Molecular Impact of Platinum Drugs on the Proteasome and SQSTM1_P62 Complexes_A Paradigm Shift in Resistance

铂类药物对蛋白酶体和 SQSTM1_P62 复合物的分子影响_耐药范式转变

• 批准号: 10051382
• 负责人: Rajagopal Ramesh
• 金额: --
• 依托单位: OKLAHOMA CITY VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-01 至 2022-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10051382
• 关键词: 26S proteasome; Address; Alcohol consumption; Amino Acids; Antineoplastic Agents; Archives; Area; Autophagocytosis; Biological; Brain; Cancer cell line; Carboplatin; Cell Death; Cell Line; Cell Survival; Cells; Cellular Stress; Cessation of life; Chemoresistance; Cisplatin; Clinical; Complex; Diagnosis; Disease; Drug resistance; Endoplasmic Reticulum; Environmental Carcinogens; Exposure to; Failure; GTF2H1 gene; Gene Proteins; Human; In Vitro; Incidence; Innovative Therapy; Investigation; Knowledge; Laboratories; Lung Neoplasms; Malignant Neoplasms; Malignant neoplasm of lung; Military Personnel; Modeling; Molecular; Molecular Target; Nano delivery; Nature; Neoplasm Metastasis; Normal Cell; Outcome; Pathology; Patients; Pharmaceutical Preparations; Platinum; Platinum Compounds; Play; Primary Neoplasm; Proteins; Recurrence; Recurrent disease; Recycling; Reporting; Research; Resistance; Resistance development; Role; Scaffolding Protein; Services; Signal Transduction; Smoking; Specimen; Testing; Thoracic Oncology; Translational Research; Tumor Tissue; base; cancer cell; cancer stem cell; cancer therapy; chemotherapy; clinically relevant; drug development; improved; in vivo; ineffective therapies; innovation; interest; knock-down; military veteran; mortality; multicatalytic endopeptidase complex; nanoformulation; nanoparticle; novel; novel therapeutic intervention; novel therapeutics; overexpression; patient derived xenograft model; pre-clinical; prevent; protein expression; resistance mechanism; response; restoration; statistics; stem; stem cells; targeted treatment; treatment response; treatment strategy; tumor; tumor xenograft

Lung cancer-related death is primarily due to disease recurrence, drug resistance, and metastasis. Platinum compounds such as cisplatin (CDDP) and carboplatin (CBDCA) and their derivatives are widely used in the treatment of lung cancer. Although the tumors initially respond to platinum drugs, they adeptly develop resistance thereby escaping therapy. Therefore, understanding the mechanisms by which cancer cells evade therapy and develop resistance is essential for developing new therapeutic approaches for lung cancer. This application addresses a highly innovative and high-impact area of translational research that focuses on investigating how platinum-based drugs impact the proteasome and sequestosome (SQSTM1)/P62 function in cancer cells to produce drug resistance in lung cancer. Further, a nanodelivery approach targeted towards the proteasome and SQSTM1/P62 in combination with CDDP for overcoming resistance is proposed. Our interest in testing the proteasome and SQSTM1/P62 in chemoresistance stems from a serendipitous observation made in the laboratory. We observed beta 5 (β5) expression, a subunit of the large 26S proteasome complex was markedly reduced in cisplatin-resistant (CDDPR) cancer cell lines when compared to its isogenic cisplatin-sensitive (CDDPS) cell lines. β5 is the chymotryptic component of the proteasome that is required for degrading ubiquitinated proteins and recycling of amino-acids for synthesis of new proteins in the cell. Associated with reduced β5 expression in the CDDPR cells was the intracellular accumulation of proteins. Investigation into how the cellular stress induced by intracellular accumulation of proteins is overcome by the cells revealed a role for SQSTM1/P62. The primary function of SQSTM1/P62, a scaffolding protein that is activated in response to cellular stress, is to prevent cell death by aggregating intracellular accumulated polyubiquitinated proteins into aggresomes and directing towards autophagy, thereby promoting cell survival. Further, analysis for P62 expression in a subset of human lung tumor tissues showed that chemoexperienced lung tumors had higher P62 expression compared to chemonaive tumors. Although, reduced proteasome function and increased SQSTM1/P62 expression have previously been reported in cancer cells and in stem cells, the impact of chemotherapy drugs on these cellular machineries and their role in contributing to resistance has not been previously investigated and is the basis of this innovative proposal. Based on our preliminary results, we hypothesize that alterations in the proteasome and SQSTM1/p62 function in cancer cells contributes to platinum resistance. To test our hypothesis we have identified three specific aims. Aim 1. Investigate how modulating the proteasome and SQSTM1/P62 in CDDPR and CDDPS cancer cells and in normal cells alters the therapeutic response to platinum drugs in vitro. In this aim, the requirement of beta-5 subunit of the proteasome and SQSTM1/P62 to platinum sensitivity and cross-resistance to other anticancer drugs will be investigated using isogenic human cancer cell lines and compared to normal cells. Aim 2. Demonstrate restoring beta-5 subunit of the proteasome with simultaneous knock-down of SQSTM1/p62 using multifunctional nanoparticle reverts CDDPR lung tumor sensitivity to cisplatin in vivo. In this aim, we will use lung tumor xenograft and patient-derived xenograft models (PDX) to test a) whether restoration of beta-5 with simultaneous silencing of P62 in CDDPR tumors restores platinum sensitivity and b) knock-down of beta-5 with concomitant overexpression of P62 in CDDPS tumors results in platinum resistance. Aim 3. Determine the biological significance of beta-5 and SQSTM1/P62 protein expression in chemonaïve and chemotreated human lung tumor tissue specimens with clinical benefit. In this aim, archival lung tumor specimens representing primary and metastatic tumor will be examined for beta-5 and SQSTM1/P62 expression and correlate with clinical benefit.

与肺癌相关的死亡主要是由于疾病复发，耐药性和转移。铂 顺铂（CDDP）和卡铂（CBDCA）等化合物及其衍生物被广泛用于 肺癌的治疗。尽管肿瘤最初对铂药有反应，但它们熟练地发展 抗药性，从而逃脱了疗法。因此，了解癌细胞逃避的机制 治疗和发育耐药性对于开发新的肺癌治疗方法至关重要。 该应用程序涉及转化研究的高度创新和高影响力领域，重点介绍 研究基于铂的药物如何影响蛋白酶体和续集（SQSTM1）/p62功能 癌细胞在肺癌中产生耐药性。此外，针对的纳米传递方法 提出了蛋白酶体和SQSTM1/p62与CDDP结合使用以克服电阻。 我们对从偶然性的化学耐药步骤中测试蛋白酶体和SQSTM1/p62的兴趣 在实验室进行的观察。我们观察到Beta 5（β5）表达，一个大26s的亚基 相比 它的等源性顺铂敏感（CDDPS）细胞系。 β5是蛋白酶体的胰蛋白酶成分 降解泛素化蛋白和氨基酸回收的必需品，以合成新蛋白 细胞。与CDDPR细胞中β5表达降低相关的是蛋白质的细胞内积累。 研究如何通过 细胞揭示了SQSTM1/p62的作用。 SQSTM1/p62的主要功能，一种脚手架蛋白 响应细胞应激而激活的是通过聚集细胞内积累来预防细胞死亡 多泛素化的蛋白质成杂色，并导致自噬，从而促进细胞存活。 此外，在人肺肿瘤组织的一部分中p62表达的分析表明，化学症状受到化学作用 与Chemonaive肿瘤相比，肺部肿瘤的表达更高。虽然减少了蛋白酶体 以前在癌细胞和茎中已经报道了功能和SQSTM1/p62表达增加 细胞，化学疗法药物对这些细胞机的影响及其在有助于 抵抗力尚未进行过调查，并且是该创新提案的基础。 基于我们的初步结果，我们假设蛋白酶体和SQSTM1/p62功能的改变 在癌细胞中有助于铂耐药。为了检验我们的假设，我们确定了三个特定目标。 AIM 1。研究CDDPR和CDDPS癌细胞中的蛋白酶体和SQSTM1/p62的调节 在正常细胞中，会改变体外对铂药的治疗反应。 在此目标中，蛋白酶体和SQSTM1/p62的β-5亚基对铂敏感性的要求 并将使用异源性人类癌细胞系和其他抗癌药物进行交叉抗性 与正常细胞相比。 AIM 2。演示蛋白酶体的恢复β5亚基，简单地击倒 SQSTM1/p62使用多功能纳米颗粒恢复了CDDPR肺肿瘤对体内顺铂的敏感性。 在此目标中，我们将使用肺部肿瘤特征和患者衍生的定征模型（PDX）来测试a）是否是否 在CDDPR肿瘤中对p62的简单沉默来恢复β5的恢复铂敏感性和b） beta-5与CDDPS肿瘤中p62的过度表达的敲低敲除导致铂耐药性。 AIM 3。确定Chemonaï中β-5和SQSTM1/p62蛋白表达的生物学性 并具有临床益处的人类肺肿瘤组织标本。 在此目的中，将检查代表原发性肿瘤和转移性肿瘤的档案肺肿瘤标本。 Beta-5和SQSTM1/P62表达并与临床益处相关。