When analyzed for mechanisms of antitumor activity, the combination of YM155 plus doxorubicin increased the fraction of tumor cells with hypodiploid, that is sub-G1 DNA content by flow cytometry (Figure 6C), with increased cleavage of canonical apoptosis markers, including PARP and caspase-3, by Western blotting (Figure 6D). This evidence concerns the gene CASP3 and neoplasm.