FAT1 and head and neck squamous cell carcinoma: Similarly, in the HNSCC HN13 and CAL27, which express FAT1, knock-down of MIB2 led to in increased YAP/TAZ levels (Fig 4A and C), increased expression of YAP/TAZ target genes (Fig 4B and D) and reduced YAP/TAZ protein degradation (S5A and B Fig).