Enzyme prodrug therapy designed to target l-methioninase to the tumor vasculature

A new approach for enzyme prodrug therapy for cancer was tested using human endothelial cells and two breast cancer cell lines in vitro. The concept is to use the human annexin V protein to selectively target the enzyme l-methioninase to the tumor vasculature. The major finding was that enzyme prodrug treatment using the l-methioninase-annexin V fusion protein and selenomethionine as the prodrug over 3 days was shown to be lethal to the endothelial cells and the cancer cells, while having little or no effect with the prodrug but with no fusion protein present. Thus, this new approach appears promising.