调节剂，促进蛋白质折叠和组装，蛋白质质量控制和调节ER应激（ERS）信号传导。使用小鼠模型和细胞方法的最新进展表明，GRP78在ER之外还起作用。这一发现不仅对于更好地了解GRP78在癌症发展和预防中的独特和重要作用至关重要，而且还为特定于癌症的靶向提供了机会。有趣的是，令人惊讶的是，我们还发现INZ可以触发与癌细胞核中累积p53共定位的GRP78的核转运。我们的发现表明，INZ可以通过不同于ERS-UPR途径的机制来调节GRP78。因此，本应用的目标是将GRP78验证为INZ的另一个真正的目标，并阐明GRP78在INZ诱导的p53激活和抗癌活性中的作用的机制。我们的中心假设是GRP78是INZ的直接肿瘤特异性靶标，导致癌症中p53信号传导途径的激活，但不是正常的，细胞，并且与临床/UPR相关的调节剂的组合使用p53激活剂与p53激活剂的临床相关调节剂与p53激活剂INZ可能是成功的化学和消除化学物质的成功方法。我们将通过解决以下特定目的来检验这一假设：（1）生物化学和生物物理上表征INZ在体外和细胞中与GRP78的特异性结合；（2）确定细胞表面GRP78在INZ摄取和特定癌症靶向中的作用，以确定如何通过INZ从ER到核进口GRP78以介导p53激活，并评估INZ与临床使用的ERS/UPR/UPR相关的调节剂的协同作用。如果我们的探索性研究通过与ER无关的p53激活证明了GRP78是INZ的癌症特定靶标，那么这不仅将提供概念概念的证据，用于针对癌症治疗的ER压力/UPR相关和p53信号传导途径，而且还将为GRP78在癌症开发和癌症中的作用提供新的见解，并为癌症的影响提供了新的见解，并将其尤其为癌症的影响提供了分数，这是分数的强大影响，并将其与癌症的影响相关。转化癌研究。