[New face of antiapoptotic proteins. II. Survivin]

Survivin (mol.wt. 16.5 kDa; pI 5.1) belongs to the IAPs family--inhibitors of apoptosis. The human survivin protein contains an N-terminal BIR domain connected with a C-terminal, alpha-helical domain interacting with microtubules via a linker region. The BIR domain of the protein exhibits anti-apoptotic activity and plays a role in the binding of the chromosomal passenger complex (CPC) to the centromere regions of chromosomes. Alternative splicing of the human survivin gene gives rise to five different mRNA transcripts yielding wild-type survivin (142 aa) and four isoforms of the protein. In this review, the structure, features, and functions of wild-type survivin and its isoforms in the apoptotic process, cell cycle, and carcinogenesis as well as the significance of this protein as potential neoplastic marker are presented. Moreover, insights into the development of new anti-cancer therapeutic strategies targeting survivin are overviewed.