title: [Comparison of the expression profiles of cell death factors in articular cartilage between Kashin-Beck disease and osteoarthritis].
abstract: OBJECTIVE
  To compare the expressions of programmed cell death 5 (PDCD5) and early growth response protein-1 (EGR-1) in the articular cartilage between Kashin-Beck disease (KBD) and primary osteoarthritis and the roles of these factors in KBD cartilage.
  
  
  METHODS
  Cartilage specimens were collected from 10 confirmed KBD patients, 15 osteoarthritic patients and 6 healthy subjects. The expression levels of PDCD5 and EGR-1 in the cartilage were detected by immunohistochemistry staining, and the positive chondrocyte counts were recorded in the different layers of KBD and OA cartilages.
  
  
  RESULTS
  The KBD cartilages contained a significantly higher percentage of PDCD5-positive chondrocytes in the middle layer [(41.35 ± 2.97)%] than OA cartilages [(26.48 ± 2.04)%, P=0.001] and normal cartilages [(19.02 ± 1.88)%, P=0.000] with also obvious PDCD5 over-expression in the deeper layer compared to OA (P=0.000) and normal cartilages (P=0.029), but PDCD5 expression in the superficial layer of the cartilages showed no significant difference among the 3 groups(P>0.05). The average EGR-1 positivity rate in the superficial layer of the cartilage was significantly higher in KBD patients than in OA patients (P=0.000) and healthy controls (P=0.000), but in the middle layer, its positivity rate in KBD patients was higher than that in the normal control (P=0.017) but lower than that of OA cartilage (P=0.002); EGR-1 expression in the deeper layer was comparable in KBD and OA cartilages but both was higher than that in normal cartilages. PDCD5 and EGR-1 expressions were not correlated in either KBD or normal cartilages, but were positively correlated in the superficial layer of OA cartilages.
  
  
  CONCLUSIONS
  KBD cartilages show a significantly increased PDCD5 expression in the deeper layer and enhanced EGR-1 expression in both superficial and deeper layers, suggesting the involvement of PDCD5 and EGR-1 in the pathogenesis of KBD.
authors.affiliation: College of Public Health, Health Science Center, Key Laboratory of Environment and Gene Related Diseases of Ministry Education, Key Laboratory of Trace elements and Endemic Diseases, Ministry of Health, Xi'an Jiaotong University Health Science Center, Xi'an 710061, China.E-mail: wushixun313@stu.xjtu.edu.cn.
authors.forename: Shixun
authors.initials: S
authors.lastname: Wu
authors.forename: Xiong
authors.initials: X
authors.lastname: Guo
authors.forename: Feng
authors.initials: F
authors.lastname: Zhang
authors.forename: Jingjing
authors.initials: J
authors.lastname: Zheng
authors.forename: Zengtie
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism*; D002358:Cartilage, Articular / Q000378:metabolism* / Q000473:pathology; D019902:Chondrocytes / Q000378:metabolism; D051766:Early Growth Response Protein 1 / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D057767:Kashin-Beck Disease / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000378:metabolism*; D010003:Osteoarthritis / Q000378:metabolism*; D059467:Transcriptome
chemical_list: D051017:Apoptosis Regulatory Proteins; C497325:EGR1 protein, human; D051766:Early Growth Response Protein 1; D009363:Neoplasm Proteins; C117283:PDCD5 protein, human