Targeting cholesterol metabolism and replication stress response in cancer therapy

癌症治疗中针对胆固醇代谢和复制应激反应

基本信息

批准号：
10328961
负责人：
Junran Zhang
金额：
$ 34.97万
依托单位：
OHIO STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-02-01 至 2026-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10328961
关键词：
ATM function ATR checkpoint Address Affect Antifungal Agents Biological Biological Assay CHEK1 gene CRISPR/Cas technology Ca(2+)-Calmodulin Dependent Protein Kinase Cancer Etiology Cancer Patient Cell Death Cell Line Cell Survival Cells Cessation of life Cholesterol Cholesterol Homeostasis Clinical Clinical Trials Complex Cytogenetics DNA DNA Damage DNA Repair DNA Repair Disorder DNA biosynthesis DNA replication fork Data Defect Disease Drug Targeting Endoplasmic Reticulum Enzymes Event FDA approved Fiber Fura-2 Goals Human Immunotherapy Impairment In Vitro Interruption Lead Malignant Neoplasms Malignant neoplasm of lung Mediating Movement Non-Small-Cell Lung Carcinoma Oncogenic Pathway interactions Pharmacology Phosphoric Monoester Hydrolases Phosphotransferases Prognosis Proteins Reporter Reporting Role Signal Transduction Squalene Techniques Testing Woman anticancer research antitumor effect ataxia telangiectasia mutated protein base biological adaptation to stress cancer cell cancer diagnosis cancer therapy cell growth cholesterol biosynthesis cholesterol control endoplasmic reticulum stress epoxidase genome-wide homologous recombination improved in vitro Assay inhibitor innovation knock-down live cell imaging loss of function lung cancer cell men mouse model multimodality neoplastic cell novel novel strategies novel therapeutic intervention overexpression patient derived xenograft model prevent protein expression ratiometric repaired replication stress response screening small hairpin RNA targeted treatment therapy resistant treatment strategy tumor growth

项目摘要

Project Summary: Lung cancer is the leading cause of cancer deaths in both men and women. Non-small cell lung cancer (NSCLC) accounts for large majority of lung cancer diagnoses, and novel treatment strategies for this disease are urgently needed. ATR and its downstream effector CHK1 are key component of replication stress (RS) response that specifically deal with the stalled replication forks during DNA replication and are critical for cell survival under RS. Inhibitors targeting ATR and CHK1 are currently being tested in clinical trials. However, only limited efficacy has been observed when those agents are combined with standard therapy. Identifying the new synergistic conditions that render cells sensitive to ATR/CHK1 inhibitors will be key to improving the efficacy of these agents. Squalene epoxidase (SQLE), an enzyme controlling cholesterol biosynthesis by converting squalene to oxidosqualene in endoplasmic reticulum (ER), is frequently overexpressed in human cancers, including lung cancer. High expression of SQLE is associated with poor prognosis. Our recent genome-wide loss of function screen discovered that SQLE reduction led to enhanced sensitivity to a CHK1 inhibitor. Thus, the goal of this application is to determine whether SQLE inhibition sensitizes NSCLC cells to ATR and CHK1 inhibitors and whether high SQLE-expressing NSCLC cancer can be specifically targeted by the combined inhibition of SQLE and ATR/CHK1. Our preliminary data suggest that SQLE inhibition by shRNA knockdown causes RS and activates ATR/CHK1 activation. In addition, SQLE inhibition lead to increased protein expression of WIP1, a phosphatase that suppress the activity of ATM, a master DNA damage response protein controlling DNA repair. We hypothesize that SQLE inhibition leads to increased RS by suppressing DNA repair, rendering cells sensitive to ATR and CHK1 inhibition. Thus, co-administration of an SQLE inhibitor and an ATR or CHK1 inhibitor could synergistically suppress tumor growth. To test our hypothesis, three Specific Aims are proposed. Specific Aim 1 will interrogate the mechanism by which SQLE inhibition leads to increased WIP1 expression. Specific Aim 2 will determine whether SQLE inhibition leads to increased RS by impairing DNA repair, particularly homologous recombination, a major repair pathway that prevents and antagonizes RS. Specific Aim 3 will assess the efficacy of combined SQLE inhibition and ATR/CHK1 inhibition in suppressing tumor cell growth using in vitro assays as well as cell line-based and patient-derived xenograft (PDX) models of NSCLC. If successful, our studies will reveal a new synthetic lethal interaction between inhibition of SQLE and ATR/CHK1 and will have a significant impact on improving the survival of lung cancer patients by identifying novel therapeutic approaches.

项目摘要：肺癌是男性和女性癌症死亡的主要原因。非小细胞肺癌（NSCLC）大部分肺癌的诊断占绝大多数，而这种疾病的新型治疗策略却是需要。 ATR及其下游效应子CHK1是复制应力（RS）响应的关键组成部分，在DNA复制过程中特别处理停滞的复制叉，对于细胞存活至关重要卢比。目前，针对ATR和CHK1的抑制剂正在临床试验中进行测试。但是，只有有限的功效当这些药物与标准疗法结合使用时，已经观察到。确定新的协同作用使细胞对ATR/CHK1抑制剂敏感的细胞的条件对于提高这些药物的功效至关重要。沙丘环氧化酶（SQLE），一种通过将矛烯转化为胆固醇生物合成的酶内质网（ER）中的氧化喹啉烯在包括肺在内的人类癌中经常过表达癌症。 SQLE的高表达与预后不良有关。我们最近全基因组功能丧失屏幕发现SQLE还原导致对CHK1抑制剂的敏感性增强。因此，目标的目标应用是确定SQLE抑制是否使NSCLC细胞对ATR和CHK1抑制剂以及是否可以通过SQLE的联合抑制来专门针对表达高平方的NSCLC癌和ATR/CHK1。我们的初步数据表明，shRNA敲低的SQLE抑制会导致Rs和激活ATR/CHK1激活。另外，SQLE抑制导致WIP1的蛋白表达增加抑制ATM活性的磷酸酶，ATM的活性，一种控制DNA修复的主DNA损伤反应蛋白。我们假设SQLE抑制通过抑制DNA修复，从而导致RS增加，从而使细胞敏感到ATR和CHK1抑制作用。因此，平方英尺抑制剂和ATR或CHK1抑制剂的共同给药可以协同抑制肿瘤生长。为了检验我们的假设，提出了三个具体目标。具体目标1 将询问SQLE抑制导致WIP1表达增加的机制。具体目标2将确定SQLE抑制是否通过损害DNA修复会导致RS增加，尤其是同源重组是一种可防止和拮抗Rs的主要修复途径。特定目标3将评估功效使用体外测定AS抑制肿瘤细胞生长的联合SQLE抑制和ATR/CHK1抑制以及NSCLC的基于细胞系和患者衍生的异种移植（PDX）模型。如果成功，我们的学习将揭示了SQLE和ATR/CHK1抑制之间的新合成致命相互作用，并且具有显着的通过鉴定新的治疗方法来改善肺癌患者的存活情况。