As shown in Fig. 1A, the expression of 15 (GLS, FDX1, LIPT1, ATP7B, SLC31A1, LIAS, DLAT, PDHA1, NFE2L2, PDHB, DLD, MTF1, CDKN2A, ATP7A, and DBT) of the 19 genes were significantly different between HNSCC and normal samples (P < 0.05). Here, GLS is linked to head and neck squamous cell carcinoma.