In these studies, in irradiation-resistant p53-mutated lymphoma cell lines (Namalwa and WI-L2-NS, mutant p53-M237I) but not in their sensitive p53 wild-type counterparts (TK6), the low background expression of OCT4 and NANOG was upregulated by ionizing radiation, with protein accumulation evident in PGCCs. This evidence concerns the gene POU5F1 and lymphoma.