CD44 and head and neck squamous cell carcinoma: CD44v6 is mainly related to the activation of PI3K/Akt/GSK3β and the invasion and migration of HNSCC; CD44s and CD44v3 participate in the growth and migration of HNSCC 58,59 but the differences in CD44s and CD44 V1-V10 glycosylation structures and their corresponding functions have not been fully elucidated.