Integrating single-cell and spatial transcriptomics to elucidate the cross-talk of SPP1+ macrophage and cancer associated fibroblast in HCC with immune excluded microenvironment

we comprehensively analyzed 38,439 cells from six HCC tumor tissues and 45,354 cells from matched adjacent normal tissues to reveal the cellular composition of HCC at single cell resolution. Importantly, we found SPP1+ macrophage in TME was indicative of poor patient survival. Then, we performed ST analysis, importantly we found SPP1+ macrophage colocalized with CAF and wrapped around the edge of tumor. Then we explore the possible interaction between SPP1+ macrophage and malignant hepatocytes and found malignant cells could alter the function of SPP1+ macrophage through hypoxia. We further evaluate the infiltration of SPP1+ macrophage and CAF in several independent HCC cohorts with bulk transcriptomics using our scRNA-seq as reference transcriptomics matrix and revealed a close correlation of the infiltration between these two cell subtypes. In addition, the colocalization of SPP1+ macrophage and CAF could limit the infiltration of immune cells in tumor core through promoting the extracellular matrix expression and stimulating the formation of the desmoplastic region.

我们对6份肝细胞癌（Hepatocellular carcinoma, HCC）肿瘤组织的38,439个细胞，以及匹配的癌旁正常组织的45,354个细胞开展了全面分析，以揭示肝细胞癌在单细胞分辨率下的细胞组成。值得注意的是，我们发现肿瘤微环境（Tumor Microenvironment, TME）中的SPP1阳性巨噬细胞可提示患者预后不良。随后我们进行了空间转录组学（Spatial Transcriptomics, ST）分析，进一步发现SPP1阳性巨噬细胞与癌相关成纤维细胞（Cancer-Associated Fibroblasts, CAF）共定位，并包裹于肿瘤边缘。我们还探究了SPP1阳性巨噬细胞与恶性肝细胞之间的潜在相互作用，发现恶性肿瘤细胞可通过缺氧微环境改变SPP1阳性巨噬细胞的功能。我们以本研究的单细胞RNA测序（single-cell RNA sequencing, scRNA-seq）数据作为参考转录组矩阵，在多个独立的肝细胞癌批量转录组学队列中评估了SPP1阳性巨噬细胞与癌相关成纤维细胞的浸润情况，揭示了这两种细胞亚型的浸润程度密切相关。此外，SPP1阳性巨噬细胞与癌相关成纤维细胞的共定位可通过促进细胞外基质表达、诱导促结缔组织增生区域形成，限制免疫细胞向肿瘤核心区域浸润。

搜集汇总

背景与挑战

背景概述

该数据集整合了单细胞和空间转录组学数据，揭示了HCC中SPP1+巨噬细胞与CAF的相互作用及其在免疫排斥微环境中的关键作用，为理解HCC的肿瘤微环境提供了重要见解。