Based on the analysis results of the heatmap and the TIMER database, we concluded that GTSE1 was positively correlated with EstimateScore, ImmuneScore, StromalScore, and infiltration of multiple immune cells, such as B cells (r = 0.22, p = 1.9e−06), CD8+ T cells (r = 0.165, p = 5.43e−04), CD4+ T cells (r = 0.251, p = 4.89e−08), macrophages (r = 0.165, p = 4.44e−04), neutrophils (r = 0.285, p = 5.47e−10), and dendritic cells (r = 0.33, p = 4.99e−13), but negatively correlated with tumor purity (Supplementary Figure S4). Here, CD4 is linked to neoplasm.