Advancement of studies on second mitochondrial activator of caspase / 生物医学工程学杂志

ABSTRACT

Smac is a mitochondrial protein that interacts with inhibitor of apoptosis proteins (IAPs). Upon apoptotic stimuli, the Smac is released into the cytoplasm to inhibit the capase-binding activity of IAPs. The low expression of Smac in tissues has been reported existing in various cancers. Smac plays key roles in prognosis and chemoradiotherapy resistance of malignant tumor besides neoplasm genesis and growth. Furthermore, Smac may be a molecular therapeutic target in cancer patients. Overexpression of Smac by transfecting extrinsic Smac gene or Smac mimetic into tumor cell can improve their sensitivity to radiotherapy and chemotherapy, which has great significance to the treatment of tumor. Our review will focus on the roles of Smac in structure, pro-apoptotic mechanism, tissue distribution and cancer treatment.