背景:抗程序性死亡-1(PD-1)/抗PD-配体-1(PD-L1)途径抑制是晚期尿路上皮癌(UC)的标准方案;然而,其有限的疗效反映在报告的中等反应率上.本研究探讨了下一代共抑制受体(IRs;淋巴细胞激活基因3(LAG-3),T细胞免疫球蛋白和粘蛋白结构域3(TIM-3),和具有Ig和ITIM结构域的T细胞免疫受体(TIGIT))及其配体(LGs)对PD-(L)1阻断治疗的反应以及UC患者的肿瘤结局。
方法:我们调查了接受PD-(L)1治疗的转移性UC病例(队列1:n=348,队列2:n=89,队列4:n=29)或涉及手术的晚期UC病例(队列3:n=293,队列5:n=90)。我们使用队列1、2和3评估了关于IR和LGs的mRNA表达谱和相应的临床信息。此外,我们使用多重免疫组织化学(mIHC)对来自队列4和5的福尔马林固定石蜡包埋样品阐明了这些靶向标志物的空间特征.生存,差异表达基因,和基因集富集分析进行。对于mIHC,我们还进行了定量分析,以将免疫和肿瘤细胞密度与患者生存相关联.
结果:与TIM-3和TIGIT的表达相比,LAG-3的表达与PD-(L)1阻断的反应性强相关。在高LAG-3水平的肿瘤中,纤维蛋白原样蛋白1(FGL1)的表达增加对PD-(L)1阻断反应和总生存期有显著负效应.此外,高FGL1水平与CD4+调节性T细胞基因特征升高以及CD39和神经纤毛蛋白-1上调相关,两者均提示CD8+T细胞耗尽.mIHC分析显示,与CD8+LAG-3+细胞-肿瘤FGL1+细胞慢的患者相比,CD8+LAG-3+细胞-肿瘤FGL1+细胞慢的患者与生存率呈显著负相关。
结论:LAG-3表达和高FGL1共表达是与免疫抑制背景相关的不良肿瘤结局的重要预测因素。这些发现是产生假设的,需要进一步的机制和临床研究旨在评估UC中的LAG-3/FGL1阻断。
BACKGROUND: Anti-programmed death-1 (PD-1)/anti-PD-ligand-1 (PD-L1) pathway inhibition is a standard regimen for advanced urothelial carcinoma (UC); however, its limited efficacy has been reflected in reported medium response rates. This study explored the role of next-generation coinhibitory receptors (IRs; lymphocyte activation gene 3 (LAG-3), T-cell immunoglobulin and mucin domain 3 (TIM-3), and T-cell immunoreceptor with Ig and ITIM domains (TIGIT)) and their ligands (LGs) in the response to PD-(L)1 blockade therapy and the oncological outcomes in patients with UC.
METHODS: We investigated metastatic UC cases who underwent PD-(L)1 therapy (cohort 1: n=348, cohort 2: n=89, and cohort 4: n=29) or advanced UC cases involving surgery (cohort 3: n=293 and cohort 5: n=90). We assessed the mRNA expression profiles and corresponding clinical information regarding IRs and LGs using cohorts 1, 2, and 3. Additionally, we elucidated the spatial features of these targeted markers using multiplex immunohistochemistry (mIHC) on formalin-fixed paraffin-embedded samples from cohorts 4 and 5. Survival, differential expressed gene, and Gene Set Enrichment analyses were performed. For mIHC, quantitative analyses were also performed to correlate immune and tumor cell densities with patient survival.
RESULTS: LAG-3 expression was strongly associated with the responsiveness of PD-(L)1 blockade compared with the expression of TIM-3 and TIGIT. In tumors with high LAG-3 levels, the increased expression of fibrinogen-like protein 1 (FGL1) had a significantly negative effect on the response to PD-(L)1 blockade and overall survival. Moreover, high FGL1 levels were associated with elevated CD4+ regulatory T-cell gene signatures and the upregulation of CD39 and neuropilin-1, with both indicating CD8+ T-cell exhaustion. mIHC analyses revealed that patients with stromal CD8+LAG-3+cellshigh-tumor FGL1+cellshigh exhibited a significant negative correlation with survival rates compared with those with stromal CD8+LAG-3+cellshigh-tumor FGL1+cellslow.
CONCLUSIONS: LAG-3 expression and high FGL1 coexpression are important predictive factors of adverse oncological outcomes related to the presence of immunosuppressive contextures. These findings are hypothesis-generating, warranting further mechanistic and clinical studies aimed to evaluate LAG-3/FGL1 blockade in UC.