Synthesis and biological activity of an Anderson polyoxometalate bis-functionalized with a Bombesin-analog peptide

Polyoxometalates (POMs) are multi metallic and polyanionic oxides whose functionalization with organic moieties can generate new properties. Among possible strategies to generate molecular diversity and find applications in different fields, the postfunctionalization of a POM with peptides is particularly interesting and easily achievable. In this article, we present the functionalization of the Anderson-Evans polyoxomolybdate ([MnMo6O24]3-) with a Bombesin antagonist peptide, to highlight the interplay between these 2 domains, in terms of structural changes and assembly. Moreover, since Bombesin analogs show a marked binding affinity and specificity for some subtypes of the Gastrin Releasing Peptide Receptor (GRP-R), the impact of the peptide on the antitumor activity of the Anderson-Evans polyoxomolybdate POM has been explored.