Abstract
Tissue-resident memory T cells (T(RM)) are a specialized T cell population residing in peripheral tissues. The presence and potential impact of T(RM) in the tumor immune microenvironment (TIME) remain to be elucidated. Here, we systematically investigated the relationship between T(RM) and melanoma TIME based on multiple clinical single-cell RNA-seq datasets and developed signatures indicative of T(RM) infiltration. T(RM) infiltration is associated with longer overall survival and abundance of T cells, NK cells, M1 macrophages, and memory B cells in the TIME. A 22-gene T(RM)-derived risk score was further developed to effectively classify patients into low- and high-risk categories, distinguishing overall survival and immune activation, particularly in T cell-mediated responses. Altogether, our analysis suggests that T(RM) abundance is associated with melanoma TIME activation and patient survival, and the T(RM)-based machine learning model can potentially predict prognosis in melanoma patients.