title: Clinical significance of EGF and EGFR expression changes in cryptorchid boys.
abstract: OBJECTIVE
  To explore the changes of epidermal growth factor (EGF) and epidermal growth factor receptor (EGFR) expressions in cryptorchid children and their clinical significance.
  
  
  METHODS
  The level of serum EGF was measured by radioimmunoassay (RIA) and the expression of EGFR by immunohistochemistry.
  
  
  RESULTS
  (1) The level of serum EGF was significantly lower in cryptorchid children than in normal subjects at age group of 5-9 years (P<0.01) and 10-14 years (P<0.01), (2) The level of EGF was significantly lower in boys with impalpable testis than in those with extracanalicular and intracanalicular testes (P<0.01), (3) The serum EGF level increased significantly 6 months after orchiopexy (P<0.05), (4) The EGFR expression in testicular Leydig's cells was lower in 2 approximately 4 year-old boys than in those over 5 years (P<0.05) and (5) the EGFR expression was less positive in the impalpable group and the intracanalicular group than that of the extracanalicular group (P<0.01).
  
  
  CONCLUSIONS
  The EGF and EGFR expressions may correlate with the age and the position of testes; orchiopexy improves the EGF and EGFR expressions in cryptorchid boys.
authors.affiliation: Department of Urology, First Affiliated Hospital, Medical School of Zhejiang University, Hangzhou 310003, China. ywy2008@163.com
authors.forename: Guo-Sheng
authors.initials: GS
authors.lastname: Yang
authors.forename: Ren-Kang
authors.initials: RK
authors.lastname: Lu
authors.forename: Zhao-Dian
authors.initials: ZD
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000375:Aging; D015415:Biomarkers / Q000032:analysis; D002648:Child; D002675:Child, Preschool; D003456:Cryptorchidism / Q000097:blood / Q000378:metabolism* / Q000473:pathology; D004815:Epidermal Growth Factor / Q000097:blood / Q000378:metabolism*; D066246:ErbB Receptors / Q000097:blood / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D007985:Leydig Cells / Q000378:metabolism / Q000473:pathology; D008297:Male
chemical_list: D015415:Biomarkers; D004815:Epidermal Growth Factor; D066246:ErbB Receptors