PDCD4

Protein arginine methyltransferases (PRMTs) are catalytic enzymes for arginine methylation, capable of methylating a variety of proteins and playing pivotal roles in biological processes such as gene expression, splicing, and DNA damage repair.  Currently, 9 members of the PRMTs family has been identified, divided into three major types. Type I, catalyzes the formation of asymmetric dimethylarginine and includes PRMT1, PRMT2, PRMT3, PRMT4, PRMT6, PRMT8. Type II catalyzes the formation of symmetric dimethylarginine and includes PRMT5 and PRMT9. Type III is responsible for the formation of monomethylarginine and includes only PRMT7.  PRMT5 is the most highly studied subtype of PRMT, forming a heterooctameric complex with Methylosome protein 50 (MEP50), enabling the symmetrical dimethylation of a variety of substrates, including histone and non-histone proteins. PRMT5 histone substrates primarily include H4 residue Arg3 (H4R3), H3 residue Arg2 (H3R2), Arg8 (H3R8), and H2A residue Arg3 (H2AR3), whose symmetric dimethylation is related to gene transcription regulation. Non-histone substrates of PRMT5 include Sm proteins, nucleolar proteins, RAF proteins, EGFR, androgen receptor (AR), tumor suppressor p53, IL-2, HOXA9, NFkB, KLF4, GATA4, PDCD4, E2F-1, SPT5, GM130, POLR2A, SREBP1a, Rad9, and more that are involved in regulating cellular signalling, differentiation, DNA repair, and mRNA splicing among other cellular processes.  Research has found that PRMT5 is overexpressed in various types of cancer, such as glioblastoma, melanoma, leukemia/lymphoma, multiple myeloma, prostate cancer, bladder urothelial carcinoma, ovarian cancer, lung cancer, gastric cancer, and colorectal cancer. Furthermore, PRMT5 expression is associated with a poor prognosis in tumor progression and metastasis. Further research has shown that PRMT5 directly affects the growth and differentiation of tumor cells by regulating multiple genes such as p53, IL-2, TRAIL receptor, MITF, transcription factor E2F-1, and tumor suppressor gene 7. Additionally, PRMT5 has been found to constitute "synthetic lethal" partnerships with gene mutations like methylthioadenosine phosphorylase (MTAP), metabolic enzyme methionine adenosyltransferase 2 alpha (MAT2A), and others.  Both in vitro and in vivo studies have shown that inhibition or knockdown of PRMT5 significantly reduces cell proliferation, migration, and colony formation, but promotes apoptosis and cell cycle arrest. Furthermore, oral PRMT5 inhibitors demonstrate significant antitumor activity in lung tumor xenograft models. Thus, PRMT5 has become a new target for the development of epigenetic anti-cancer drugs. PRMT5 Competitive LandscapeAccording to the data provided by Patsnap Synapse-Global Drug Intelligence Database: the following figure shows that as of 22 Sep 2023, there are a total of 41 PRMT5 drugs worldwide, from 39 organizations, covering 28 indications, and conducting 20 clinical trials. 👇Please click on the picture link below for free registration or login directly if you have freemium accounts, you can browse the latest research progress on drugs , indications, organizations, clinical trials, clinical results, and drug patents related to this target. Based on the analysis of target PRMT5, it can be concluded that several companies, including GSK Plc, Ipsen SA, Tango Therapeutics, Inc., Amgen, Inc., Mirati Therapeutics, Inc., and Prelude Therapeutics, Inc., are actively involved in the research and development of drugs targeting PRMT5. These companies have drugs in various stages of development, with some reaching advanced stages such as Phase 2. The indications for these drugs cover a wide range of cancer types, indicating the potential of PRMT5 as a therapeutic target. Small molecule drugs and chemical drugs are the most rapidly progressing drug types under the target PRMT5, with small molecule drugs being the primary focus. The United States, China, and Canada are the countries/locations with the highest development activity, with the United States leading in Preclinical stage and China showing progress in Phase 1. Overall, the current competitive landscape suggests a promising future for the development of PRMT5 inhibitors in the pharmaceutical industry. PRMT5 inhibitors entering Phase II clinical studies: GSK-3326595GSK-3326595 is a small molecule drug that is being developed by Epizyme, Inc. It is designed to target PRMT5, a protein involved in various cellular processes. The drug is being investigated for its potential therapeutic applications in neoplasms, immune system diseases, and hemic and lymphatic diseases. The active indications for GSK-3326595 include solid tumors, non-Hodgkin lymphoma, neoplasms, acute myeloid leukemia, and myelodysplastic syndromes. These are all serious and potentially life-threatening conditions that affect different parts of the body, including the blood, lymph nodes, and various organs. 👇Please click on the image below to directly access the latest data (R&D Status | Core Patent | Clinical Trial | Approval status in Global countries) of this drug. Currently, GSK-3326595 is in Phase 2 of clinical development, which means that it has already undergone initial testing in humans and has shown promising results in terms of safety and efficacy. Phase 2 trials typically involve a larger number of participants and aim to further evaluate the drug's effectiveness and side effects. As a small molecule drug, GSK-3326595 has the advantage of being able to penetrate cells and interact with specific targets, such as PRMT5. This targeted approach can potentially lead to more effective treatment options with fewer side effects compared to traditional chemotherapy or radiation therapy. Epizyme, Inc. is the originator organization behind GSK-3326595. They are a biopharmaceutical company focused on developing novel therapies for patients with genetically defined cancers and other diseases. With their expertise in epigenetics and targeted therapies, Epizyme is dedicated to advancing the field of biomedicine and improving patient outcomes. In summary, GSK-3326595 is a small molecule drug being developed by Epizyme, Inc. It targets PRMT5 and has potential applications in neoplasms, immune system diseases, and hemic and lymphatic diseases. The drug is currently in Phase 2 of clinical development and shows promise in treating solid tumors, non-Hodgkin lymphoma, acute myeloid leukemia, and myelodysplastic syndromes. Epizyme, Inc. is the organization behind the development of this innovative drug, aiming to provide new treatment options for patients in need. PRMT5 inhibitors entering PhaseⅠ/Ⅱclinical studies: AMG-193AMG-193 is a small molecule drug developed by Amgen, Inc. It falls under the therapeutic areas of neoplasms and respiratory diseases, specifically targeting PRMT5. The drug is primarily indicated for the treatment of non-small cell lung cancer and solid tumors. 👇Please click on the image below to directly access the latest data (R&D Status | Core Patent | Clinical Trial | Approval status in Global countries) of this drug. Amgen, Inc. is the originator organization behind AMG-193. Being a small molecule drug, AMG-193 is designed to interact with PRMT5, a target protein involved in various cellular processes. By specifically targeting PRMT5, the drug aims to inhibit its activity and potentially disrupt the growth and survival of cancer cells in non-small cell lung cancer and solid tumors. Neoplasms, or abnormal tissue growth, encompass a wide range of cancers. Non-small cell lung cancer is one of the most common types of lung cancer, accounting for approximately 85% of all cases. Solid tumors, on the other hand, refer to abnormal masses of tissue that can occur in various organs, such as the breast, colon, or prostate. The current development stage of AMG-193, Phase 1/2, suggests that the drug has undergone initial testing in a small group of patients to evaluate its safety, dosage, and potential efficacy. This phase typically involves assessing the drug's pharmacokinetics, side effects, and preliminary therapeutic effects. The fact that AMG-193 has obtained IND approval in China indicates that it has met the necessary regulatory requirements to proceed with clinical trials in the country. In summary, AMG-193 is a small molecule drug developed by Amgen, Inc. that targets PRMT5. It is indicated for the treatment of non-small cell lung cancer and solid tumors. The drug has reached Phase 1/2 on a global scale and has obtained IND approval in China, allowing for further clinical trials in the country.

关注并星标CPHI制药在线 倍半萜内酯是一大类次生代谢产物，绝大多数来源于菊科植物，具有抗肿瘤、抗炎、抗菌等多种生物活性。根据羧基骨架、取代基的类型和位置，倍半萜内酯类可分为吉马内酯（germacranolides）、愈创木内酯（guaianolides）、伪愈创木内酯（pseudoguaianolides）、桉烷内酯类（eudesmanolides）、榄香烷内酯（elemanolides）等。       近年来发现具有抗肿瘤活性的倍半萜内酯主要来源于青蒿素类、土木香内酯类、地胆草内酯类、鹅不食草内酯类、小白菊内酯类等。青蒿素是在菊科植物黄花蒿中发现的倍半萜内酯类化合物，其衍生物双氢青蒿素和青蒿琥酯对多种肿瘤具有显著的抑制作用。在土木香 Inula helenium L.中发现的具有抗肿瘤活性的倍半萜内酯类化合物主要有土木香内酯、异土木香内酯、木香烃内酯和去氢木香内酯。在地胆草Elephantopus scaber L.中发现的具有抗肿瘤活性的倍半萜内酯类化合物主要有去氧地胆草素、异去氧苦地胆苦素和地胆草种内酯等。在鹅不食草 Centipeda minima L.中发现的具有抗肿瘤活性的倍半萜内酯类化合物主要有山金车内酯 D和短叶老鹳草素。在小白菊 Tanacetum parthenium L.中发现的具有抗肿瘤活性的倍半萜内酯类化合物主要有小白菊内酯、二甲氨基小 白菊内酯、乌心石内酯、Epoxymicheliolide和Dimethylaminomicheliolide。       此外，从其他植物中分离的倍半萜内酯也具有肿瘤抑制作用，如从旋覆花属植物 Inula aucheriana 中分离得到的化合物旋覆花内酯 Britannin对多数肿瘤细胞具有抑制作用；来自中药白术 Atractylodes macrocephala中的倍半萜内酯有白术内酯Ⅰ、白术内酯Ⅱ；来自泥胡菜 Hemistepta lyrata Bunge的有Hemistepsin A；来自中药苍耳Xanthium strumarium L. 的有叶黄制菌素；来自肿柄菊Tithonia diversifolia A. Gray. 的有圆叶肿柄菊素 C tagitinin C；来自于毒伞芹 Thapsia garganica L. 的有毒胡萝卜素；来自牛樟芝Antrodia cinnamomea 的有 Antrocin；来自于旋覆花属植物 Inula oculus-christi 的有天人菊内酯。       倍半萜内酯类化合物的抗肿瘤作用机制       倍半萜内酯类天然产物抗肿瘤活性的作用机制主要包括氧化应激、铁死亡、诱导凋亡、诱导自噬以及调节和提高免疫力。       1氧化应激倍半萜内酯可通过抑制硫氧还蛋白还原酶（TrxR1）或核因子红细胞2相关因子2（Nrf2）诱导 ROS 的产生。土木香内酯在胃癌细胞 BGC-823和SGC-7901 中，通过抑制 TrxR1 的活性诱导 ROS 生成，进而激活 MAPK 通路，最终诱导肿瘤细胞的凋亡。土木香内酯可通过 ROS 积累和内质网应激，抑制三阴乳腺癌细胞 MDAMB-231 细胞活性。此外，土木香内酯在食管腺癌细胞 KYAE-1中，可下调 Nrf2 表达，诱导细胞内ROS 积累，进而诱导细胞凋亡。       2铁死亡铁死亡是一种铁依赖性的调节性细胞死亡形式，是由细胞膜上的脂质过氧化物的毒性积累引发的。青蒿素和双氢青蒿素在非小细胞肺癌A549细胞中，可下调铁死亡的核心负调节器胱氨酸/谷氨酸转运体（xCT），上调铁死亡正向调节因子转铁蛋白受体（TFRC）的 mRNA 水平，诱导 A549 细胞铁死亡。去氧地胆草素及其衍生物DETD-35 在黑色素瘤细胞 A375 和A375-R中，可重塑谷胱甘肽和初级代谢、脂质/氧脂质代谢并造成线粒体损伤，诱导黑色素瘤细胞的脂质ROS 积累并触发铁死亡。       3诱导凋亡细胞凋亡是肿瘤细胞程序性死亡最重要的途径。大多数倍半萜内酯是通过诱导肿瘤细胞凋亡达到抗肿瘤的目的。乌心石内酯能上调肝癌细胞HepG2 和 Hepa 1-6 中细胞凋亡诱导因子（AIF）和细胞色素 C 的表达，诱导凋亡。木香烃内酯在结直肠癌细胞 HCT-15、HCT-116 和DLD1中，通过激活和诱导 p53 的稳定性，诱导凋亡。异木香内酯在食管鳞癌细胞 KYSE30中，上调 PDCD4 的表达，下调Bcl-xL和XIAP的表达，诱导细胞凋亡。青蒿琥酯可使荷 H22肝癌小鼠的实体瘤组织标本中的 Bax 基因表达增加、Bcl-2 基因表达减少、Bcl -2 /Bax 比例下降，表明青蒿琥酯可下调PCNA和Bcl-2的表达、上调 Bax 的表达，诱导细胞凋亡。小 白菊内酯( PN) 能诱导多发性骨髓瘤细胞凋亡，而正常淋巴细胞在同等条件下不受影响。PN 的凋亡活性是通过引起MM细胞的氧化应激而介导的，并进一步推测 NADPH 的氧化活性与PN介导的MM 细胞ROS的产生相关。泽兰内酯可上调Hela 细胞 p53 的表达、上调 Bax 的表达、下调 Bcl-2 的表达，使Bcl-2 /Bax比值降低，诱导细胞凋亡。       4细胞自噬细胞自噬可介导细胞凋亡和细胞周期阻滞。例如青蒿琥酯在膀胱癌细胞T24和EJ中可诱导自噬，随后激活细胞凋亡，且 AMPK-mTORULK1 途径参与自噬和凋亡的过程。小 白菊内酯在胰 腺癌细胞 Panc-1中，可诱导肿瘤细胞自噬，并显著上调 p62/SQSTM1、 Beclin 1和LC3Ⅱ的表达，最终诱导凋亡。青蒿素和双氢青蒿素在上皮性卵巢癌细胞 SKOV3 中，可阻滞细胞周期在 G2/M 期，且诱导自噬。       5双向调节和提高免疫力灌胃给予S180 荷瘤小鼠青蒿琥酯，青蒿琥酯60、30、15 g·kg-1·d -1均能显著抑制S180 的生长和升高S180荷瘤小鼠血清 IgG 的抗体水平，对2，4-二硝基氟苯( DNFB) 诱导的迟发性超敏反应有增强作用，并可诱导淋巴细胞转化为淋巴母细胞，提高小鼠的免疫功能。双氢青蒿素对豆蛋白 A( ConA) 诱导的小鼠 T 细胞的增殖有明显的抑制作用，是一种潜在的免疫抑制剂。异土木香内酯对人肝肿瘤细胞( HLE) 的增殖具较强的抑制活性，还对小鼠移植性肿瘤 H22的生长有抑制作用，并且不降低荷瘤小鼠的胸腺指数和脾指数，推测异土木香内酯有可能是通过提高机体的免疫能力来实现其抗肿瘤活性的。       倍半萜内酯类化合物与抗肿瘤药物的联用       肿瘤耐药性是肿瘤治疗的一大障碍，越来越多的研究表明，将天然产物与抗肿瘤药物联用可以带来更好的治疗效果。在倍半萜内酯类化合物与抗肿瘤药物的联用中，主要是与化疗、放疗和免疫治疗联用。倍半萜内酯类化合物可与多种化疗药物联用，对多种肿瘤细胞的增殖有抑制作用，可达到增敏、增效的协同作用。在联合放疗中，乌心石内酯可增强X线对宫颈癌Hela 细胞的抑制作用和凋亡诱导作用，抑制 HeLa 细胞的硫氧还蛋白还原酶（TrxR）活性，诱导活性氧（ROS）生成。Dimethylaminomicheliolide 可提高小鼠结直肠癌细胞 CT26 和胶质母细胞瘤细胞 GL261 对放疗的敏感，诱导 ROS 生成、细胞凋亡和 DNA双链断裂，且可与抗 PD-L1 抗体（α-PD-L1）结合，产生协同抗肿瘤效果。双氢青蒿素可通过抑制冷诱导 RNA 结合蛋白（CIRBP）的表达减少肺癌 A549细胞的线粒体自噬和辐射抗性，敲除CIRBP 基因可抑制 A549R 细胞的线粒体自噬和辐射抗性，与双青蒿素联用可进一步抑制 A549R 细胞的线粒体自噬和辐射抗性。Antrocin 与放疗联用可抑制前列腺癌 DAB2IP 基因敲除抗辐射细胞系（LAPC4-KD 和 PC3-KD）及 shControl 细胞系（LAPC4-Con 和 PC3-Con）的增殖并诱导其凋亡，下调 PI3K/AKT 和 MAPK信号通路，调节细胞周期并诱导凋亡。在联合免疫治疗中，青蒿素可增敏人慢性髓原白血病 K562 细胞和淋巴瘤 Raji 细胞以及小鼠淋巴瘤 YAC-1 细胞对 NK 细胞介导的细胞溶解。白术内酯Ⅰ可显著促进人结直肠癌细胞 HCT116、 SW837 和小鼠结直肠癌细胞 MC38、CT26 的肿瘤抗原呈递，增强 CD8+T细胞的细胞毒性反应，提高肿瘤对免疫疗法的反应。       目前，倍半萜内酯类中以小白菊内酯为基础合成的Dimethylaminomicheliolide 和以毒胡萝卜素为基础合成的 Mipsagargin 均已进入临床试验阶段，展示出巨大的潜力。倍半萜内酯类天然产物不仅可抑制耐药肿瘤细胞，在药物联用中也呈现增敏、增效的作用，倍半萜内酯类化合物可增加细胞对化疗药物、放疗射线以及免疫疗法的敏感性，产生协同作用，增强细胞毒性，诱导细胞凋亡。所以寻找抗肿瘤药物作用的新靶点，研究开发天然抗癌新药，可以降低化疗的成本，更能减轻肿瘤患者的痛苦，使更多的肿瘤患者都能得到及时、有效的治疗，提高肿瘤患者的生活质量。       参考资料       [1]朱华野,朴惠顺.倍半萜内酯类化合物抗肿瘤作用机制的研究进展[J].华西药学杂志,2015,30(03):381-383.       [2]林金榕,陈四保.倍半萜内酯类天然产物抗肿瘤活性及机制研究进展[J].中南药学,2023,21(06):1589-1598.       作者简介       小米虫，药品质量研究工作者，长期致力于药品质量研究及药品分析方法验证工作，现就职于国内某大型药物研发公司，从事药品检验分析及分析方法验证。智药研习社近期直播报名来源：CPHI制药在线声明：本文仅代表作者观点，并不代表制药在线立场。本网站内容仅出于传递更多信息之目的。如需转载，请务必注明文章来源和作者。投稿邮箱：Kelly.Xiao@imsinoexpo.com▼更多制药资讯，请关注CPHI制药在线▼点击阅读原文，进入智药研习社~

具有巨大结构多样性的天然产物对各种疾病具有治疗作用，大约25%-50%的上市药物来源于天然产品。含有亲电基团的一类天然产物能够与蛋白质的亲核试剂形成不可逆键。 具有巨大结构多样性的天然产物对各种疾病具有治疗作用，大约25%-50%的上市药物来源于天然产品。含有亲电基团的一类天然产物能够与蛋白质的亲核试剂形成不可逆键。这些共价抑制剂被认为具有提高药效、选择性和药效持续时间的优势，这表明来自天然来源的共价抑制剂为药物发现和开发提供了丰富的资源。 Eriocalycin B（EB）、17-羟基jolkinolide B（HJB）、孤雌内酯（PN）、黄原胶（XT）和穿心莲内酯（AG）是具有多种抗癌活性的萜类天然产物，通常带有亲电基团（α、β-不饱和羰基和/或环氧化物），能够共价修饰蛋白质半胱氨酸残基。然而，它们的直接靶点和潜在的分子机制在很大程度上仍不清楚，这限制了这些化合物的发展。 图片来源：https://doi.org/10.1038/s41401-023-01072-z 近日，来自上海药物研究的研究者们在Acta Pharmacol Sin.杂志上发表了题为“Investigation of targets and anticancer mechanisms of covalently acting natural products by functional proteomics”的文章，该研究揭示了天然产物的共价修饰靶点及其抗肿瘤活性的潜在分子机制。 在这项研究中，研究者进行了基于TMT的定量蛋白质组学分析，以在全系统范围内识别显著差异表达的蛋白质和调节的途径。途径富集分析显示，所有这五种天然产物都影响了泛素介导的蛋白水解途径。由于EB和PN具有更高的增殖抑制活性，研究者开发了一个ABPP平台来识别它们优先修饰的靶标以及确切的共价结合位点。 定量蛋白质组学和ABPP实验都表明PN与蛋白质泛素化事件有关，Western印迹分析进一步验证了这一点。选择PN的潜在靶点USP10进行进一步验证。体外结果显示PN共价修饰了USP10，并对USP10的功能产生了抑制作用。与阴性对照细胞相比，USP10敲低MDAMB-231细胞对PN介导的细胞生长抑制具有显著的抗性。这些结果表明，PN通过至少部分共价结合USP10来抑制MDA-MB231细胞的增殖。值得注意的是，PN含有一个α，β-不饱和羰基和一个环氧化物，这两个基团都能修饰半胱氨酸。需要对结构-活性关系进行进一步研究，以阐明该化合物的药效团。 PN处理样品中USP10下游底物的蛋白质表达变化显示，RAF1、RPS2和SKP2的表达水平显著下调。RAF1是RAS激活和下游MEK-ERK信号传导之间的关键环节，参与增殖、分化和凋亡等多种细胞过程。RPS2在恶性前列腺癌症样本中过度表达，可能成为潜在的治疗靶点。SKP2是SCF（SKP1-CUL1-F-box蛋白）E3泛素蛋白连接酶复合物的底物识别成分，通过降解程序性细胞死亡蛋白4（PDCD4）促进乳腺癌症。 EB和PN的显著差异表达蛋白的蛋白-蛋白相互作用网络。 图片来源：https://doi.org/10.1038/s41401-023-01072-z 综上所述，EB和PN可能具有相似的分子机制，部分是通过调节蛋白泛素化，而ABPP的结果表明EB和PN可以与不同的靶标相互作用。这些关于EB潜在靶点的线索可能有助于理解EB影响的乳腺癌症细胞增殖的分子机制，这仍需要通过其他独立实验进一步验证。（生物谷 Bioon.com） 参考文献 Wen-si Zhao et al. Investigation of targets and anticancer mechanisms of covalently acting natural products by functional proteomics. Acta Pharmacol Sin. 2023 Mar 17. doi: 10.1038/s41401-023-01072-z.