SOX2 and cancer: Hou et al. [25] and Oliphant et al. [26] both reported the crucial role of SIX homeobox 2 (SIX2) in promoting the stemness of tumor cells, Among them, Michael found that SIX2 can regulate SRY-Box Transcription Factor 2 (SOX2) and induce cancer stem cell programs to mediate advanced metastasis of triple-negative breast cancer, which is in line with our finding that SIX2 was an independent prognostic gene for colon cancer.