Defining immune footprint in tumor microenvironment following high salt synergized inflammatory cytokine mediated breast cancer progression

总结 肿瘤微环境中的慢性炎症环境和受损的 T 细胞免疫监视是 表明在癌症进展和转移中起决定性作用。尽管各种免疫效应物 细胞被招募到肿瘤部位，它们的抗肿瘤功能响应于衍生的信号而下调 来自肿瘤微环境。然而，该机制的精确分子信号仍然很差 特点。我们的初步研究表明，刺激初始人类 CD4 T 细胞和 高 NaCl 浓度 (0.2 M) 的单核细胞对 IL-17 产生时间依赖性双峰效应 分泌，最初增加（1-3 天），随后 IL-17 分泌减少（5-7 天），然后 抗炎IL-10分泌增加。暴露于高盐后 IL-17 的后期下降 伴随着免疫抑制 Tregs (CD4 Foxp3 ) 和 MΦ2 样的增强激活 巨噬细胞，以及 CD4 T 中免疫耗竭标志物（CTLA4、PD1、Tim3、LAG3）的上调 细胞。因此，我们假设肿瘤微环境中的高盐浓度与 IL-17 的调节，导致肿瘤生长并伴有免疫耗竭和免疫抑制反应。 这些事件导致晚期效应器免疫消除功能失调，最终加剧癌症 进展和转移。使用小鼠乳腺癌模型，给小鼠喂食不同盐的饮食 内容中，我们将利用先进的钠（Na23）-MRI和免疫学技术来检验这一假设 具有以下两个具体目标：（1）定义和表征对功能变化的时间影响 浸润性 Treg（CD4 FoxP3 IL-10 T 细胞）、Th17（CD4 IL-17 T 细胞）和巨噬细胞（MΦ1/MΦ2 开关）导致乳腺癌进展； （2）明确免疫检查点抑制剂CTLA4的作用 和 PD1 mAb，与检查点抑制剂联合治疗相比，在高盐介导的肿瘤进展中 在两种乳腺癌小鼠模型中采用低盐饮食。我们预计这项研究的结果将 帮助描述高盐介导的免疫反应功能障碍的分子机制 肿瘤微环境与降低盐组织水平具有潜在的临床转化相关性 接受免疫检查点抑制剂治疗的患者。 ！

Summary Chronic inflammatory milieu and compromised T-cell immune-surveillance in the tumor microenvironment is suggested to play a decisive role in cancer progression and metastasis. Although various immune effector cells are recruited to the tumor site, their anti-tumor function is down-regulated in response to signals derived from the tumor microenvironment. However, the precise molecular signals for this mechanism remain poorly characterized. Our preliminary studies have demonstrated that stimulation of naive human CD4+T cells and monocytes with high NaCl concentrations (0.2 M) resulted in a temporal-dependent bimodal effect on IL-17 secretion, with an initial increase (1-3 days), followed by a decrease in IL-17 secretion (5-7 days), and an increase in anti- inflammatory IL-10 secretion. This later phase decrease in IL-17 after exposure to high salt is accompanied by enhanced activation of immune-suppressive Tregs(CD4+Foxp3+) and MΦ2-like macrophages, along with up-regulation of immune exhaustion markers (CTLA4, PD1, Tim3, LAG3) in CD4+T cells. Thus, we hypothesize that high-salt concentration in the tumor microenvironment is linked to modulation of IL-17, resulting in tumor growth with immune-exhaustion and immune-suppression responses. These events lead to a dysfunctional late phase effector immune-elimination, culminating to enhance cancer progression and metastasis. Using murine breast cancer models where mice are fed a diet with varying salt content, we will utilize advanced sodium(Na23)-MRI and immunological techniques to test this hypothesis with the following two specific aims: (1) Define and characterize the temporal effect on the functional changes in infiltrating Treg (CD4+FoxP3+IL-10+T cells), Th17(CD4+IL-17+T cells), and macrophages (MΦ1/MΦ2 switch) leading to breast cancer progression; (2) Define the role of immune check-point inhibitors, CTLA4 and PD1 mAb, in high salt-mediated tumor progression compared to checkpoint inhibitor therapy combined with a low-salt diet in two mouse models of breast cancer. We envision that the outcomes of this study will help delineate the molecular mechanisms involved in high salt-mediated dysfunction of immune responses in the tumor microenvironment with a potential clinical translational relevance of lowering salt tissue levels in patients undergoing treatment with immune-check point inhibitors. !