Overexpression of GNPDA1 in head and neck squamous cell carcinoma: Prognostic significance, immune infiltration, and correlation with cancer cell immune evasion.

To evaluate the correlation between glucosamine-6-phosphate isomerase 1 (GNPDA1) expression and prognosis, immune infiltration, and immune evasion in head and neck squamous cell carcinoma (HNSCC). We analyzed the expression of GNPDA1 in HNSCC tissues and obtained RNA sequence data from the Cancer Genome Atlas (TCGA) database. Kaplan-Meier survival analysis evaluated the relationship between GNPDA1 expression and advanced tumor stage, TNM stage, grading, and gender. Co-expressed genes with GNPDA1 were identified using TCGA data and annotated through gene ontology and Kyoto encyclopedia of genes and genomes analyses. A protein-protein interaction network was constructed using the STRING database. Single-sample gene set enrichment analysis was conducted based on TCGA and TIMER 2.0 databases to assess the correlation between GNPDA1 and immune infiltration. In addition, the location of GNPDA1 in tumor cell and immune cell structures was identified by the tumor immune stromal cells helper database, and potential protein-interacting molecules of GNPDA1 were elucidated in the STRING database. Potential GNPDA1 gene functions were assessed using gene set enrichment analysis. Our results indicate that the expression of GNPDA1 is elevated in HNSCC tissues (P < .05). GNPDA1 expression was positively correlated with tumor malignancy (P < .05) and negatively correlated with patient prognosis (P < .05). There was a significant correlation between high expression of GNPDA1 and advanced tumor stage, N-stage, or G-grade, and it was associated with gender. High GNPDA1 expression was associated with increased infiltration of resting CD4+T cells, macrophages M1 and M2, resting natural killer cells, monocytes, eosinophils, and naïve B cells (P < .05). In contrast, low GNPDA1 expression was associated with increased infiltration of activated natural killer cells, neutrophils, activated mast cells, macrophages M0, plasma cells, activated dendritic cells, CD8+T cells, memory B cells, regulatory T cells (Tregs), and naïve CD4+T cells (P < .05). In addition, GNPDA1 was observed to be closely associated with various immune evasion-related genes in HNSCC. The results of this study suggest that GNPDA1 can serve as a potential prognostic marker and therapeutic target for HNSCC and may be a key gene mediating immune evasion in HNSCC.