The prostanoid EP4 receptor is one of the key receptors associated with inflammatory mediator PGE2-elicited immunosuppression in the tumor microenvironment. Blockade of EP4 signaling to enhance immunity-mediated tumor elimination has recently emerged as a promising strategy for cancer immunotherapy. In our efforts to discover novel subtype-selective EP4 antagonists, we designed and synthesized a class of 1H-1,2,3-triazole-based ligands that display low nanomolar antagonism activity toward the human EP4 receptor and excellent subtype selectivity. The most promising compound 59 exhibits single-digit nanomolar potency in the EP4 calcium flux and cAMP-response element reporter assays and effectively suppresses the expression of multiple immunosuppression-related genes in macrophage cells. On the basis of its favorable ADMET properties, compound 59 was chosen for further in vivo biological evaluation. Oral administration of compound 59 significantly inhibited tumor growth in the mouse CT26 colon carcinoma model accompanied by enhanced infiltration of cytotoxic T lymphocytes in the tumor tissue.

中文翻译：

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发现和表征1H-1,2,3-三唑衍生物作为新型前列腺素EP4受体拮抗剂，用于癌症免疫治疗。

前列腺素EP4受体是与炎症介质PGE 2在肿瘤微环境中引起的免疫抑制相关的关键受体之一。近年来，EP4信号传导的阻断增强了免疫介导的肿瘤消除作用，已成为一种有前景的癌症免疫疗法策略。在我们努力发现新型亚型选择性EP4拮抗剂的过程中，我们设计并合成了一类基于1H-1,2,3-三唑的配体，这些配体对人EP4受体具有低纳摩尔拮抗作用，并且具有出色的亚型选择性。最有前途的化合物59在EP4钙流量和cAMP响应元件报告基因分析中表现出个位数的纳摩尔浓度，并有效抑制巨噬细胞中多个免疫抑制相关基因的表达。基于其良好的ADMET性能，选择化合物59用于进一步的体内生物学评估。口服给予化合物59可显着抑制小鼠CT26结肠癌模型中的肿瘤生长，并伴随肿瘤组织中细胞毒性T淋巴细胞的浸润增强。