Figure 5. RAI2 expression was significantly associated with PD-L1 expression. (A) The effect of RAI2 copy number variation on the infiltration level of B cells, CD4+ T cells, macrophages and dendritic cells in STAD. (B) The heatmap of immune checkpoints based on RAI2 expression. (C) The correlation between RAI2 expression and CD274 expression in different databases. (D) CD274 mRNA expression decreased by RAI2 up-regulation.