Home page News Related Researches 2000-2009

Melatonin: An Endogenous Antiestrogen with Oncostatic Properties

Published on Friday, 02 January 2026

Abstract

Melatonin inhibits the growth of breast cancer cells by interacting with estrogen- responsive pathways, thus behaving as an antiestrogenic hormone.

In this article we will review the evidence supporting three different kinds of melatonin antiestrogenic effects:

a) the downregulation of the gonadal synthesis of estrogens, thus giving a reduction in the circulating levels of gonadal steroids;

b) the interaction with the estrogenic receptors, in a similar way to the so called selective estrogen receptors modulators (SERMs), although by means of a different mechanism;

c) the inhibition of the enzymes involved in the biosynthesis of estrogens in peripheral tissues, mainly the aromatases, allowing melatonin to be considered as a selective estrogen enzyme modulator (SEEMs).

We conclude that melatonin, because of the wide range of its antiestrogenic actions could be a valuable instrument in the prevention and treatment of hormone-dependent mammary tumors, either alone, or in combination with other SERMs and SEEMs drugs which share properties with melatonin but have different action mechanisms.

Download the complete article

About this chapter from the book Melatonin: From Molecules to Therapy.

The Di Bella's Method: Use Melatonin, Retinoids (40mg per day Beta-Carotene, 10mg per day ATRA and 10mg per day Axerophthol palmitate), Estrogen therapy (Anastrozole 1 mg tab per day), pseudo-Metronomic Chemotherapy Cyclophosphamide and/or Hydroxyurea, Somatostatin/Octreotide analogues and/or derivatives with Cabergoline and/or Bromocriptine (together with others chemical compounds) in Breast Cancer:

- A retrospective observational clinical study of triple negative breast cancer cases treated with Di Bella Method: A preliminary data;

- The Synergism of Somatostatin, Melatonin, Vitamins Prolactin and Estrogen Inhibitors Increased Survival, Objective Response and Performance Status In 297 Cases of Breast Cancer;

- Complete objective response, stable for 5 years, with the Di Bella Method, of multiple-metastatic carcinoma of the breast;

- Evaluation of the safety and efficacy of the first-line treatment with somatostatin combined with melatonin, retinoids, vitamin D3, and low doses of cyclophosphamide in 20 cases of breast cancer: a preliminary report;

- The Di Bella Method (DBM) improved survival, objective response and performance status in a retrospective observational clinical study on 122 cases of breast cancer;

- Complete objective response to biological therapy of plurifocal breast carcinoma;

- The Di Bella Method (A Fixed Part - Melatonin tablets. From 30-40mg/day up to 200mg/day and more orally in patients with advanced stage of cancer disease and/or patients without respond to traditional treatments);

- Melatonin use in cancer patients have started in 1974, when melatonin prepared according to Prof. Di Bella’s formulation [...]. For 11 days was administered to the patient, admitted to the general medical ward at the Maggiore-Pizzardi Hospital in Bologna, very slowly (over approx. 8 hours) and intravenously administered 1000 mg of melatonin for 11 days. During the course of each day, the patient was intravenously administered 4 saline drips of 500 ml, each containing ten 25 mg bottles of freeze-dried melatonin, lasting 2 hours, totaling 1000 mg per day. No other drug of any kind was administered in order to ascertain the effect of the MLT without interference [...]. From Melatonin with adenosine solubilized in water and stabilized with glycine for oncological treatment - technical preparation, effectivity and clinical findings;

- About Melatonin - In vitro, review and in vivo publications;

- Publication: Melatonin anticancer effects: Review (from Di Bella's Foundation);

- Publication: Key aspects of melatonin physiology: 30 years of research (from Di Bella's Foundation);

- The Di Bella Method (A Fixed Part - Calcium, 2 grams per day, orally);

- The Di Bella Method (A Fixed Part - Somatostatin, Octreotide, Sandostatin LAR, analogues and/or derivatives);

- Somatostatin in oncology, the overlooked evidences - In vitro, review and in vivo publications;

- Publication, 2018 Jul: Over-Expression of GH/GHR in Breast Cancer and Oncosuppressor Role of Somatostatin as a Physiological Inhibitor (from Di Bella's Foundation);

- Publication, 2018 Sep: The over-expression of GH/GHR in tumour tissues with respect to healthy ones confirms its oncogenic role and the consequent oncosuppressor role of its physiological inhibitor, somatostatin: a review of the literature (from Di Bella's Foundation);

- Publication, 2019 Aug: The Entrapment of Somatostatin in a Lipid Formulation: Retarded Release and Free Radical Reactivity (from Di Bella's Foundation);

- Publication, 2019 Sep: Effects of Somatostatin and Vitamin C on the Fatty Acid Profile of Breast Cancer Cell Membranes (from Di Bella's Foundation);

- Publication, 2019 Sep: Effects of somatostatin, curcumin, and quercetin on the fatty acid profile of breast cancer cell membranes (from Di Bella's Foundation);

- Publication, 2020 Sep: Two neuroendocrine G protein-coupled receptor molecules, somatostatin and melatonin: Physiology of signal transduction and therapeutic perspectives (from Di Bella's Foundation);