Proteasome Inhibitor-Based Cancer Drugs

The proteasome is an enzyme complex found within the cytoplasm of cells. It serves both as a disposal system for damaged cellular proteins and as a mechanism for degrading short-lived regulatory proteins that govern cellular functions such as the cell cycle, cell growth, and differentiation. Because these processes or their dysregulation are crucial steps in tumor formation, the proteasome pathway is a logical target for therapeutic intervention. The following mechanisms are involved in the relevant cancer drug action: (1) impede cancer cell proliferation by preventing the breakdown of certain valuable proteins and transcription factors that are known to hinder cancer cell growth; (2) reduce the survivability of cancer cells by inactivating certain genes and proteins that help cancer cells surviving; (3) cause cancer cell death by producing extreme cellular stress in tumor cells through disruption of cell proliferation.

Table 9. Proteasome Inhibitor Cancer Drugs

Velcade is the first proteasome inhibitor drug in market for multiple myeloma treatment.