A downside to apoptosis in cancer therapy?

A recent study challenges the view that radiation-induced apoptosis is beneficial in tumor therapy by showing that caspase 3-mediated apoptosis in response to ionizing radiation activates a growth signaling cascade in tumor cells, thereby stimulating tumor repopulation (pages 860-866). These results may have important implications for the clinical use of radiotherapy or chemotherapy to induce apoptosis in tumors.