POU5F1 and cancer: The expression of Oct4, Nanog, Myc, Sox2, and Klf4 in the current study correlated well with data reported in the HPA which reveals expression of Oct4 in 88 % of cancers, Sox2 in 88 % of cancers, Myc in 78 % of cancers, Klf4 in 28 % of cancers, and Nanog in 7 % of cancers.