Proteasome inhibitor

Proteasome inhibitors are drugs that block the action of proteasomes, cellular complexes that break down proteins. Multiple mechanisms are likely to be involved, but proteasome inhibition may prevent degradation of pro-apoptotic factors such as the p53 protein, permitting activation of programmed cell death in neoplastic cells dependent upon suppression of pro-apoptotic pathways. For example, bortezomib causes a rapid and dramatic change in the levels of intracellular peptides. Proteasome inhibitors are being studied in the treatment of cancer, and three are approved for use in multiple myeloma.

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