POU5F1 and head and neck squamous cell carcinoma: Analysis of the 77 CSC-related genes revealed a strong correlation of POU5F1, PSMC3IP, and RAD54L with CHEK-1, WEE1, and TAZ, the critical regulators of the homologous recombination, cell cycle, and CSC maintenance in the HNSCC TCGA patient dataset (Fig. 6A).