Enhancing TIL populations and immunotherapy efficacy in melanoma by modulating fucosylation

项目摘要/摘要 我们的免疫系统对于识别和抑制体内的癌症至关重要。不幸的是，黑色素瘤， 最致命的皮肤癌之一，可以与免疫细胞相互作用并使其失活。最有效的方案之一 抗黑色素瘤疗法是指重新激活或“训练”免疫系统的抗肿瘤活性的免疫疗法。 细胞。然而，目前免疫疗法的有效性仅限于30%左右的患者。尽管 潜在的原因尚不清楚，患者缺乏反应性与渗透不足有关 由免疫细胞引起的肿瘤。因此，旨在阐明黑色素瘤的研究：免疫相互作用和增加 为了改善免疫治疗，需要肿瘤的免疫渗透。 我们发现了一种潜在的提高免疫疗法疗效的方法，即通过促进 黑色素瘤免疫细胞用抑制肿瘤的植物糖L-岩藻糖。在一个名为 岩藻糖基化时，细胞使用L岩藻糖修饰蛋白质，影响其成熟/功能。我们发现 在人类黑色素瘤进展过程中，岩藻糖基化通常会减少，这促使我们测试是否增加L- 黑色素瘤中岩藻糖/岩藻糖基化水平可产生有益于治疗的效果。简单地给L-岩藻糖喂食 携带黑色素瘤的小鼠可将肿瘤生长和转移减少50%(Liu等人。SCI信号2015)。 有趣的是，这些较小的肿瘤含有的肿瘤浸润性淋巴细胞(TIL)是肿瘤的10-50倍 来自没有喂食L岩藻糖的小鼠。从基因上增加黑色素瘤细胞的岩藻糖基化也会产生同样的效果， 提示黑色素瘤岩藻糖基化可触发抗肿瘤免疫。我们测定了CD4+/CD25-T细胞 对L-岩藻糖激活的TIL的募集至关重要，包括CD8+T、NK和DC抑制肿瘤 成长。我们鉴定了免疫调节蛋白HLA-DRB1是岩藻糖基化的，它的表达对 TIL募集/肿瘤抑制，提示我们的假设是HLA-DRB1的岩藻糖基化触发 CD4+/CD25-T细胞介导的TIL募集和对黑色素瘤的抑制然而，岩藻糖化如何 调节人类白细胞抗原-DRB1以介导抗黑色素瘤免疫，如果这些作用是由于肿瘤增加所致 免疫原性，CD_4~+/CD_(25)-T细胞功能，或两者兼而有之，以及L岩藻糖/岩藻糖基化是否能加强免疫治疗 疗效或对预后的作用尚不清楚。我们提出了3个特定目标(SA)来检验我们的假设，并 回答以下问题： ·SA1：确定岩藻糖化如何调节人类白细胞抗原-DRB1的定位和免疫功能 ·SA2：确定全身岩藻糖化如何影响CD4+/CD25-T细胞生物学。 ·sA3：确定L-岩藻糖/岩藻糖基化是否增强抗PD1/TIL治疗并预测患者预后 我们的目标是提供对黑色素瘤的关键生物学/机械学见解：免疫相互作用，这将 为制定强化的、基于岩藻糖基化的患者分层和治疗策略奠定基础。

PROJECT SUMMARY/ABSTRACT Our immune system is crucial for recognizing and suppressing cancers in the body. Unfortunately, melanomas, one of the most lethal skin cancers, can interact with and inactivate immune cells. Among the most effective anti-melanoma therapies are immunotherapies that reactivate or “train” the anti-tumor activities of immune cells. However, the effectiveness of immunotherapies is currently limited to ~30% of patients. Although the underlying causes are unclear, lack of responsiveness in patients is associated with insufficient infiltration of tumors by immune cells. Thus, studies aimed at elucidating melanoma:immune interactions and increasing the immune infiltration of tumors are required to improve immunotherapies. We discovered a potential way to increase the efficacy of immunotherapies by boosting infiltration of melanomas with tumor-suppressing immune cells using the plant sugar L-fucose. In a process called fucosylation, cells used L-fucose to modify proteins, affecting their maturation/function. We found that fucosylation is generally reduced during melanoma progression in humans, prompting us to test if increasing L- fucose/fucosylation levels in melanomas elicits therapeutically beneficial effects. Simply feeding L-fucose to melanoma-bearing mice reduces tumor growth and metastasis by >50% (Lau et al. Sci Signal 2015). Intriguingly, those smaller tumors contain 10-50 times more tumor-infiltrating lymphocytes (“TIL”) than tumors from mice not fed L-fucose. Genetically increasing the fucosylation of melanoma cells elicits the same effects, suggesting that melanoma fucosylation triggers anti-tumor immunity. We determined that CD4+/CD25- T cells are crucial for L-fucose-triggered recruitment of TILs including CD8+ T, NK, and DCs that suppress tumor growth. We identified the immune-regulating protein HLA-DRB1 as fucosylated, and its expression is crucial for TIL recruitment/tumor suppression, prompting our hypothesis that fucosylation of HLA-DRB1 triggers CD4+/CD25- T cell-mediated TIL recruitment and suppression of melanoma. However, how fucosylation regulates HLA-DRB1 to mediate anti-melanoma immunity, if those effects are due to increased tumor immunogenicity, CD4+/CD25- T cell function, or both, and if L-fucose/fucosylation can enhance immunotherapy efficacy or have prognostic utility is not known. We propose 3 Specific Aims (SAs) to test our hypothesis and address these questions: ·SA1: Determine how fucosylation regulates the localization and immune function of HLA-DRB1 ·SA2: Determine how systemic fucosylation affects CD4+/CD25- T cell biology. ·SA3: Determine if L-fucose/fucosylation enhances anti-PD1/TIL therapy and predicts patient prognosis Our goal is to provide key biological/mechanistic insights into melanoma:immune interactions, which will establish a basis for developing enhanced, fucosylation-based patient stratification and treatment strategies.