3n5e

Publication Abstract from PubMed

Human thymidylate synthase is a homodimeric enzyme that plays a key role in DNA synthesis and is a target for several clinically important anticancer drugs that bind to its active site. We have designed peptides to specifically target its dimer interface. Here we show through X-ray diffraction, spectroscopic, kinetic, and calorimetric evidence that the peptides do indeed bind at the interface of the dimeric protein and stabilize its di-inactive form. The "LR" peptide binds at a previously unknown binding site and shows a previously undescribed mechanism for the allosteric inhibition of a homodimeric enzyme. It inhibits the intracellular enzyme in ovarian cancer cells and reduces cellular growth at low micromolar concentrations in both cisplatin-sensitive and -resistant cells without causing protein overexpression. This peptide demonstrates the potential of allosteric inhibition of hTS for overcoming platinum drug resistance in ovarian cancer.

Protein-protein interface-binding peptides inhibit the cancer therapy target human thymidylate synthase.,Cardinale D, Guaitoli G, Tondi D, Luciani R, Henrich S, Salo-Ahen OM, Ferrari S, Marverti G, Guerrieri D, Ligabue A, Frassineti C, Pozzi C, Mangani S, Fessas D, Guerrini R, Ponterini G, Wade RC, Costi MP Proc Natl Acad Sci U S A. 2011 Aug 23;108(34):E542-9. doi:, 10.1073/pnas.1104829108. Epub 2011 Jul 27. PMID:21795601^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.