POU5F1 and head and neck squamous cell carcinoma: Notably, within five weeks, all mice (3/3) injected with UT-SCC-14 cells (CIP2A/Oct4 double positive) formed large palpable tumours (range 1.8-2.5 cm; Fig. 6C), whereas only 1/3 mice injected with low CIP2A expressing HNSCC cell line (UT-SCC-50) formed a barely detectable tumour (Fig. 6C).