For many years, strenuous research has been on-going in the pursuit of finding cures for cancer. With our efforts, we have generated different drugs which specifically target cancer cells while excluding normal healthy cells. In parallel, researchers have also looked into the natural cancer therapeutics nature has to offer, such as those made by bacteria and plants. As well, an interesting endeavour by a small group of researchers from both Brazil and UK has also shown that compounds made by insects may also provide anti-cancer drugs. Specifically, the group looked into the mysterious world of Brazilian wasp venom which show promise in cancer therapeutics.
These wasps produce a venom called MP1, which has been previously studied, however outside
the context of cancer research. It was previously shown that MP1 has bactericidal activities that are able to destroy different types of bacteria in our blood without exhibiting harm/toxicity to our blood cells. Interestingly, MP1 attacks also attacks damaged immune cells in our blood, but not healthy ones.
Cells are organisms enclosed by a ‘lipid bilayer’ which acts as a protective sheath which
separates the cellular interior from its surrounding environment. Being a bi-layer, this sheath has an inner and an outer component, which are marked by characteristic components. For instance, the inner component of this bilayer is composed of specific fat molecules including phosphotidylethanolamine (PE) and phosphotidylserine (PS). PE and PS are usually found on the inner membrane but are flipped over to the outer portion when the cell encounters problems which signal cell death. This becomes a key component to for MP1 to target cancer cells.
What the Beales group were able to do was figure the mechanism by which MP1 selectively
targets cancerous cells over healthy cells. They figured out that PE and PS work together to bind and cause pores in cancer cells by coordinating recruitment of MP1 to the bilayer, respectively. It is not enough for individual specific lipids to be present by itself on the outer membrane, both PS and PE need to be present to coordinate the binding step and then the pore forming step. By this mechanism, pores on the bilayer disrupt the integrity to therefore induce cancer cell death.
The action of this Wasp venom component shows the potential to become an important cancer
therapeutic due to its selectively against cancer cell over healthy cell. It is interesting to know that, small changes in the cells bilayer may infer important information on developing and targeting of drugs to treat cancer. Who knew, a feared insect of this world contains one of the worlds hidden gems of cancer therapeutics.
Leite, N. B. et al. PE and PS Lipids Synergistically Enhance Membrane Poration by a Peptide
with Anticancer Properties. Biophys. J. 109, 936–947 (2015).