The Proteasomal Subunits: Potential Therapeutic Targets for Cancer

Without doubt, we can understand that cancer such as breast cancer is considered as a heterogeneous disease. It consists of several molecular subtypes and each subtype has a unique signaling pathways with a distinct growth and proliferation stimulatory. Throughout the last few decades, the information about the cellular process and signaling pathways that involved in cancer become clearer. These cellular processes and signaling pathways have been reported to affect the survival, proliferation, migration, invasion and apoptosis of the cancer cells [1-4]. Indeed, these signaling pathways frequently have cross talk between each other either direct or indirect to maintain breast cancer cell signaling on which able to respond to the external stimulators. Most of the researcher nowadays focusing on targeting these signaling pathways which can disrupt the internal cross talk signals in the cancer cell. However, another recent field that the scientist working on is the proteasome. The ubiquitin proteasomal system (UPS) is an important regulator for cell growth and cellular apoptosis. In cancer, the function and activities of proteasome are altered. For example, in apoptosis, several signaling pathways are included from releasing cytochrome C, activation Apaf-I containing activation of caspases apoptosome complex [5], all of these process by mitochondria. UPS system has an important role in regulating caspase and some of the apoptosis marker like BCL-2. For that, targeting proteasome could exert anticancer effect by inducing apoptosis and may also exert antitumor effect in-vivo.