The potential efficacy and clinical feasibility of gene therapy for liver cancer were tested through therecombinant adenovirus-mediated (Ad-multigenes ) co-transfer of human wild-type p53, B7-l co-stimulation(CD8o) and granulocyte-macrophage colony-stimulating factor (GM-CSF) genes into human hepatocellular carcinoma cell lines. The treated cells underwent apoptosis with specific DNA fragmentation and became more sensitiveto cisplatin, a chemotherapeutic drug. Their growth was partly inhibited. Efficient proliferation and generation ofCTLs and cytokine production were induced in mixed lymphocytes through tumor cell reaction (MLTR) using peripheral blood T lymphocytes from donors as effector cells and Ad-multigenes or Ad-p53-transfected human hepatocellular carcinoma cells (HepG2 or BEL7402) as stimulator cells. Ad-multigenes-transfected rat carcinosarcomaWalker 256 cells were inoculated subcutaneously into normal rats. Fourteen days later, the activity of spleen cellsin rats inoculated with Ad-multigenes-transduced Walker 256 cells was higher than that in Ad-p53-transducedones. These findings suggest that adenovirus-mediated multigenes p53, B7-1 and GM-CSF can induce apoptosis ofliver cancer cells and initiate a potent antitumor immune response against them.
