title: DEK expression in Merkel cell carcinoma and small cell carcinoma.
abstract: BACKGROUND
  The chromatin architectural factor DEK maps to chromosome 6p and is frequently overexpressed in several neoplasms, including small cell lung carcinoma, where it is associated with poor prognosis, tumor initiation activity and chemoresistance. DEK expression has not been studied in cutaneous Merkel cell carcinoma.
  
  
  METHODS
  We applied a DEK monoclonal antibody to 15 cases of Merkel cell carcinoma and 12 cases of small cell carcinoma. DEK nuclear immunoreactivity was scored based on percentage (0, negative; 1+, <25%; 2+, 25-50%; 3+, >50%) and intensity (weak, moderate or strong).
  
  
  RESULTS
  All 15 Merkel cell carcinoma cases (100%) showed diffuse (3+) nuclear positivity (14 strong, 1 weak). Six of 12 small cell carcinoma cases (50%) showed diffuse (3+) and strong nuclear positivity, while one case exhibited focal (1+) weak nuclear positivity. The remaining five cases were negative for DEK expression.
  
  
  CONCLUSIONS
  Our results suggest that DEK may be involved in the pathogenesis of Merkel cell carcinoma and therefore may provide therapeutic implications for Merkel cell carcinomas. In addition, the difference in DEK expression between Merkel cell carcinoma and small cell carcinoma suggests possible separate tumorigenesis pathways for the two tumors.
authors: Department of Pathology, University of Michigan Medical Center, Ann Arbor, MI, USA. rajivpat@umich.edu
authors: Rajiv M
authors: RM
authors: Patel
authors: Laura L
authors: LL
authors: Walters
authors: Ferdinand
authors: F
authors: Kappes
authors: Rohit
authors: R
authors: Mehra
authors: Douglas R
authors: DR
authors: Fullen
authors: David M
authors: DM
authors: Markovitz
authors: Linglei
authors: L
authors: Ma
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D015266:Carcinoma, Merkel Cell / Q000378:metabolism* / Q000556:secondary / Q000601:surgery; D018288:Carcinoma, Small Cell / Q000378:metabolism* / Q000556:secondary / Q000601:surgery; D002467:Cell Nucleus / Q000378:metabolism / Q000473:pathology; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D015513:Oncogene Proteins / Q000378:metabolism*; D000075223:Poly-ADP-Ribose Binding Proteins; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D046888:Tissue Array Analysis
chemical_list: D014408:Biomarkers, Tumor; D002868:Chromosomal Proteins, Non-Histone; C084738:DEK protein, human; D015513:Oncogene Proteins; D000075223:Poly-ADP-Ribose Binding Proteins