Urinary 6-Sulfatoxymelatonin Levels and Risk of Breast Cancer in Postmenopausal Women

Abstract

Results from this prospective study provide evidence for a statistically significant inverse association between melatonin levels, as measured in overnight morning urine, and invasive breast cancer risk in postmenopausal women.

Melatonin triggers p53Ser phosphorylation and prevents DNA damage accumulation

“…Epidemiological studies have shown that melatonin decreases the risk of developing breast and other kinds of cancer (Kliukiene et al, 2001;Kloog et al, 2008;Schernhammer et al, 2008Schernhammer et al, , 2009Schernhammer et al, , 2009Schernhammer et al, , 2010Alpert et al, 2009). However, very little is known about the molecular mechanisms by which melatonin accomplishes its anticancer effects.…”

“…It is worthy to note that blind women produce higher levels of melatonin as their retina receives less light and therefore their pineal gland is less induced to reduce melatonin production. Two prospective control studies nested in larger cohorts have been recently published (Schernhammer et al, 2008(Schernhammer et al, , 2010. The first study, conducted within the Hormones and Diet in the Etiology of Breast Cancer Risk (ORDET) cohort, tested the concentration of a melatonin metabolite, 6-sulfatoxymelatonin (aMT6s) in 178 postmenopausal women with incident breast cancer and in 710 matched controls (Schernhammer et al, 2010).…”

“…The first study, conducted within the Hormones and Diet in the Etiology of Breast Cancer Risk (ORDET) cohort, tested the concentration of a melatonin metabolite, 6-sulfatoxymelatonin (aMT6s) in 178 postmenopausal women with incident breast cancer and in 710 matched controls (Schernhammer et al, 2010). The second case-control study was within the National Health Interview Survey (NHIS) cohort (Schernhammer et al, 2008). Both studies show a strong inverse association between breast cancer and overnight urinary melatonin levels of aMT6s.…”

Sleep duration and the risk of breast cancer: the Ohsaki Cohort Study

“…A lower melatonin level was associated with an increased risk of breast cancer (Schernhammer and Hankinson, 2005;Schernhammer et al, 2008). Melatonin may have an inhibitory effect on gonadal function, including the synthesis and secretion of sex hormones, by promoting the release of gonadaotropin-releasing hormone (Martin and Klein, 1976;Aleandri et al, 1996); it also exerts an antiproliferative effect on breast cancer cell lines (Blask et al, 1997).…”

Work at night and breast cancer – report on evidence-based options for preventive actions

“…Four out of five prospective cohort studies among women without night work have shown increased risk of breast cancer related to low urine levels of the melatonin metabolite, 6-sulfatoxymelatonin in morning spot samples or 24 hour samples (12)(13)(14)(15)(16). Unfortunately there are only few studies that in some detail outline the melatonin exposure profile (peak, amplitude, duration, timing) among people working night shifts (17)(18)(19)(20) except among nurses working in fastforward-rotating shifts (21).…”