Proteasome Inhibition and ER Stress

蛋白酶体抑制和内质网应激

• 批准号: 7590692
• 负责人: David J. McConkey
• 金额: $ 25.56万
• 依托单位: UNIVERSITY OF TX MD ANDERSON CAN CTR
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-01-01 至 2013-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7590692
• 关键词: Ablation; Acetylation; Address; Affect; Animals; Apoptosis; Attenuated; Biochemical; Biological; Biological Assay; Biopsy; Bortezomib; Cancer cell line; Cell Death; Cell Line; Cells; Cellular Stress; Chemicals; Chromatin; Clinical Trials; Collaborations; Combination Drug Therapy; Combined Modality Therapy; Data; Defect; Development; Dominant-Negative Mutation; Drug Delivery Systems; Drug resistance; Drug-sensitive; Enrollment; Epithelial Cells; Exposure to; FDA approved; Gene Expression; Gene Silencing; Genes; Goals; Golgi Apparatus; Growth; HDAC6 gene; Heat-Shock Proteins 70; Heterogeneity; Histone Deacetylase; Histone Deacetylase Inhibitor; Histone deacetylase inhibition; Histones; Human; Immunohistochemistry; In Vitro; Inflammation; Laboratories; Ligands; Link; MAPK8 gene; Malignant Neoplasms; Malignant neoplasm of pancreas; Measures; Mediating; Medicine; Methods; Molecular; Molecular Profiling; Mus; Noxae; Nuclear; Nutrient; Pan Genus; Pancreas; Pathway interactions; Patients; Pattern; Peripheral Blood Mononuclear Cell; Pharmaceutical Preparations; Pharmacodynamics; Phase II Clinical Trials; Phenotype; Phosphorylation; Physiological; Play; Pre-Clinical Model; Process; Production; Proteasome Inhibition; Proteasome Inhibitor; Protein Biosynthesis; Protein Kinase; Proteins; Publishing; Relative (related person); Research; Resistance; Role; Serum; Small Interfering RNA; Solid; Stress; Structure; Techniques; Testing; Therapeutic Intervention; Toxic effect; Translations; Transmission Electron Microscopy; Treatment Protocols; Tubulin; Tumor Necrosis Factor-alpha; Tumor Necrosis Factors; Tumor-Derived; Upper arm; Vorinostat; Work; Xenograft procedure; angiogenesis; base; cancer cell; cancer therapy; carcinogenesis; cell killing; chronic pancreatitis; clinical application; cytotoxic; epithelial to mesenchymal transition; gemcitabine; human CASP4 protein; inhibitor/antagonist; interest; killings; mRNA Expression; multicatalytic endopeptidase complex; neoplastic cell; novel; peripheral blood; pre-clinical; prevent; prospective; protein expression; protein misfolding; public health relevance; research study; response; synthetic protein; therapy resistant; transcription factor; tubacin; tumor; tumor progression; tumor xenograft

DESCRIPTION (provided by applicant): Proteasome inhibitor (PI)-based combination chemotherapy is currently being evaluated for the treatment of pancreatic cancer and other solid malignancies. Our hypothesis is that PIs cause endoplasmic reticular (ER) stress in cancer cells and this stress mediates cell killing. Furthermore, we have obtained preliminary evidence that the effects of PIs on cell death are highly heterogeneous and are linked to whether or not they induce phosphorylation of eIF21, a component of the unfolded protein response (UPR) that mediates suppression of global protein synthesis. Specifically, PIs promote strong phosphorylation of eIF21 phosphorylation in the cell lines that are relatively resistant to PI-induced apoptosis, but they fail to do so (or attenuate translation) in the cell lines that are most sensitive. Identifying the biochemical basis for this heterogeneity could enable the prospective identification of tumors that are most likely to respond to PI-based combination chemotherapy and should yield new targets for therapeutic intervention. We also wish to better define the molecular mechanisms involved in the apoptosis that is induced by one of the most promising PI-based combination regimens, namely, the combination of bortezomib plus histone deacetylase (HDAC) inhibitors. We have obtained good preliminary evidence that HDAC inhibitors promote proteasome inhibitor-mediated apoptosis by disrupting cytoprotective structures known as aggresomes that appear to function to alleviate ER stress. Gene silencing studies have demonstrated that the HDAC responsible for aggresome disruption is HDAC6, and it is possible that more selective HDAC6 inhibitors will yield comparable or better tumor cell killing than pan HDAC inhibitors (like SAHA) with less toxicity. To directly test our hypotheses we propose the following Specific Aims. (1) Define the molecular mechanisms that control bortezomib-induced phosphorylation of eIF21. We will test the hypothesis that PIs inhibit PERK activation by inducing the expression of a molecular chaparone (HSP70?) that blocks PERK homoaggregation in drug-sensitive cells; (2) Determine role of ER stress in PI-induced apoptosis. Here we will assess the contributions of ROS, Ca2+, JNK, Noxa, and caspase-4 ot PI-induced apoptosis; (3): Determine the toxicity and anti-tumor efficacy of combination therapy with PIs and HDAC inhibitors in xenografts. We will compare the effects of combination therapy with PIs plus SAHA (a pan HDAC inhibitor), tubacin (HDAC6-selective), or SNDX-275 (type I HDAC-specific) in vitro and in orthotopic tumors derived from sensitive and resistant cell lines. We will also investigate whether or not pharmacodynamic markers of drug-target interaction and biological response can be measured in the peripheral blood of these animals and apply these methods to measure the effects of therapy with bortezomib plus SAHA within the context of a Phase II clinical trial in patients with pancreatic cancer. PUBLIC HEALTH RELEVANCE: Clinical trials have demonstrated that the effects of conventional and investigational cancer therapies are remarkably heterogeneous, and efforts are currently underway to match therapies to the specific molecular features associated with responsiveness to them in an effort to better exploit their effects ("personalized medicine"). The overall goal of the research proposed here is to better understand the mechanisms involved in cell killing induced by two promising classes of investigational cancer therapies (proteasome inhibitors and histone deacetylase inhibitors) so that the promising effects of these drugs that have been noted in preclinical models can be best exploited in patients. We will be directly comparing the effects of two proteasome inhibitors and three HDAC inhibitors that are either already FDA-approved, being evaluated in clinical trials, or being developed for clinical application in humans, and in our third Specific Aim we will develop and apply pharmacodynamic assays to measure drug-target interactions and the biological consequences of effective drug targeting within the context of a Phase II clinical trial in patients.

描述（由申请人提供）：目前正在评估基于蛋白酶体的抑制剂（PI）组合化疗，以治疗胰腺癌和其他固体恶性肿瘤。我们的假设是，PI在癌细胞中引起内质网（ER）应激，这种胁迫介导了细胞的杀伤。此外，我们获得了初步证据，表明PI对细胞死亡的影响高度异质，并且与它们是否诱导EIF21的磷酸化是介导抑制全球蛋白质合成的磷酸化的磷酸化。具体而言，PI促进了对PI诱导的凋亡相对抗性的细胞系中EIF21磷酸化的强磷酸化，但它们在最敏感的细胞系中未能（或减弱）。确定这种异质性的生化基础可以使肿瘤的前瞻性鉴定，这些肿瘤最有可能对基于PI的组合化疗反应，并应为治疗干预产生新的靶标。我们还希望更好地定义凋亡中涉及的分子机制，该机制是由最有希望的基于PI的组合方案之一诱导的，即Bortezomib Plus组蛋白脱乙酰基酶（HDAC）抑制剂的组合。我们获得了良好的初步证据，表明HDAC抑制剂通过破坏称为脂肪组的细胞保护结构来促进蛋白酶体抑制剂介导的凋亡，这些结构似乎可以减轻ER应激。基因沉默研究表明，负责分解干扰的HDAC是HDAC6，与PAN HDAC抑制剂（如SAHA）相比，更具选择性的HDAC6抑制剂可能会产生可比较或更好的肿瘤细胞杀伤。为了直接检验我们的假设，我们提出以下特定目标。 （1）定义控制硼替佐米诱导的EIF21磷酸化的分子机制。我们将检验以下假设，即PI通过诱导分子Chaparone（HSP70？）的表达来抑制PERK激活，从而阻止了药物敏感细胞中的PERK同型凝集。 （2）确定ER应激在PI诱导的凋亡中的作用。在这里，我们将评估ROS，Ca2+，JNK，NOXA和caspase-4 ot Pi诱导的凋亡的贡献； （3）：确定异种移植物中与PIS和HDAC抑制剂联合疗法的毒性和抗肿瘤功效。我们将在体外和从敏感和阻力细胞系中得出的原位性肿瘤中比较组合疗法与PIS Plus SAHA（PAN HDAC抑制剂），Tubacin（HDAC6选择性）或SNDX-275（I型HDAC特异性）的作用。我们还将调查是否可以在这些动物的外围血液中测量药物目标相互作用和生物反应的药效学标记物，并应用这些方法在胰腺癌患者的II期临床试验中测量bortezomib Plus SAHA治疗的影响。 公共卫生相关性：临床试验表明，常规和研究性癌症疗法的影响非常异质，目前正在努力将疗法与对其反应性相关的特定分子特征匹配，以更好地利用其影响（“个性化医学”）。这里提出的研究的总体目的是更好地了解两种有希望的研究性癌症疗法（蛋白酶体抑制剂和组蛋白脱乙酰基酶抑制剂）所诱导的细胞杀伤的机制，以便在患者中最能利用这些药物的有希望的效果。我们将直接比较两种蛋白酶体抑制剂和三种已经批准的HDAC抑制剂，在临床试验中进行了评估，或在人类的临床应用中进行评估，并且在我们的第三个具体目标中，我们将开发并应用药物学分析，以测量药物靶向相互作用和在范围内的生物学范围内的生物学影响，并在范围内进行了临床范围的II次上下文。