Overexpression of the truncated form of Livin reveals a complex interaction with caspase-3

Int J Oncol. 2013 Jun;42(6):2037-45. doi: 10.3892/ijo.2013.1883. Epub 2013 Apr 4.

Abstract

Disruption in apoptosis are involved in cancer development and progression. Livin-β, has been identified as a critical modulator for cell death in several tumor cell lines. It was demonstrated that a truncated fragment of Livin-β (tLivin) without its N-terminal 52 amino acids is produced in cells through protein cleavage. However, the biological consequence of the cleavage remains largely ignored. In the present study, we report that tLivin exerted a pro-apoptotic effect on cells. The subcellular localization of tLivin was mainly restricted to the cytoplasm. To explore the underlying mechanism, we observed an elevated caspase-3 activity which may account for the apoptosis. Furthermore, we observed that tLivin was further cleaved into a smaller fragment in cells. This second cleavage was possibly related to activated caspase-3. The resulted C-terminal fragment (livC) was an anti-apoptotic factor. Our study may help to deepen our understanding of the role of Livin in the regulation of cell death.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / genetics
  • Adaptor Proteins, Signal Transducing / metabolism*
  • Antineoplastic Agents / pharmacology
  • Apoptosis / genetics*
  • Caspase 3 / metabolism*
  • Cell Line, Tumor / drug effects
  • Cisplatin / pharmacology
  • Cytoplasm / metabolism
  • Enzyme Activation
  • HEK293 Cells
  • Humans
  • Inhibitor of Apoptosis Proteins / genetics
  • Inhibitor of Apoptosis Proteins / metabolism*
  • Neoplasm Proteins / genetics
  • Neoplasm Proteins / metabolism*
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism

Substances

  • Adaptor Proteins, Signal Transducing
  • Antineoplastic Agents
  • BIRC7 protein, human
  • Inhibitor of Apoptosis Proteins
  • Neoplasm Proteins
  • Recombinant Proteins
  • Caspase 3
  • Cisplatin