Jab1/Csn5 Signaling in Breast Cancer

Abstract

c-Jun activation domain-binding protein1 (Jab1), also known as a monomer or the fifth component of the constitutive photomorphogenesis 9 signalosome (Csn5) complex, regulates cell proliferation, cell-cycle progression, and apoptosis and affects a series of pathways. Jab1/Csn5 also promotes cell transformation and tumorigenesis, and its overexpression in many tumor types suggests it is involved in cancer progression and closely associated with poor cancer prognosis. Jab1/Csn5 dysregulation contributes to oncogenesis by deactivating several tumor suppressors. Increasing evidence of the role of Jab1/Csn5 overexpression in breast and other cancers has spurred interest in Jab1/ Csn5 inhibitors for cancer therapy. In this chapter, we summarize the evidence demonstrating the importance of Jab1/Csn5 expression in breast and other cancers and review recent advances in dissecting the Jab1/Csn5 signaling pathway along with its potential as a therapeutic target for cancer.