CCR7 affects the tumor microenvironment by regulating the activation of naïve CD8 T cells to promote the proliferation of oral squamous cell carcinoma.

Background: Head and neck cancer is the sixth most common malignancy worldwide, and oral squamous cell carcinoma (OSCC) is the most common head and neck cancer, being one of the leading causes of cancer morbidity and mortality worldwide. CC Chemokine receptor 7(CCR7) is a multifunctional G protein-coupled trans-membrane chemokine that affects immune cell chemotaxis, migration, and cancer progression through its interaction with its ligands C-C motif chemokine ligand 19(CCL19) and C-C motif chemokine ligand 21(CCL21). Numerous studies have demonstrated the involvement of CCR7 in the malignant progression of a variety of cancers, reflecting the pro-cancer properties of CCR7. The Cancer Genome Atlas data suggests CCR7 has elevated expression in oral cancer. Specifically, CCR7 expression in tumor microenvironment (TME) may regulate the ability of some immune cells to engage in anti-tumor immune responses. Since CD8 T cells have become a key immunotherapeutic target, the role of CCR7 in antitumor immune response of naïve CD8 T cells in TME has not been thoroughly investigated.

Methods: A CCR7 knockout mouse model was constructed, and the mechanism of ccr7 on the regulation of tumor microenvironment by naïve CD8 T cells was verified under the guidance of single-cell RNA sequencing combined with in vivo animal experiments and in vitro cell experiments.

Results: CCR7 is knocked out with impaired tumor growth and altered CD8 T cell profiles, revealing the importance of this protein in OSCC.

Conclusions: Inhibition of CCR7 enhances CD8 T cell activation, proliferation, and anti-tumor function, suggesting its potential as a therapeutic target.