Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2003: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 2002: ¥2,300,000 (Direct Cost: ¥2,300,000)
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Research Abstract |
With the aim of elucidating the cytobiological significance of H genes in ovarian cancer cells, in this study we investigated changes in cell properties when H genes were transfected into cells. We inserted the human H-type sugar chain gene or a mouse α1,2-fucosyltransferase gene (MFUT-1,MFUT-2) into a mammalian expression vector, and then transfected the expression vector into cultures of human ovarian cancer cell line RMG-II. The H-type sugar chain gene encodes α1,2-fucosyltransferase, and its function is to add fucose. α1,2-Fucosyltransferase activity increased in the phenotypically transformed cells into which the human H gene and MFUT-1, MFUT-2 genes had been transfected, and the thin-layer chromatography immunostaining method showed that the level of expression of the Lewis Y-type sugar chain was higher than in the control RMG-II cell cultures. Expression of sialyl Lewis X-type sugar chains and sialyl-Lc4Cer was also observed in the control cells, but no expression of these sialylated sugar chains was observed in the phenotypic transformants. Assessment of cell properties showed that the phenotypically transformed cells into which the human H gene had been transfected were smaller than the control cells and that adhesion between the cells was stronger. Anticancer drug sensitivity testing showed that the phenotypically transformed cells were less sensitive to 5-FU than the control cells, and that the number of resistant cells was greater. These findings show that when an H gene is transfected into a human ovarian cancer cell line and α1,2-fucosyltransferase activity is increased, fucosylation of the cell membrane sugar chains increases, and sialylation decreases, and that these changes are accompanied by an increase in the strength of intercellular adhesion and a decrease in sensitivity to 5-FU. These findings suggest that fucosylated sugar chains contribute to intercellular adhesion strength and sensitivity to 5-FU in ovarian cancer cells.
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