Potent and selective chemical probe of hypoxic signalling downstream of HIF-α hydroxylation via VHL inhibition

Frost, Julianty and Galdeano, Carles and Soares, Pedro and Gadd, Morgan S and Grzes, Katarzyna M and Ellis, Lucy and Epemolu, Ola and Shimamura, Satoko and Bantscheff, Marcus and Grandi, Paola and Read, Kevin D and Cantrell, Doreen A and Rocha, Sonia and Ciulli, Alessio (2016) Potent and selective chemical probe of hypoxic signalling downstream of HIF-α hydroxylation via VHL inhibition. Nature Communications, 7: 13312. ISSN 2041-1723

Abstract

Chemical strategies to using small molecules to stimulate hypoxia inducible factors (HIFs) activity and trigger a hypoxic response under normoxic conditions, such as iron chelators and inhibitors of prolyl hydroxylase domain (PHD) enzymes, have broad-spectrum activities and off-target effects. Here we disclose VH298, a potent VHL inhibitor that stabilizes HIF-α and elicits a hypoxic response via a different mechanism, that is the blockade of the VHL:HIF-α protein-protein interaction downstream of HIF-α hydroxylation by PHD enzymes. We show that VH298 engages with high affinity and specificity with VHL as its only major cellular target, leading to selective on-target accumulation of hydroxylated HIF-α in a concentration- and time-dependent fashion in different cell lines, with subsequent upregulation of HIF-target genes at both mRNA and protein levels. VH298 represents a high-quality chemical probe of the HIF signalling cascade and an attractive starting point to the development of potential new therapeutics targeting hypoxia signalling.