In situ activation and monitoring of the evolution of the intracellular caspase family. Issue 6 (14th April 2015)

• Record Type: Journal Article
• Authors: Zhang, Lei; Lei, Jianping; Liu, Jintong; Ma, Fengjiao; Ju, Huangxian
• Is Part Of: Chemical science. Volume 6:Issue 6(2015:Jun.)
• Page Start: 3365
• Page End: 3372
• Publication Date: 2015-04-14
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c5sc00471c
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : An intergrated nano-platform is designed to achieve in situ activation, monitoring and signal feedback of the caspase family evolution from upstream to downstream. Abstract : The evolution of the intracellular caspase family is crucial in cell apoptosis. To evaluate this process, a universal platform of in situ activation and monitoring of the evolution of intracellular caspase is designed. Using well-known gold nanostructure as a model of both nanocarrier and matter inducing the cell apoptosis for photothermal therapy, a nanoprobe is prepared by assembly of two kinds of dye-labelled peptides specific to upstream caspase-9 and downstream caspase-3 as the signal switch, and folic acid as a targeting moiety. The energy transfer from dyes to the gold nanocarrier at two surface plasmon resonance absorption wavelengths leads to their fluorescence quenching. Upon endocytosis of the nanoprobe to perform the therapy against cancer cells, the peptides are successively cleaved by intracellular caspase activation with the evolution from upstream to downstream, which lights up the fluorescence of the dyes sequentially, and can be used to quantify both caspase-9 and caspase-3 activities in cancer cells and to monitor their evolution in living mice. The recovered fluorescence could also be used to assess therapeutic efficiency. This work provides a novel powerful tool for studying the evolution of the intracellular caspase family and elucidating the biological roles of caspases in cancer cell apoptosis.