CD274 and head and neck squamous cell carcinoma: Using this data set, we observe an elastic sub-state of fibroblast differentiation and its negative prognostic impact that has not been previously described in HNSCC scRNAseq studies, and investigate cell-to-cell interactions of therapeutically relevant immune checkpoint receptor–ligand pairs, such as tumor-associated macrophages (TAM), which are major contributors of PD-L1 to CD8+ T cell interactions in HNSCC14.