POU5F1 and cancer: The CSC markers SOX2, OCT4, and Nanog have been demonstrated to promote the resistance of cancer to drugs including sorafenib, tamoxifen, cisplatin, and paclitaxel (Di and Zhao, 2015; Shan et al., 2012; Singh and Settleman, 2010; Vinogradov and Wei, 2012).