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Published on: May 6, 2019
Effects of oral squamous cell carcinoma-derived TGF-beta1 on CD26/DPPIV expression in T cells
Takashi Uematsu1, Hitoshi Tanaka, Minoru Yamaoka
1Department of Oral and Maxillofacial Surgery, Matsumoto Dental University School of Dentistry, Nagano, Japan. uematsu@po.mdu.ac.jp
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.
Materials And 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.
Conclusion:
SCC-derived TGF-beta1 down-regulates CD26/DPPIV expression in T cells, resulting in decreased serum CD26/DPPIV activity in oral cancer patients.
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