The Immune Infiltration in HNSCC and Its Clinical Value: A Comprehensive Study Based on the TCGA and GEO Databases.

Background. Being potential field of research for tumor immunological therapy, the head and neck squamous cell carcinoma (HNSCC) is one of most discussed types of tumor. Recently, some clinical trials have also used immunological therapy and demonstrated a subset of HNSCC patients who have shown a clear longer survival time. Objective. To conduct further studies and deeper research in the immunological oncology of HNSCC, a more detailed description and comprehending of the complicated landscape of immune infiltrative may be required. Methods. Firstly, we have described the fraction of different infiltrating immune cells in the HNSCC tumor and then compared it to the normal tissue, and secondly, we have explored the clinical implications of various infiltrated immune cell fractions meticulously. The gene expression profiles of HNSCC tissue were obtained from databases of TCGA and GEO and utilized the deconvolution algorithm (CIBERSORT) to presume the fractions of 22 several immune sensitive cells. Results. Our results indicated that the immune infiltrating cell fractions were considerably different between HNSCC tumor tissue and paired normal tissue, but at the same time, we found a potential internal correlation among the immune cells and also showed the association between immune infiltrating cells and their clinical characteristics. It is worth noting that the resting dendritic cells and M1 macrophages were linked with a favorable prognosis, while the CD4+ T cells with a poorer outcome. Conclusion. Fractions of immune cell percentage were also associated with tumors’ pathological grade, age, and TNM stage.