SIX2 and breast carcinoma: Six2 directly binds the srr2 enhancer of SOX2 to promote the expression of SOX2 in breast cancer, indicating that a SIX2/SOX2 axis is necessary for effective metastatic cloning and highlighting the critical role of the stemness factor SOX2 in tumor growth at metastatic sites.42 In a previous study, miR-638 was found to inhibit the luciferase activity of a reporter gene connected to the 3′ UTR of SOX2 in CRC.43 SOX2 has also been confirmed to be a target of miR-200c, as miR-200c inhibits SOX2 expression and blocks PI3K–AKT pathway activity.