The results showed that the interactions between P-Tex and Tex clusters and APCs (especially DCs) in the HNSCC TME were mainly enriched in T cell activation and proliferation signaling pathways, such as CD70-, CD80-, ICOS-, and PD-L1-related signaling pathways (Figure 6a–b, Figure 6—figure supplement 1 and Supplementary file 10). This evidence concerns the gene ICOS and head and neck squamous cell carcinoma.