SNAI2 and head and neck squamous cell carcinoma: • Self-renewal, colony formation, migration, and invasion in HNSCC [126]. • Associated with overexpression of the EMT-related transcription factors Snail and Slug in ACC [127]. • Strong correlation with advanced stages, aggressive clinicopathological behaviors, stem cell-like properties, drug resistance, and poor prognosis in HNSCC [82, 128].