title: The nuclear matrix shell proteome of human epidermis.
abstract: BACKGROUND
  Proteomic approaches have identified cancer specific biomarker proteins in the nuclear matrix fraction of cancer cells. We wanted to determine whether a similar approach could be used to investigate melanoma biomarkers.
  
  
  OBJECTIVE
  Since it was not clear that a nuclear matrix fraction could be isolated from the intact human epidermis, we first wanted to determine whether a nuclear matrix fraction could be isolated from the intact epidermis of human skin. If this was possible, we secondarily wanted to compare the proteome of cultured melanoma and carcinoma cells to that of the intact epidermis.
  
  
  METHODS
  We applied two-dimensional electrophoresis (2DGE) and LC/MS/MS to identify proteins isolated in the nuclear matrix shell protein fraction isolated from the human epidermis and from cultured primary skin and cancer cells.
  
  
  RESULTS
  A subcellular fractionation of intact epidermis succeeded in yielding a nuclear matrix shell which made up approximately 40% of total tissue protein. Only 5-10% of total cell protein was fractionated in the nuclear matrix shell of cultured skin cells. The nuclear matrix shell of the intact epidermis was distinguishable from cultured keratinocytes or HaCaT cells by expression of keratin 1. The nuclear matrix of the epidermis was distinguishable from melanocytes and melanoma cells by expression of vimentin in melanocyte-derived cells and by expression of desmoplakin in the intact epidermis.
  
  
  CONCLUSIONS
  The nuclear matrix-intermediate filament system can be isolated from the intact human epidermis. A careful examination of the protein composition of this subcellular fraction from the epidermis and skin cancers may identify useful cancer specific biomarkers.
authors.affiliation: Department of Radiation Oncology, University of Utah Health Sciences Center, Salt Lake City, UT 84132, United States.
authors.forename: Raymond L
authors.initials: RL
authors.lastname: Warters
authors.forename: Pamela B
authors.initials: PB
authors.lastname: Cassidy
authors.forename: Jeremy A
authors.initials: JA
authors.lastname: Sunseri
authors.forename: Krishna
authors.initials: K
authors.lastname: Parsawar
authors.forename: Sergey B
authors.initials: SB
authors.lastname: Zhuplatov
authors.forename: Gwen F
authors.initials: GF
authors.lastname: Kramer
authors.forename: Sancy A
authors.initials: SA
authors.lastname: Leachman
mesh_terms: D014408:Biomarkers, Tumor; D002467:Cell Nucleus / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods; D004817:Epidermis / Q000378:metabolism* / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007382:Intermediate Filaments / Q000378:metabolism; D007525:Isoelectric Focusing; D008544:Melanocytes / Q000378:metabolism; D008545:Melanoma / Q000378:metabolism*; D008954:Models, Biological; D020543:Proteome; D040901:Proteomics / Q000379:methods*; D012867:Skin / Q000378:metabolism; D013347:Subcellular Fractions / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D020543:Proteome