Single‐cell RNA sequencing reveals SERPINE1‐expressing CAFs remodelling tumour microenvironment in recurrent osteosarcoma

Abstract

Dear Editor, Osteosarcoma (OS) is widely regarded as the most common bone tumour, mainly affecting young adults. 1 Cancerassociated fibroblasts (CAFs), which are highly infiltrated in the tumour microenvironment (TME), could act as a novel target for cancer immunotherapy. 2,3 Single-cell RNA sequencing (scRNA-seq) has been regarded as one potent new method to investigate TME. We aim to uncover the roles of CAFs in recurrent OS with scRNA-seq and further provided novel treatment strategies for OS.Our study conducted scRNA-seq and bioinformatic analysis to uncover cellular clusters of OS tumour tissues. The cellular clusters of OS lesions were explored via two Gene Expression Omnibus (GEO) datasets of GSE152048 (BC) and GSE162454 (OS). Moreover, three paired OS lesions were utilised to further confirm the outcomes. After quality control, these two datasets were grouped into 14 cell clusters with the Uniform Manifold Approximation and Projection (UMAP) method according to the corresponding biomarkers (Figure 1A). Div-cells are the MKI67+ diverse cells with improved proliferation. We identified the cells in TME including: