PIN1

本文将近期药物研发新兴靶标进行汇总，涵盖肿瘤、代谢、呼吸系统等领域，这些靶标一般是近期报道的具有一定治疗潜力的新型靶标，以期为科研人员提供参考。新型靶标的发现是药物研发的关键。本文就近期在国际知名期刊报道的新型药物靶标的研发进展进行汇总（表1），并参考数据库对不同靶标的候选药物研发进展进行阐述。表1：近期报道的新型药物靶标列举Pin1蛋白的SUMOylation（SUMO化修饰）是近年来备受关注的一类蛋白翻译后修饰，高度的蛋白SUMO化促进了结直肠癌、乳腺癌和脑癌等多种肿瘤发展。近期，在Nature Communications上发表了题为“Stabilization of Pin1 by USP34 promotes Ubc9 isomerization and protein sumoylation in glioma stem cells”的文章（Ref 1），其发现Pin1蛋白在胶质瘤干细胞（GSC）中被去泛素化酶USP34稳定而高表达，且Pin1通过催化已知唯一的SUMO E2酶Ubc9来促进GSC中的全局蛋白SUMO化，并揭示了调控Pin1/USP34、Pin1/Ubc9结合的多个激酶，为靶向Pin1蛋白和全局蛋白SUMO化治疗包括胶质瘤在内的癌症提供了多个潜在药物靶标，具有十分重要的基础与转化意义。在该研究中，使用Pin1抑制剂Sulfopin和CDK1抑制剂RO3306联合治疗荷瘤小鼠，有效抑制了GSC中的SUMO1型蛋白SUMO化修饰，减缓了小鼠颅内胶质母细胞瘤（GBM）的生长，极大延长了小鼠生存期。总之，该研究阐明了肿瘤中调控Pin1蛋白稳定性的上游机制，剖析了Pin1上调SUMO1型蛋白SUMO化的下游机制，有助于发展针对GBM和其它受Pin1驱动的恶性肿瘤的治疗新策略。OTUB2肿瘤免疫逃逸给肿瘤的治疗带来了极大障碍。PD-1/PD-L1通路是肿瘤细胞进行免疫逃逸的关键通路。近期，在Nature Communications上发表了题为“Pharmaceutical targeting of OTUB2 sensitizes tumors to cytotoxic T cells via degradation of PD-L1”的文章（Ref 2），确定了肿瘤细胞表达的Otubain-2（OTUB2）是抗肿瘤免疫的负调控因子，通过PD-1/PD-L1信号通路在各种人类癌症中发挥作用，并表明OTUB2具有成为肿瘤诊断和治疗靶标的潜力。在该研究中，通过对TCGA数据分析，发现OTUB2与T细胞活化基因表达呈负相关。随后，通过免疫沉淀质谱等方法，发现了OTUB2和PD-L1存在相互作用，其中PD-L1的ICD结构域以及OTUB2酶活部位的第51位半胱氨酸对OTUB2与PD-L1的相互作用至关重要。在机制方面，OTUB2与PD-L1相互作用，并通过干预内质网蛋白降解（ERAD）通路使PD-L1蛋白去泛素化和稳定。总之，该研究揭示了去泛素化酶OTUB2通过去泛素化作用稳定PD-L1从而促进肿瘤免疫逃逸的机制，并提出了利用靶向OTUB2的功能抑制剂来降低肿瘤细胞PD-L1表达水平，增强细胞毒性T细胞抗肿瘤免疫应答的肿瘤治疗策略。STK24丝氨酸/苏氨酸激酶STK24属于Ste20家族的生发中心激酶（GCK）Ⅲ亚家族，主要涉及激活调控多种细胞功能（包括细胞凋亡和细胞迁移）的丝裂原活化蛋白激酶（MAPK）级联反应。近期，在Advanced Science上发表了题为“Protein Kinase STK24 Promotes Tumor Immune Evasion via the AKT-PD-L1 Axis”的文章（Ref 3），其揭示了STK24在通过磷酸化AKT和促进PD-L1表达来协调肿瘤免疫逃逸反应中的关键作用，并且通过STK24抑制有效克服了肿瘤对抗PD-1疗法的内在抵抗。研究发现STK24通过削弱肿瘤免疫力来促进肿瘤发生。在免疫缺陷小鼠中，STK24缺陷对肿瘤形成没有明显影响，但在免疫正常的小鼠中显著阻碍肿瘤生长，并伴随着细胞毒性CD8+T细胞和自然杀伤（NK）细胞在肿瘤组织中的增加浸润。进一步发现，STK24通过磷酸化AKT的一个先前未被发现的Thr21位点来增强肿瘤细胞中PD-L1的表达。STK24缺陷显著提高了抗PD-1免疫治疗的疗效。STK24的表达水平与AKT Thr21磷酸化和PD-L1的表达呈正相关，与CD8+T细胞的浸润和患者的生存结果呈负相关。总之，该研究表明STK24可能是开发更有效的免疫治疗干预措施的潜在靶标。PAK4化疗是治疗晚期非小细胞肺癌（NSCLC）的主要方法，使用顺铂的化疗是一线治疗的主要方法。顺铂通过诱导凋亡直接杀死癌细胞，但长期使用顺铂常常导致耐药。p21活化激酶（PAKs）是一个丝氨酸/苏氨酸（Thr）蛋白激酶家族，与许多致癌信号通路密切相关。PAKs在基因转录、细胞骨架重组、致癌转化、细胞增殖和细胞侵袭等方面发挥调控作用。近期，在Cell Death Discovery上发表了题为“Targeting PAK4 reverses cisplatin resistance in NSCLC by modulating ER stress”的文章（Ref 4），其揭示PAK4可能是NSCLC化疗耐药性的一个有价值的治疗靶标。研究数据表明，通过抑制GRP78表达，PAK4敲低可通过调节内质网应激来促进NSCLC对顺铂的敏感性。这为顺铂耐药的机制研究提供新见解。【参考资料】1. 科睿唯安CDDI数据库, 检索日期: 2024年1月23日.2. 生物世界、转化医学网、BioArt、医药观澜、iNature、学术经纬等公开网络资源.声明：发表/转载本文仅仅是出于传播信息的需要，并不意味着代表本公众号观点或证实其内容的真实性。据此内容作出的任何判断，后果自负。若有侵权，告知必删！长按关注本公众号   粉丝群/投稿/授权/广告等请联系公众号助手 觉得本文好看，请点这里↓

WATERTOWN, Mass., Oct. 25, 2023 (GLOBE NEWSWIRE) -- Larkspur Biosciences, a biotechnology company building precision therapies to outsmart cancer, announced that data supporting development of a novel investigational therapy targeting Pin1 will be featured in a poster presentation at the 38th Annual Meeting of the Society for Immunotherapy of Cancer (SITC 2023) on November 3 in San Diego, CA. The data look at how the potential therapy will target Pin1 to program fibroblasts to drive a pro-immune response at the tumor. “Larkspur Biosciences was founded to pursue targets shared by cancer and immune cells that the cancer hijacks to evade immunity. Our data at SITC 2023 demonstrates that Pin1 is a promising cancer–fibroblast target to pursue for therapeutic interventions,” said Catherine Sabatos-Peyton, PhD, CEO of Larkspur Biosciences. “Standard of care immunotherapy has revolutionized cancer treatment, but less than 30 percent of patients respond. At Larkspur, we believe there is an opportunity to leverage targets shared by both the cancer and the immune system as a more effective way to activate the immune system against cancer.” Presentation Details: Poster: Abstract 1433 Title: "Targeting peptidyl-prolyl isomerase Pin1 to modulate cancer-associated fibroblast phenotype and TGF-beta signaling" Time: Friday, November 3, 12-1:30pm and 5:10-6:40pm PT Location: San Diego Convention Center, Exhibit Halls A and B1 Presenter: Melvyn Chow, PhD, Associate Director, Biology, Larkspur Biosciences About Larkspur Biosciences Larkspur Biosciences is building precision therapies to outsmart cancer. Larkspur’s approach targets the unique ways that tumors hijack the immune system by using pathways shared by cancer and immune cells, developing precision therapies for molecularly defined patient populations in order to overcome these bottlenecks. The company is advancing its first-in-class programs to outsmart the tumor and enable robust and sustained responses in colorectal cancer (CRC) and beyond. LarkX, the company’s target discovery platform, leverages tumor genetics from patient-derived data to fuel its pipeline and offers the opportunities to address multiple types of cancer. Visit us at and follow us on LinkedIn and X. CONTACT: Adam Silverstein Scient PR adam@scientpr.com

Researchers have achieved a significant breakthrough in identifying the primary cause and potential treatment for preeclampsia, a severe pregnancy complication. Experts pinpointed a toxic protein named cis P-tau in the blood and placenta of individuals with preeclampsia. The study describes cis P-tau as a pivotal circulating instigator of preeclampsia. An antibody developed in 2012 to target only the toxic protein while leaving its healthy counterpart unscathed is currently undergoing clinical trials in human patients suffering from traumatic brain injury and Alzheimer's Disease. The antibody has shown promising results in animal models and human cell cultures in treating the brain conditions. Upon testing this antibody in mice, the researchers found the all symptoms associated with preeclampsia were corrected. Researchers from Western and Brown University have made groundbreaking progress towards identifying the root cause and potential therapy for preeclampsia. The pregnancy complication affects up to eight per cent of pregnancies globally and is the leading cause of maternal and fetal mortality due to premature delivery, complications with the placenta and lack of oxygen. The research, led by Drs. Kun Ping Lu and Xiao Zhen Zhou at Western, and Drs. Surendra Sharma and Sukanta Jash at Brown, has identified a toxic protein, cis P-tau, in the blood and placenta of preeclampsia patients. According to the study published in Nature Communications, cis P-tau is a central circulating driver of preeclampsia -- a "troublemaker" that plays a major role in causing the deadly complication. "The root cause of preeclampsia has (so far) remained unknown, and without a known cause there has been no cure. Preterm delivery is the only life-saving measure," said Lu, professor of biochemistry and oncology at Schulich School of Medicine & Dentistry. Lu is also a Western Research Chair in Biotherapeutics. "Our study identifies cis P-tau as a crucial culprit and biomarker for preeclampsia. It can be used for early diagnosis of the complication and is a crucial therapeutic target," said Sharma, who recently retired from his Brown roles as a professor of pathology and laboratory medicine (research) and professor of pediatrics (research). In 2016, Sharma, a leading preeclampsia researcher, and his team had identified that preeclampsia and diseases like Alzheimer's had similar root causes related to protein issues. This research builds on that finding. Until now, cis P-tau was mainly associated with neurological disorders like Alzheimer's disease, traumatic brain injuries (TBI) and stroke. This association was discovered by Lu and Zhou in 2015 as a result of their decades of research on the role of tau protein in cancer and Alzheimer's. An antibody developed by Zhou in 2012 to target only the toxic protein while leaving its healthy counterpart unscathed is currently undergoing clinical trials in human patients suffering from TBI and Alzheimer's Disease. The antibody has shown promising results in animal models and human cell cultures in treating the brain conditions. The researchers were curious whether the same antibody could work as a potential treatment for preeclampsia. Upon testing the antibody in mouse models they found astonishing results. "In this study, we found the cis P-tau antibody efficiently depleted the toxic protein in the blood and placenta, and corrected all features associated with preeclampsia in mice. Clinical features of preeclampsia, like elevated blood pressure, excessive protein in urine and fetal growth restriction, among others, were eliminated and pregnancy was normal," said Sharma. Sharma and his team at Brown have been working on developing an assay for early detection of preeclampsia and therapies to treat the condition. He believes the findings of this study have brought them closer to their goal. Black and Hispanic women more susceptible The tragic death of American track and field champion Tori Bowie earlier this year put the spotlight on preeclampsia, which disproportionately impacts Black and Hispanic women. A gold, silver and bronze medalist in the 2016 Olympic Games, Bowie, 32, was found dead in her bed on May 2, 2023, while approximately eight months pregnant. According to the autopsy report the complications may have involved eclampsia -- a severe form of preeclampsia. "Research has shown that women of certain races have genes that could possibly lead to higher than average blood pressure levels, eventually creating conditions for preeclampsia during pregnancy. However, it's also true that in many low socio-economic countries there's no registry to record PE cases. So, its link to other environmental factors is still unclear," said Sharma. Preeclampsia and the brain Recent research has also thrown light on preeclampsia's long-term impacts and possible links to brain health. "Preeclampsia presents immediate dangers to both the mother and fetus, but its long-term effects are less understood and still unfolding," said Sharma. "Research has suggested a heightened risk of dementia later in life for both mothers who have experienced preeclampsia and their children." However, the causal link between preeclampsia and dementia is not known. The researchers say this new study has pinpointed a potential underlying cause of the complex relationship between preeclampsia and brain health. "Our study adds another layer to this complexity. For the first time, we've identified significant levels of cis P-tau outside the brain in the placenta and blood of preeclampsia patients. This suggests a deeper connection between preeclampsia and brain-related issues," said Jash, the lead author of the study. As researchers delve deeper, how our bodies respond to stress is also emerging as a potential factor in the onset of preeclampsia. "Although genetics play a role, factors like stress could be an important piece of the puzzle. Understanding how stress and other environmental factors intersect with biological markers like cis P-tau may offer a more complete picture," said Jash, assistant professor of molecular biology, cell biology and biochemistry (research) and pediatrics (research) at Brown. A stress-response enzyme called Pin1 In 1996 and 1997, Lu and Zhou made the groundbreaking discovery of Pin1, which turns out to be a stress-response enzyme. This is a specific protein in the cells that becomes active or changes its behaviour in response to stressors, such as environmental challenges, toxins or physiological changes. "Pin1 plays a pivotal role in keeping proteins, including the tau protein, in the functional shape during stress. When Pin1 becomes inactivated, it leads to the formation of a toxic, misshapen, variant of tau -- cis P-tau," said Zhou, associate professor, pathology and laboratory medicine at Schulich Medicine & Dentistry. Interestingly, Pin1 is a key player in cancer signalling networks, turning on numerous cancer-causing proteins and turning off many cancer-suppressing ones. Found in high levels in most human cancers, it's particularly active in cancer stem cells, which are thought to be central to starting and spreading tumors and are hard to target with existing treatments. "Essentially, when Pin1 is activated, it can lead to cancer. On the other hand, when there's a decrease or deactivation in Pin1, it results in the formation of the toxic protein cis P-tau, which leads to memory loss in Alzheimer's and after TBI or stroke. Now, we've uncovered its connection to preeclampsia as well," said Zhou. "The results have far-reaching implications. This could revolutionize how we understand and treat a range of conditions, from pregnancy-related issues to brain disorders," said Lu. Lu and Sharma had met at Brown in 2019, where Lu was invited to give a lecture on his research. Following an engaging session and a few dinners together, a collaboration between the Western researchers and Brown was forged. "Science surprises us. I had never thought of working on finding a therapy for preeclampsia. It also shows that a collaboration can be transformative."