Quantitative assessment of pre-metastatic immune subversion as a risk factor for melanoma relapse

项目摘要/摘要 对于实体肿瘤最先发生的免疫学悖论的理解存在一个根本的鸿沟 通过淋巴通道转移到免疫功能丰富的淋巴结。在这个过程中，免疫 监测被禁用，最终允许转移扩散到它应该在的准确位置 首先消除的是肿瘤引流的前哨淋巴结(SLN)。虽然值得注意的是预测，但很明显 仅有SLN的转移状态不足以确定患者的风险或复发。因此， 了解肿瘤介导的区域性慢性化过程的机制 免疫抑制，通常被称为转移前巢(PMN)在SLN中的形成将 开发改进的预后和治疗工具以检测和逆转癌症的重要见解 在转移性进展的自然病程中早期扩散。我们的长远目标是发展 能够克服SLN PMN的免疫损害从而干扰的治疗策略 癌症转移的第一阶段。因此，当前工作的目标是机械化地 探讨原发肿瘤淋巴流出的亚细胞成分直接流出的过程 调节PMN的形成。中心假说认为，在实体瘤中，亚细胞介质来源于 来自原发肿瘤的微环境主动地通过淋巴管运输，并在货物中起依赖作用 方法在肿瘤引流的SLN中建立PMN。这一假设是在以下基础上提出的 申请人实验室产生的初步数据；即发现和表征 具有调节能力的人淋巴管外囊泡(L-EV) 免疫功能。基本原理认为，在阐明定义PMN的因素和特征时 在SLN的形成中，所获得的知识将是重要的，因为它将识别组织病理学生物标记物 可能有助于患者风险分层，超出SLN中黑色素瘤细胞的存在。以Strong为指导 初步数据，这一假说将在两个特定的目的进行检验：1)确定淋巴循环的机制 在转移前SLN中，亚细胞因子促进免疫功能障碍的程度超出了已发现的水平(即 S100A9)；2)评估这些免疫调节因子在预测复发风险中的预后作用 通过考虑全面的、交互的细胞景观来定义免疫学上的 受威胁的SLN。这种方法是创新的，因为它将使用机制驱动的模型来识别亚细胞 来自以前未知的生物流体，人淋巴(目标1)的因子，由一种新的， 多重生物标志物成像方法定量观察SLN免疫状况 和空间保存的方式，以最终将预测特征转换成临床可服从的平台 (目标2)。这些发现将导致对有复发风险和需要治疗的早期患者的精确定义。 更早的干预。

PROJECT SUMMARY/ABSTRACT There is a fundamental gap in understanding the immunological paradox by which solid tumors first metastasize via lymphatic channels into the immune-rich lymph node. During this process, immune surveillance is disabled, ultimately allowing metastatic dissemination to the precise location where it should be first eliminated—the tumor-draining, sentinel lymph node (SLN). While notably prognostic, it is clear the metastatic status of the SLN alone is not sufficient in determining patient’s risk or relapse. Therefore, understanding the mechanisms underlining this chronic process of tumor mediated regional immunosuppression, commonly referred to as pre-metastatic niche (PMN) formation in the SLN will lend significant insights for developing improved prognostic and therapeutic tools to detect and reverse cancer dissemination early in the natural history of metastatic progression. Our long term goal is to develop therapeutic strategies capable of overcoming the immune compromise of the SLN PMN and thereby disrupt the first stage of cancer metastasis. Therefore, the objective of the current work is to mechanistically interrogate the process by which the subcellular component of the primary tumor lymphatic effluent directly mediates PMN formation. The central hypothesis proposes that in solid tumors, subcellular mediators derived from the primary tumor microenvironment actively traffic through the lymphatics and in a cargo-dependent manner create a PMN in the tumor-draining SLN. This hypothesis has been formulated on the basis of preliminary data produced in the applicant’s laboratory; namely the discovery and characterization of human lymphatic extracellular vesicles (L-EV) which have a demonstrated capacity to modulate immune function. The rationale asserts that in elucidating the factors and signatures that define PMN formation in the SLN, the knowledge gained will be significant as it will identify histopathologic biomarkers that could aid in patient risk stratification beyond the presence of melanoma cells in the SLN. Guided by strong preliminary data, this hypothesis will be tested in two specific aims: 1) identify mechanisms whereby lymphatic subcellular factors promote immune dysfunction in the pre-metastatic SLN beyond those already identified (i.e. S100A9); 2) evaluate the prognostic utility of these immune-modulating factors in predicting risk of recurrence by considering the comprehensive, interactive cellular landscape that defines the immunologically compromised SLN. The approach is innovative as it will use a mechanism-driven model to identify subcellular factors from a previously uncharacterized biological fluid, human lymph (Aim 1), complemented by a novel, multiplexed biomarker imaging approach in order to survey the SLN immunological landscape in a quantitative and spatially preserved manner to ultimately translate predictive features into clinically amenable platforms (Aim 2). Such findings will result in a refined definition of early-stage patients at risk of relapse and in need of earlier interventions.