ZOL-mediated p53 up-regulation was not involved in the ZOL-induced cytotoxicity in EHMES-10 cells, and in MSTO-211H cells at least at low concentrations at which synergistic effects were observed with CDDP, but contributed to combinatory anti-tumor effects of CDDP or Ad-p53. The gene discussed is TP53; the disease is neoplasm.