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: 10454765
• 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/10454765
• 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; 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; military veteran; molecular targeted therapies; mouse model; neoplastic cell; neuroendocrine cancer; novel; novel therapeutic intervention; pembrolizumab; pre-clinical; preclinical study; programmed cell death protein 1; response; response biomarker; single-cell RNA sequencing; standard of care; success; targeted treatment; therapeutic target; therapeutically effective; 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) 是一种侵袭性皮肤癌，其发病率已翻了四倍，令人沮丧的五- 晚期疾病的年生存率低于 18%。 65 岁以上的白人男性在我们的退伍军人群体中占有很大比例，尤其是那些 部署在高紫外线指数热带和亚热带地区，由于其他生存原因而没有得到很好的保护 因此，MCC 对 VA 医疗保健系统的影响越来越大，目前没有食品和药品。 最近，FDA 批准了针对 MCC 的靶向治疗，例如派姆单抗 (pembrolizumab)。 和 avelumab 已获得 FDA 批准用于治疗晚期 MCC；尽管如此，仍有很大一部分患者仍接受治疗； 因此，临床上迫切需要针对这些患者的新治疗策略。 PI3K 通路的异常扩增和突变已导致免疫治疗失败或不适合。 在高达 80% 的 MCC 中检测到，使其成为有吸引力的治疗靶点，这一点得到了我们的临床支持。 FDA 批准的第一个 PI3K- 抑制剂 idelalisib 成功治疗了 IV 期 MCC 患者，该药物引起了 此外，我们的初步研究表明，copanlisib是第二个FDA药物。 经批准的 PI3K 抑制剂，主要针对 PI3K-α/ 亚型，发挥最有效的抗肿瘤作用 与该提议相关的是，PI3K 抑制已被报道可增强癌症的发生。 因此，开发新的靶向组合免疫疗法是有充分理由的。 缺乏同基因/基因工程动物来提高 MCC 的治疗反应和疗效。 模型阻碍了 MCC 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。 在具有人类能力的小鼠中建立了强大的、临床相关的 MCC 异种移植肿瘤模型系统 我们追求 copanlisib 的 PI3K 抑制和 pembrolizumab 的 PD-1 阻断作用。 通过抑制 MCC 细胞增殖和存活并增强 MCC 肿瘤生长，协同减弱 MCC 肿瘤生长 此外，我们还优化了免疫细胞的肿瘤浸润及其抗肿瘤活性。 单细胞 RNA 测序 (scRNA-seq) 方法可检查肿瘤异质性和转录组谱 因此，我们有能力实现以下具体目标：（目标 1）检查。 copanlisib 和 pembrolizumab 治疗 MCC 的疗效并确定其潜在机制 人源化小鼠中异种移植肿瘤的生长，以及（目标 2）确定 MCC 的细胞和分子机制 copanlisib 和 pembrolizumab 治疗反应的肿瘤免疫相互作用和抗肿瘤免疫。 使用我们的新型 MCC 人源化小鼠模型，我们将能够首次检查肿瘤免疫 重要的是，在有效的人类免疫系统下对 copanlisib 和 pembrolizumab 的反应。 异质性是治疗失败和肿瘤进展的关键决定因素。 scRNA-seq 使我们能够探索肿瘤和免疫细胞亚群对治疗的反应动态。 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 copanlisib 和 pembrolizumab 对肿瘤的治疗以及组织、细胞和分子的抗肿瘤免疫 我们期望成功完成拟议工作将取得以下进展：（1） 为 MCC 以及其他癌症的组合疗法建立新的治疗模式 影响我们的退伍军人及其家人，例如黑色素瘤和高风险头颈部鳞状细胞 癌症，(2) 鉴定介导药物反应的肿瘤和免疫细胞亚群，以及 对 copanlisib 和/或 pembrolizumab 治疗敏感/耐药的生物标志物，这可能会导致未来 从拟议的研究中获得的知识将验证和发现有效的治疗策略。 加速临床转化，这将帮助患有 MCC 和当前癌症的退伍军人 免疫疗法还不够。