SOX2 and cancer: Increasing evidence indicates that cancer stem cells (CSCs) function crucially in the initiation of tumors and are the primary drivers of carcinoma metastasis.[158, 159, 160] The biological function of CSCs is regulated by pluripotent factors such as OCT4, SOX2, and NANOG, as is widely recognized.[161] Similar to the role in ESCs, BACH1 also induces lung cancer stem cell phenotypes by upregulating the expression of CD44.