2003 年 28 巻 2 号 p. 207-213
In order to elucidate the role of transforming growth factor β1 (TGF-β1) in gastric cancer tissue, the influence of TGF-β1 produced by tumor cells on lymphocytes or stroma cells was investigated. Cancer cell strains taken from gastric cancer tissue were used to clarify TGF-β1 production by gastric cancer cells.Measurements by the ELISA method of TGF-β1 production volume in culture supernatant indicated that TGF-β1 of high NUGC-2 is produced. In addition, the culture supernatant of cell strains was used to investigate apoptosis induction in various cells, and it was found that conspicuous apoptosis is induced in T cell and B cell strains and that the same results were obtained with recombinant TGF-β1. Next, the contribution of the caspase family, the apoptosis praxis molecules, was analyzed and it was found that caspase 1, 3, and 8 are predominant in culture supernatant, whereas caspase 3 and 9 are predominant in recombinant TGF-β1. These results suggest that the humoral factors produced by gastric cancer cells, including TGF-β1, induce apoptosis in T and B lymphocytes by activating caspase, and thus could cause a reduction in tumor immunity.
