Biochemotherapy with immunomodulating pineal hormones other than melatonin: 5-methoxytryptamine as a new oncostatic pineal agent.

Several experiments have demonstrated that pineal gland plays a physiological anticancer role. Melatonin (MLT), its most investigated hormone, is a natural anticancer agent. However, MLT would not be the only endocrine molecule responsible for the anticancer property of the pineal gland. In fact, another pineal indole hormone, the 5-methoxytryptamine (5-MTT), has appeared to exert in vitro an antitumour activity superior to that of MLT itself. Previous studies have already shown the therapeutic anticancer action of MLT in association with chemotherapy also in human neoplasms. This study was performed to evaluate the influence of 5-MTT at physiological doses (1 mg/day orally during light phase) on the efficacy of chemotherapy with cisplatin plus etoposide in advanced non-small cell lung cancer patients with respect to that obtained in patients treated by chemotherapy alone or chemotherapy plus pharmacological doses of MLT (20 mg/day orally during the dark phase of the day). The study included 100 patients, who were randomised to receive chemotherapy alone or in association with MLT or 5-MTT. The overall response rate achieved in both patients concomitantly treated with MLT or 5-MTT was significantly higher with respect to that obtained in patients treated with chemotherapy alone. Moreover, both MLT and 5-MTT significantly reduced some chemotherapy-related toxicities, namely thrombocytopenia and neurotoxicity. This preliminary study shows that less known pineal hormone 5-MTT may exert at low doses the same anticancer therapeutic effect in association with chemotherapy, which may be obtained by pharmacological doses of the most investigated pineal hormone MLT.