TTN and head and neck squamous cell carcinoma: Then, we estimated the distribution of the mutations from the first 30 HNSCC driver genes with the highest frequency of mutation (TP53, TTN, CSMD3, SYNE1, etc.,) in the hot and cold immune groups, and found that except for CASP8, all other driver genes had an elevated frequency of mutation in the low-graded group (Figure 6C; Supplementary Table S7), implying that the mutations of CASP8 endowed HNSCC with a stronger immunity.