Depletion of PHLDB2 Suppresses Epithelial-Mesenchymal Transition and Enhances Anti-Tumor Immunity in Head and Neck Squamous Cell Carcinoma

The role of Pleckstrin homology-like domain family B member 2 (PHLDB2) in the regulation of cell migration has been extensively studied. However, the exploration of PHLDB2 in head and neck squamous cell carcinoma (HNSCC) is still limited in terms of expression, function, and therapeutic potential. In this study, we discovered an upregulation of PHLDB2 expression in HNSCC tissues which was correlated with a negative prognosis in patients with HNSCC. Additionally, we determined that a high level of expression of PHLDB2 is crucial for maintaining cell migration through the regulation of the epithelial-mesenchymal transition (EMT). Furthermore, we demonstrated that the ablation of PHLDB2 in tumor cells inhibited tumorigenicity in a C3H syngeneic tumor-bearing mouse model. Mechanistically, PHLDB2 was found to be involved in the regulation of T cell anti-tumor immunity, primarily by enhancing the activation and infiltration of CD8(+) T cells. In light of these findings, PHLDB2 emerges as a promising biomarker and therapeutic target for interventions in HNSCC.