POU5F1 and non-small cell lung carcinoma: A more recent study by Liu et al. observed increased Wnt/β-catenin signaling along with increased expression of the stem cell markers Oct4 and Nanog in gefitinib-resistant EGFR-mutant NSCLC cells and showed that over-expression of Oct4 and Nanog could stimulate Wnt/β-catenin signaling [112].