Advances in and applications of proteasome inhibitors

With the recent US Food and Drug Administration approval of bortezomib (Velcade®) for the treatment of relapsed multiple myeloma, the proteasome has emerged as a new therapeutic target with diverse pathology. Drug discovery programs in academia and the pharmaceutical industry have developed a range of low nanomolar synthetic and natural inhibitors of the 20S proteasome core particle that have entered human clinical trials as significant anti-cancer and anti-inflammatory leads. Moreover, proteasome inhibitors continue to serve as valuable research tools in cellular biology through the elucidation of important biological processes associated with the ubiquitin–proteasome pathway of protein degradation. This review will highlight recent advances in the development and application of proteasome inhibitors.