RGD peptide (
Arg-Gly-Asp tripeptide) binds to
integrin αVβ(3) and αVβ(5), which is selectively expressed in
tumor neovasculature and on the surface of some
tumor cells. Some studies showed that coupling the RGD
peptides to anticancer drugs yielded compounds with increased efficiency against
tumors and lowered toxicity to normal tissues. The
melanoma differentiation-associated gene-7/
interleukin-24 gene (mda-7/IL-24) is a novel
tumor-suppressor/
cytokine gene that exhibits potent
tumor-suppressive activity without damaging normal cells. To enhance the antitumor effect, we inserted a
glycine residue into the wild type (mda-7/IL-24) between (164)Arg and (165)Asp to form a
RGD peptide, named RGD-mda-7, then expressed RGD-mda-7 in Escherichia coli. Herein, we describe the expression and purification of RGD-mda-7. We detected the characterizations of immunostimulatory activity,
tumor targeting, potent cytopathic effect, and apoptosis inducing exploited by RGD-mda-7 in
tumor cells, and also compared these characterizations with wtmda-7/IL-24. The data showed that RGD-mda-7 had more potent
tumor targeting and apoptosis-inducing effects than wtmda-7/IL-24.