Unfortunately, two of the OSKM reprogramming factors, c-Myc and Klf4, are oncogenes themselves, and their expression typically increases in metastatic cancer; Oct4 and Sox2 are also closely related to cancer (de Lázaro et al., 2017; Wang et al., 2019c; Ruiz et al., 2019). This evidence concerns the gene POU5F1 and cancer.