Melittin is a PLA₂ activator, stimulates the activity of the low molecular weight PLA₂, while it does not the increase activity of the high molecular weight PLA₂. IC50 & Target: PLA₂^[1] In Vitro: Melittin, an immunologically related PLA₂ stimulating peptide from bee venom, increases the activity of the high molecular weight enzyme^[1]. Melittin is a cytotoxic peptide from bee venom. Melittin exhibits toxicity against both A2780CR and A2780 cells, with IC₅₀ values of 4.5 and 6.8 μg/mL, respectively. Melittin has natural anti-bacterial, anti-viral, and anti-inflammatory properties. It has also been shown to have diverse anticancer effects in several different cancer cell lines including those of gastric, breast, ovarian, liver, prostate, cervical, and lung origins. The mechanisms by which Melittin, an amphipathic haemolytic peptide, exerts its potential anticancer effects include inhibition of cell proliferation, induction of apoptosis, and direct necrosis. Melittin can also prevent EGF-induced cell invasion through its inhibition of the PI3K/Akt/mTOR signaling pathway, but this is primarily related to breast cancer cells^[2].