title: SOX9 is a novel cancer stem cell marker surrogated by osteopontin in human hepatocellular carcinoma.
abstract: The current lack of cancer stem cell (CSC) markers that are easily evaluated by blood samples prevents the establishment of new therapeutic strategies in hepatocellular carcinoma (HCC). Herein, we examined whether sex determining region Y-box 9 (SOX9) represents a new CSC marker, and whether osteopontin (OPN) can be used as a surrogate marker of SOX9 in HCC. In HCC cell lines transfected with a SOX9 promoter-driven enhanced green fluorescence protein gene, FACS-isolated SOX9(+) cells were capable of self-renewal and differentiation into SOX9(-) cells, and displayed high proliferation capacity in vitro. Xenotransplantation experiments revealed that SOX9(+) cells reproduced, differentiated into SOX9(-) cells, and generated tumors at a high frequency in vivo. Moreover, SOX9(+) cells were found to be involved in epithelial-mesenchymal transition (EMT) and activation of TGFb/Smad signaling. Gain/loss of function experiments showed that SOX9 regulates Wnt/beta-catenin signaling, including cyclin D1 and OPN. Immunohistochemistry of 166 HCC surgical specimens and serum OPN measurements showed that compared to SOX9(-) patients, SOX9(+) patients had significantly poorer recurrence-free survival, stronger venous invasion, and higher serum OPN levels. In conclusion, SOX9 is a novel HCC-CSC marker regulating the Wnt/beta-catenin pathway and its downstream target, OPN. OPN is a useful surrogate marker of SOX9 in HCC.
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kawai
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Yasuchika
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Takamichi
authors.initials: T
authors.lastname: Ishii
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Yuya
authors.initials: Y
authors.lastname: Miyauchi
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Hidenobu
authors.initials: H
authors.lastname: Kojima
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Ryoya
authors.initials: R
authors.lastname: Yamaoka
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Hokahiro
authors.initials: H
authors.lastname: Katayama
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.|Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan.
authors.forename: Elena Yukie
authors.initials: EY
authors.lastname: Yoshitoshi
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Ogiso
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Sadahiko
authors.initials: S
authors.lastname: Kita
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.|Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan.
authors.forename: Katsutaro
authors.initials: K
authors.lastname: Yasuda
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Fukumitsu
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Komori
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Etsuro
authors.initials: E
authors.lastname: Hatano
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.|Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan.
authors.forename: Yoshiya
authors.initials: Y
authors.lastname: Kawaguchi
authors.affiliation: Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Uemoto
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000378:metabolism*; D006528:Carcinoma, Hepatocellular / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D045744:Cell Line, Tumor; D058750:Epithelial-Mesenchymal Transition; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D016513:Mice, SCID; D015999:Multivariate Analysis; D014411:Neoplastic Stem Cells / Q000378:metabolism*; D053495:Osteopontin / Q000378:metabolism*; D010641:Phenotype; D011379:Prognosis; D055758:SOX9 Transcription Factor / Q000378:metabolism*; D051785:Smad Proteins / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000378:metabolism; D060449:Wnt Signaling Pathway; D023041:Xenograft Model Antitumor Assays
chemical_list: D014408:Biomarkers, Tumor; D055758:SOX9 Transcription Factor; C527932:SOX9 protein, human; C506895:SPP1 protein, human; D051785:Smad Proteins; D016212:Transforming Growth Factor beta; C485184:enhanced green fluorescent protein; D053495:Osteopontin; D049452:Green Fluorescent Proteins