Can melatonin and its metabolites boost the efficacy of targeted therapy in patients with advanced melanoma?

Despite groundbreaking new treatments such as checkpoint inhibition and targeted therapy, the overall response and survival rates are limited in patients with metastatic melanoma. Here, we hypothesize that melatonin and its metabolites could be promising boosters of the efficacy of BRAF/MEK inhibitors in patients with advanced melanoma. Melatonin, a well-known endogenous synchronizer of the circadian biorhythm has a variety of promising effects for melanoma biology. It regulates proliferation, apoptosis and oxidative phosphorylation via melatonin receptors, and receptor-independent pathways due to its lipophilicity. By means of interfering with the above cellular pathways, melatonin and related compounds may alter the cAMP-PKA-MITF axis, modulate tumor cell metabolism, affect MAPK signalling pathway thereby enhancing the suppressive effect of BRAF/MEK inhibitors on melanoma cell growth, and survival. Such findings could fuel preclinical studies and clinical studies where melatonin or its metabolites are combined with targeted therapy to better treat patients with metastatic melanoma.