In addition, in 6 cancer types (TGCT, PRAD, CESC, LIHC, KICH, and STAD), the upregulation of PLK1 was associated with higher levels of NK cell infiltration, and in 1 cancer type (LUAD), we observed an opposite trend (Spearman correlation, FDR<0.1) (Figure 1(d)). Here, PLK1 is linked to cancer.