SOX2 and cancer: In response to p62‐dependent autophagic clearance, the substrates are usually ubiquitinated for subsequent p62 recognition.36 Although the role of autophagy in cancer development is subject to debate, blocking p62 cargo function could promote cancer development by prohibiting the degradation of many oncoproteins via autophagy.37 In this study, we observed the induction of autophagy and SOX2 ubiquitination under gefitinib treatment.