Preclinical investigation of PI3K inhibition and immune checkpoint blockade combination therapy for treatment of Merkel cell carcinoma using humanized mouse models

使用人源化小鼠模型进行 PI3K 抑制和免疫检查点阻断联合疗法治疗默克尔细胞癌的临床前研究

• 批准号: 10015843
• 负责人: Ling Gao
• 金额: --
• 依托单位: VETERANS HEALTH ADMINISTRATION
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10015843
• 关键词: Affect; Animal Model; Antitumor Response; Attenuated; Biological Markers; Biological Models; Case Study; Caucasians; Cell Line; Cell Proliferation; Cell Survival; Cell physiology; Cells; Clinical; Combination immunotherapy; Combined Modality Therapy; Consensus; Development; Diagnosis; Disease; Event; Failure; Family member; Future; Genetic Engineering; Goals; Growth; Head and Neck Squamous Cell Carcinoma; Health; Healthcare Systems; Heterogeneity; Human; Immune; Immune response; Immune system; Immunotherapy; In Vitro; Incidence; Investigation; Knowledge; Lead; Ligands; Malignant Epithelial Cell; Malignant Neoplasms; Mediating; Merkel cell carcinoma; Methods; Modality; Molecular; Mus; Mutation; Neoplasm Metastasis; PD-1 blockade; PD-1/PD-L1; Pathway interactions; Patients; Pharmaceutical Preparations; Phosphatidylinositide 3-Kinase Inhibitor; Phosphotransferases; Population; Positioning Attribute; Protein Isoforms; Reporting; Research; Resistance; Skin Cancer; Solid Neoplasm; Survival Rate; Testing; Therapeutic; Time; Tissues; Treatment Efficacy; Treatment Protocols; Tumor Immunity; Tumor-infiltrating immune cells; United States Food and Drug Administration; Veterans; Work; Xenograft procedure; advanced disease; anti-PD-1; anti-PD-L1; antitumor effect; base; cancer immunotherapy; clinical translation; clinically relevant; combinatorial; dosage; functional status; high risk; humanized mouse; immune checkpoint blockade; in vivo; indexing; innovation; male; melanoma; molecular targeted therapies; mouse model; neoplastic cell; neuroendocrine cancer; novel; novel therapeutics; pre-clinical; preclinical study; programmed cell death protein 1; response; response biomarker; single-cell RNA sequencing; standard of care; success; targeted treatment; therapeutic target; transcriptome; transcriptome sequencing; treatment response; tumor; tumor growth; tumor heterogeneity; tumor progression; tumor xenograft; tumorigenesis

Merkel cell carcinoma (MCC) is an aggressive skin cancer that has quadrupled in incidence with a dismal five- year survival rate of less than 18% in advanced diseases. MCC disproportionately and predominantly affects Caucasian males older than 65 who are well represented in our Veteran population, especially for those who are deployed to high UV index tropical and subtropical zones and are not well protected due to other survival priorities. Hence, MCC has a growing impact on the VA healthcare system. Currently, there is no Food and Drug Administration (FDA)-approved targeted therapy for MCC. Recently, immunotherapies such as pembrolizumab and avelumab have been FDA-approved for advanced MCC; nevertheless, a significant portion of patients still succumb to their diseases. Thus, there is an urgent clinical need for novel therapeutic strategies for patients who fail out of or are unsuitable for immunotherapy. Aberrant amplification and mutations of PI3K pathway have been detected in up to 80% of MCCs, making it an attractive therapeutic target. This is supported by our clinical success in treating a Stage IV MCC patient with the 1st FDA approved PI3K- inhibitor idelalisib, which elicited a complete clinical response. Furthermore, our preliminary studies demonstrate that copanlisib, the 2nd FDA approved PI3K inhibitor with activity predominantly against PI3K-α/ isoforms, exerts the most potent antitumor growth effects on MCC. Of relevance to this proposal, PI3K inhibition has been reported to enhance cancer immunotherapies. Thus, there is a strong rationale to develop new combinatorial immunotherapy with targeted therapies to boost therapeutic response and efficacy in MCC. Lack of syngeneic/genetically engineered animal models has hampered preclinical studies in MCC. Notably, in our preliminary studies we have successfully established a powerful, clinically relevant model system of MCC xenograft tumors in mice with competent human immune systems. We hypothesize that PI3K inhibition by copanlisib and PD-1 blockade by pembrolizumab will synergistically attenuate MCC tumor growth by inhibiting MCC cell proliferation and survival and enhancing tumor-infiltration of immune cells and their antitumor activities. Furthermore, we have optimized innovative single-cell RNA sequencing (scRNA-seq) methods to examine tumor heterogeneity and transcriptome profile in human MCC cells. Therefore, we are well positioned to pursue the following specific aims: (Aim 1) examine therapeutic efficacy and identify underlying mechanisms of copanlisib and pembrolizumab therapies on MCC xenograft tumor growth in humanized mice, and (Aim 2) identify cellular and molecular mechanisms of MCC tumor-immune interactions and antitumor immunity in response to copanlisib and pembrolizumab treatments. Using our novel MCC humanized mouse models, we will be able to examine, for the first time, tumor-immune response to copanlisib and pembrolizumab under competent human immune system. Importantly, tumor heterogeneity is a critical determinant of therapeutic failure and tumor progression. Recent advancements in scRNA-seq enable us to explore dynamics of tumor and immune cell subpopulations in response to treatments. To achieve our goals, we will utilize state-of-the-art biotechniques to comprehensively analyze the effects of copanlisib and pembrolizumab treatments on tumors and antitumor immunity at tissue, cellular, and molecular levels. We expect that successful completion of the proposed work will result in the following advances: (1) establishment of a novel treatment paradigm for combinatorial therapies in MCC, as well as other cancers that affect our Veterans and their family members such as melanoma and high-risk head and neck squamous cell carcinoma, (2) identification of tumor and immune cell subpopulations that mediate drug response, as well as biomarkers for sensitivity/resistance to copanlisib and/or pembrolizumab treatment, which can lead to future discovery of effective therapeutic strategies. Knowledge gained from the proposed studies will validate and accelerate clinical translation, which will help Veterans who suffer from MCC and cancers for which current immunotherapies are insufficient.

默克尔细胞癌（MCC）是一种侵略性的皮肤癌，在发病率上四倍，五次 晚期疾病的年生存率小于18％。 MCC不成比例，主要影响 高加索男性在65岁以上，他们在我们的资深人口中有很好的代表，尤其是对于那些 部署到高UV指数热带和亚热带区域，由于其他生存而受到良好保护 优先事项。因此，MCC对VA医疗保健系统的影响越来越大。目前，没有食物和药物 给药（FDA） - 批准了针对MCC的靶向治疗。最近，诸如pembrolizumab之类的免疫疗法 Avelumab已被FDA批准为高级MCC；然而，仍然很大一部分患者 屈服于他们的疾病。那是紧迫的临床需求，需要针对那些新的治疗策略 失败或不适合免疫疗法。 PI3K途径的异常扩增和突变已经 在多达80％的MCC中检测到它是一个有吸引力的治疗靶标。这得到了我们的临床支持 成功治疗IV阶段MCC患者的第一个FDA批准的PI3K-抑制剂Idelalisib的成功，这引起了A 完全临床反应。此外，我们的初步研究表明，第二FDA Copanlisib 批准的PI3K抑制剂主要针对PI3K-α/同工型，施加最有效的抗肿瘤 生长对MCC的影响。与该提案相关的是，据报道PI3K抑制可增强癌症 免疫疗法。那是有很强的理由，可以与有针对性的新组合免疫疗法开发 提高MCC治疗反应和效率的疗法。缺乏合理/基因工程动物 模型阻碍了MCC中的临床前研究。值得注意的是，在我们的初步研究中，我们已经成功 建立了具有胜任人类的小鼠MCC型肌肿瘤的强大，临床相关的模型系统 免疫系统。我们假设Copanlisib的PI3K抑制和PD-1通过Pembrolizumab的抑制作用将 通过抑制MCC细胞增殖和生存和增强来协同衰减MCC肿瘤的生长 免疫细胞及其抗肿瘤活性的肿瘤浸润。此外，我们已经优化了创新 单细胞RNA测序（SCRNA-SEQ）方法，用于检查肿瘤异质性和转录组轮廓 人MCC细胞。因此，我们有能力追求以下特定目标：（目标1）检查 治疗效率并确定MCC上Copanlisib和Pembrolizumab疗法的基本机制 人性化小鼠的元素肿瘤生长，（目标2）鉴定MCC的细胞和分子机制 肿瘤免疫相互作用和抗肿瘤免疫学响应Copanlisib和Pembrolizumab治疗。 使用我们新颖的MCC人源化鼠标模型，我们将能够首次检查肿瘤免疫 在有能力的人类免疫系统下对Copanlisib和Pembrolizumab的反应。重要的是，肿瘤 异质性是对治疗衰竭和肿瘤进展的关键确定。最近的进步 SCRNA-SEQ使我们能够探索响应治疗的肿瘤和免疫细胞亚群的动力学。 为了实现我们的目标，我们将利用最先进的生物技术来全面分析 在组织，细胞和分子的肿瘤和抗肿瘤免疫的Copanlisib和Pembrolizumab治疗 水平。我们希望成功完成拟议的工作将导致以下进展：（1） 建立用于MCC组合疗法的新型治疗范式以及其他癌症 影响我们的退伍军人及其家人，例如黑色素瘤和高风险头和颈部鳞状细胞 癌，（2）鉴定介导药物反应的肿瘤和免疫细胞亚群，以及 生物标志物具有对Copanlisib和/或pembrolizumab治疗的敏感性/抗性，这可能导致未来 发现有效的治疗策略。从拟议的研究中获得的知识将验证和 加速临床翻译，这将帮助患有MCC和癌症的退伍军人 免疫疗法不足。