Identification of HuR-RNA Interfering Compounds by Dynamic Combinatorial Chemistry and Fluorescence Polarization

The RNA binding protein HuR regulates the post-transcriptional process of different oncogenes and tumorsuppressor genes, and its dysregulation is linked with cancer.Thus, modulating the complex HuR−RNA represents a promisinganticancer strategy. To search for novel HuR ligands able tointerfere with the HuR−RNA complex, the protein-templateddynamic combinatorial chemistry (pt-DCC) method was utilized.The recombinant RRM1+2 protein construct, which containsessential domains for ligand−HuR binding and exhibits enhancedsolubility and stability compared to the native protein, was used forpt-DCC. Seven acylhydrazones with over 80% amplification wereidentified. The binding of the fragments to HuR extracted fromDCC was validated using STD-NMR, and molecular modelingstudies revealed the ability of the compounds to bind HuR at the mRNA binding pocket. Notably, three compounds effectivelyinterfered with HuR−RNA binding in fluorescence polarization studies, suggesting their potential as foundational compounds fordeveloping anticancer HuR−RNA interfering agents