Wei Jinfen, Chen Zixi, Hu Meiling, He Ziqing, Jiang Dawei, Long Jie, Du Hongli
School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China.
Department of Thoracic Surgery, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.
Front Cell Dev Biol. 2021 Oct 5;9:749210. doi: 10.3389/fcell.2021.749210. eCollection 2021.
Hypoxia is a characteristic of tumor microenvironment (TME) and is a major contributor to tumor progression. Yet, subtype identification of tumor-associated non-malignant cells at single-cell resolution and how they influence cancer progression under hypoxia TME remain largely unexplored. Here, we used RNA-seq data of 424,194 single cells from 108 patients to identify the subtypes of cancer cells, stromal cells, and immune cells; to evaluate their hypoxia score; and also to uncover potential interaction signals between these cells across six cancer types. We identified SPP1+ tumor-associated macrophage (TAM) subpopulation potentially enhanced epithelial-mesenchymal transition (EMT) by interaction with cancer cells through paracrine pattern. We prioritized SPP1 as a TAM-secreted factor to act on cancer cells and found a significant enhanced migration phenotype and invasion ability in A549 lung cancer cells induced by recombinant protein SPP1. Besides, prognostic analysis indicated that a higher expression of was found to be related to worse clinical outcome in six cancer types. expression was higher in hypoxia-high macrophages based on single-cell data, which was further validated by an experiment that was upregulated in macrophages under hypoxia-cultured compared with normoxic conditions. Additionally, a differential analysis demonstrated that hypoxia potentially influences extracellular matrix remodeling, glycolysis, and interleukin-10 signal activation in various cancer types. Our work illuminates the clearer underlying mechanism in the intricate interaction between different cell subtypes within hypoxia TME and proposes the guidelines for the development of therapeutic targets specifically for patients with high proportion of SPP1+ TAMs in hypoxic lesions.
缺氧是肿瘤微环境(TME)的一个特征,也是肿瘤进展的主要促成因素。然而,以单细胞分辨率对肿瘤相关非恶性细胞进行亚型鉴定,以及它们在缺氧TME下如何影响癌症进展,在很大程度上仍未得到探索。在这里,我们使用了来自108名患者的424194个单细胞的RNA测序数据,以识别癌细胞、基质细胞和免疫细胞的亚型;评估它们的缺氧评分;并揭示这六种癌症类型中这些细胞之间潜在的相互作用信号。我们鉴定出SPP1+肿瘤相关巨噬细胞(TAM)亚群可能通过旁分泌模式与癌细胞相互作用,从而增强上皮-间质转化(EMT)。我们将SPP1作为一种TAM分泌因子作用于癌细胞,并发现重组蛋白SPP1诱导的A549肺癌细胞的迁移表型和侵袭能力显著增强。此外,预后分析表明,在六种癌症类型中,较高的[此处原文缺失具体基因或蛋白名称]表达与较差的临床结果相关。基于单细胞数据,[此处原文缺失具体基因或蛋白名称]在缺氧程度高的巨噬细胞中表达更高,与常氧条件相比,在缺氧培养的巨噬细胞中[此处原文缺失具体基因或蛋白名称]上调的实验进一步验证了这一点。此外,差异分析表明,缺氧可能影响各种癌症类型中的细胞外基质重塑、糖酵解和白细胞介素-10信号激活。我们的工作阐明了缺氧TME中不同细胞亚型之间复杂相互作用的更清晰潜在机制,并为针对缺氧病变中SPP1+TAM比例高的患者开发治疗靶点提出了指导原则。