Epithelial-to-mesenchymal transition and cancer stem(-like) cells in head and neck squamous cell carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is the 6th commonest cancer worldwide. Relapse, thought to involve cancer stem(-like) cells (CSCs), and the development of metastases are common and survival rates remain low. Epithelial-to-mesenchymal transition (EMT) is a key event in metastasis and increasing evidence suggests a link between EMT and CSCs. MicroRNAs regulate multiple cellular processes including EMT and have been implicated in a CSC phenotype. This review aims to highlight key events that are involved in EMT, discusses their relevance in HNSCC progression and metastasis and explores the possibility of targeting EMT as a novel therapy in HNSCC.