Characterization of the immune cell infiltration landscape in head and neck squamous cell carcinoma to aid immunotherapy
Abstract Background: The tumor microenvironment chiefly consists of tumor cells, and tumor-infiltrating immune cells admixed with the stromal component. The recent clinical trial has shown that the tumor immune cell infiltration is correlated with the sensitivity to immunotherapy and the prognosis of head and neck squamous cell carcinoma (HNSC). However, to date, the immune infiltrative landscape of HNSC has not yet been elucidated. Methods: We proposed two computational algorithms to unravel the immune infiltration landscape of 1029 HNSC patients. The Boruta algorithm and principal component algorithms (PCA) were employed to quantify three immune cell infiltration gene subtypes categorized as per the immune cell infiltrations pattern. Results: The high ICI score subtype was characterized by a higher tumor mutation burden (TMB) and the immune-activated signaling pathway. However, a low ICI score subtype was categorized as per the activation of immunosuppressive signaling pathways such as TGF-BETA, WNT signaling pathway, and lower TMB. Two immunotherapy cohorts confirmed patients with higher ICI score demonstrated significant therapeutic advantages and clinical benefits.Conclusions: This demonstrated that the ICI score could serve as an effective prognostic biomarker and predictive indicator for immunotherapy. A comprehensive understanding of the HNSC immune landscape might help in tailoring immunotherapeutic strategies for different patients.