Cytotoxic effect of sea anemone pore-forming toxin on K562 chronic myeloid leukemia cells

Chronic myelogenous leukemia (CML) is one of prevalent cancer in worldwide. In spite of various designed drugs, chemoresistance remains the main obstacle in cancer cure. Therefore, developing novel strategy for treatment of CML is an urgent need. Fragaceatoxin C (Fra C) is novel protein toxin from a sea anemone called actinia fragacea with great impacts against cells by pore formation and disturbing cell membrane integrity. The aim of this study was evaluation of Fra C toxin toxicity against K562. The bacteria cells harboring expression‌‌‌‌‌‌‌ vector of Fra C were induced by IPTG and purified by Ni2+-NTA sepharose affinity chromatography. Then, purified toxin activity was evaluated using RBC hemolytic test. Eventually, evaluation of Fra C cytotoxicity and apoptosis were performed using MTT and flow cytometery assays, respectively. Our results revealed that Fra C toxin decreased K562 cells viability in a dose- and time-dependent manner with a whole destroy of cancer cells at 35 µg ml-1 after 72 hours. Furthermore, flow cytometery analysis indicated that Fra C toxin enhanced necrosis along with apoptosis in K562 cells in a dose dependent manner. We speculate that Fra C toxin can be considered as a novel candidate for cancer cell researches and treatments providing that turning it to a specific agent by engineering and directing to cancer cell membrane.