[ad_1]
While many of us have experienced painful encounters with the pointed end of a bee, its weapons could be more than just an annoyance. A new lab study shows that a molecule found in bee venom can suppress the growth of particularly nasty cancer cells.
The study focused on certain subtypes of breast cancer, including triple negative breast cancer (TNBC), which is an extremely aggressive condition with limited treatment options.
TNBC accounts for up to 15 percent of all breast cancers. In many cases, your cells make more of a molecule called EGFR than is seen in normal cells. Previous attempts to develop treatments that specifically target this molecule have not worked, because they would also adversely affect healthy cells.
BeeApis mellifera) the venom has shown potential in other medical therapies, such as the treatment of eczema, and has been known for some time to have antitumor properties, including melanoma. But how it works against tumors at the molecular level is not fully understood. Now, we have taken a big step towards the answer.
Bees actually use melittin, the molecule that makes up half of their venom and makes their stings really painful, to fight their own pathogens. Insects produce this peptide not only in their venom, but also in other tissues, where it is expressed in response to infections.
With their sights set on this powerful molecule, the researchers subjected cancer cells and normal cells grown in the laboratory to bee venom from Ireland, England, and Australia, and the bumblebee (Bombus terrestris) poison from England.
They found that bumblebee venom, which does not contain melittin but has other potential cell killers, had little effect on breast cancer cells, but bee venom from all places made a difference.
“The venom was extremely potent,” said medical researcher Ciara Duffy of the Harry Perkins Institute for Medical Research. “We found that melittin can completely destroy the membranes of cancer cells in 60 minutes.”
When melittin was blocked with an antibody, cancer cells exposed to bee venom survived, showing that melittin was in fact the component of the venom responsible for the results of previous trials.
The best part: Melittin had little impact on normal cells, specifically targeting cells that produced a lot of EGFR and HER2 (another molecule overproduced by some types of breast cancer); it even spoiled the replication capacity of cancer cells.
“This study demonstrates how melittin interferes with signaling pathways within breast cancer cells to reduce cell replication,” said Western Australian chief scientist Peter Klinken, who was not involved in this study.
Taking their conclusions even further, the research team also produced a synthetic version of melittin, to see how it would perform compared to the real business.
“We found that the synthetic product reflected most of the anticancer effects of bee venom,” Duffy said.
Then Duffy and his team tested the action of melittin combined with chemotherapy drugs in mice. The experimental treatment lowered levels of a molecule that cancer cells use to evade detection by the immune system.
“We found that melittin can be used with small molecules or chemotherapies, such as docetaxel, to treat highly aggressive types of breast cancer,” explained Duffy. “The combination of melittin and docetaxel was extremely effective in reducing tumor growth in mice.”
EGFR and HER2 overexpression is also seen in other types of cancers, such as lung cancer, and these results suggest that they could also be potential targets for melittin.
Of course, many things can kill a cancer cell in a Petri dish, and the researchers caution that there is still a long way to go before this bee venom molecule can be used as a treatment in humans.
“Future studies will be required to formally evaluate the toxicities and maximum tolerated doses of these peptides prior to human trials,” they wrote in their paper.
But this formidable weapon of insects provides another incredible example of chemicals found in nature that could also be useful for human disease. However, we must remember that, like so many other creatures, bees face significant health threats.
This research was published in Natural precision oncology.
