title: Response of T lymphocyte populations in prostate cancer patients undergoing radiotherapy: influence of neoajuvant total androgen suppression.
abstract: BACKGROUND
  This study sought to better define the immunological impact of combining neoadjuvant total androgen suppression (TAS) with radiotherapy (xRT) in treating prostate cancer.
  
  
  METHODS
  Subjects selected (n = 37) were stage I-II prostate cancer patients meeting the eligibility requirements for RTOG protocols 94-08 or 94-13. Flow cytometric monitoring of circulating T helper (Th), T suppressor/cytotoxic (Ts), natural killer (NK) and B lymphocytes was performed weekly.
  
  
  RESULTS
  Significant reduction of all lymphocyte subsets occurred as a result of xRT. Comparison between treatment groups demonstrated that the B lymphocyte and NK lymphocyte radioresponse was not influenced by TAS, but the Th and Ts lymphocyte response was, with addition of TAS leading to less radiation-induced decline.
  
  
  CONCLUSIONS
  The basis for this T cell response is unclear, but may involve a TAS-induced reduction of testosterone's immunomodulation of T cell proliferation and apoptosis and/or a direct, TAS-induced thymic stimulation. Our data suggest that addition of TAS to xRT appears to have no detrimental effects on lymphocyte subsets, and, indeed, may have favorable effects on T cells.
authors.affiliation: Department of Radiation Oncology, East Carolina University Brody School of Medicine, Greenville, North Carolina 27858, USA. tracyr@mail.edu.ecu
authors.forename: Roberta M
authors.initials: RM
authors.lastname: Johnke
authors.forename: Judy M
authors.initials: JM
authors.lastname: Edwards
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Kovacs
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Evans
authors.forename: Barbara M
authors.initials: BM
authors.lastname: Daly
authors.forename: Ulf L
authors.initials: UL
authors.lastname: Karlsson
authors.forename: Tung-Kwang
authors.initials: TK
authors.lastname: Lee
authors.forename: Ron R
authors.initials: RR
authors.lastname: Allison
authors.forename: Hyder H
authors.initials: HH
authors.lastname: Arastu
authors.forename: Mickael J
authors.initials: MJ
authors.lastname: Cariveau
authors.forename: Kevin F
authors.initials: KF
authors.lastname: O'Brien
mesh_terms: D000368:Aged; D000726:Androgen Antagonists / Q000008:administration & dosage; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D005485:Flutamide / Q000008:administration & dosage; D017273:Goserelin / Q000008:administration & dosage; D006801:Humans; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D011471:Prostatic Neoplasms / Q000188:drug therapy / Q000276:immunology* / Q000532:radiotherapy / Q000628:therapy*; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000528:radiation effects
chemical_list: D000726:Androgen Antagonists; D018931:Antineoplastic Agents, Hormonal; D017273:Goserelin; D005485:Flutamide