Expression and functional characterization of tumor-targeted fusion protein composed of NGR peptide and 15-kDa actin fragment.

To induce tumor cell apoptosis, a modified 15 kDa actin linked with a peptide NGR "homing" into tumor or tumor vessels was expressed in Escherichia coli. After refolding and purification, this fusion protein NGR-15actin was labeled with FITC to testify whether NGR-15actin could integrate into the cytoskeleton. It was found that this targeted peptide could induce HepG2 and HeLa cells apoptosis through its effect on the cytoskeleton function by binding to cytoskeleton protein. Thus, targeted NGR-15actin could be a candidate molecule for the therapy of cancer.