The transcription protein SRY-box 9 (SOX9) is a member of the high-mobility-group box class DNA-binding proteins and centrally involved in human development processes.[13] It keeps the target cell within an undifferentiated state during development [14] and within this purpose several important pathways like Notch, TGFβ/SMAD and Wnt-β-catenin are additionally involved.[15,16] However, it could also be demonstrated that dys-regulation of SOX9 expression leads to tumourigenesis in several tissue subtypes and high expression of SOX9 enhanced the ability of cancer cells to metastasize.[17–19]. This evidence concerns the gene SOX9 and cancer.