title: Effects of PSK on T and dendritic cells differentiation in gastric or colorectal cancer patients.
abstract: BACKGROUND
  Vaccine therapy targeting tumor antigens recognized by cytotoxic T cells (CTL) has been tried extensively. However, in a cancer-bearing state, the Th1/Th2 balance shifts to Th2 dominance, and this has been the obstacle to vaccine therapy to induce the CTL. DC1/DC2 subsets have also been reported to control the differentiation of Th subsets. The key to tumor immunotherapy is how to activate the DC1-Th1 lineage.
  
  
  METHODS
  Six normal adults and 14 patients with gastric or colorectal cancers, who gave informed consent, were studied. The Th1/Th2 and DC1/DC2 ratios were determined by FACS. IL-12 and IL-10 production from PBMC were measured by ELISA.
  
  
  RESULTS
  The Th1/Th2 and DC1/DC2 ratios were all significantly lower in the patients with gastric or colorectal cancers compared to normal adults. After protein-bound polysaccharide K (PSK) therapy in cancer patients, the Th1/Th2 balance shifted to Th1 dominance and the DC1/DC2 balance to DC1 dominance. IL-10 production was significantly decreased by PSK therapy.
  
  
  CONCLUSIONS
  In the cancer-bearing state, the Th1/Th2 and DC/1/DC2 balance becomes Th2- and DC2-dominant. PSK therapy results in a shift of the Th1/Th2 and DC1/DC2 balance towards Th1 and DC1 dominance. We plan to examine whether combining dendritic cells (DC) vaccination therapy with oral PSK enhances the induction of T cell and DC differentiation in cancer patients.
authors.affiliation: Department of Surgery 2, Fukushima Medical University, Japan. Kanazawa@cc.fmu.ac.jp
authors.forename: Masashi
authors.initials: M
authors.lastname: Kanazawa
authors.forename: Kazue
authors.initials: K
authors.lastname: Yoshihara
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Abe
authors.forename: Manabu
authors.initials: M
authors.lastname: Iwadate
authors.forename: Kumiko
authors.initials: K
authors.lastname: Watanabe
authors.forename: Satoshi
authors.initials: S
authors.lastname: Suzuki
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Endoh
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Takita
authors.forename: Kouji
authors.initials: K
authors.lastname: Sekikawa
authors.forename: Seiichi
authors.initials: S
authors.lastname: Takenoshita
authors.forename: Takashi
authors.initials: T
authors.lastname: Ogata
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Ohto
mesh_terms: D000328:Adult; D000903:Antibiotics, Antineoplastic / Q000627:therapeutic use*; D019496:Cancer Vaccines; D019070:Cell Lineage; D002469:Cell Separation; D015179:Colorectal Neoplasms / Q000188:drug therapy*; D003713:Dendritic Cells / Q000187:drug effects*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007167:Immunotherapy; D016753:Interleukin-10 / Q000378:metabolism; D018664:Interleukin-12 / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011509:Proteoglycans / Q000627:therapeutic use*; D013274:Stomach Neoplasms / Q000188:drug therapy*; D013601:T-Lymphocytes / Q000187:drug effects*; D018417:Th1 Cells / Q000378:metabolism; D018418:Th2 Cells / Q000378:metabolism; D013997:Time Factors
chemical_list: D000903:Antibiotics, Antineoplastic; D019496:Cancer Vaccines; D011509:Proteoglycans; D016753:Interleukin-10; D018664:Interleukin-12; C010770:polysaccharide-K