title: Expression and clinical significance of protein tyrosine phosphatase nonreceptor 22 in resected thymoma.
abstract: BACKGROUND
  To investigate the expression and clinical significance of protein tyrosine phosphatase nonreceptor 22 (PTPN22) in thymoma, as well as the relationship between thymoma and myasthenia gravis (MG).
  
  
  METHODS
  The expression of PTPN22 in normal thymus (35 cases), thymoma without MG (50 cases), and thymoma with MG (45 cases) treated with surgery were detected by the EnVision two-step immunohistochemical staining method. We analyzed the relationship of thymoma with MG as well as some clinical factors, such as the Osserman classification for MC, age, gender, and course of disease before surgery. All data were analyzed using the SPSS software.
  
  
  RESULTS
  The positive rates of PTPN22 expression in thymoma with and without MG were 11.1% (5/45) and 24.0% (12/50), respectively, which were significantly lower than in the normal thymus (74.3%, 26/35). A significant difference was found between the positive rates of thymoma with and without MG. The expression level of PTPN22 had no relation to thymoma with MG and to the Osserman classification for MG, age, gender, and course of disease of the patient.
  
  
  CONCLUSIONS
  Minimal or no PTPN22 expression in thymoma may play an important role in the development of thymoma with MG, provide basis for further genetic research.
authors.affiliation: Department of Cardiothoracic Surgery, Tianjin Medical University General Hospital, Tianjin 300052, China. kevin@asiastm.org
authors.forename: Kai
authors.initials: K
authors.lastname: Zheng
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Guo
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D009157:Myasthenia Gravis / Q000150:complications / Q000201:enzymology; D054596:Protein Tyrosine Phosphatase, Non-Receptor Type 22 / Q000378:metabolism*; D013945:Thymoma / Q000150:complications / Q000201:enzymology* / Q000601:surgery; D013953:Thymus Neoplasms / Q000150:complications / Q000201:enzymology* / Q000601:surgery
chemical_list: D014408:Biomarkers, Tumor; D054596:Protein Tyrosine Phosphatase, Non-Receptor Type 22