The invention provides a polypeptide consisting essentially of a sequence corresponding to residues 163 to 199 of DP-1 as shown in the Figure, and fragments and variants thereof capable of antagonizing the heterodimerization of a DP protein with an E2F protein. Such peptides may be used to induce apoptosis in a cell by introducing into the cell an effective amount of said peptide. Such cells include cardiovascular cells, and the peptide may be delivered in a stent to treat or prevent restinosis.