Healing Strategies:
What to Subtract
Healing Strategies:
What to Add
Breastcancerchoices.org
Innovative Research and Patient Advocacy
Your Donation  Helps
Our Research And
Advocacy Programs

Your Donation is Tax
Deductible
Please Make
Checks Payable to:

Breast Cancer
Choices, Inc.
PO Box 1567
Amagansett, NY
11930

Supplement Strategy: Melatonin

Melatonin, a hormone produced in the pineal gland located in the brain, is well
known for its role in the regulation of the sleep/wake cycles. Several studies indicate
that melatonin levels may be linked with breast cancer risk, because many women
with breast cancer tend to have lower levels of melatonin than those without the
disease. In addition, laboratory experiments have found that low levels of melatonin
stimulate the growth of certain types of breast cancer cells and adding melatonin to
these cells inhibits their growth. Thus, the supplement,melatonin, is widely
recommended because it has several beneficial mechanisms of action.






  • High number of women with estrogen receptor positive tumors have low
    levels of melatonin in their blood.

  • Melatonin appears to work as an anti-estrogen on tumor cells.although
    differently than Tamoxifen. When the two are combined, the result is better
    than Tamoxifen alone. (Lissoni et`al., 1995.

  • A 2006 study showed Melatonin may work as a kind of aromatase inhibitor.
    (Cos et al.)

  • Low levels of melatonin have been associated with breast cancer occurrence
    and development. Women who work predominantly at night and are exposed
    to light, which inhibits melatonin production and alters the circadian rhythm,
    have an increased risk of breast cancer development (Schernhammer et al.
    2003).

  • The circadian rhythm alone is a  significant predictor of survival time for breast
    cancer patients (Sephton et al. 2000).

  • Melatonin demonstrates growth inhibitory effects by inducing differentiation
    (“normalizing” cancer cells)(Cos et al. 1996) as well directly inhibits breast
    cancer cell proliferation (Ram et al. 2000) and  boosting the production of
    immune components, including natural killer cells (NK cells) that have an
    ability to kill metastasized cancer cells.

 Melatonin can be safely taken for an indefinite period of time. The
suggested dose of melatonin for breast cancer patients is 3-50 mg at
bedtime.  Some people initially experience vivid dreams or morning
drowsiness. To avoid these minor side effects melatonin may be taken in
low doses nightly and the dose slowly increased over a period of several
weeks. Consult your doctor before starting this or any supplement.


Interesting research on Melatonin

Epidemiology. 2006 Jan;17(1):108-11.

Night work and risk of breast cancer.

Schernhammer ES, Kroenke CH, Laden F, Hankinson SE.

Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard
Medical School, Boston, Massachusetts 02115, USA. eva.schernhammer@channing.harvard.edu

BACKGROUND: Melatonin shows potential oncostatic activity and is acutely suppressed by light
exposure. Some evidence suggests an association between night work and breast cancer risk,
possibly through the melatonin pathway. METHODS: In a cohort of premenopausal nurses, we
prospectively studied the relation between rotating night shift work and breast cancer risk. Total
number of months during which the nurses worked rotating night shifts was first assessed at baseline
in 1989 and periodically updated thereafter. We used Cox proportional hazards models to
calculate relative risks (RRs) and 95% confidence intervals (CIs). RESULTS: Among 115,022
women without cancer at baseline, 1,352 developed invasive breast cancer during 12 years of
follow up. Women who reported more than 20 years of rotating night shift work experienced an
elevated relative risk of breast cancer compared with women who did not report any rotating
night shift work (multivariate RR = 1.79; 95% CI = 1.06-3.01). There was no increase in risk
associated with fewer years of rotating night work. CONCLUSION: Our results suggest a modestly
elevated risk of breast cancer after longer periods of rotating night work. Additional studies are
warranted to rule out small sample size or uncontrolled sources for confounding as alternative
explanations..

Melatonin increases the survival time of animals with untreated mammary tumours:
neuroendocrine stabilization.

Saez MC, Barriga C, Garcia JJ, Rodriguez AB, Masot J, Duran E, Ortega E.

Department of Physiology, Faculty of Science, University of Extremadura, Badajoz, Spain.

The aim of this study was to evaluate the therapeutic effect of melatonin, the main hormone of
the pineal gland, on rats with advanced and untreated mammary tumours. Mammary tumours
were chemically induced in Sprague-Dawley rats with the carcinogen 9,10-dimethyl-1,2-
bezanthracene (DMBA). After the appearance of tumours the effect of melatonin (5 mg/ml per rat
per day) was then evaluated on the survival time, tumour multiplicity, and tumour volume until the
death of the animals. In addition, the variations in prolactin, noradrenaline and adrenaline
concentrations, and in the percentage of NK cells were evaluated after one month of the
treatment with melatonin. Daily administration of melatonin increased significantly the survival
time of tumour-bearing animals (p<0.05 with respect to the control non-melatonin-receiving rats).
The increased survival time did not correlate, however, with changes in either tumour multiplicity
or tumour growth rate. Animals with mammary tumours exhibited an increase (p<0.05 with respect
to healthy animals) in prolactin and catecholamine concentrations. The administration of
melatonin stabilized the hormone levels, returning them to those in the basal-healthy animals.
Rats with mammary tumours also presented lower percentages of NK cells, which were not
increased by the administration of melatonin. The results strongly suggest that melatonin per se is
beneficial during advanced breast cancer. It increases survival time, maybe by improving the
homeostatic and neuroendocrine equilibrium which is imbalanced during advanced breast
cancer.
-----------------------

Int J Cancer. 2006 Jan 15;118(2):274-8.

Melatonin inhibits the growth of DMBA-induced mammary tumors by decreasing the local
biosynthesis of estrogens through the modulation of aromatase activity.

Cos S, Gonzalez A, Guezmes A, Mediavilla MD, Martinez-Campa C, Alonso-Gonzalez C, Sanchez-
Barcelo EJ.

Department of Physiology and Pharmacology, School of Medicine, University of Cantabria,
Santander, Spain.

Melatonin inhibits the growth of breast cancer cells by interacting with estrogen-responsive
pathways, thus behaving as an antiestrogenic hormone. Recently, we described that melatonin
reduces aromatase expression and activity in MCF-7 human breast cancer cells, thus modulating
the local estrogen biosynthesis. To investigate the in vivo aromatase-inhibitory properties of
melatonin in our current study, this indoleamine was administered to rats bearing DMBA-induced
mammary tumors, ovariectomized (ovx) and treated with testosterone. In these castrated animals,
the growth of the estrogen-sensitive mammary tumors depends on the local aromatization of
testosterone to estrogens. Ovariectomy significantly reduced the size of the tumors while the
administration of testosterone to ovx animals stimulated tumor growth, an effect that was
suppressed by administration of melatonin or the aromatase inhibitor aminoglutethimide. Uterine
weight of ovx rats, which depends on the local synthesis of estrogens, was increased by
testosterone, except in those animals that were also treated with melatonin or aminoglutethimide.
The growth-stimulatory effects of testosterone on the uterus and tumors depend exclusively on
locally formed estrogens, since no changes in serum estradiol were appreciated in testosterone-
treated rats. Tumors from animals treated with melatonin had lower microsomal aromatase activity
than tumors of animals from other groups, and incubation with melatonin decreased the
aromatase activity of microsomal fractions of tumors. Animals treated with melatonin had the
same survival probability as the castrated animals and significantly higher survival probability than
the uncastrated. We conclude that melatonin could exert its antitumoral effects on hormone-
dependent mammary tumors by inhibiting the aromatase activity of the tumoral tissue.

These statements have not been evaluated by the U.S. Food & Drug
Administration.  The supplements discussed are not intended to diagnose, treat,
cure, or prevent any disease.
This website is intended as information only. The editors of this site are not medically-trained.
Please consult your licensed health care practitioner before implementing any health strategy.
The information provided on this site is designed to support, not replace, the relationship that
exists between a patient/site visitor and his/her existing physician. This site accepts no
advertising. The contents of this site are copyrighted 2006 by Breast Cancer Choices, Inc.
Contact us for reprint permission. Website updated January 7, 2008