Melatonin helps to promote restful sleep. Can it also be helpful in shrinking breast cancer cells?
Breast cancer is the most common type of cancer among women. Today, this type of cancer generally has a good prognosis: around 80% of women have a survival rate of 10 years or longer. This is partially due to the chemotherapeutic agent known as tamoxifen.
Tamoxifen is the leading medication that is used to treat breast cancer. It prevents breast cancer cells from multiplying in hormone-receptor positive cancers by hindering the effects of estrogen. Yet, despite its popularity, tamoxifen triggers some severe side effects. It can cause vision problems, hot flashes, weight loss, as well as increase the risk for stroke, uterine cancer, and pulmonary embolism. There is also the problem of chemoresistance. Some cancer cells can get accustomed with tamoxifen and become resistant to it. With time, the medication will become less effective and ultimately stop working altogether.
Now, researchers are looking into the use of melatonin as a powerful adjuvant to tamoxifen. Melatonin is a hormone that is found naturally in the body. Taken as a medication, it is used to adjust the body’s internal clock and to establish a day and night cycle. Melatonin is used for jet lag, insomnia, insomnia associated with attention deficit-hyperactivity disorder, rapid eye movement sleep behavior disorder, delayed sleep phase syndrome, and other types of sleep problems. Recent research also shows that melatonin can help to keep breast cancer at bay, by supporting a process called apoptosis or programmed cell death.
An overlooked option for breast cancer?
Melatonin interacts with linoleic acid, which is a type of dietary fat that is known to stimulate breast cancers. In a recent study conducted at Bassett Research Institute in Cooperstown, researchers injected the nighttime hormone in mice models implanted with human breast cancers. “This breast cancer rev-up mechanism gets revved down by melatonin. Nighttime melatonin is a relevant anticancer signal to human breast cancers. Ninety percent of human breast cancers have specific receptors for this signal” said David E. Blask, lead researcher of the study.
Melatonin comes out from a small gland in the brain, known as the pineal gland. The pineal gland receives information from the retinas and pays close attention to the levels of light. According to these levels, it can determine whether it is day or night. This is the reason why the body becomes sleepy when it is dark. The pineal gland signals the body to naturally produce melatonin and in turn, the hormone informs the body when it is time to go to bed.
Therefore, Blask and his fellow colleagues hypothesized that melatonin can put breast cancer cells to sleep as well, and slow down tumor growth by 70%. They exposed the mice models with human breast cancers to constant light and found that tumor growth went way up. “With constant light, tumors grow seven times faster and soak up incredible amounts of linoleic acid. During the day, the cancer cells are awake and linoleic acid stimulates their growth. But at night cancer cells go to sleep. When we turn on lights at night for a long time, we suppress melatonin and revert back to the daytime condition” said Blask.
Seeing as how a majority of cancer patients suffer from sleep problems, the research team suggested that melatonin may improve the quality of life in cancer patients by helping them to get some well-needed rest.
A real and positive impact
For Bonnie Annis, a breast cancer survivor, sleep was never a problem until after she had undergone breast cancer surgery. “On my first night home, I found myself tossing and turning as I tried to get comfortable. Forced to sleep uncomfortably on my back because of my recent mastectomies, sleep took its time coming. Since that day, my nights have been difficult, and I’ve continued having trouble sleeping” she said.
After consulting with her doctor, he suggested that Annis try taking melatonin – a 5 milligram dose. “It seemed to work for a while, but then I started waking in the middle of the night. The doctor suggested I increase the dosage to 10 milligrams and so far, it’s been working well to help me sleep through the night” she said.
For the past 4 years, Annis has continued to take melatonin to promote a healthy sleeping pattern. However, it wasn’t until recently that she learned the medication may be able to help shrink breast cancer cells. Seeing as how melatonin helps to control estrogen, progesterone, and testosterone; this led Annis to wonder if the medication may be beneficial in preventing breast cancer from returning. “I have read some online medical articles that seem to indicate this may be the case. Melatonin has been shown to reduce the levels of circulating estrogen. This in turn can help slow down the growth of breast tumors, and may possibly reduce the incidence of breast cancer” she said.
For those who are having difficulty getting a good night’s sleep, especially during or after breast cancer treatments, Annis recommends asking an oncologist about the benefits and risks of melatonin based on each individual’s case. “I’ve decided to continue taking melatonin for the rest of my life as part of my alternative healing therapy regimen for breast cancer. Since it is a natural hormone produced by my body, I don’t fear taking the supplement in fact, I consider myself proactive in doing everything I can to protect myself from a recurrence of breast cancer” she said.
A medication worth looking into
To date, there are several studies that indicate melatonin may be helpful in shrinking breast cancer cells, yet further studies are necessary before deriving to any accurate conclusions. What has been demonstrated through some epidemiological studies is that women working swing/night shifts, such as nurses, are at an increased risk of developing breast cancer.
Due to its efficiency in patients with various cancers, like breast cancer, coupled with its low toxicity profile, melatonin may be beneficial for breast cancer recurrence. Researchers are continuously trying to find new approaches to increase the efficiency of chemotherapeutic agents, all the while decreasing the dose required due to unwanted side effects. That being said, the results are promising, but there is still a long way to go.