title: [MHC-class I expression on prostate carcinoma and modulation by IFN-gamma].
abstract: OBJECTIVE
  In this study, we investigated MHC-class I expression on both prostate cancer and normal prostate and compared those data with the number of CD8+ lymphocyte. Secondary, we investigated effect of IFN-gamma to the MHC-class I expression on prostate carcinoma.
  
  
  METHODS
  Twenty cryo-preserved benign prostate samples (Seven normal prostates and five benign prostatic hypertrophy samples.) and fifteen prostate carcinoma samples were used for immunohistochemistry of CD8 and MHC-class I. Eleven fresh single cell suspensions of prostate carcinoma were used for IFN-gamma study. After 24 hours IFN-gamma stimulation, MHC-I expression was measured by FACs analysis.
  
  
  RESULTS
  Interestingly, significant correlation was observed between MHC-class I expression and the CD8+ lymphocyte infiltrate (r = 0.705, P < 0.0001). After 24 hrs IFN-gamma stimulation, MHC-class I expression was up-regulated in all samples (p < 0.05).
  
  
  CONCLUSIONS
  Reduced expression of MHC-class I was thought as one of the factor which is related to the reduced degree of TILs (tumor infiltratig lymphocytes) in prostate cancer. IFN-gamma which is secreted mainly from CTL (cytotoxic T lymphocyte) might increase the degree of TIL through up-regulated MHC-class I.
authors.affiliation: Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA, Department of Urology, Showa University, School of Medicine, Tokyo, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Naoe
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Marumoto
authors.forename: Keiichiro
authors.initials: K
authors.lastname: Aoki
authors.forename: Takashi
authors.initials: T
authors.lastname: Fukagai
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Ogawa
authors.forename: Ryoutaro
authors.initials: R
authors.lastname: Ishizaki
authors.forename: Yoshizo
authors.initials: Y
authors.lastname: Nakagami
authors.forename: Hideki
authors.initials: H
authors.lastname: Yoshida
authors.forename: Michel
authors.initials: M
authors.lastname: Ballo
mesh_terms: D000368:Aged; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology; D002452:Cell Count; D015395:Histocompatibility Antigens Class I / Q000096:biosynthesis*; D006801:Humans; D007371:Interferon-gamma / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000276:immunology / Q000378:metabolism*; D013602:T-Lymphocytes, Cytotoxic / Q000166:cytology
chemical_list: D015395:Histocompatibility Antigens Class I; D007371:Interferon-gamma