The role of an immune signature for prognosis and immunotherapy response in endometrial cancer

Immunotherapy is a practical and promising treatment for advanced and recurrent endometrial cancer (EC). In this study, we identified an immune-related gene (IRG) signature to predict the overall survival (OS) and response to immune checkpoints inhibitors (ICIs) in patients with EC. The RNA expression profiles of EC were obtained from The Cancer Genome Atlas database and then were filtered for IRGs based on the Immport database. Using the conjoint Cox regression model, an immune signature consisting of seven risk IRGs (CBLC, PLA2G2A, TNF, NR3C1, APOD, TNFRSF18, and LTB) was developed. The immune signature was independent of other clinical factors and was superior to the traditional staging method for OS prediction in EC. Immunohistochemistry staining from the Human Protein Atlas database and quantitative real-time PCR analysis of EC samples were also performed to validate the expression levels of risk IRGs. By further analyzing the tumor microenvironment in EC, patients in the low-risk subgroup showed a higher immune cell infiltration status, which was associated with a better prognosis. Moreover, the tumor mutational burden and immunophenoscore analysis demonstrated that the low-risk subgroup was more sensitive to ICI-based immunotherapy. These findings might shed light on the development of targeted treatment and novel biomarkers for patients with EC.