The venom kills the cancer cells but does not affect healthy cells:

The wasp Polybia paulista protects itself against predators by producing venom known to contain a powerful cancer-fighting ingredient. A Biophysical Journal study published September 1 reveals exactly how the venom's toxin—called MP1 (Polybia-MP1)—selectively kills cancer cells without harming normal cells. MP1 interacts with lipids that are abnormally distributed on the surface of cancer cells, creating gaping holes that allow molecules crucial for cell function to leak out.

"Cancer therapies that attack the lipid composition of the cell membrane would be an entirely new class of anticancer drugs," says co-senior study author Paul Beales, of the University of Leeds in the UK. "This could be useful in developing new combination therapies, where multiple drugs are used simultaneously to treat a cancer by attacking different parts of the cancer cells at the same time."

MP1 acts against microbial pathogens by disrupting the bacterial cell membrane. Serendipitously, the antimicrobial peptide shows promise for protecting humans from cancer; it can inhibit the growth of prostate and bladder cancer cells, as well as multi-drug resistant leukemic cells. However, until now, it was not clear how MP1 selectively destroys cancer cells without harming normal cells.

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