title: Protein extraction from methanol fixed paraffin embedded tissue blocks: A new possibility using cell blocks.
abstract: BACKGROUND
  Methanol fixed and paraffin embedded (MFPE) cellblocks are an essential cytology preparation. However, MFPE cellblocks often contain limited material and their relatively small size has caused them to be overlooked in biomarker discovery. Advances in the field of molecular biotechnology have made it possible to extract proteins from formalin fixed and paraffin embedded (FFPE) tissue blocks. In contrast, there are no established methods for extracting proteins from MFPE cellblocks. We investigated commonly available CHAPS (3-[(3-cholamidopropyl) dimethylammonio]-1-propanesulfonate) buffer, as well as two commercially available Qiagen(®) kits and compared their effectiveness on MFPE tissue for protein yields.
  
  
  METHODS
  MFPE blocks were made by Cellient™ automated system using human tissue specimens from normal and malignant specimens collected in ThinPrep™ Vials. Protein was extracted from Cellient-methanol fixed and paraffin embedded blocks with CHAPS buffer method as well as FFPE and Mammalian Qiagen(®) kits.
  
  
  RESULTS
  Comparison of protein yields demonstrated the effectiveness of various protein extraction methods on MFPE cellblocks.
  
  
  CONCLUSIONS
  In the current era of minimally invasive techniques to obtain minimal amount of tissue for diagnostic and prognostic purposes, the use of commercial and lab made buffer on low weight MFPE scrapings obtained by Cellient(®) processor opens new possibilities for protein biomarker research.
authors.affiliation: Address: Department of Pathology and Lab Medicine, Cooperative Human Tissue Network-Eastern Division, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Theresa J
authors.initials: TJ
authors.lastname: Kokkat
authors.affiliation: Address: Department of Pathology and Lab Medicine, Cooperative Human Tissue Network-Eastern Division, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Diane
authors.initials: D
authors.lastname: McGarvey
authors.affiliation: Address: Department of Pathology and Lab Medicine, Cooperative Human Tissue Network-Eastern Division, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Miral S
authors.initials: MS
authors.lastname: Patel
authors.affiliation: Address: Department of Pathology and Lab Medicine, Cooperative Human Tissue Network-Eastern Division, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Tieniber
authors.affiliation: Address: Department of Pathology and Lab Medicine, Cooperative Human Tissue Network-Eastern Division, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Virginia A
authors.initials: VA
authors.lastname: Livolsi
authors.affiliation: Address: Department of Pathology and Lab Medicine, Cooperative Human Tissue Network-Eastern Division, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Zubair W
authors.initials: ZW
authors.lastname: Baloch
keywords: CHAPS buffer; Cellblocks; Cellient; Qiagen; extraction; formalin fixed and paraffin embedded; methanol fixation; methanol fixed and paraffin embedded; protein