title: Upregulation and inhibition of the nuclear translocation of Oct4 during             multistep gastric carcinogenesis.
abstract: Gastric cancer is the fourth most commonly diagnosed malignancy and the             second leading cause of cancer-related mortality worldwide. Recent research suggests             that tissue stem cells and the self renewal transcription factor, octamer-binding             transcription factor 4 (Oct4), could be involved in the development of certain             tumors. The aim of this study was to investigate the expression pattern of Oct4             in normal human stomach and during multistep gastric carcinogenesis. Pyloric antral             mucosal tissues were obtained from consenting individuals undergoing endoscopy             (due to upper gastrointestinal symptoms) and gastrectomy (due to pyloric antral             adenocarcinoma). Some tissue samples were processed to assemble an array of tissue             sections representing multistep carcinogenesis and probed using anti-Oct4 antibodies             and lectins specific for α-L-fucose or N-acetyl-D-glucosamine. Some tissue samples             were processed for subcellular fractionation and western blot analysis using the             same antibodies. The results revealed that Oct4-expressing cells were found in             the proliferative cell compartment of the pit-gland units of microscopically normal             gastric mucosal biopsies. Mucosal tissues with evidence of severe gastritis, metaplastic/dysplastic             transformation and gastric cancer showed a significant increase in the expression             of Oct4 (the labeled area increased from 2% in the control to 6 and 16% in the             gastritis and cancerous tissues, respectively), suggesting a role for Oct4 in             the early stages of cancer development. Furthermore, the data revealed an alteration             in the subcellular distribution of Oct4, possibly due to the inhibition of cytoplasm-to-nucleus             translocation during carcinogenesis. In conclusion, this study demonstrates an             alteration in the expression pattern and nuclear translocation of Oct4 during             gastric carcinogenesis and may be helpful in designing new modalities for the             early detection and/or therapy of gastric cancer.
authors.affiliation: Department of Anatomy, Faculty of Medicine and Health Sciences,                     UAE University, Al-Ain, United Arab Emirates.
authors.forename: Fathyia Y
authors.initials: FY
authors.lastname: Al-Marzoqee
authors.forename: Ghalia
authors.initials: G
authors.lastname: Khoder
authors.forename: Haifa
authors.initials: H
authors.lastname: Al-Awadhi
authors.forename: Rony
authors.initials: R
authors.lastname: John
authors.forename: Azam
authors.initials: A
authors.lastname: Beg
authors.forename: Aron
authors.initials: A
authors.lastname: Vincze
authors.forename: Frank
authors.initials: F
authors.lastname: Branicki
authors.forename: Sherif M
authors.initials: SM
authors.lastname: Karam
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002466:Cell Nucleolus / Q000378:metabolism*; D002471:Cell Transformation, Neoplastic / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism / Q000473:pathology; D005756:Gastritis / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D008875:Middle Aged; D050814:Octamer Transcription Factor-3 / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport; D013274:Stomach Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D055815:Young Adult
chemical_list: D050814:Octamer Transcription Factor-3; C494173:POU5F1 protein, human