Upregulation of PLAU in tumor tissues was associated with epithelial–mesenchymal transition, ECM degradation, cell proliferation, hypoxia, angiogenesis, stemness, and metastasis.37–39 However, there is a lack of research to date assessing the association between PLAU expression and immunomodulation of HNSCC. The gene discussed is PLAU; the disease is head and neck squamous cell carcinoma.