PO.CL06.01 · 临床研究
空间分析确定肿瘤相关基质富集和MIF为原发性尤因肉瘤中潜在的免疫治疗靶点
Spatial profiling identifies tumor-associated stroma enrichment and MIF as potential immunotherapy targets in primary Ewing sarcomas
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
目的：迄今为止，免疫治疗在尤因肉瘤（EwS）中的反应率一直很低。绝大多数转移性或复发性EwS患儿尽管接受了当前的强化多模式治疗仍然死亡。肿瘤免疫微环境（TME）在癌症的存活和进展中起着至关重要的作用，与耐药性和免疫逃逸有关。然而，人们对EwS的TME缺乏了解。尽管近期对EwS和免疫细胞的单细胞RNA测序揭示了一个具有EwS中不同免疫细胞群亚群的异质性转录图景，但对EwS的TME的空间组织和空间微环境生态位却知之甚少。
方法：我们对16个来自局限性EwS（L-EwS）或转移性EwS（M-EwS）患者的初治原发性EwS肿瘤活检样本进行了空间转录组学（ST）分析，并辅以高维空间蛋白质组学分析。
结果：整合分析揭示了肿瘤间和肿瘤内的异质性。我们在转录层面推断了肿瘤的基质区域，并注意到L-EwS的肿瘤比M-EwS具有显著更多的基质特征（p值<2.2e-16）。使用Hallmark基因集的基因集富集分析显示，L-EwS肿瘤富集了上皮间质转化（EMT）和炎症特征（校正p值<0.05），而M-EwS肿瘤富集了增殖特征（校正p值<0.05）。我们确定了一组在L-EwS中富集的46个独特基因，这些基因与EMT标志通路中的基因重叠，主要是细胞外基质相关（ECM-r）基因，如COL3A1、COL1A2、ITGB1、MMP2、ACTA2、TNC、TGFB1。这些ECM-r基因在空间上与各个肿瘤的基质区域重叠。通过空间配体-受体分析，我们表明基质富集区域含有独特的细胞外基质相关细胞因子、免疫招募和促炎微环境信号，提示EwS基质可能通过充当免疫招募中心而发挥抗肿瘤作用。所有EwS肿瘤均表达促肿瘤发生的MIF-CD74免疫信号连接，提示一种潜在的免疫逃避机制。
结论：与M-EwS相比，L-EwS肿瘤富集了ECM和ECM相关的微环境信号。空间细胞微环境信号揭示了肿瘤相关基质潜在的免疫招募作用，我们的发现为EwS的TME提供了空间层面的洞察，并为将MIF作为EwS免疫治疗潜在靶点进行临床前研究提供了理论依据。
查看英文原文 English abstract
Objective: To date, the response rate of immunotherapy in Ewing sarcoma (EwS) has been poor. The vast majority of children with metastatic or relapsed EwS die despite current intensive, multimodal therapy. The tumor immune microenvironment (TME) has a vital role in cancer survival and progression with implications in drug resistance and immune escape. However, there is a lack of understanding of the TME of EwS. Although recent single-cell RNA sequencing of EwS and immune cells have revealed a heterogenous transcriptional landscape with distinct subsets of immune cell populations in EwS, little is known about the spatial organization and spatial microenvironmental niches of the TME of EwS.
Methods: We performed Spatial Transcriptomics (ST) on 16 primary treatment naïve EwS tumor biopsies from patients with localized EwS (L-EwS) or with metastatic EwS (M-EwS), complemented by high-plex spatial proteomic analysis.
Results: Integrated analysis revealed inter- and intra-tumoral heterogeneity. We inferred the stromal regions of tumors transcriptionally and noted that tumors from L-EwS had significantly more stromal signature than M-EwS (p-value <2.2e-16). Gene set enrichment analysis using Hallmark gene sets revealed that L-EwS tumors were enriched in epithelial mesenchymal transition (EMT) and inflammatory signatures (adjusted p-value <0.05) and M-EwS tumors were enriched in proliferative signatures (adjusted p-value <0.05). We identified a set of 46 unique genes enriched in L-EwS that overlapped with genes in EMT hallmark pathways and were predominantly extracellular matrix related (ECM-r) genes such as COL3A1, COL1A2, ITGB1, MMP2, ACTA2, TNC, TGFB1. These ECM-r genes spatially overlapped with the stromal regions of individual tumors. Through spatial ligand-receptor analysis, we showed that the stromal enriched regions harbor unique extracellular matrix related cytokines, immune recruitment and proinflammatory microenvironmental signals, implying EwS stroma may play an anti-tumor role by acting as an immune recruitment center. All EwS tumors expressed pro-tumorigenic MIF-CD74 immune signaling connectivity, suggesting a potential immune-evasive mechanism.
Conclusion: L-EwS tumors are enriched in ECM and ECM-related microenvironmental signals compared to M-EwS. Spatial cellular microenvironmental signals reveal the potential immune recruitment role of tumor-associated stroma, our findings provide spatial insight into the TME of EwS and provide a rationale for the preclinical investigation of MIF as a potential target for EwS immunotherapy.
利益披露 Disclosure
K. Giannikou, None..
N. Shillingford, None.