IL4I1 and cancer: First, we explored the functions of these genes in fatty acid metabolism (Table S2), second, we compare FAMRGs expression in human adjacent normal versus 24 types of tumor tissues by UALCAN database, the result showed that ACSL5, PLA2G2D, IL4I1, PROCA1, UBE2L6 and PSME1 were significantly upregulated in the most cancer types from TCGA (Figure 5A–F), especially in HNSCC sample (Figure 5G–L).