Drugs such as bortezomib, carfilzomib, and ixazomib are already approved for use in treating multiple myeloma and mantle cell lymphoma.
[2] Proteasome inhibitors are most commonly categorized into two different groups; Synthetic Analogs and Natural products.
The most common hypothesis is that when the proteasome is inhibited, it causes a buildup of proteins in the cell.
It does this by directly targeting the 20S proteasome itself instead of inhibiting the ubiquitination of proteins, or the identification of these substrates[7] 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.