Image: Kathy Jones, Wikimedia Commons

The venom in Brazilian wasps’ stingers has been proven to attack cancerous cells while leaving normal cells alone — and scientists now know why. 

Brazilian wasps (Polybia paulista) are highly social insects that persist throughout areas of Brazil, Paraguay, and Argentina, specifically the São Paulo area.

The toxin in their stingers, identified as Polybia-MP1 (MP1), is capable of targeting and attacking cancer cells while leaving healthy cells alive. Researchers have been actively studying the mechanism behind this selection process and can now attribute it to their action upon lipids in cell membranes.

MP1 effectively disrupts the arrangement of fats in cell membranes and consequently creates weak points throughout the surface. The toxin eventually breaks through the membrane entirely, forming small holes through which leak out essential cell bodies, including proteins, without which the cell can no longer function.

Image: Mauro Guanandi, Flickr

The toxin is specifically effective on phospholipids phosphatidylserine (PS) and phosphatidylethanolamine (PE) which are located on the outer part of the membrane of cancerous cells.

The full study is published in the Biophysical Journal.

Researchers found that the presence of PS increased the binding of MP1 to the membrane by a factor of 7 to 8 and the presence of PE significantly improved the toxin’s ability to break down the lipid structures, attributing to 20-30 times bigger holes.

 

Image: Wikimedia Commons
Image: Wikimedia Commons

Further study and detailed analysis of these processes could result in venom’s eventual use in a clinical setting as a chemotherapeutic agent.

“Understanding the mechanism of action of this peptide will help in translational studies to further assess the potential for this peptide to be used in medicine,” study co-author Paul Beales explained. “As it has been shown to be selective to cancer cells and non-toxic to normal cells in the lab, this peptide has the potential to be safe, but further work would be required to prove that.”