title: Effects of oral squamous cell carcinoma-derived TGF-beta1 on CD26/DPPIV expression in T cells.
abstract: BACKGROUND
  Enzymatic activity levels of serum CD26/dipeptidylpeptidase (DPP) IV in oral cancer patients are lower than those in healthy subjects. However, the mechanism for this decrease is not yet fully understood.
  
  
  METHODS
  The influence of malignant cell-derived cytokines on cell surface CD26/DPPIV expression in human T cells was analyzed using an oral squamous cell carcinoma (SCC) cell line, KB, and peripheral blood T cells.
  
  
  RESULTS
  Tumor growth factor (TGF)-beta1 in KB-conditioned medium (KBCM) down-regulated CD26/DPPIV expression in T cells, which was responsible for the decreased DPPIV activities in the cultured supernatant. Expression p27kip in T cells was maintained in addition to G1 arrest when cultured with KBCM but was abolished by inclusion of anti-TGF-beta1 antibody.
  
  
  CONCLUSIONS
  SCC-derived TGF-beta1 down-regulates CD26/DPPIV expression in T cells, resulting in decreased serum CD26/DPPIV activity in oral cancer patients.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Matsumoto Dental University School of Dentistry, Nagano, Japan. uematsu@po.mdu.ac.jp
authors.forename: Takashi
authors.initials: T
authors.lastname: Uematsu
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Tanaka
authors.forename: Minoru
authors.initials: M
authors.lastname: Yamaoka
authors.forename: Kiyofumi
authors.initials: K
authors.lastname: Furusawa
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000378:metabolism*; D002453:Cell Cycle; D002846:Chromatography, Affinity; D018920:Coculture Techniques; D017077:Culture Media, Conditioned; D018819:Dipeptidyl Peptidase 4 / Q000096:biosynthesis*; D015536:Down-Regulation; D006801:Humans; D007624:KB Cells; D008213:Lymphocyte Activation; D011480:Protease Inhibitors / Q000032:analysis / Q000378:metabolism; D013601:T-Lymphocytes / Q000201:enzymology* / Q000276:immunology; D016212:Transforming Growth Factor beta / Q000032:analysis / Q000378:metabolism / Q000502:physiology*; D053773:Transforming Growth Factor beta1
chemical_list: D017077:Culture Media, Conditioned; D011480:Protease Inhibitors; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D018819:Dipeptidyl Peptidase 4