NPRL2

引言外周血CD8+ T细胞数量受到严格控制，但调控这一过程的确切分子机制仍不完全清楚。2024年5月20日，上海交通大学苏冰团队在Cell Discovery 发表题为“DEPDC5 protects CD8+ T cells from ferroptosis by limiting mTORC1-mediated purine catabolism”的研究论文，该研究发现DEPDC5功能丧失突变的癫痫患者外周CD8+ T细胞减少，DEPDC5表达与肿瘤浸润CD8+ T细胞以及癌症患者总体生存率呈正相关，表明DEPDC5可能控制外周CD8+ T细胞稳态。值得注意的是，具有T细胞特异性Depdc5缺失的小鼠外周 CD8+ T 细胞也减少并受损抗肿瘤免疫。从机制上讲，由于mTORC1 诱导的ATF4表达，Depdc5缺陷的 CD8+ T细胞产生高水平的黄嘌呤氧化酶和脂质 ROS，导致自发性铁死亡。总之，该研究将 DEPDC5介导的mTORC1信号传导与CD8+ T细胞对铁死亡的保护联系起来，从而揭示了一种通过抑制铁死亡来增强抗肿瘤免疫的新策略。维持足够的外周CD8+ T细胞数量对于针对病原体感染产生强大的宿主免疫反应至关重要，抗肿瘤免疫反应的有效性也与肿瘤微环境中浸润的功能性CD8+T细胞的数量呈正相关。外周T细胞数量受到稳态机制的严格调节，以在整个成年期保持总种群规模相对恒定。该过程需要MHC I识别和IL-7等细胞因子来维持CD8+ T细胞凋亡和稳态周转的存活。然而，这些稳态机制是否与T细胞代谢途径以及其他类型的细胞死亡相交仍然不清楚。雷帕霉素 （mTOR） 的机制靶标是一种进化上保守的蛋白激酶，可关键调节细胞生长、增殖和代谢。当氨基酸或葡萄糖供应受限时，mTOR复合体1 (mTORC1)的激活受到针对破片的缺口活性(GATOR) 1的抑制。DEPDC5，一种已知的癫痫风险基因，编码含DEP结构域蛋白 （DEPDC）5，是GATOR1的重要组成部分，还包含 NPRL2 和 NPRL3。激活的 mTORC1 磷酸化翻译调节因子 S6K和4E-BP1，通过上调多种代谢途径导致核糖体生物发生和蛋白质翻译增加。因此，mTORC1介导的代谢产生一系列中间化合物，其中许多化合物与一种新发现的称为铁死亡的程序性细胞死亡形式有关。铁死亡是由多不饱和脂肪酸（PUFA）的铁依赖性氧化和脂质氢过氧化物（L-OOH）致死水平的积累引发的一种调节性细胞死亡形式。氧化多不饱和脂肪酸（ox-PUFA）是已知与铁死亡相关的铁依赖性脂质过氧化的最著名产物。氧化多不饱和脂肪酸的生产需要过氧化氢(H2O2)和亚铁(Fe2+)通过芬顿反应生成羟基自由基(OH.)。在生理条件下，脂质修复系统利用谷胱甘肽和谷胱甘肽过氧化物酶4（GPX4）以及辅酶Q10和铁死亡抑制蛋白1（FSP1）将L-OOH转化为无毒脂质醇（L-OH）来抑制铁死亡。铁死亡也可以使用亲脂性抗氧化剂或铁螯合剂来抑制。维生素E是一种众所周知的ROS清除剂，在体内和体外也被证明可以有效抑制铁死亡，这表明自由基是铁死亡的最重要诱因之一。铁死亡抑制剂DFO可恢复Depdc5tko小鼠的抗肿瘤免疫（Credit: Cell Discovery）选择性诱导癌细胞铁死亡已被提议作为抗肿瘤治疗的潜在策略。然而，最近的几项研究表明，CD8+ T 细胞的铁死亡也会损害抗肿瘤免疫力。一项早期研究表明，T 细胞特异性 Gpx4 缺失可增强 CD8+ 群体的铁死亡。在最近的一项研究中，观察到CD8+ T细胞在体外比肿瘤细胞对铁死亡更敏感。鉴于CD8+ T细胞数量对于强大的宿主免疫至关重要，因此了解在体内控制该群体的分子机制非常重要。在这项研究中，发现功能丧失的癫痫患者 DEPDC5 突变的外周CD8+ T细胞减少，而高 DEPDC5 表达与 CD8+ T细胞的肿瘤浸润以及癌症患者的总体生存率呈正相关。使用 T 细胞特异性 Depdc5 条件敲除小鼠模型，研究证明 DEPDC5 保护 CD8+ T细胞免受铁死亡，并且是 CD8+ T细胞介导的抗肿瘤免疫所必需的。在分子水平上，DEPDC5 缺陷导致高 mTORC1活性诱导ATF4表达，进而增加黄嘌呤氧化酶（XO）和脂质ROS的表达，导致铁死亡。总之，研究揭示了 DEPDC5 在保护 CD8+ T 细胞免受ROS诱导的铁死亡方面的新作用，并揭示了一种通过抑制铁死亡来促进抗肿瘤免疫的策略。原文链接https://doi.org/10.1038/s41421-024-00682-z责编|探索君排版|探索君文章来源|“iNature”End往期精选围观一文读透细胞死亡(Cell Death) | 24年Cell重磅综述（长文收藏版）热文Nature | 破除传统：为何我们需要重新思考肿瘤的命名方式热文Nature | 2024年值得关注的七项技术热文Nature | 自身免疫性疾病能被治愈吗？科学家们终于看到了希望热文CRISPR技术进化史 | 24年Cell综述

Compelling Data Validates the Potential of Reqorsa® Immunogene Therapy and the Oncoprex® Delivery System as Innovative Cancer Treatments REQORSA Has Anti-Tumor Mechanisms and Ability to Trigger Cancer Cell Death AUSTIN, Texas, April 9, 2024 /PRNewswire/ -- Genprex, Inc. ("Genprex" or the "Company") (NASDAQ: GNPX), a clinical-stage gene therapy company focused on developing life-changing therapies for patients with cancer and diabetes, today announced that its research collaborators presented positive preclinical data for Reqorsa® Immunogene Therapy (quaratusugene ozeplasmid) and NPRL2 gene therapy, which both utilize the Company's non-viral Oncoprex® Delivery System for the treatment of lung cancer. These studies were presented at the 2024 American Association for Cancer Research (AACR) Annual Meeting, which is being held April 5-10, 2024 in San Diego, California. "We continue to expand our growing body of preclinical evidence supporting REQORSA's therapeutic potential to treat a variety of cancers, as well as the therapeutic potential of our non-viral delivery system to deliver tumor suppressor genes for the treatment of cancer," said Rodney Varner, Chairman, President and Chief Executive Officer at Genprex. "We are especially delighted to have three preclinical studies presented at one of the largest professional cancer research meetings among the world's top oncologists and the cancer research community." Featured Genprex-supported posters presented at AACR 2024 include: Title: "Quaratusugene ozeplasmid mediated TUSC2 upregulation in EML4-ALK bearing Non-Small Cell Lung Carcinoma can induce cellular apoptosis" Session Category: Molecular/Cellular Biology and Genetics Session Title: Apoptosis and Ferroptosis Session Date and Time: Sunday, April 7 from 1:30 p.m. – 5:00 p.m. PT Location: Poster Section 15 Poster Board Number: 7 Abstract Presentation Number: 351 Title: "Mechanism of NPRL2 gene therapy induced anti-tumor immunity in KRAS/STK11mt aPD1 resistant metastatic NSCLC" Session Category: Immunology Session Title: Inflammation, Host Factors, and Epigenetic Influences on Cancer Development and Treatment Session Date and Time: Monday, April 8 from 9:00 a.m. – 12:30 p.m. PT Location: Poster Section 5 Poster Board Number: 18 Abstract Presentation Number: 1420 Title: "Tumor Suppressor Gene TUSC2 suppresses energy metabolism in lung cancer cells with opposite effects in normal bronchial epithelial cells" Session Category: Experimental and Molecular Therapeutics Session Title: Cancer Biology and Metastasis Session Date and Time: Monday, April 8 from 1:30 p.m. – 5:00 p.m. PT Location: Poster Section 22 Poster Board Number: 6 Abstract Presentation Number: 3158 In the first poster, entitled "Quaratusugene ozeplasmid mediated TUSC2 upregulation in EML4-ALK bearing Non-Small Cell Lung Carcinoma can induce cellular apoptosis," researchers reported that REQORSA induced apoptosis in alectinib resistant EML4-ALK positive non-small cell lung cancer (NSCLC) cell lines. Alectinib is an ALK-inhibitor commonly used to treat patients with ALK rearrangements such as EML4-ALK positive NSCLCs. This research suggests that REQORSA may be an effective treatment in patients progressing on alectinib. The second poster, entitled, "Mechanism of NPRL2 gene therapy induced anti-tumor immunity in KRAS/STK11mt aPD1 resistant metastatic NSCLC" detailed a humanized mouse model study in which the researchers investigated the anti-tumor immune responses to NPRL2 gene therapy in pembrolizumab resistant KRAS/STK11mt NSCLC. In the study, lung metastases in humanized mice were treated through I.V. injection of NPRL2 nanoparticles, made with the ONCOPREX Delivery System, with or without pembrolizumab. The study found that the NPRL2 treatment by itself led to a marked decrease in the size of lung metastases but pembrolizumab had no effect. Additionally, a greater anti-tumor effect was seen in humanized compared to non-humanized mice, demonstrating that immune cells play a role in the effects of the NPRL2 nanoparticle therapy. Study findings suggest that NPRL2 gene therapy induces anti-tumor activity against KRAS/STK11mt tumors through dendritic cell-mediated antigen presentation and cytotoxic immune cell activation. The Company believes this data could support the potential for a new drug candidate in its pipeline, and it also provides further evidence for the Company's belief that the ONCOPREX Delivery System has the ability to be successful using genes other than the TUSC2 gene the Company is already using in clinical trials with REQORSA. In the third poster, entitled, "Tumor Suppressor Gene TUSC2 suppresses energy metabolism in lung cancer cells with opposite effects in normal bronchial epithelial cells" researchers reported that TUSC2-deficient cancer cells consistently exhibited decreased glycolytic rates and mitochondrial ATP production, leaving these cells without enough energy to support their vital functions. By comparison, when Beas2B, a normal human bronchial epithelial cell line with normal levels of TUSC2, was transfected with a TUSC2 containing plasmid, the glycolytic rate and mitochondrial metabolism was increased. This suggests the mechanism by which REQORSA treatment affects immune and other non-cancerous cells that leads to increased immune response against tumors. The study further suggested that REQORSA may play an important role as a cancer treatment to target and disrupt the metabolism of cancer cells, leading to a decrease in the rate of glycolysis. These AACR posters have been made available on Genprex's website at . About Reqorsa® Therapy REQORSA (quaratusugene ozeplasmid) for NSCLC and small cell lung cancer (SCLC) consists of the TUSC2 gene expressing plasmid encapsulated in non-viral nanoparticles made from lipid molecules (Genprex's ONCOPREX Delivery System) with a positive electrical charge. REQORSA is injected intravenously and specifically targets cancer cells, which generally have a negative electrical charge. REQORSA is designed to deliver the functioning TUSC2 gene to cancer cells while minimizing their uptake by normal tissue. REQORSA has a multimodal mechanism of action whereby it interrupts cell signaling pathways that cause replication and proliferation of cancer cells, re-establishes pathways for programmed cell death, or apoptosis, in cancer cells, and modulates the immune response against cancer cells. Genprex's strategy is to develop REQORSA in combination with currently approved therapies and believes that REQORSA's unique attributes position it to provide treatments that improve on these current therapies for patients with NSCLC, SCLC, and possibly other cancers. About The Oncoprex® Delivery System Genprex's ONCOPREX Delivery System is a novel non-viral approach that utilizes lipid-based nanoparticles in a lipoplex form to deliver tumor suppressor genes deleted during the course of cancer development. The platform allows for the intravenous delivery of various tumor suppressor genes, and potentially other genes, to achieve a therapeutic affect without the risk of toxicity often associated with viral delivery systems. Genprex believes this system allows for delivery of a number of cancer-fighting genes, alone or in combination with other cancer therapies, to combat multiple types of cancer. About Genprex, Inc. Genprex, Inc. is a clinical-stage gene therapy company focused on developing life-changing therapies for patients with cancer and diabetes. Genprex's technologies are designed to administer disease-fighting genes to provide new therapies for large patient populations with cancer and diabetes who currently have limited treatment options. Genprex works with world-class institutions and collaborators to develop drug candidates to further its pipeline of gene therapies in order to provide novel treatment approaches. Genprex's oncology program utilizes its systemic, non-viral Oncoprex® Delivery System which encapsulates the gene-expressing plasmids using lipid-based nanoparticles in a lipoplex form. The resultant product is administered intravenously, where it is taken up by tumor cells that then express tumor suppressor proteins that were deficient in the tumor. The Company's lead product candidate, Reqorsa® Immunogene Therapy (quaratusugene ozeplasmid), is being evaluated in three clinical trials as a treatment for NSCLC and SCLC. Each of Genprex's three lung cancer clinical programs has received a Fast Track Designation from the FDA for the treatment of that patient population, and Genprex's SCLC program has received an FDA Orphan Drug Designation. Genprex's diabetes gene therapy approach is comprised of a novel infusion process that uses an AAV vector to deliver Pdx1 and MafA genes directly to the pancreas. In models of Type 1 diabetes, GPX-002 transforms alpha cells in the pancreas into functional beta-like cells, which can produce insulin but may be distinct enough from beta cells to evade the body's immune system. In a similar approach, GPX-002 for Type 2 diabetes, where autoimmunity is not at play, is believed to rejuvenate and replenish exhausted beta cells. Interested investors and shareholders are encouraged to sign up for press releases and industry updates by visiting the Company Website, registering for Email Alerts and by following Genprex on Twitter, Facebook and LinkedIn. Cautionary Language Concerning Forward-Looking Statements Statements contained in this press release regarding matters that are not historical facts are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements are made on the basis of the current beliefs, expectations and assumptions of management, are not guarantees of performance and are subject to significant risks and uncertainty. These forward-looking statements should, therefore, be considered in light of various important factors, including those set forth in Genprex's reports that it files from time to time with the Securities and Exchange Commission and which you should review, including those statements under "Item 1A – Risk Factors" in Genprex's Annual Report on Form 10-K for the year ended December 31, 2023. Because forward-looking statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. Such statements include, but are not limited to, statements regarding: Genprex's ability to advance the clinical development, manufacturing and commercialization of its product candidates in accordance with projected timelines and specifications; the timing and success of Genprex's clinical trials and regulatory approvals; the effect of Genprex's product candidates, alone and in combination with other therapies, on cancer and diabetes; Genprex's future growth and financial status, including Genprex's ability to maintain compliance with the continued listing requirements of The Nasdaq Capital Market and to continue as a going concern and to obtain capital to meet its long-term liquidity needs on acceptable terms, or at all; Genprex's commercial and strategic partnerships, including those with its third party vendors, suppliers and manufacturers and their ability to successfully perform and scale up the manufacture of its product candidates; and Genprex's intellectual property and licenses. These forward-looking statements should not be relied upon as predictions of future events and Genprex cannot assure you that the events or circumstances discussed or reflected in these statements will be achieved or will occur. If such forward-looking statements prove to be inaccurate, the inaccuracy may be material. You should not regard these statements as a representation or warranty by Genprex or any other person that Genprex will achieve its objectives and plans in any specified timeframe, or at all. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this press release. Genprex disclaims any obligation to publicly update or release any revisions to these forward-looking statements, whether as a result of new information, future events or otherwise, after the date of this press release or to reflect the occurrence of unanticipated events, except as required by law. Genprex, Inc. (877) 774-GNPX (4679) GNPX Investor Relations investors@genprex.com GNPX Media Contact Kalyn Dabbs media@genprex.com Company Codes: NASDAQ-NMS:GNPX

NPRL2 Gene Therapy Induces Anti-Tumor Activity in Anti-PD1 Resistant KRAS/STK11 Mutant Non-Small Cell Lung Cancer in a Humanized Mouse Model Provides Additional Preclinical Validation of Oncoprex® Delivery System With Another Tumor Suppressor Gene AUSTIN, Texas, April 2, 2024 /PRNewswire/ --Genprex, Inc. ("Genprex" or the "Company") (NASDAQ: GNPX), a clinical-stage gene therapy company focused on developing life-changing therapies for patients with cancer and diabetes, today announced that its research collaborators have published positive preclinical data for the NPRL2 tumor suppressor gene, utilizing the Company's non-viral Oncoprex® Delivery System, in KRAS/STK11 mutant anti-PD1 resistant non-small cell lung cancer (NSCLC) in a humanized mouse model. NPRL2 is a tumor suppressor gene whose expression is reduced in many cancers including lung, renal, colorectal, glioma, gastric, and hepatocellular carcinoma, and it has been closely correlated with poor clinical outcomes. Genprex's Oncoprex® Delivery System is a novel non-viral approach that utilizes lipid-based nanoparticles in a lipoplex form to deliver tumor suppressor genes deleted during the course of cancer development. The platform allows for the intravenous delivery of various tumor suppressor genes, and potentially other genes, to achieve a therapeutic affect without the risk of toxicity often associated with viral delivery systems. Genprex believes this system allows for delivery of a number of cancer-fighting genes, alone or in combination with other cancer therapies, to combat multiple types of cancer. The manuscript, titled, "NPRL2 gene therapy induces effective anti-tumor immunity in KRAS/STK11 mutant anti-PD1 resistant metastatic non-small cell lung cancer (NSCLC) in a humanized mouse model," was published on the bioRxiv biology preprint server. "These positive preclinical data are very encouraging and support NPRL2 gene therapy as a potential treatment for a sub-group of NSCLC in which patients traditionally are resistant to existing therapies," said Rodney Varner, President, Chairman and Chief Executive Officer at Genprex. "We believe this data could support the potential for a new drug candidate in our pipeline, and it also provides further evidence that the Oncoprex® Delivery System has the ability to be successful using genes other than the TUSC2 gene we are already using in clinical trials with Reqorsa®." The studies evaluated the intravenous injection of NPRL2 gene-loaded cationic lipoplexes (DOTAP-NPRL2) with or without anti-PD1 drugs (pembrolizumab). The studies used a KRAS/STK11 mutant anti-PD1 insensitive cell line, as well as syngeneic mouse LLC2 tumors, which are also anti-PD1 resistant. In both of these mouse models, NPRL2 showed a significantly strong anti-tumor effect whereas anti-PD1 (pembrolizumab) was not effective. The anti-tumor effect was greater in humanized mice than non-humanized mice, suggesting that an immune response contributed to anti-tumor activity. Additionally, a dramatic anti-tumor effect was mediated by NPRL2 treatment with or without a pembrolizumab combination. Bioluminescence imaging on mice showed that 7 out of 10 mice contained an extremely low amount of tumor burden in the NPRL2 treatment group, which was significantly different than in the control or pembrolizumab group. Unlike previous experiments with Reqorsa® Immunogene Therapy (quartusugene ozeplasmid), the Company's lead drug candidate using the TUSC2 tumor suppressor gene, the anti-tumor efficacy of DOTAP-NPRL2 did not involve Natural Killer (NK) cells. The studies also found that tumors with stable NPRL2 expression exhibited significantly slower growth compared to controls. In conclusion, researchers reported that NPRL2 gene therapy induces anti-tumor activity through dendritic cell-mediated antigen presentation and cytotoxic immune cell activation. About Genprex, Inc. Genprex, Inc. is a clinical-stage gene therapy company focused on developing life-changing therapies for patients with cancer and diabetes. Genprex's technologies are designed to administer disease-fighting genes to provide new therapies for large patient populations with cancer and diabetes who currently have limited treatment options. Genprex works with world-class institutions and collaborators to develop drug candidates to further its pipeline of gene therapies in order to provide novel treatment approaches. Genprex's oncology program utilizes its systemic, non-viral Oncoprex® Delivery System which encapsulates the gene-expressing plasmids using lipid-based nanoparticles in a lipoplex form. The resultant product is administered intravenously, where it is taken up by tumor cells that then express tumor suppressor proteins that were deficient in the tumor. The Company's lead product candidate, Reqorsa® Immunogene Therapy (quaratusugene ozeplasmid), is being evaluated in three clinical trials as a treatment for NSCLC and SCLC. Each of Genprex's three lung cancer clinical programs has received a Fast Track Designation from the FDA for the treatment of that patient population, and Genprex's SCLC program has received an FDA Orphan Drug Designation. Genprex's diabetes gene therapy approach is comprised of a novel infusion process that uses an AAV vector to deliver Pdx1 and MafA genes directly to the pancreas. In models of Type 1 diabetes, GPX-002 transforms alpha cells in the pancreas into functional beta-like cells, which can produce insulin but may be distinct enough from beta cells to evade the body's immune system. In a similar approach, GPX-002 for Type 2 diabetes, where autoimmunity is not at play, is believed to rejuvenate and replenish exhausted beta cells. Interested investors and shareholders are encouraged to sign up for press releases and industry updates by visiting the Company Website, registering for Email Alerts and by following Genprex on Twitter, Facebook and LinkedIn. Cautionary Language Concerning Forward-Looking Statements Statements contained in this press release regarding matters that are not historical facts are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements are made on the basis of the current beliefs, expectations and assumptions of management, are not guarantees of performance and are subject to significant risks and uncertainty. These forward-looking statements should, therefore, be considered in light of various important factors, including those set forth in Genprex's reports that it files from time to time with the Securities and Exchange Commission and which you should review, including those statements under "Item 1A – Risk Factors" in Genprex's Annual Report on Form 10-K for the year ended December 31, 2023. Because forward-looking statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. Such statements include, but are not limited to, statements regarding: Genprex's ability to advance the clinical development, manufacturing and commercialization of its product candidates in accordance with projected timelines and specifications; the timing and success of Genprex's clinical trials and regulatory approvals; the effect of Genprex's product candidates, alone and in combination with other therapies, on cancer and diabetes; Genprex's future growth and financial status, including Genprex's ability to maintain compliance with the continued listing requirements of The Nasdaq Capital Market and to continue as a going concern and to obtain capital to meet its long-term liquidity needs on acceptable terms, or at all; Genprex's commercial and strategic partnerships, including those with its third party vendors, suppliers and manufacturers and their ability to successfully perform and scale up the manufacture of its product candidates; and Genprex's intellectual property and licenses. These forward-looking statements should not be relied upon as predictions of future events and Genprex cannot assure you that the events or circumstances discussed or reflected in these statements will be achieved or will occur. If such forward-looking statements prove to be inaccurate, the inaccuracy may be material. You should not regard these statements as a representation or warranty by Genprex or any other person that Genprex will achieve its objectives and plans in any specified timeframe, or at all. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this press release. Genprex disclaims any obligation to publicly update or release any revisions to these forward-looking statements, whether as a result of new information, future events or otherwise, after the date of this press release or to reflect the occurrence of unanticipated events, except as required by law. Genprex, Inc. (877) 774-GNPX (4679) GNPX Investor Relations investors@genprex.com GNPX Media Contact Kalyn Dabbs media@genprex.com Company Codes: NASDAQ-NMS:GNPX