RGD-IL-24, A Novel Tumor-Targeted Fusion Cytokine: Expression, Purification and Functional Evaluation

Targeting drugs to tumor cells is a central challenge for improving existing cancer therapies. ACDCRGDCFCG peptide (RGD-4C) binds to alpha v beta 3 integrin, which is selectively expressed in tumor blood vessels and on the surface of some tumor cells. Interleukin 24 (IL-24) is a novel cancer growth-suppressing and apoptosis-inducing cytokine. To enhance the antitumor effect, we coupled RGD-4C to the N-terminus of IL-24 and expressed RGD-IL-24 in Escherichia coli. Cell proliferation and adhesion experiments revealed that RGD-IL-24 specifically binds to MCF-7 cancer cells, and induces apoptosis of MCF-7 cancer cells. These studies support the use of the RGD-IL-24 protein in tumor-targeting therapy.