Since its discovery in a high‐throughput survivin gene promoter assay, the anticancer activity of YM155 has been reported in a wide variety of mouse tumor xenograft models.22, 23 YM‐155 shows synergistic antitumor activities with IL‐2 in renal cell carcinoma,24 and with ABT‐737 in human glioma cells.25 Previous reports have demonstrated that combination treatment can enhance the antitumor effect of YM‐155. This evidence concerns the gene IL2 and renal cell carcinoma.