title: The role of p28GANK in rat oval cells activation and proliferation.
abstract: BACKGROUND
  Human gankyrin gene product (p28GANK) is a novel oncogenic protein ubiquitously overexpressed in hepatocellular carcinoma and also plays a role in cell cycle progression in normal hepatocytes and liver regeneration. However, little is known about the physiological role of p28GANK in the liver oval cell activation and proliferation. We investigated the possible involvement of p28GANK in oval cell-mediated liver regeneration and cell cycle progression.
  
  
  METHODS
  We examined the different p28GANK expression in 2-acetylaminofuorene/partial heptectomy (2-AAF/PH) rats, as a model of oval cell activation, and PH rats by Western blot and immunohistochemistry. Oval cells isolated from 2-AAF/PH rat model were cultured in our study. p28GANK expression was examined in the oval cells after mitogenic stimulation.
  
  
  RESULTS
  In 2-AAF/PH rats, p28GANK was expressed in the activated oval cells and located in the nucleus. p28GANK protein expression was increased in 2-AFF/PH rats after hepatectomy lasting for 96 h when retinoblastoma maintained hyperphosphorylation status at Ser-795. The isolated oval cells express AFP, OV6, CK19, CD34, CD45, c-kit and albumin. After epidermal growth factor stimulation, p28GANK protein was up-regulated in oval cells from 24 to 72 h, which coincided with increased expression of CyclinD1, CDK4 and decreased of Rb protein.
  
  
  CONCLUSIONS
  p28GANK expression was increased in oval cell-mediated liver regeneration and oval cells after mitogenic stimulation. Thus, p28GANK may play a role in oval cell-mediated liver regeneration and liver oval cell cycle progression.
authors.affiliation: International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, Shanghai, China.
authors.forename: Yun-Feng
authors.initials: YF
authors.lastname: Shan
authors.forename: Wei-Ping
authors.initials: WP
authors.lastname: Zhou
authors.forename: Xiao-Yong
authors.initials: XY
authors.lastname: Fu
authors.forename: He-Xing
authors.initials: HX
authors.lastname: Yan
authors.forename: Wen
authors.initials: W
authors.lastname: Yang
authors.forename: Shu-Qin
authors.initials: SQ
authors.lastname: Liu
authors.forename: Hui-Fang
authors.initials: HF
authors.lastname: Cao
authors.forename: Bin
authors.initials: B
authors.lastname: Kang
authors.forename: Meng-Chao
authors.initials: MC
authors.lastname: Wu
authors.forename: Hong-Yang
authors.initials: HY
authors.lastname: Wang
mesh_terms: D015073:2-Acetylaminofluorene / Q000633:toxicity; D000818:Animals; D017487:Ankyrins / Q000235:genetics / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D049109:Cell Proliferation / Q000187:drug effects; D002469:Cell Separation; D002478:Cells, Cultured; D003135:Common Bile Duct; D004815:Epidermal Growth Factor / Q000494:pharmacology; D006498:Hepatectomy; D008026:Ligation; D008099:Liver / Q000378:metabolism* / Q000473:pathology; D008106:Liver Cirrhosis, Experimental / Q000378:metabolism / Q000473:pathology; D008115:Liver Regeneration / Q000187:drug effects / Q000502:physiology*; D008297:Male; D046988:Proteasome Endopeptidase Complex / Q000235:genetics / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013234:Stem Cells / Q000378:metabolism* / Q000473:pathology; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D017487:Ankyrins; D015415:Biomarkers; C403591:PSMD10 protein, human; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D004815:Epidermal Growth Factor; D015073:2-Acetylaminofluorene; D046988:Proteasome Endopeptidase Complex