EGFR TKI treatment increased the population of CSCs in EGFR-mutated NSCLC, and CSC-related markers, such as CD44, CD133, integrin α6, Oct4, Sox2, Nanog, and ALDH1, were highly expressed in patients with EGFR-TKI-resistant NSCLC [33,34]. The gene discussed is POU5F1; the disease is non-small cell lung carcinoma.