title: Role of the stemness factors sox2, oct3/4, and nanog in gastric carcinoma.
abstract: BACKGROUND
  Cancer stem cells have been proposed to be responsible for cancer tumorigenicity, and then to persist in tumors as a distinct population and cause relapse and metastasis. Recently, the stemness factors Sox2, Oct3/4, and Nanog were associated with induced pluripotent stem cells, suggesting a correlation between these stemness factors and cancer stem cells. We therefore investigated the role of stemness factors in the tumorigenesis of human gastric cancer.
  
  
  METHODS
  A total of 290 patients who had undergone resection of a primary gastric cancer at our institute were enrolled. A curative R0 resection was performed for 253 of 290 patients, and the remaining 37 patients were treated with a palliative resection. The expression levels of Sox2, Oct3/4, and Nanog were analyzed by immunohistochemistry.
  
  
  RESULTS
  Sox2, Oct3/4, and Nanog expression were positive in 159 (55%), 129 (44%), and 28 (10%) of 290 gastric cancers, respectively. There was a statistically significant correlation between Sox2-positive or Oct3/4-negative expression and invasion depth, lymph node metastasis, or lymphatic invasion. In 253 patients with a curative resection, the prognosis of patients with Sox2-positive tumors or Oct3/4-negative tumors was significantly (P < 0.01 or P = 0.04, log-rank) worse than that of patients with Sox2-negative or Oct3/4-positive tumors, respectively. A multivariate analysis revealed the expression of Sox2 or Oct3/4 to be an independent prognostic factor (P = 0.01 or P = 0.04).
  
  
  CONCLUSIONS
  Sox2-positive expression or Oct3/4-negative expression might be associated with invasion of gastric cancer. Sox2 and Oct3/4 might be independent prognostic factors for patients with gastric cancer.
authors.affiliation: Department of Surgical Oncology, Institute of Geriatrics and Medical Science, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Junko
authors.initials: J
authors.lastname: Matsuoka
authors.forename: Masakazu
authors.initials: M
authors.lastname: Yashiro
authors.forename: Katsunobu
authors.initials: K
authors.lastname: Sakurai
authors.forename: Naoshi
authors.initials: N
authors.lastname: Kubo
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Tanaka
authors.forename: Kazuya
authors.initials: K
authors.lastname: Muguruma
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Sawada
authors.forename: Masaichi
authors.initials: M
authors.lastname: Ohira
authors.forename: Kosei
authors.initials: K
authors.lastname: Hirakawa
mesh_terms: D018398:Homeodomain Proteins / Q000032:analysis / Q000502:physiology*; D006801:Humans; D007150:Immunohistochemistry; D000071317:Nanog Homeobox Protein; D009361:Neoplasm Invasiveness; D050814:Octamer Transcription Factor-3 / Q000032:analysis / Q000502:physiology*; D011379:Prognosis; D055748:SOXB1 Transcription Factors / Q000032:analysis / Q000502:physiology*; D013274:Stomach Neoplasms / Q000209:etiology* / Q000401:mortality / Q000473:pathology
chemical_list: D018398:Homeodomain Proteins; C486780:NANOG protein, human; D000071317:Nanog Homeobox Protein; D050814:Octamer Transcription Factor-3; C494173:POU5F1 protein, human; C527782:SOX2 protein, human; D055748:SOXB1 Transcription Factors