Integration of scRNA-seq and bulk tissue RNA-seq data to identify cancer-associated fibroblast-related gene RGMA as a potential treatment target for esophageal cancer.

Abstract

Cancer-associated fibroblasts (CAFs) serve as key stromal components within tumor microenvironment (TME), playing a significant role in the development and outcome of esophageal cancer (EC). There is an urgent need to identify genes related to CAFs to improve treatment strategies. The scRNA-sequencing dataset GSE196756 were used to identify fibroblast-related genes. Additionally, a WGCNA analysis was also conducted to identify modules related to CAFs within the TCGA-esophageal carcinoma (ESCA) cohort. By taking the intersection of identified genes of these two sections, CAF-related genes were identified. Expression of RGMA in EC samples compared to normal controls was assessed by RT-qPCR and western blot. In vitro and in vivo experiments were conducted to assess the impact of RGMA on EC cell growth. Compared to adjacent normal tissues, the levels of RGMA were notably reduced in EC tissues. Reduced RGMA levels were linked to a poor prognosis for EC patients. Furthermore, RGMA was found to have a positive correlation with the expression of fibroblast-related gene DCN, and showed a negative correlation with the expression of tumor-promoting chemokines, CXCL1, CXCL3 and CXCL8. Functionally, RGMA overexpression strongly prevented ECA109 cell viability, proliferation and migration, as well as suppresses tumor growth in vivo, suggesting that RGMA may function as a tumor suppressor in EC. Additionally, RGMA levels were also remarkably decreased in human esophageal CAFs relative to esophageal fibroblast cells (NFs). Importantly, the downregulation of RGMA may facilitate the transdifferentiation of NFs into CAFs by activating Akt signaling or upregulating CXCL1, CXCL3, and CXCL8, subsequently contributing to ECA109 cell proliferation. Collectively, RGMA may serve as a prognostic marker and a potential therapeutic target for EC. Clinical trial number Not applicable.