Australian researchers have reported that melittin – the active ingredient in honeybee venom – rapidly killed two types of aggressive breast cancer cells in laboratory studies, while leaving healthy cells unharmed.
However, their study, reported in the journal npr Precision Oncology, also found venom from bumblebees – which contains no melittin – did not kill the cancer cells, even at high concentrations.
The scientists at Perth’s Harry Perkins Institute of Medical Research and the University of Western Australia studied the effect of melittin (the molecule responsible for the painful sensation in a bee sting) on ‘triple- negative’ and ‘HER2-enriched’ breast cancers which “tend to develop resistance to existing treatments” and are “associated with the poorest outcomes”, noted medicalnewstoday.com.
Lead researcher Dr Ciara Duffy noted: “The venom was extremely potent. We found that melittin can completely destroy cancer cell membranes within 60 minutes.”
The study explained how melittin not only “punched holes” in cancer cells’ outer membranes, but within 20 minutes also “disrupted the passing of chemical messages” which cells need to grow and divide. Hence, Dr Duffy added, the cancer signalling pathways – the chemical messages that are fundamental for cancer cell growth and reproduction – were “very quickly shut down”.
The team discovered melittin does this by preventing the activation of receptors for growth factors in the cells’ membranes. One of the reasons HER2-enriched and triple-negative breast cancers grow uncontrollably is they have large numbers of these receptors.
The team also examined whether, because melittin creates holes in cell membranes, it “may also allow existing chemotherapy drugs to penetrate and kill cancer cells”.
Using a mouse model of triple-negative breast cancer, they found a combination of melittin and the drug docetaxel “proved more effective at shrinking the tumours than either docetaxel or melittin alone” – raising the potential to use this strategy to increase the efficacy or reduce the dosage of chemotherapy drugs (thereby reducing harmful side effects).
The study authors also noted honeybee venom is relatively cheap and easily obtainable globally, making it a good option for cancer treatment in countries with poorly resources health services.
Sources: npr Precision Oncology and medicalnewstoday.com