title: Expression of human chorionic gonadotropin in testicular germ cell tumors.
abstract: BACKGROUND
  We have shown that most patients with seminomas have elevated serum concentrations of the free β subunit of human chorionic gonadotropin (hCGβ) and that in nonseminomatous testicular cancer, most of the hCG in the serum is hyperglycosylated (hCG-h). However, the tissue expression of hCG-h or hCGβ in germ cell tumors (GCTs) has not been reported. Our objective was to study the expression and diagnostic value of hCG-h and hCGβ in testicular GCTs.
  
  
  METHODS
  We studied the immunohistochemical expression of hCG, hCG-h, hCGβ, and the free α subunit of hCG (hCGα) in GCTs from 154 patients. We compared the tissue expression with serum concentrations and evaluated the correlation between staining intensity, established prognostic variables, and outcome.
  
  
  RESULTS
  The expression varied between tumor types. All forms of hCG, including hCG-h, were detected in embryonal carcinomas (22%) and mixed GCTs (48%). Polyclonal hCG and monoclonal hCGβ antibodies detected immunoreactivity in some seminomas (7%). No form of hCG was found in spermatocytic seminomas, pure teratomas, or a yolk sac tumor. The serum concentrations correlated with the corresponding tumor expression. The staining intensities of hCG, hCGβ, hCG-h, and hCGα correlated with disease stage but not significantly with relapse, disease-related mortality, or progression-free survival.
  
  
  CONCLUSIONS
  Trophoblastic tissue expresses hCG, hCG-h, and free subunits together whereas seminoma tissue occasionally expresses hCGβ. This difference might aid in differential diagnosis of some difficult-to-classify cases.
authors: Department of Clinical Chemistry, Helsinki University Central Hospital Laboratory Division (HUSLAB) and Helsinki University, Helsinki, Finland. Electronic address: anna.lempiainen@helsinki.fi.
authors: Anna
authors: A
authors: Lempiäinen
authors: Department of Pathology, Helsinki University Central Hospital Laboratory Division (HUSLAB), Helsinki, Finland.
authors: Anna
authors: A
authors: Sankila
authors: Department of Clinical Chemistry, Helsinki University Central Hospital Laboratory Division (HUSLAB) and Helsinki University, Helsinki, Finland.
authors: Kristina
authors: K
authors: Hotakainen
authors: Department of Surgery, Helsinki University Central Hospital and Helsinki University, Helsinki, Finland.
authors: Caj
authors: C
authors: Haglund
authors: Department of Oncology, Helsinki University Central Hospital and Helsinki University, Helsinki, Finland.
authors: Carl
authors: C
authors: Blomqvist
authors: Department of Clinical Chemistry, Helsinki University Central Hospital Laboratory Division (HUSLAB) and Helsinki University, Helsinki, Finland.
authors: Ulf-Håkan
authors: UH
authors: Stenman
mesh_terms: D006063:Chorionic Gonadotropin / Q000378:metabolism*; D018572:Disease-Free Survival; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D009373:Neoplasms, Germ Cell and Embryonal / Q000378:metabolism*; D012008:Recurrence; D012074:Remission Induction; D018239:Seminoma / Q000378:metabolism; D013736:Testicular Neoplasms / Q000378:metabolism*
chemical_list: D006063:Chorionic Gonadotropin
keywords: Free β subunit of hCG; Germ cell tumor; Glycosylation; Hyperglycosylated hCG; Testicular cancer; hCG