title: The diagnostic value of cytokeratin 5/6, 14, 17, and 18 expression in human non-small cell lung cancer.
abstract: OBJECTIVE
  The expression patterns of cytokeratin (CK) filaments in human epithelial neoplasms are complex and distinctive. The aims of this study were to analyze CK expression and to evaluate the diagnostic application of CKs in human non-small cell lung cancer (NSCLC).
  
  
  METHODS
  mRNA expression of CK5, CK6, CK14, CK15, CK17, and CK19 was analyzed by Northern blotting. Protein expression of CK5/6, CK7, CK14, CK17, and CK18 was evaluated by immunohistochemistry on tissue microarrays.
  
  
  RESULTS
  Northern blotting showed that CKs were highly expressed in human bronchial epithelial cells and/or small airway epithelial cells. In NSCLC cell lines, the expression pattern of CKs was heterogeneous. Regarding protein expression of CKs in 95 primary lung tumors, expression of CK5/6, CK14, and CK17 proteins was increased in squamous cell carcinomas compared to adenocarcinomas (ADC; p = 0.001, p = 0.030, and p = 0.001, respectively), and higher expression was significantly associated with lower grading (p = 0.006, p = 0.002, and p = 0.001, respectively), while increased expression of CK7 and CK18 was observed in ADC (p = 0.001, respectively).
  
  
  CONCLUSIONS
  Our data suggest that CK5/6, CK7, CK14, CK17, and CK18 have diagnostic value in the subclassification of NSCLC.
authors.affiliation: Institute of Pathology, University Hospital Jena, Friedrich Schiller University Jena, Ziegelmühlenweg 1, Jena, Germany.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Chen
authors.forename: Tiantian
authors.initials: T
authors.lastname: Cui
authors.forename: Linlin
authors.initials: L
authors.lastname: Yang
authors.forename: Masoud
authors.initials: M
authors.lastname: Mireskandari
authors.forename: Thomas
authors.initials: T
authors.lastname: Knoesel
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhang
authors.forename: Manuela
authors.initials: M
authors.lastname: Pacyna-Gengelbach
authors.forename: Iver
authors.initials: I
authors.lastname: Petersen
mesh_terms: D000230:Adenocarcinoma / Q000737:chemistry; D014408:Biomarkers, Tumor / Q000032:analysis*; D015152:Blotting, Northern; D002289:Carcinoma, Non-Small-Cell Lung / Q000737:chemistry* / Q000473:pathology*; D002294:Carcinoma, Squamous Cell / Q000737:chemistry; D045744:Cell Line, Tumor; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D053547:Keratin-14 / Q000032:analysis; D053537:Keratin-17 / Q000032:analysis; D053538:Keratin-18 / Q000032:analysis; D053555:Keratin-5 / Q000032:analysis; D053553:Keratin-6 / Q000032:analysis; D053552:Keratin-7 / Q000032:analysis; D007633:Keratins / Q000032:analysis* / Q000235:genetics; D008175:Lung Neoplasms / Q000737:chemistry* / Q000473:pathology*; D040081:Protein Array Analysis; D012333:RNA, Messenger / Q000032:analysis
chemical_list: D014408:Biomarkers, Tumor; D053547:Keratin-14; D053537:Keratin-17; D053538:Keratin-18; D053555:Keratin-5; D053553:Keratin-6; D053552:Keratin-7; D012333:RNA, Messenger; D007633:Keratins