Dissecting Concurrent Chemoradiotherapy-Induced Landscape Alteration of Tumor Microenvironment in Locally Advanced Cervical Cancer at Single Cell Resolution

Abstract

We previously identified changes of immune cells in the cervical cancer microenvironment following concurrent chemoradiotherapy (CCRT) at single cell resolution. However, changes of other cells in the tumor microenvironment are unknown; thus, we further investigated CCRT-induced landscape alteration of all cells in the tumor microenvironment of locally advanced cervical cancer (LACC) using single-cell RNA sequencing.We performed single-cell RNA sequencing of 5 paired of tumor biopsies before and during CCRT in LACC patients and identified the subsets of epithelial cells, cancer-associated fibroblasts, immune cells, and endothelial cells and their alterations following CCRT. We also used immunostaining to validate our findings.Seven clusters of epithelial cells, 2 clusters of mCAF and 7 clusters of vCAF, 7 clusters of myeloid cells, 10 clusters of T cells and 2 clusters of NK cells, and 3 clusters of endothelial cells were identified in cervical cancer. Epithelial cells, mCAF and myeloid cells dramatic changed following CCRT. The proportion of a highly proliferate cluster of epithelial cells was decreased induced by CCRT, while a pre-malignant cluster of epithelial cells was predominant during CCRT. CCRT induced the transition of mCAF from one subset to another. For T cells, CCL5+CD8+ T cells, exhausted CD8+ T cells, and proliferate T cells were predominant before CCRT, but not during CCRT; cytotoxic CD8+ T cells were mainly existed in the tumor environment during CCRT.Our work reveals the landscape alteration of tumor microenvironment induced by CCRT in LACC patients at single-cell resolution.