P1GF-saporin fusion protein: a potential anti-angiogenic agent

Vascularization is an important step in tumor growth and metastasis. Tumor neovascularization can be considered, therefore, as a good target for antineoplastic therapy. In order to target saporin, a powerful plant toxin, in proximity of the tumor we fused the saporin coding sequence to that for placental growth factor-2 (P1GF-2). P1GF is an angiogenic factor involved in tumor neovascularization. The fusion protein P1GF-2-saporin was obtained by transient transfection of mammalian cells and released in the culture medium as a 57.5 kDa polypeptide. Selectivity and cytotoxic activity are reported as a preliminary step towards the evaluation of its in vivo antitumor activity.