IL4I1 in head and neck squamous cell carcinoma: A potential therapeutic target associated with immune infiltration

Abstract Interleukin 4-induced gene 1 (IL4I1) is associated with tumor immune invasion; however, its involvement in head and neck squamous cell carcinoma (HNSCC) is not well documented. Publicly accessible databases and our tissue mRNA sequencing result were used to evaluate IL4I1 expression in HNSCC. The Wilcoxon rank-sum test was performed to examine the relationship between clinicopathological characteristics and IL4I1 expression. Signaling pathways associated with IL4I1 expression were identified via gene set enrichment analysis (GSEA). The CIBERSORT algorithm and Tumor Immune Estimation Resource (TIMER) database were used to examine the relationship between IL4I1 expression, immune infiltration levels, and cumulative survival in HNSCC. The relationship between IL4I1 and immunotherapy response was explored. IL4I1 mRNA expression was higher in HNSCC than in normal tissues. The overexpression of IL4I1 was significantly correlated with more severe clinical stages. GSEA revealed that the mechanism of IL4I1 in regulating HNSCC was related to various immunity and immune-related signaling pathways. Additionally, IL4I1 expression levels positively correlated with differential immune cell infiltration, various immune biomarkers, and immunotherapy response in HNSCC. Our results suggest that IL4I1 may be a potential therapeutic target associated with immune infiltration in HNSCC and could contribute to the development of novel and effective treatment strategies.