title: Tumour cell lysate-loaded dendritic cell vaccine induces biochemical and memory immune response in castration-resistant prostate cancer patients.
abstract: BACKGROUND
  Recently, we produced a tumour antigen-presenting cells (TAPCells) vaccine using a melanoma cell lysate, called TRIMEL, as an antigen source and an activation factor. Tumour antigen-presenting cells induced immunological responses and increased melanoma patient survival. Herein, we investigated the effect of TAPCells loaded with prostate cancer cell lysates (PCCL) as an antigen source, and TRIMEL as a dendritic cell (DC) activation factor; which were co-injected with the Concholepas concholepas haemocyanin (CCH) as an adjuvant on castration-resistant prostate cancer (CRPC) patients.
  
  
  METHODS
  The lysate mix capacity, for inducing T-cell activation, was analysed by flow cytometry and Elispot. Delayed-type hypersensitivity (DTH) reaction against PCCL, frequency of CD8(+) memory T cells (Tm) in blood and prostate-specific antigen (PSA) levels in serum were measured in treated patients.
  
  
  RESULTS
  The lysate mix induced functional mature DCs that were capable of activating PCCL-specific T cells. No relevant adverse reactions were observed. Six out of 14 patients showed a significant decrease in levels of PSA. DTH(+) patients showed a prolonged PSA doubling-time after treatment. Expansion of functional central and effector CD8(+) Tm were detected.
  
  
  CONCLUSIONS
  Treatment of CRPC patients with lysate-loaded TAPCells and CCH as an adjuvant is safe: generating biochemical and memory immune responses. However, the limited number of cases requires confirmation in a phase II clinical trial.
authors.affiliation: 1] Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago 8380453, Chile [2] Service of Urology, University of Chile Clinical Hospital, Santiago 8380453, Chile [3] Millennium Institute on Immunology and Immunotherapy, University of Chile, Santiago 8380453 Chile.
authors.forename: D
authors.initials: D
authors.lastname: Reyes
authors.forename: L
authors.initials: L
authors.lastname: Salazar
authors.forename: E
authors.initials: E
authors.lastname: Espinoza
authors.forename: C
authors.initials: C
authors.lastname: Pereda
authors.forename: E
authors.initials: E
authors.lastname: Castellón
authors.forename: R
authors.initials: R
authors.lastname: Valdevenito
authors.forename: C
authors.initials: C
authors.lastname: Huidobro
authors.forename: M
authors.initials: M
authors.lastname: Inés Becker
authors.forename: A
authors.initials: A
authors.lastname: Lladser
authors.forename: M N
authors.initials: MN
authors.lastname: López
authors.forename: F
authors.initials: F
authors.lastname: Salazar-Onfray
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019496:Cancer Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D045744:Cell Line, Tumor; D003713:Dendritic Cells / Q000276:immunology*; D006801:Humans; D016219:Immunotherapy, Adoptive / Q000379:methods*; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D064129:Prostatic Neoplasms, Castration-Resistant / Q000276:immunology* / Q000628:therapy*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology
chemical_list: D019496:Cancer Vaccines