CASP9 and cancer: It is worth noting that, compared with TmSm34/48 and TmSm34/48/84, the docking of TmSm34/84 with caspase-9 had the lowest value for Interface area (820.5 Å2) and the highest value for binding free energy (−3.0 kcal/mol), indicating that TmSm34/84 was more difficult to form a complex with caspase-9, thus acquiring a stronger ability to release caspase-9, and eventually showed the highest anti-cancer activity.