To find out whether the abovementioned CD8+ T cells contribute to the growth-inhibitory effect of FTS on the GL261 cells, we cocultured the CD8+ T cells (isolated, as described above, from FTS-pretreated GL261 tumor-bearing mice) with FTS-pretreated GL261 cells for 96 hours, then removed the CD8+ T cells and analyzed the viability of the GL261 cells (see Materials and Methods). The gene discussed is CD8A; the disease is neoplasm.