Caspase-7: A protease involved in apoptosis and inflammation

Department of Biochemistry, Ghent University, B-9000 Ghent, Belgium
The international journal of biochemistry & cell biology (Impact Factor: 4.24). 09/2009; 42(1):21-4. DOI: 10.1016/j.biocel.2009.09.013
Source: PubMed

ABSTRACT Caspase-7 was considered to be redundant with caspase-3 because these related cysteine proteases share an optimal peptide recognition sequence and have several endogenous protein substrates in common. In addition, both caspases are proteolytically activated by the initiator caspase-8 and -9 during death receptor- and DNA-damage-induced apoptosis, respectively. However, a growing body of biochemical and physiological data indicate that caspase-7 also differs in significant ways from caspase-3. For instance, several substrates are specifically cleaved by caspase-7, but not caspase-3. Moreover, caspase-7 activation requires caspase-1 inflammasomes under inflammatory conditions, while caspase-3 processing proceeds independently of caspase-1. Finally, caspase-7 deficient mice are resistant to endotoxemia, whereas caspase-3 knockout mice are susceptible. These findings suggest that specifically interfering with caspase-7 activation may hold therapeutic value for the treatment of cancer and inflammatory ailments.

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