POU5F1 and head and neck squamous cell carcinoma: When relative Oct4/CIP2A mRNA expression values of six different HNSCC cell lines with the highest and lowest double Oct4/CIP2A expression index were compared to the area under the survival curve values (AUC), a tendency between Oct4/CIP2A double positivity and the intrinsic radioresistancy was observed (Table 3, Fig. 5E).