To investigate the correlation between TM4SF18 and immune infiltration, we downloaded the immune scores of GC patients from the TIMER database and analyzed them to find the correlation between the expression levels of TM4SF18 and Macrophage (cor = 0.348, P = 5.43e−12), neutrophil (cor = 0.285, P = 2.33e−08), and dendritic cell (cor = 0.314, P = 6.02e−10) infiltration levels and found them to be positively correlated (Fig. 6A). This evidence concerns the gene TM4SF18 and gastric cancer.