The many faces of β-TrCP E3 ubiquitin ligases: reflections in the magic mirror of cancer

Beta-transducin repeats-containing proteins ( β -TrCP) serve as the substrate recognition subunits for the SCF β -TrCP E3 ubiquitin ligases. These ligases ubiquitinate specifically phosphorylated substrates and play a pivotal role in the regulation of cell division and various signal transduction pathways, which, in turn, are essential for many aspects of tumorigenesis. We review the functions of the SCF β -TrCP ligases in the light of their relevance to cell growth, survival and transformation. Mechanisms underlying β -TrCP regulation and their aberration in human and animal cancer as well as prospective of targeting β -TrCP as a means of anticancer therapy are also discussed.