Do you have ever imagined that the painful bite of honeybee can be the medicine of the world’s deadliest disease cancer?
Yes, experts from the University of Western Australia have found that the compounds found inside honeybee venom can help to tackle aggressive forms of breast cancer without putting healthy cells at risk.
The finding becomes more effective as it was focused on certain subtypes of breast cancer, including triple-negative breast cancer (TNBC), which is an extremely aggressive condition with limited treatment options.
According to the lead researcher, Dr Ciara Duffy, “melittin” in the right concentrations can kill up to 100 per cent of cancer cells without having an effect on normal cells within 60 minutes.
Melittin – is the molecule that makes up half of the Bee venom and makes their stings really hecking painful to fight off their own pathogens. The insects produce this peptide not just in their venom, but in other tissues too, where it’s expressed in response to infections.
Melittin in honeybee venom also had another remarkable effect; within 20 minutes, it was able to substantially reduce the chemical messages of cancer cells that are essential to cancer cell growth and cell division.
The team had used venom from 312 bees found in Perth, Western Australia, Ireland and England as part of the research.
TNBC accounts for up to 15 percent of all breast cancers. In many cases, its cells produce more of a molecule called EGFR than seen in normal cells. Previous attempts to develop treatments that specifically target this molecule have not worked, because they would also negatively affect healthy cells.
Honeybee (Apis mellifera) venom has shown potential in other medical therapies such as treating eczema, and has been known to have anti-tumour properties for some time now, including melanoma. But how it works against tumours at a molecular level isn’t fully understood. Now, we’ve taken a huge step closer to the answer.
Researchers used lab-grown cancer cells and normal cells to honeybee venom from Ireland, England, and Australia, and to bumblebee (Bombus terrestris) venom from England.
They found bumblebee venom – which doesn’t contain melittin, but has other potential cell-killers – had little effect on breast cancer cells, but the honeybee venom from all locations did make a difference.
When melittin was blocked with an antibody, the cancer cells exposed to the bee venom survived – showing that melittin was indeed the venom component responsible for the results in the earlier trials.
The best part: melittin had little impact on normal cells, specifically targeting cells that produced a lot of EGFR and HER2 (another molecule excessively produced by some breast cancer types); it even messed with the cancer cells’ ability to replicate.
Further experiments with Melittin
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 deal.
Dr Duffy also tested to see if melittin could be used with existing chemotherapy drugs as it forms pores, or holes, in breast cancer cell membranes, potentially enabling the entry of other treatments into the cancer cell to enhance cell death.
‘We found that melittin can be used with small molecules or chemotherapies, such as docetaxel, to treat highly-aggressive types of breast cancer. The combination of melittin and docetaxel was extremely efficient in reducing tumour growth in mice.’
As part of the study, Duffy and colleagues had to put bees to sleep with carbon dioxide and kept them on ice until the venom barb could be pulled out.
While there are 20,000 species of bees, Dr Duffy wanted to compare the effects of Perth honeybee venom to other honeybee populations in Ireland and England, as well as to the venom of bumblebees.
There is no doubt that during research many things can kill a cancer cell. But there is a long procedure and experiments through which it has to go before this bee venom molecule could potentially be used as a treatment in humans.
“Future studies to formally assess toxicities and maximum tolerated doses of these peptides will be required prior to human trials,” they wrote in their paper.
Breast cancer is one of the most common cancers in the world. Each year in the UK there are more than 55,000 new cases, and the disease claims the lives of 11,500 women. In the US, it strikes 266,000 each year and kills 40,000.
Breast cancer is a type of cancer that starts in the breast. Cancer starts when cells begin to grow out of control. Breast cancer cells usually form a tumour that can often be seen on an x-ray or felt as a lump. Breast cancer occurs almost entirely in women, but men can get breast cancer, too.
The reasons for breast cancer
A cancerous tumour starts from one abnormal cell. The exact reason why a cell becomes cancerous is unclear. It is thought that something damages or alters certain genes in the cell. This makes the cell abnormal and multiplies ‘out of control’.
Although breast cancer can develop for no apparent reason, there are some risk factors that can increase the chance of developing breast cancer, such as genetics.
What are the symptoms of breast cancer?
- The usual first symptom is a painless lump in the breast, although most breast lumps are not cancerous and are fluid-filled cysts, which are benign.
- The first place that breast cancer usually spreads to is the lymph nodes in the armpit. If this occurs you will develop a swelling or lump in an armpit.
Types of treatments for breast cancer
- Surgery: Breast-conserving surgery or the removal of the affected breast depending on the size of the tumour.
- Radiotherapy: A treatment which uses high energy beams of radiation focussed on cancerous tissue. This kills cancer cells or stops cancer cells from multiplying. It is mainly used in addition to surgery.
- Chemotherapy: A treatment of cancer by using anti-cancer drugs which kill cancer cells, or stop them from multiplying
- Hormone treatments: Some types of breast cancer are affected by the ‘female’ hormone oestrogen, which can stimulate the cancer cells to divide and multiply. Treatments which reduce the level of these hormones, or prevent them from working, are commonly used in people with breast cancer.