Novel cell therapy approaches for molecularly defined subsets of therapy-resistant melanoma

针对分子定义的难治性黑色素瘤子集的新型细胞治疗方法

• 批准号: 10780289
• 负责人: Christopher Austin Klebanoff
• 金额: $ 50.66万
• 依托单位: SLOAN-KETTERING INST CAN RESEARCH
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-21 至 2028-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10780289
• 关键词: Acute Myelocytic Leukemia; Adaptive Immune System; Adoptive Cell Transfers; Adoptive Transfer; Affinity; Alleles; Antigen Presentation; Antigen Presentation Pathway; Antigens; Binding; Biochemical; Biometry; Blocking Antibodies; Blood; CD4 Positive T Lymphocytes; CD8-Positive T-Lymphocytes; CRISPR screen; Cancer Patient; Cell Therapy; Cell physiology; Cellular immunotherapy; Clinical; Collection; Colorectal Cancer; Complex; Cytolysis; Data; Defect; Epitopes; FDA approved; Frequencies; Genes; Genetic; Genetic Determinism; Genetic Engineering; Genomics; HLA Antigens; HLA-A gene; Histocompatibility Antigens Class I; Immune; Immunotherapy; Knowledge; MHC Class I Genes; Malignant Neoplasms; Mass Spectrum Analysis; Measures; Mediating; Medical; Modeling; Molecular; Mutate; Mutation; Oncogenes; Oncology; Patients; Peptides; Population; Pre-Clinical Model; Protein Isoforms; Recurrence; Resistance; Sampling; Skin Cancer; Solid; Structure; Surface; T cell response; T-Cell Antigen Receptor Specificity; T-Cell Development; T-Cell Receptor; T-Cell Receptor Genes; T-Lymphocyte; Testing; Therapeutic; Time; Tissues; Treatment Failure; Tumor Immunity; Woman; beta-2 Microglobulin; cancer cell; cancer immunotherapy; cell killing; cross immunity; cross reactivity; disorder control; engineered T cells; experience; gene therapy; genome-wide; immune checkpoint; immune checkpoint blockade; immune function; immunogenic; immunogenicity; improved; in vivo evaluation; innovation; melanoma; men; multidisciplinary; neoantigens; neoplastic cell; novel; novel therapeutic intervention; pharmacologic; preservation; response; screening; selective expression; small molecule inhibitor; structural biology; therapeutic target; therapy resistant; translational approach; tumor; tumor immunology

PROJECT SUMMARY/ABSTRACT Melanoma (MEL) is a model malignancy for studying the mechanisms of cancer immunotherapy. Antibodies that block negative regulators of T cell function, termed immune checkpoint blockade (ICB), have transformed the treatment of MEL and other solid cancers. Although some patients have durable disease control, many fail to respond or progress after initially experiencing tumor regression. Therapeutic resistance is enriched in two molecularly defined MEL subtypes. Twenty eight percent of MELs possess activating mutations (Mut) in the driver oncogene NRAS, the second most common Mut RAS isoform. Beyond MEL, Mut NRAS occurs in other prevalent malignancies, including colorectal cancer (CRC). We and others recently discovered that patients with Mut NRAS MEL and CRC have a significantly shorter time to treatment failure. Separately, ~30% of MELs acquire mutations in beta-2-microglobulin (B2M), an essential component of the human leukocyte antigen class I (HLA-I) complex, following ICB progression. Cancers with Mut B2M are intrinsically resistant to CD8+ T cell killing. Thus, two major gaps in knowledge that limit the potential of immunotherapy in MEL and other common cancers include: (1) identification of immunogenic antigens expressed by Mut NRAS tumors, and (2) therapeutic strategies to overcome genetic loss of HLA-I presentation. We hypothesize that cancers with Mut NRAS or Mut B2M can be therapeutically targeted using T cell receptor (TCR)-based immunotherapies. In support of our hypothesis, we discovered using a mass spectrometry (MS) screen that the three most common NRAS hotspot substitutions generate shared (or “public”) neoantigens (NeoAgs) presented by a prevalent HLA allele. Using a unique collection of biospecimens from patients who express an NRAS public NeoAg, we generated T cells specific for these epitopes, retrieved their TCR gene sequences, and transferred public NeoAg reactivity to polyclonal T cells. These results confirm the immunogenicity of screen-identified NRAS public NeoAgs and enable the development of TCR-based therapies. We further discovered that a significant proportion of MELs undergo direct killing by T cells that express an HLA class II (HLA-II) restricted TCR. Using a genome-scale CRISPR screen, we found that cancer eradication is preserved when B2M and other HLA-I genes are disrupted. Building on these preliminary data, we propose in Aim 1 to develop a novel therapeutic approach for cancers expressing an NRAS public NeoAg using TCR genetic engineering and adoptive cell transfer. In Aim 2, we will study the physical mechanisms underlying NRAS public NeoAg TCR specificity, including the unique capacity of some TCRs to accommodate multiple hotspot substitutions. In Aim 3, we will define the molecular basis for direct cancer cell killing by HLA class II-restricted TCRs and test combinations to enhance the antitumor efficacy of adoptively transferred CD4+ T cells. By completing these aims, we will develop novel, mechanism-based cellular immunotherapies for Mut NRAS and HLA-I deficient cancers.

项目总结/摘要 黑色素瘤（Melanoma，MEL）是研究肿瘤免疫治疗机制的模型肿瘤。抗体 阻断T细胞功能的负调节因子，称为免疫检查点阻断（ICB）， MEL和其他实体癌的治疗。虽然有些病人的疾病得到了持久的控制，但许多人失败了。 在最初经历肿瘤消退后的反应或进展。治疗性耐药性集中在两个方面 分子定义的MEL亚型。28%的MEL具有激活突变（Mut）， 驱动癌基因NRAS，第二常见的Mut RAS亚型。除了MEL之外，Mut NRAS还发生在其他地方 流行的恶性肿瘤，包括结直肠癌（CRC）。我们和其他人最近发现，患者 Mut NRAS MEL和CRC的治疗失败时间显著缩短。另外，约30%的MEL 获得β 2-微球蛋白（B2 M）突变，B2 M是人类白细胞抗原的重要成分 I类（HLA-I）复合物，ICB进展后。携带Mut B2 M的癌症对CD 8 + T具有内在抗性 细胞杀伤因此，限制MEL和其他免疫疗法潜力的两个主要知识缺口是： 常见的癌症包括：（1）鉴定由Mut NRAS肿瘤表达的免疫原性抗原，和（2） 克服HLA-I呈递的遗传丢失的治疗策略。我们假设， NRAS或Mut B2 M可以使用基于T细胞受体（TCR）的免疫疗法进行治疗靶向。在 支持我们的假设，我们发现使用质谱（MS）屏幕，三个最常见的 NRAS热点取代产生由流行HLA呈递的共享（或“公共”）新抗原（NeoAg）， 等位基因使用来自表达NRAS公共NeoAg的患者的独特生物标本集合，我们 产生对这些表位特异性的T细胞，检索它们的TCR基因序列，并将其转移到公共 NeoAg对多克隆T细胞的反应性。这些结果证实了筛选鉴定的NRAS的免疫原性 公开的NeoAg，并使基于TCR的疗法的开发成为可能。我们进一步发现， 一部分MEL经历表达HLA II类（HLA-II）限制性TCR的T细胞的直接杀伤。使用 在基因组规模的CRISPR筛查中，我们发现当B2 M和其他HLA-I 基因被破坏。在这些初步数据的基础上，我们在目标1中提出开发一种新的治疗药物， 使用TCR基因工程和过继细胞用于表达NRAS公共NeoAg的癌症的方法 转移在目标2中，我们将研究NRAS公共NeoAg TCR特异性的物理机制， 包括一些TCR适应多个热点置换的独特能力。在目标3中，我们 定义HLA II类限制性TCR直接杀伤癌细胞的分子基础，并测试组合， 增强过继转移的CD 4 + T细胞的抗肿瘤功效。通过实现这些目标，我们将 为Mut NRAS和HLA-I缺陷型癌症开发新的、基于机制的细胞免疫疗法。