Compositions comprising nanoparticles, such as silver or gold nanoparticles or carbon nanotubes (CNTs), and apoptotic agents are described. The nanoparticles can significantly enhance the cancer chemotherapeutic effects of the apoptotic agents. In particular, a highly increased anti-tumor activity has been demonstrated for the combination of etoposide and CNTs against HeLa cells compared to the administration of either etoposide alone or nanoparticles alone. Data provided by flow cytometry, Caspase 3 and other methods, suggest a strong interaction between the nanoparticles and the cellular structure, which can result in the improved effectiveness of chemotherapeutic agents. These findings provide potential new cancer therapies by carefully selecting the right combination of cytostatic drugs and nanostructural materials which synergistically provide significantly greater curative rates.