MIB1

恶性胶质瘤(Malignant glioma)是中枢神经系统最常见且最致命的原发性脑肿瘤。目前，胶质瘤患者的标准治疗方案仅限于手术切除和放化疗，中位生存期仅约14个月，预后极差。因此，寻找新的更有效的治疗策略和治疗靶点是胶质瘤临床治疗的迫切需求。溶瘤病毒疗法(Oncolytic Viral Therapy, OVT)是一种备受关注的新型肿瘤免疫治疗手段。溶瘤病毒(Oncolytic Virus, OVs)除了选择性感染裂解肿瘤细胞的直接溶瘤作用外，还可以介导病毒相关抗原和肿瘤新抗原的释放，最终激活机体抗肿瘤免疫实现杀伤肿瘤的效应。该疗法具有“免疫治疗”、“靶向治疗”、“基因治疗”三合一的特点，有望成为新一代抗癌利器。基于I型单纯疱疹病毒(Herpers Simplex Virus-1, HSV-1)骨架的talimogene laherparepvec(T-VEC; Imlygic)是第一款被美国FDA批准的用于治疗晚期黑色素瘤的溶瘤病毒药物。在此基础上，溶瘤单疱病毒(oHSV)已被应用于多种肿瘤，因其天然嗜神经性的特点，神经胶质瘤是其理想的肿瘤治疗模型。然而，oHSV的溶瘤活性不足及其耐药性是限制其广泛应用的主要瓶颈。揭示oHSV如何调节肿瘤微环境是阐明其耐药机制以及增强其溶瘤活性的核心所在。胶质瘤免疫微环境中浸润的免疫细胞主要为髓系细胞，中性粒细胞是其重要组分。中性粒细胞炎性死亡(NETosis)最早于2004年在细菌感染模型中被发现。后续研究发现肿瘤中NETosis发生与病人不良预后密切相关。然而，目前对于中性粒细胞炎性死亡的自身调控机制以及在肿瘤免疫治疗特别是溶瘤病毒疗法中的作用尚不清楚。m6A即RNA中腺苷酸(A)第六位N上发生的甲基化，是真核生物mRNA中丰度最高的表观转录修饰。IGF2BP3是胰岛素样生长因子-II mRNA结合蛋白(IGF2BPs, 包括IGF2BP1/2/3)家族的重要成员，是识别并结合靶RNA的m6A位点的特异性“reader”。然而，到目前为止，IGF2BP3在胶质瘤免疫微环境的作用和机制尚不清楚。2024年1月2日，复旦大学基础医学院药理学系、教育部/卫健委/医科院医学分子病毒学重点实验室、上海市病原微生物与感染前沿科学研究基地束敏峰团队，于期刊Nature Communications发表题为“Overcoming therapeutic resistance in oncolytic herpes virotherapy by targeting IGF2BP3-induced NETosis in malignant glioma”的论文，该研究揭示了溶瘤病毒耐药的关键分子机理及其干预策略。在该研究中，研究人员发现恶性胶质瘤中存在着IGF2BP3/MIB1/FTO正反馈信号轴，该轴能够激活m6A介导的CSF3释放，从而诱导NETosis，进而促进胶质瘤的生长。oHSV治疗会进一步激活IGF2BP3/MIB1/FTO轴，同时促进病毒自身复制。然而，该机制同时也诱导NETosis，最终导致治疗效果降低。通过单样本基因集富集分析，他们观察到神经胶质瘤中IGF2BP3的高丰度表达与浸润性中性粒细胞呈正相关。为了深入研究IGF2BP3对中性粒细胞功能的影响，研究人员建立了三种胶质瘤细胞与不同来源中性粒细胞的体外共培养模型。他们发现IGF2BP3以NETosis依赖的方式促进胶质瘤细胞的生长，而在PAD4-/-小鼠(NETosis缺失)的中性粒细胞中，该作用被消除。与体外实验一致，IGF2BP3过表达增强了野生型小鼠胶质瘤的生长，而在PAD4-/-小鼠中该作用显著降低，表明NETosis在IGF2BP3促进肿瘤生长中起着关键作用。为了深入探究IGF2BP3调控NETosis的机制，研究人员进行了mRNA测序分析，发现IGF2BP3/FTO以m6A依赖方式调控CSF3(中性粒细胞集落刺激因子)，同时“reader”IGF2BP3通过调控“eraser”FTO蛋白降解上调了细胞总m6A水平。通过IGF2BP3 RNA测序和FTO质谱的双组学分析，研究人员找到了E3泛素连接酶MIB1。通过后续一系列实验，研究人员发现IGF2BP3/FTO通过m6A途径调控MIB1。体外共培养实验证实了IGF2BP3/MIB1/FTO轴对NETosis的调控作用。有意思的是，研究人员发现IGF2BP3过表达富集的多条通路与病毒感染相关，其中单纯疱疹病毒感染是最富集的通路。此外，对来自oHSV感染模型的mRNA-seq数据的分析显示，NETosis形成的途径被富集，表明HSV感染与IGF2BP3诱导的NETosis之间存在潜在的关联。后续实验表明，oHSV能够对胶质瘤细胞进行杀伤作用，但会通过上调IGF2BP3诱导NETosis，影响溶瘤病毒治疗效果。因此，研究人员试图寻找一种既能够抑制IGF2BP3表达又能促进oHSV复制的药物。通过一系列药物筛选，最终发现，BET抑制剂JQ1能够显著抑制IGF2BP3诱导的NETosis，并通过将CDK9/RPB-1复合物招募到HSV基因启动子来增强病毒复制。重要的是，该小分子抑制剂被证明能透过血脑屏障，为后续临床试验打下基础(图1)。图1. 靶向抑制IGF2BP3诱导的NETosis克服恶性胶质瘤对oHSV治疗的耐药性综上，该研究揭示了RNA m6A甲基化修饰的“reader”和“eraser”之间内在调控关系，阐明了NET形成的表观机理，发现了溶瘤病毒诱导的NETosis是阻碍其溶瘤潜能的关键检查点，并提出靶向NETosis作为克服溶瘤病毒治疗耐药性的全新策略。该论文的通讯作者为束敏峰(复旦大学基础医学院)和陈菊祥(海军军医大学附属长海医院神经外科)，第一作者为复旦大学基础医学院2019级博士研究生代玮玮。注：文中插图源于 Nature Communications原文链接：https://doi.org/10.1038/s41467-023-44576-2本文仅用于学术分享，转载请注明出处。若有侵权，请联系微信：bioonSir 删除或修改！

SANTA CLARA, Calif.--(BUSINESS WIRE)-- Agilent Technologies Inc. (NYSE: A) today announced an agreement with Quest Diagnostics (NYSE: DGX), the world’s leading provider of diagnostic information services. The alliance will enable providers and patients throughout the United States to access the Agilent Resolution ctDx FIRST liquid biopsy next-generation sequencing (NGS) test. Healthcare providers can order the test beginning today. The agreement between Quest and Agilent will enable broad adoption for ctDx FIRST, a single-site premarket approved (ssPMA) test performed at the Resolution Bioscience CLIA laboratory in Kirkland, Washington. ctDx FIRST is the first liquid biopsy test approved by the U.S. Food and Drug Administration (FDA) as a companion diagnostic (CDx) to identify advanced non-small cell lung cancer (NSCLC) patients who may benefit from treatment with KRAZATI™. KRAZATI (adagrasib) received accelerated approval as a targeted treatment option for adult patients with KRASG12C-mutated locally advanced or metastatic non-small cell lung cancer (NSCLC), as determined by an FDA-approved test, who have received at least one prior systemic therapy. ctDx FIRST is also FDA-approved for tumor profiling of the epidermal growth factor receptor (EGFR) gene in accordance with professional guidelines in oncology for patients with advanced non-small cell lung cancer (NSCLC). As a professional service, the ctDx FIRST test report* includes comprehensive genomic profiling on 109 genes across four types of alterations: single nucleotide variants, indels, copy number amplifications, and fusions. “We are looking forward to the Quest Diagnostics alliance facilitating broad access to ctDx FIRST, our liquid biopsy solution,” said Paul Beresford, vice president and general manager of Agilent’s Companion Diagnostics Division. “This expands the testing options available for NSCLC patients as patients don’t always have tissue available for molecular analysis.” "The addition of the ctDx FIRST test to our oncology menu underscores our commitment to providing access to precision medicine innovations to improve care for patients with cancer," said Kristie Dolan, vice president and general manager, Oncology Franchise, at Quest Diagnostics. "It also reflects our ability to optimize our national physician and patient access network to extend access to important medical innovations with the potential to improve patient outcomes." Under the terms of the agreement, Quest will offer ctDx FIRST to healthcare providers in the United States seeking a minimally invasive liquid biopsy test option as a CDx for KRAZATI. Healthcare providers can order the test electronically through the Quest connectivity platform, which connects to hundreds of electronic medical records (EMRs). Healthcare providers may direct patients to provide specimens at one of Quest’s 2,100 patient service centers across the United States. Integrating Quest’s electronic health record (EHR) platform and access to its national patient center network will make it easier for healthcare providers to incorporate ctDx FIRST as part of regular clinical care. Agilent and Quest have previously collaborated on Ki-67 IHC MIB-1 pharmDx and PD-L1. * CLIA validated, not FDA approved About NSCLC There are two primary types of lung cancer, non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). Named initially for how the cancer cells look under the microscope, these two account for 230,000 newly diagnosed cases of lung cancer in the U.S. each year. The vast majority (85 percent) of lung cancers fall into the non-small cell lung cancer category. Though this form of lung cancer progresses more slowly than SCLC, 40 percent of NSCLCs will have spread beyond the lungs by the time it is diagnosed.i About Agilent Technologies Agilent Technologies Inc. (NYSE: A) is a global leader in the life sciences, diagnostics, and applied chemical markets, delivering insight and innovation that advance the quality of life. Agilent’s full range of solutions includes instruments, software, services, and expertise that provide trusted answers to our customers' most challenging questions. The company generated revenue of $6.85 billion in fiscal 2022 and employs 18,000 people worldwide. Information about Agilent is available at . To receive the latest Agilent news, please subscribe to the Agilent Newsroom. Follow Agilent on LinkedIn and Facebook. USE AND IMPORTANT SAFETY INFORMATION What is KRAZATI? KRAZATI is a prescription medicine used to treat adults with non-small cell lung cancer (NSCLC): that has spread to other parts of the body or cannot be removed by surgery, and whose tumor has an abnormal KRAS G12C gene, and who have received at least one prior treatment for their cancer. Your healthcare provider will perform a test to make sure that KRAZATI is right for you. It is not known if KRAZATI is safe and effective in children. IMPORTANT SAFETY INFORMATION What should I tell my healthcare provider before taking KRAZATI? Before taking KRAZATI, tell your healthcare provider about all your medical conditions, including if you: have any heart problems, including heart failure and congenital long QT syndrome, have liver problems, are pregnant or plan to become pregnant. It is not known if KRAZATI can harm your unborn baby, are breastfeeding or plan to breastfeed. It is not known if KRAZATI passes into your breastmilk. Do not breast feed during treatment and for 1 week after your last dose of KRAZATI Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. KRAZATI can affect the way other medicines work, and other medicines can affect how KRAZATI works. KRAZATI can cause serious side effects, including: Stomach and intestinal (gastrointestinal) problems. Stomach and intestinal side effects, including nausea, diarrhea, or vomiting, are common with KRAZATI but can also sometimes be severe. KRAZATI can also cause serious stomach and intestinal side effects such as bleeding, obstruction, inflammation of the colon (colitis), and narrowing (stenosis). Call your healthcare provider if you develop any of the signs or symptoms of stomach or intestinal problems listed above during treatment with KRAZATI. Your healthcare provider may prescribe an antidiarrheal medicine or anti-nausea medicine, or other treatment, as needed. Changes in the electrical activity of your heart (called QTc prolongation). Certain changes can occur in the electrical activity of your heart during treatment with KRAZATI and can be seen on a test called an electrocardiogram (ECG or EKG). QTc prolongation can increase your risk for irregular heartbeats that can be life-threatening, such as torsades de pointes, and can lead to sudden death. You should not take KRAZATI if you have congenital long QT syndrome or if you currently have QTc prolongation. See “Before taking KRAZATI, tell your healthcare provider about all of your medical conditions, including if you:” Your healthcare provider should monitor the electrical activity of your heart and the levels of body salts in your blood (electrolytes) during treatment with KRAZATI if you have heart failure, a slow heart rate, abnormal levels of electrolytes in your blood, or if you take a medicine that can prolong the QT interval of your heartbeat. Tell your healthcare provider if you feel dizzy, lightheaded, or faint, or if you get abnormal heartbeats during treatment with KRAZATI. Liver problems. Abnormal liver blood test results are common with KRAZATI and can sometimes be severe. Your healthcare provider should do blood tests before starting and during treatment with KRAZATI to check your liver function. Tell your healthcare provider right away if you develop any signs or symptoms of liver problems, including: Your skin or white part of your eyes turns yellow (jaundice), dark or “tea-colored urine,” light-colored stools (bowel movements), tiredness or weakness, nausea or vomiting, bleeding or bruising, loss of appetite, pain, aching or tenderness on the right side of your stomach area (abdomen). Lung or breathing problems. KRAZATI may cause inflammation of the lungs that can lead to death. Tell your healthcare provider or get emergency medical help right away if you have new or worsening shortness of breath, cough, or fever. The most common side effects: The most common side effects are nausea, diarrhea, vomiting, tiredness, muscle and bone pain, kidney problems, swelling, breathing trouble, decreased appetite. Certain abnormal laboratory test results are common with KRAZATI. Your healthcare provider will monitor you for abnormal laboratory tests and treat you if needed. KRAZATI may cause fertility problems in males and females, which may affect your ability to have children. Talk to your healthcare provider if this is a concern for you. These are not all the possible side effects of KRAZATI. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088. Please see KRAZATI Patient Information. i American Cancer Society. About Lung Cancer. . Accessed December 21, 2022.