Advances in tumor immune microenvironment of head and neck squamous cell carcinoma: A review of literature

Abstract

Squamous cell carcinoma is seen as principal malignancy of head and neck. Tumor immune microenvironment plays a vital role in the occurrence, development and treatment of head and neck squamous cell carcinoma (HNSCC). The effect of immunotherapy, in particular, is closely related to tumor immune microenvironment. This review searched for high-quality literature included within PubMed, Web of Science, and Scopus using the keywords "head and neck cancers," "tumor microenvironment" and "immunotherapy," with the view to summarizing the characteristics of HNSCC immune microenvironment and how various subsets of immune cells promote tumorigenesis. At the same time, based on the favorable prospects of immunotherapy having been shown currently, the study is committed to pinpointing the latest progress of HNSCC immunotherapy, which is of great significance in not only further guiding the diagnosis and treatment of HNSCC, but also conducting its prognostic judgement.

Figure 1.

The mutual effect of a variety of different cell subsets, related factors and pathways can regulate the development of tumor cells in the tumor immune microenvironment of head and neck cancer.

Figure 2.

In HNSCC, it is proved that immune checkpoints such as TIM-3, PD-1 and CTLA-4 give rise to immune escape by affecting T cell function. In contrast, drugs targeting immune checkpoints (e.g., Nivolumab, Pembrolizumab, ipilimumab tremelimumab, etc) can tremendously be beneficial for effective therapeutic effects in tumors by blocking the interaction between the receptor and its ligand. HNSCC = head and neck squamous cell carcinoma, TIM-3 = T-cell immunoglobulin mucin-3.