Antitumour peptide based on a protein derived from the horseshoe crab: CIGB‐552 a promising candidate for cancer therapy

Peptide‐based cancer therapy has been of great interest due to the unique advantages of peptides, such as their low MW, the ability to specifically target tumour cells, easily available and low toxicity in normal tissues. Therefore, identifying and synthesizing novel peptides could provide a promising option for cancer patients. The antitumour second generation peptide, CIGB‐552 has been developed as a candidate for cancer therapy. Proteomic and genomic studies have identified the intracellular protein COMMD1 as the specific target of CIGB‐552. This peptide penetrates to the inside tumour cells to induce the proteasomal degradation of RelA, causing the termination of NF‐κB signalling. The antitumour activity of CIGB‐552 has been validated in vitro in different human cancer cell lines, as well as in vivo in syngeneic and xenograft tumour mouse models and in dogs with different types of cancers. The aim of this review is to present and discuss the experimental data obtained on the action of CIGB‐552, including its mechanism of action and its therapeutic potential in human chronic diseases. This peptide is already in phase I clinical trials as antineoplastic drug and has also possible application for other inflammatory and metabolic conditions.