Manuka honey reduced breast cancer cell growth by 84% without harming healthy cells or causing major side effects, according to preliminary studies. The findings open the door to developing a natural, non-toxic supplementary, or potentially stand-alone, anticancer treatment.
Nutraceuticals – a combination of ‘nutrition’ and ‘pharmaceuticals’ that, let’s be honest, smacks of marketing speak – are products that, apart from providing nutritional value, also have health-improving properties. Ginseng, green tea, Echinacea, and omega-3 are common examples. So is Manuka honey, produced from the nectar collected by honey bees when they pollinate the mānuka, a species of tea tree indigenous to New Zealand and southeast Australia.
Manuka honey has been demonstrated to have antibacterial, antioxidant and healing properties that are thought to be due to its specific composition, which differs from other kinds of honey. Now, preliminary studies by researchers at UCLA have found that this nutraceutical might aid in breast cancer prevention and treatment.
“The findings provide hope for [the] development of a natural, less toxic alternative to traditional chemotherapy,” said Dr Diana Márquez-Garbán, associate professor of medicine at the UCLA David Geffen School of Medicine, and the study’s lead author. “Although more research is necessary to fully understand the benefits of natural compounds in cancer therapy, this study establishes a strong foundation for further exploration in this area.”
In those diagnosed with estrogen receptor (ER) positive breast cancer – which is about 60% to 70% of people diagnosed with breast cancer – the cancer cells have receptors that allow them to use the hormone estrogen to grow. While treatment with anti-estrogen, or endocrine, therapy can block tumor growth in most patients, some become resistant to the treatment, often leaving potentially toxic chemotherapy as the only alternative.
The researchers first grew ER-positive and triple-negative breast cancer cells, another of the most common types of breast cancer, in the lab. In the ER-positive cells treated with Manuka honey or dehydrated Manuka honey powder, they observed a significant dose-dependent inhibition of cancer cell proliferation compared to those treated with controls. For the triple-negative cells, the antitumor effect was more modest. When Manuka honey was combined with tamoxifen, a drug widely used as an anti-estrogen therapy, ER-positive cell proliferation was markedly suppressed and significantly less than that of either treatment administered alone.
Examining the cells more closely, the researchers found that the honey caused a reduction in blood estrogen levels and estrogen receptors in the tumors and further disrupted cancer progression by inducing apoptosis, or cell death, in the tumor cells.
They then moved on to testing Manuka honey in animal models. Mice that had been implanted with human ER-positive breast cancer cells and developed a tumor were given Manuka honey orally. The honey-treated mice showed significantly suppressed tumor growth compared to controls. Overall, it inhibited the growth and progression of an established human breast cancer tumor by 84% without affecting healthy cells.
“These findings indicate that natural compounds such as Manuka honey, with significant antitumor activity and selectivity towards hormone receptor-positive breast cancers, may be further developed as a supplement or potential alternative to cytotoxic anticancer drugs that have more non-selective adverse effects,” the researchers concluded.
The study was published in the journal Nutrients.
Source: UCLA Health