Exploring the prime site in caspases as a novel chemical strategy for understanding the mechanisms of cell death: a proof of concept study on necroptosis in cancer cells


Caspases participate in regulated cell death mechanisms and are divided into apoptotic and proinflammatory caspases. The main problem in identifying the unique role of a particular caspase in the mechanisms of regulated cell death is their overlapping substrate specificity; caspases recognize and hydrolyze similar peptide substrates. Most studies focus on examining the non-prime sites of the caspases, yet there is a need for novel and more precise chemical tools to identify the molecular participants and mechanisms of programmed cell death pathways. Therefore, we developed an innovative chemical approach that examines the prime area of the caspase active sites. This method permits the agile parallel solid-phase synthesis of caspase inhibitors with a high yield and purity. Using synthesized compounds we have shown the similarities and differences in the prime area of the caspase active site and, as a proof of concept, we demonstrated the exclusive role of caspase-8 in necroptosis.

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This project was funded by the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No. 661187 (to MP) and by National Science Centre in Poland (grant OPUS, UMO-2018/29/B/NZ102249 to MP). The Salvesen laboratory is supported by Sanford Burnham Prebys NCI Cancer Center Support Grant P30CA030199 and NIH grant (GM99040). The Drag laboratory is supported by the Foundation for Polish Science and National Science Centre in Poland.

Author information

MP and MD conceived the project, KG, GS, MD, and MP designed and KG and MP performed the experiments, MLG and SJS contributed new reagents and tools, KG, GS, MD, and MP drafted and edited the paper. All authors reviewed the results and approved the final version of the paper.

Correspondence to Marcin Drąg or Marcin Poręba.

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