Overexpression of fatty acid desaturase 3 predicts poor prognosis in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is one of the most common malignancies worldwide, because its discovery time is in the late stage of the disease, so it is important to develop HNSCC biomarkers to achieve the purpose of early detection and treatment. Fatty acid desaturase 3 (FADS3), the third member of the FADS family, is involved in sphingolipid biosynthesis. Here, we for the first time investigated FADS3 expression in HNSCC, as well as its potential biological function, prognostic value and its impact on the immune system. In this study, we used bioinformatics for gene expression analysis, clinicopathological analysis, enrichment analysis, and immune infiltration analysis of The Cancer Genome Atlas (TCGA) datasets. Statistical analysis was done using R. Tumor IMmune Estimation Resource (TIMER) and CIBERSORT were used to analyze the effect of FADS3 on immune responses in HNSCC. Gene Expression Profiling Interactive Analysis (GEPIA), Kaplan-Meier (KM) survival analysis, and the Human Protein Atlas (HPA) data were used to validate the results from bioinformatics analysis. Our findings indicate that FADS3 influences HNSCC prognosis. High expression of FADS3 is related to higher lymphatic metastasis, histologic grade, and lymphovascular invasion. Gene set enrichment analysis (GSEA) revealed that FADS3 is related to inhibition of amino acid metabolism. CIBERSORT analysis showed high FADS3 expression correlates with reduced levels of B cells. FADS3 is a marker of HNSCC, and high expression of FADS3 is associated with poor prognosis of HNSCC.