Considering that abnormality of cell adhesion, extracellular matrix, as well as enhancement of EMT process, were observed in our study by enrichment analysis, it might be speculated that upregulation of PLAU might promote tumor migration and invasion in HNSCC and have a clinical correlation with LN metastasis and distal metastasis. The gene discussed is PLAU; the disease is head and neck squamous cell carcinoma.