YAP1 and head and neck squamous cell carcinoma: Intriguingly, mutually exclusive copy number gains of chromosome 3q and 11q22 (where YAP1 is mapped to) have been reported in squamous cell carcinoma (Campbell et al., 2018) and consistently, YAP1 and WWTR1 amplification were also found to be mutually exclusive in HNSCC (Wang et al., 2018).