Imaging tumor and T cell responses to metabolic and immune modulation therapy

项目概要/摘要 项目的目的。该应用程序侧重于使用成像来更好地理解、反转和 监测侵袭性/转移性乳腺癌小鼠模型的免疫抑制和代谢。高 LDH-A 和单羧酸转运蛋白 1 和 4（MCT-1 和 MCT-4）与预后不良有关， 和更大的转移潜力。基于 GEO 和 MSKCC cBio Portal 的临床分析： i) 肿瘤 随着乳酸代谢相关基因表达的增加，攻击性更强，且攻击性较差。 生存，ii) 糖酵解基因的表达与免疫相关基因之间存在负相关 基因。这些数据支持我们的假设：肿瘤糖酵解率高导致肿瘤富含乳酸 排除 T 细胞的微环境 (TME)，导致更具侵袭性的肿瘤，并倾向于 形成转移。我们进一步假设，用代谢抑制剂逆转 T 细胞排斥将 使对检查点阻断（CTLA-4、PD-1）免疫调节有抵抗力的肿瘤成为 由于肿瘤微环境中 T 细胞的重新增殖，对治疗产生反应。 在这里，我们建议使用多模态成像来探索代谢和免疫的机制 调节疗法逆转临床相关小鼠细胞毒性 T 细胞的限制和失活 侵袭性乳腺癌模型。我们计划：1）表征肿瘤乳酸和 T 细胞的体内变化 LDH-A 和 MCT-1/4 抑制期间的浸润； 2) 评估对单一辅助剂和新辅助剂的反应 和联合治疗（代谢抑制和体内“检查点”阻断）； 3) 验证成像 通过使用离体评估糖酵解生物标志物和 T 细胞浸润之间的相关性来获得结果 免疫荧光 (IF)、免疫组织化学 (IHC) 和荧光辅助细胞分选 (FACS)；和 4) 评估临床转化的潜力。转化目标有两个：1）诱导初级回归 和转移性乳腺癌，通过增加肿瘤渗透和细胞毒性 T 细胞的效应功能，2) 通过非侵入性成像监测治疗反应。 实验策略。我们已经建立了几种侵袭性乳腺癌免疫小鼠模型 有能力的宿主动物。在目标 1 中，体外和体内研究将确定肿瘤细胞代谢如何影响 T 细胞功能，并确定优化 T 细胞再增殖的幅度和时间的“治疗窗口” LDH 和 MCT 药理学抑制后侵袭性小鼠乳腺肿瘤的研究。在目标 2 中，代谢和 免疫 PET 成像将监测 TME 的变化（由抗 LDH 和抗 MCT 治疗引起） 影响T细胞浸润和功能。基于目标 1 和 2 研究，“优化的”乳酸抑制治疗 策略（在目标 1 和 2 中建立）将与免疫检查点封锁（抗 PD1 和抗 CTLA4）并在目标 3 中进行评估。成像将用于定量肿瘤乳酸，即 13C-丙酮酸超极化为乳酸、糖酵解（反映在 FDG 摄取中）和 CD8 T 细胞的运输。

PROJECT SUMMARY/ABSTRACT Purpose of the project. This application focuses on the use of imaging to better understand, reverse, and monitor immune suppression and metabolism in murine models of aggressive/metastatic breast cancer. High LDH-A and monocarboxylate transporters 1 and 4 (MCT-1 and MCT-4) have been linked to poor prognosis, and greater metastatic potential. Based on clinical analyses of GEO and MSKCC’s cBio Portal: i) tumors with increased expression of genes involved in lactate metabolism are more aggressive and have poor survival, and ii) there is an inverse correlation between the expression of glycolysis genes and immune-related genes. These data support our hypothesis: that high rates of tumor glycolysis leads to a lactic acid-rich tumor microenvironment (TME) with the exclusion of T cells, resulting in more aggressive tumors with a propensity to form metastases. We further hypothesize that reversal of the T cell exclusion with metabolic inhibitors will render tumors that are resistant to immune modulation with checkpoint blockade (CTLA-4, PD-1) to be responsive to the treatment, due to repopulation of T cells within the tumor microenvironment. Here, we propose to use multimodal imaging to explore the mechanisms by which metabolic and immune modulation therapy reverse the restriction and inactivation of cytotoxic T cells in clinically relevant murine models of aggressive breast cancer. We plan to: 1) characterize in vivo changes in tumor lactate and T cell infiltration during LDH-A and MCT-1/4 inhibition; 2) evaluate the responses to adjuvant and neo-adjuvant single and combination therapy (metabolic inhibition and “checkpoint” blockade in vivo); 3) validate the imaging results by assessing correlations between glycolytic biomarkers and T cell infiltration using ex vivo immunofluorescence (IF), immunohistochemistry (IHC), and fluorescence-assisted cell sorting (FACS); and 4) assess the potential for clinical translation. The translational goal is two-fold: 1) to induce regression in primary and metastatic breast cancer, by increasing tumor penetration and effector function of cytotoxic T cells, and 2) to monitor treatment response by non-invasive imaging. Experimental Strategy. We have established several murine models of aggressive breast cancer in immune competent host animals. In Aim 1, in vitro and in vivo studies will define how tumor-cell metabolism affects T cell function, and identify a “therapeutic window” for optimizing the magnitude and timing of T cell repopulation of aggressive murine breast tumors following LDH and MCT pharmacologic inhibition. In Aim 2, metabolic and immune-PET imaging will monitor how changes in the TME (induced by anti-LDH and anti-MCT treatment) affect T cell infiltration and function. Based on Aim 1 and 2 studies, an “optimized” lactate inhibition treatment strategy (established in Aims 1 and 2) will be combined with immune checkpoint blockade (anti-PD1 and anti- CTLA4) and assessed in Aim 3. Imaging will be used to quantitate tumor lactate, the conversion of hyperpolarized 13C-pyruvate to lactate, glycolysis (reflected in FDG uptake) and the trafficking of CD8+ T cells.