KLRD1 and neoplasm: By analyzing the Pearson correlation between gene expression z-scores and GSVA scores for 14 tumor-related states, it was found that in HNSC, KLRD1 is positively correlated with the activity of several pathways, including angiogenesis, apoptosis, differentiation, DNA damage, epithelial-mesenchymal transition, stemness, quiescence, proliferation, metastasis, invasion, and inflammation (Figure 4A).