Regulation of EGFR by SC4MOL- and NSDHL-Dependent Trafficking

SC4MOL 和 NSDHL 依赖性贩运对 EGFR 的调节

基本信息

批准号：
8537870
负责人：
Igor Astsaturov
金额：
$ 21.9万
依托单位：
RESEARCH INST OF FOX CHASE CAN CTR
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-09-01 至 2014-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8537870
关键词：
Antineoplastic Agents Bioinformatics Biological Biological Markers Biological Testing Candidate Disease Gene Cell Survival Cell membrane Cetuximab Development Dimerization Drug Targeting Drug resistance Engineering Enzymes Epidermal Growth Factor Receptor Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor Epithelial Cells Erlotinib Eukaryota Excision Future Genes Goals Growth Ligands Link Literature Lysosomes Malignant Neoplasms Metabolic Metabolism Methods Modeling NADP Oncogenes Orthologous Gene Oxidases Oxidoreductase Pharmaceutical Preparations Phenotype Positioning Attribute Process Proteins RNA Interference Receptor Signaling Regulation Resistance Role Science Selection for Treatments Signal Transduction Small Interfering RNA Steroids Sterol Biosynthesis Pathway Sterols System Systems Biology Testing Therapeutic Therapeutic Agents Ubiquitination Work base cancer cell cancer prevention cancer therapy cell growth desensitization drug development enzyme pathway genetic analysis in vivo insight neoplastic cell network models promoter protein degradation protein transport public health relevance receptor expression resistance mechanism response screening small hairpin RNA therapeutic target tool trafficking

项目摘要

DESCRIPTION (provided by applicant): Our goal is to integrate systems biology approaches into the analysis of cancer drug resistance mechanisms, and thus to develop and evaluate new strategies for the efficient selection of optimal therapeutic combinations. In our recent work, we used siRNA screening to interrogate over 600 candidate genes from a set we nominated by network modeling to be enriched for regulators of EGFR signaling. This and subsequent analysis identified SC4MOL (sterol C4-methyl oxidase-like), a little-studied intermediate in the sterol biosynthesis pathway, as a potent regulator of cell viability following treatment with the EGFR inhibitors erlotinib and cetuximab. To understand the mechanism of SC4MOL action, we again used a bioinformatics strategy to model an interaction network for evolutionarily conserved orthologs of SC4MOL and its partner protein, NSDHL (NADP-dependent steroid dehydrogenase-like). This predicted multiple connections to regulators of exocytic trafficking and protein degradation. In direct preliminary test of the network predictions, we demonstrated that RNAi depletion of SC4MOL or NSDHL resulted in loss of EGFR from the plasma membrane, and enhanced its ubiquitination and degradation. Our hypothesis is that loss of interactions between SC4MOL and NSDHL with partner proteins influences trafficking so as to accelerate EGFR degradation, thereby potentiating EGFR-targeting drugs. To further validate this approach to identifying modifiers of targeted response, and potentially validate SC4MOL and NSDHL as biomarkers of drug response and/or targets for drug development, we will perform the following two Aims: Aim 1. Investigate the mechanism by which SC4MOL and NSDHL regulate EGFR trafficking. We will assess how SC4MOL and NSDHL influence EGFR trafficking and degradation, and whether the catalytic activity of SC4MOL and NSDHL is required for their actions. We will analyze interactions between SC4MOL and a small set of predicted conserved interaction partners with known roles in regulating vesicular trafficking predicted by bioinformatics analysis of the orthologs in lower eukaryotes. Aim 2. Investigate the interaction of SC4MOL and NSDHL with ERAD proteins. We have found silencing of SC4MOL or NSDHL enhances EGFR ubiquitination and lysosomal degradation. Our analysis identified a number of candidates within the ER-associated protein degradation (ERAD) system, which will be tested for physical association with SC4MOL and NSDHL, and for a role in SC4MOL- and NSDHL-dependent regulation of EGFR expression, trafficking, and degradation. Given the prominence of EGFR as a target in cancer therapy, this work has potentially high impact to reduce drug resistance relevant to many clinically valuable therapeutic agents.

描述（由申请人提供）：我们的目标是将系统生物学方法整合到癌症耐药机制的分析中，从而开发和评估有效选择最佳治疗组合的新策略。在我们最近的工作中，我们使用 siRNA 筛选来询问我们通过网络模型指定的一组候选基因，以丰富 EGFR 信号传导的调节因子。这项分析和随后的分析确定了 SC4MOL（甾醇 C4 甲基氧化酶样），一种很少被研究的甾醇生物合成途径中间体，是 EGFR 抑制剂厄洛替尼和西妥昔单抗治疗后细胞活力的有效调节剂。为了了解 SC4MOL 的作用机制，我们再次使用生物信息学策略来模拟 SC4MOL 及其伴侣蛋白 NSDHL（NADP 依赖性类固醇脱氢酶样）的进化保守直向同源物的相互作用网络。这预测了与胞吐运输和蛋白质降解调节因子的多重联系。在网络预测的直接初步测试中，我们证明 SC4MOL 或 NSDHL 的 RNAi 耗竭导致 EGFR 从质膜上丢失，并增强了其泛素化和降解。我们的假设是，SC4MOL 和 NSDHL 与伙伴蛋白之间相互作用的丧失会影响运输，从而加速 EGFR 降解，从而增强 EGFR 靶向药物的作用。为了进一步验证这种方法来识别靶向反应的修饰剂，并潜在地验证 SC4MOL 和 NSDHL 作为药物反应的生物标志物和/或药物开发的目标，我们将实现以下两个目标：目标 1. 研究 SC4MOL 和 NSDHL 调节 EGFR 运输的机制。我们将评估 SC4MOL 和 NSDHL 如何影响 EGFR 运输和降解，以及它们的作用是否需要 SC4MOL 和 NSDHL 的催化活性。我们将分析 SC4MOL 与一小组预测的保守相互作用伙伴之间的相互作用，这些相互作用伙伴在调节囊泡运输方面具有已知的作用，这些作用是通过对低等真核生物中的直系同源物的生物信息学分析预测的。目标 2. 研究 SC4MOL 和 NSDHL 与 ERAD 蛋白的相互作用。我们发现 SC4MOL 或 NSDHL 的沉默会增强 EGFR 泛素化和溶酶体降解。我们的分析确定了 ER 相关蛋白降解 (ERAD) 系统内的许多候选者，将测试其与 SC4MOL 和 NSDHL 的物理关联，以及在 SC4MOL 和 NSDHL 依赖性 EGFR 表达、运输和代谢调节中的作用。降解。鉴于 EGFR 作为癌症治疗靶点的重要性，这项工作对于减少与许多具有临床价值的治疗药物相关的耐药性具有潜在的巨大影响。