EGF and head and neck squamous cell carcinoma: miR-34a is downregulated in HNSCC and reduced expression is characteristic for samples with LN metastasis; its target gene AREG (ligand of epidermal growth factor) takes part in tumor development, suggesting that miR-34a may play a key role in the suppression of invasion and metastasis in HNSCC (Zhang et al. 2015a).