173apoptosis induction in a particular cell type. Moreover, once initiated,
apoptosis is normally a fast process which in cell cultures is followed
by secondary necrosis having morphological and biochemical
unique signatures. Finally, it should also be noted that the function
of caspases has been verifi ed in processes separated from apoptosis
and that a multitude of caspase-independent cell death modes exist
[ 17 ]. To place caspase activity assay results in a biological context
may therefore be a more complicated challenge, requiring a spec-
trum of additional cell and molecular techniques.Acknowledgements
Work in the authors’ laboratory was supported by grants from the
Swedish and Stockholm Cancer Societies, the Swedish Research
Council, and the Swedish Childhood Cancer Foundation.References
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