Identification of HSP60 as a primary target of o-carboranylphenoxyacetanilide, an HIF-1alpha inhibitor.

We succeeded in the design and synthesis of multifunctional chemical probes of the HIF-1alpha inhibitor carboranylphenoxyacetanilide (1) that combine photoaffinity labeling and click reaction to identify the target protein. HSP60 was identified as a primary target protein of 1 using the chemical probes 2 and 3. Furthermore, HSP60 inhibitor 4 suppressed hypoxia-induced HIF activation, indicating that HSP60 affects HIF-1alpha accumulation directly or indirectly.