In this study, we found that the expression of CD44 in gastric cancer was correlated with the infiltration degree of B memory cells, CD8+ T cells, CD4+ T cells, M1 macrophages, M2 macrophages, neutrophils, and dendritic cells (Fig. 6), similar analyses have been done in other tumours in the previous literature [17], but data are lacking in gastric cancer. Here, CD4 is linked to gastric cancer.