Melatonin combined with antineoplastic drugs or natural products for cancer treatment: An update.

Drug combinations have shown promise in suppressing drug resistance, improving drug efficacy, and reducing side effects in anticancer therapy. Considering that the anticancer activity of melatonin may be due to its antiproliferative, antioxidant, and immunomodulatory activities, the combined administration of this endogenous indoleamine with anticancer drugs has been extensively explored. This review provides an overview of the advances in the last five years in the anticancer activity of melatonin in combination with synthetic drugs and natural products. Papers on this topic were searched in PubMed, Google Scholar, Cochrane, and Scopus within the period 2018-2024. A total of 47 papers were retrieved showing a synergistic antitumor effect of melatonin combined with different drugs in the treatment of breast, colorectal, prostate, gastric, thyroid, and pancreatic cancer, as well as in head and neck squamous cell carcinoma, melanoma, and glioblastoma. The evidence gathered in this review will contribute to our knowledge of the use of melatonin. In addition, it may allow us to develop novel approaches to the treatment of cancer to be evaluated in preclinical and/or clinical trials.