Targeting Neoantigens in Triple Negative Breast Cancer

项目概要/摘要 新抗原已经被我们和其他人鉴定为在免疫治疗的背景下的重要靶点。 检查点阻断疗法、过继细胞疗法和疫苗疗法。我们最近启动了两个阶段 1基于新抗原DNA疫苗的第一代新抗原疫苗在乳腺癌中的临床试验 和合成长肽疫苗平台。在临床前模型中，我们优化了测序和表位， 预测算法的识别和优先排序的新抗原，我们已经利用创新的 技术（CyTOF，单细胞RNA测序），以全面询问免疫反应， 新抗原疫苗接种和其他癌症免疫疗法。我们建议根据这些意见， 进行单独的新抗原DNA疫苗与新抗原DNA疫苗加 新辅助化疗后持续性三阴性乳腺癌（TNBC）患者中的抗PD-L1 化疗总的假设是，增强新抗原特异性T细胞应答可以改善 TNBC的临床结果。将通过完成以下目标来检验这一假设： 具体目标1。检验新抗原疫苗+/-抗PD-L1可诱导和/或增强 新抗原特异性T细胞应答。我们最近启动了一项随机1期临床试验， 新抗原DNA疫苗+/-抗PD-L1治疗新辅助治疗后持续性疾病的TNBC患者 化疗下一代测序和表位预测算法将用于优先排序 新抗原新抗原DNA疫苗将在SCC的GMP工厂设计和生产。 具体目标2：检验靶向肿瘤相关巨噬细胞（TAM）可以增强 TNBC中的新抗原特异性T细胞应答。胚胎来源的组织驻留TAM和 炎性单核细胞衍生TAM抑制TNBC中的抗肿瘤免疫。我们建议将联合收割机 CSF 1/CSF 1 R阻断与CCR 2抑制同时靶向TAM的两种来源， 在两种小鼠乳腺癌模型中的新抗原疫苗接种。肿瘤微环境将被表征 通过CyTOF和单细胞RNA测序。 具体目的3：检验新抗原猿猴Ad载体疫苗“初免”随后是免疫应答的假设。 新抗原DNA疫苗“加强”可增强对乳腺癌新抗原的反应。我们提出 “初免/加强”策略，包括猴重组Ad疫苗“初免”，随后是质粒DNA 疫苗“助推。“这种“初免/加强”新抗原疫苗策略代表了最先进的疫苗策略 更有效地诱导抗肿瘤免疫，并利用WUSM在以下领域的专业知识： 新抗原DNA疫苗和重组Ad载体疫苗。光裂解四聚体分析，CyTOF， 并且将对外周血中的新抗原特异性T细胞进行单细胞RNA测序， 肿瘤微环境，以严格评估新抗原特异性T细胞对疫苗接种的反应。

PROJECT SUMMARY/ABSTRACT Neoantigens have been identified by us and others as important targets of immunotherapy in the context of checkpoint blockade therapy, adoptive cell therapy, and vaccine therapy. We have recently initiated two phase 1 clinical trials of first generation neoantigen vaccines in breast cancer based on the neoantigen DNA vaccine and synthetic long peptide vaccine platforms. In preclinical models, we have optimized sequencing and epitope prediction algorithms for the identification and prioritization of neoantigens, and we have leveraged innovative technologies (CyTOF, single cell RNA sequencing) to comprehensively interrogate the immune response to neoantigen vaccination and other cancer immunotherapies. We propose to build on these observations by performing a randomized phase 1 trial of neoantigen DNA vaccine alone vs. neoantigen DNA vaccine plus anti-PD-L1, in patients with persistent triple negative breast cancer (TNBC) following neoadjuvant chemotherapy. The overall hypothesis is that enhancing neoantigen-specific T cell responses can improve clinical outcomes in TNBC. This hypothesis will be tested by completing the following aims: Specific Aim 1. Test the hypothesis that neoantigen vaccines +/- anti-PD-L1 can induce and/or enhance neoantigen-specific T cell responses. We have recently initiated a randomized phase 1 clinical trial of neoantigen DNA vaccines +/- anti-PD-L1 in TNBC patients with persistent disease following neoadjuvant chemotherapy. Next-generation sequencing and epitope prediction algorithms will be used to prioritize neoantigens. Neoantigen DNA vaccines will be designed and manufactured in the GMP facility at SCC. Specific Aim 2: Test the hypothesis that targeting tumor-associated macrophages (TAM) can enhance neoantigen-specific T cell responses in TNBC. Both embryonically-derived tissue-resident TAM and inflammatory monocyte-derived TAM restrain antitumor immunity in TNBC. We propose to combine CSF1/CSF1R blockade with CCR2 inhibition to simultaneously target both sources of TAM in the context of neoantigen vaccination in two mouse breast cancer models. The tumor microenvironment will be characterized by CyTOF and single cell RNA sequencing. Specific Aim 3: Test the hypothesis that a neoantigen simian Ad vector vaccine "prime" followed by a neoantigen DNA vaccine "boost" can enhance the response to breast cancer neoantigens. We propose a "prime/boost" strategy consisting of a simian recombinant Ad vaccine "prime," followed by a plasmid DNA vaccine "boost." This "prime/boost" neoantigen vaccine strategy represents a state-of-the-art vaccine strategy to more effectively induce antitumor immunity, and leverages expertise at WUSM within the fields of neoantigen DNA vaccines and recombinant Ad vector vaccines. Photocleavable tetramer analysis, CyTOF, and single cell RNA sequencing will be performed on neoantigen-specific T cells in the peripheral blood and the tumor microenvironment to rigorously evaluate the neoantigen-specific T cell response to vaccination.