Immunoactivative role of indoleamine 2,3-dioxygenase in gastric cancer cells in vitro

Rupeng Zhang, Hui Li, Jinpu Yu, Jingzhu Zhao, Xuejun Wang, Gang Wang, Zhoujia Yao, Feng Wei, Qiang Xue, Xiubao Ren

    Research output: Contribution to journalArticle

    9 Scopus citations


    To study the role of indoleamine 2,3-dioxygenase (IDO) in immune response and immune escape in gastric cancer, the human IDO gene was cloned by reverse transcription-polymerase chain reaction (RT-PCR) and inserted into the pIRES2-EGFP vector to construct the IDO expression vector (pIRES 2-EGFP-IDO). BGC-823 cells were transfected with the vector by electroporation and selected stable expression with G418. IDO expression was determined by RT-PCR and Western blot analysis. The enzymatic activity of IDO was estimated by determining tryptophan and kynurenine concentrations in the cell culture medium by an amino acid analyzer. To assess the effect of IDO on T cell-mediated cytotoxicity and proliferation, T cells from patients with gastric cancer were co-cultured with the IDO-transfected BGC-823 cells in the presence or absence of 1-MT, a competitive inhibitor of IDO. Cells transfected with the vector expressed high levels of IDO mRNA and protein, and a significantly higher level of kynurenic acid was detected in the culture medium of the transfected cells compared to the non-transfected cells (P<0.001). T cells co-cultured with the IDO-transfected cells exhibited significantly lower cytotoxicity compared to the control group (P<0.05). Additionally, IDO-transfected cells treated with 1-MT exhibited higher toxicity compared to the untreated IDO-transfected cells (P<0.01). We conclude that IDO plays a key role in gastric cancer immune suppression, possibly by inhibiting T cell-mediated cytotoxicity and proliferation in vitro.

    Original languageEnglish (US)
    Pages (from-to)169-173
    Number of pages5
    JournalMolecular medicine reports
    Issue number1
    StatePublished - Jan 1 2011



    • 3-dioxygenase
    • Gastric cancer
    • Indoleamine 2
    • T cell cytotoxicity
    • T cell proliferation
    • Tumor escape

    ASJC Scopus subject areas

    • Biochemistry
    • Molecular Medicine
    • Molecular Biology
    • Genetics
    • Oncology
    • Cancer Research

    Cite this

    Zhang, R., Li, H., Yu, J., Zhao, J., Wang, X., Wang, G., Yao, Z., Wei, F., Xue, Q., & Ren, X. (2011). Immunoactivative role of indoleamine 2,3-dioxygenase in gastric cancer cells in vitro. Molecular medicine reports, 4(1), 169-173.