Melatonin: A Rediscovered Antitumor Hormone? Its Relation to Surface Receptors; Sex Steroid Metabolism, Immunologic Response, and Chronobiologic Factors in Tumor Growth and Therapy

Influence of Melatonin Treatment on Emotion, Sleep, and Life Quality in Perimenopausal Women: A Clinical Study

Method

100 healthy perimenopausal women were recruited and randomly assigned to two groups, with 50 subjects in each group. In the control group, placebo was administrated daily for 3 cycles (4 weeks of treatment for 1 cycle and drug withdrawals for 1 week). The study group received 3 mg oral melatonin treatment daily in the same period of time. All subjects completed the study. We compared the uterine volume, endometrial thickness, LH (luteinizing hormone), FSH (follicle generating hormone), E2 (estradiol), and melatonin levels during daytime between the two groups before and after the study. Moreover, perimenopause syndrome, sleep, mood, and QoL were analyzed at the baseline and 3 cycles by the questionnaires of the Kupperman index, the Pittsburgh sleep quality index (PSQI), the Hamilton anxiety scale (HAMA), and the Hamilton depression scale (HAMD), as well as menopausal QoL (MENQOL), respectively. Any adverse reactions experienced by the subjects were also compared in the study. Finally, 91 participants (92%) completed the whole study, 47 and 44 in the study and control groups, respectively, and their data were considered in subsequent analyses.

Results

After therapy, the two groups were similar in the uterine volume and endometrial thickness. In contrast to the control group, the study group showed notably decreased LH and FSH levels. No notable difference was discovered in E2 and melatonin levels between the two groups in the study. Moreover, the study group exhibited a significantly lower score in the Kupperman index, PSQI, HAMA, HAMD, and MENQOL scale than the control group. Moreover, the two groups had no notable difference in adverse reactions.

Conclusion

Melatonin was a useful treatment to relieve climacteric symptoms and improve sleep, mood, and life quality in perimenopausal women without obvious adverse reactions.

Melatonin, an ubiquitous metabolic regulator: functions, mechanisms and effects on circadian disruption and degenerative diseases

The last four decades, we assist to an increasing scientific interest on melatonin, a circadian hormone, a metabolic regulator which influences not only plants' metabolism and their defense against pathogens but mostly the animals and humans' metabolic pathways, their response to circadian disruption, stress and burnout syndrome. In humans, as a hormonal regulator, produced in the pineal grand as well in mitochondria, melatonin is involved in different, complex intracellular signaling pathways, with antioxidant and immune stimulating effects, proving to act as a circadian synchronizer, as a preventive and therapeutic agent in many degenerative diseases, and especially in hormone-dependent cancers. Preclinical or clinical studies showed recently the mechanisms involved in regulating the cellular activity, its role in aging and circadian disturbances and impact on degenerative diseases. Melatonin proved to have an anti-inflammatory, antiapoptotic and powerful antioxidant effect by subtle mechanisms in mitochondrial metabolic pathways. This overview includes recent and relevant literature data related to the impact of endogenous and exogeneous melatonin on the prevention of cancer progression and treatment of various degenerative diseases. Metabolomics, an emerging new omics' technology, based on high performance liquid chromatography coupled with mass spectrometry is presented as an encouraging technique to fingerprint and realize a precise evaluation and monitoring of the turnover of melatonin and its metabolites in different pathological circumstances.

Endocrine Effects of Human Recombinant Interleukin-3 in Cancer Patients

It is known that several cytokines can exert hormonal effects. At present, no data are available about the possible influence of IL-3 on the endocrine system. In order to investigate the endocrine effects of IL-3 in humans, we have evaluated serum levels of Cortisol, β-endorphin, GH, PRL, FSH, LH, TSH and melatonin in response to intravenous injection of IL-3 at a dose of 1 mcg/kg b.w. at 6.00 p.m. The study was performed in 5 non-small cell lung cancer patients. GH increased significantly in response to IL-3. PRL showed a progressive decrease after IL-3 injection, but its variations were not statistically significant. All other hormones, including Cortisol, were not affected by IL-3. This preliminary study shows that IL-3 may exert endocrine effects in humans, which would seem at variance with previously reported results on most other cytokines.

The psychoneuroendocrine-immunotherapy of cancer: Historical evolution and clinical results

The prognosis of the neoplastic diseases depends not only on the biogenetic characteristics of cancer cells but also on the immunological response of patients, which may influence the biological features of cancer cells themselves as well as the angiogenic processes. Moreover, the immune system in vivo is under a physiological psychoneuroendocrine (PNE) regulation, mainly mediated by the brain opioid system and the pineal gland. In more detail, the anticancer immunity is stimulated by the pineal hormone melatonin (MLT) and inhibited by the opioid system, namely, through a mu-opioid receptor. Several alterations involving the pineal endocrine function and the opioid system have been described in cancer patients, which could play a role in tumor progression itself. Therefore, the pharmacological correction of cancer progression-related anomalies could contribute to control cancer diffusion, namely, the pineal endocrine deficiency and the hyperactivity of brain opioid system. In fact, the administration of pharmacological doses of the only MLT has already been proven to prolong the 1-year survival in untreatable metastatic cancer patients. Better results may be achieved by associating other pineal indoles to MLT, mu-opioid antagonists, cannabinoids, beta-carbolines. Moreover, these neuroendocrine combinations may be successfully associated with antitumor cytokines, such as interleukin (IL)-2 and IL-12, as a PNE-immune cancer therapy as well as with antitumor plants as PNE-phytotherapy of cancer in an attempt to propose possible anticancer treatments also to patients with disseminated cancer and untreatable according to the standard oncology.

Physiological and pharmacological properties of 5-methoxytryptophol

5-methoxytryptophol (5-ML) is a pineal indoleamine derived from serotonin shown to be biologically active in a number of species. This indolamine exhibits a circadian pattern synchronized with the day-night cycle with significant increases during daylight, already recognized in vertebrates. The multiplicity of physiological and endocrine functions of 5-ML is remarkable; it is involved in circadian rhythms, reproduction and sexual processes. Furthermore, a number of pharmacological benefits of 5-ML have been reported, including immunomodulatory, antitumor and antioxidative activities. However, the molecular mechanisms of these pharmacological effects remain unclear. The purpose of this article is to provide an overview on the general properties and physiological functions of 5-ML. An attempt has been made to fully document all studies performed using 5-ML. In addition, this article aims to gain insight into the current state of knowledge regarding pharmacological and therapeutic effects of this indoleamine.

Melatonin-induced methylation of the ABCG2/BCRP promoter as a novel mechanism to overcome multidrug resistance in brain tumour stem cells

Background:

Current evidence indicates that a stem cell-like sub-population within malignant glioblastomas, that overexpress members of the adenosine triphosphate-binding cassette (ABC) family transporters, is responsible for multidrug resistance and tumour relapse. Eradication of the brain tumour stem cell (BTSC) compartment is therefore essential to achieve a stable and long-lasting remission.

Methods:

Melatonin actions were analysed by viability cell assays, flow cytometry, quantitative PCR for mRNA expression, western blot for protein expression and quantitative and qualitative promoter methylation methods.

Results:

Combinations of melatonin and chemotherapeutic drugs (including temozolomide, current treatment for malignant gliomas) have a synergistic toxic effect on BTSCs and A172 malignant glioma cells. This effect is correlated with a downregulation of the expression and function of the ABC transporter ABCG2/BCRP. Melatonin increased the methylation levels of the ABCG2/BCRP promoter and the effects on ABCG2/BCRP expression and function were prevented by preincubation with a DNA methyltransferase inhibitor.

Conclusion:

Our results point out a possible relationship between the downregulation of ABCG2/BCRP function and the synergistic toxic effect of melatonin and chemotherapeutic drugs. Melatonin could be a promising candidate to overcome multidrug resistance in the treatment of glioblastomas, and thus improve the efficiency of current therapies.

A reinterpretation of the pathogenesis and cure of cancer according to the psychoneuroimmunological discoveries

The recent discoveries in the oncological researches have demonstrated that the prognosis of the neoplastic diseases depends on not only the biological characteristics of tumors, including oncogene expression and growth factor receptor activity, but also on the immune status of cancer patients. This is because the well-documented importance of the anticancer immunity in the initiation of the tumor that is mainly modulated by lymphocytes. In addition, the knowledge on the interactions between the immune and neuroendocrine systems has demonstrated that the immune responses are physiologically under a psychoneuroendocrine control. In particular, it has been confirmed that the activation of the brain opioid tone may suppress the generation of an effective anticancer immunity, whereas it is stimulated by other neuroendocrine structure, namely the pineal gland, through the release of at least two indole hormones with anticancer activity, melatonin and 5-methoxytryptamine, exerting both antiproliferative and immunostimulatory effects. By investigating the immune and neuroendocrine functions in cancer patients, it has been observed that cancer progression is associated with a progressive decline in the pineal function, which would constitute the main cancer-related endocrine deficiency, and the occurrence of the irreversible immune alterations. The most prognostically important factors would consist of a diminished endogenous production of anticancer cytokines, such as IL-2 and IL-12, as well as an abnormally enhanced secretion of cytokines provided by suppressive effect on the anticancer immunity, namely IL-14, TGF-beta, and IL-6. The psychoneuroimmunotherapeutic approach in the treatment of cancer would simply consist of the corrections of the various endocrine and immune cancer-related alterations in an attempt to re-establish the neuroimmune condition of the health status.

Expression of melatonin receptor (MT1) and interaction between melatonin and estrogen in endometrial cancer cell line

AIM

To determine the receptor subtypes of melatonin in estrogen receptor-positive endometrial cancer cell line, Ishikawa, and the influence of melatonin on chemosensitivity.

METHODS

To confirm the subtype of melatonin on Ishikawa cells, cells were treated with melatonin alone and with antagonists against melatonin receptor luzindole and 4-phenyl-2-propionamidotetralin (4-P-PDOT). Expression of MT1/MT2 mRNA was analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR). Immunocytochemistry of MT1/MT2 was also performed. The effect of melatonin against expression of MT1, MT2, and ERalpha-receptors mRNA was compared with RT-PCR. To determine whether melatonin enhances the effect of anticancer agents, chemosensitivity test was performed with or without melatonin.

RESULTS

Our study revealed that Ishikawa cells express MT1 by both RT-PCR and immunocytochemistry. In contrast, expression of MT2 mRNA was not found. Furthermore, ERalpha mRNA expression was attenuated at melatonin level of 1 x 10(-9) M. Chemosensitivity test revealed that melatonin enhanced anti-tumor effects of paclitaxel among anticancer drugs tested.

CONCLUSION

Based on the above results, MT1 receptor, but not MT2, is expressed in Ishikawa cells. It was also revealed that the cytostatic effect of melatonin is partly an action mediated by MT1 receptor, and attenuation of ERalpha expression was predicted as the mechanism of action. Clinical application of melatonin to biochemotherapy might be also expected.

Biochemotherapy with standard chemotherapies plus the pineal hormone melatonin in the treatment of advanced solid neoplasms

It is known since many years that the pineal hormone melatonin (MLT) may play anticancer activity through several mechanisms, including antiproliferative and immunostimulating effects. Moreover, it exerts an important antioxidant action. Therefore, MLT could be useful in the treatment of human neoplasms, either alone or in association with chemotherapy. The present study was performed to evaluate the influence of a concomitant MLT administration on efficacy and toxicity of several chemotherapeutic combinations in metastatic solid tumor patients, suffering from non-small cell lung cancer (NSCLC) or gastrointestinal tumors. The study included 370 patients who were randomized to receive chemotherapy alone or chemotherapy plus MLT (20 mg/day orally in the evening every day). NSCLC patients received cisplatin (CDDP) plus etoposide or CDDP plus gemcitabine. Colorectal cancer patients were treated with oxaliplatin plus 5-fluorouracil (5-FU), or weekly CPT-11 or 5-FU and folates (FA). Finally, gastric cancer patients received CDDP, epirubicin, 5-FU and FA or weekly 5-FU plus FA. The overall tumor regression rate achieved in patients concomitantly treated with MLT was significantly higher than that found in those treated with chemotherapy alone. Moreover, the 2-year survival rate was significantly higher in patients concomitantly treated with MLT. These results confirm in human the anticancer therapeutic properties of the pineal hormone MLT, which may enhance the efficacy of the standard anticancer chemotherapies.

Melatonin protects against oxidative stress caused by delta-aminolevulinic acid: implications for cancer reduction

delta-Aminolevulinic acid (ALA) is a precursor of haem. The increased concentration of ALA is typically related to acute intermittent porphyria, hereditary tyrosinemia, and lead poisoning. delta-Aminolevulinic acid produced in excess accumulates in a number of organs, causes oxidative damage, and often leads to cancer. Melatonin (N-acetyl-5-methoxytryptamine) is a well-known antioxidant, free radical scavenger, and exhibits anticarcinogenic properties. It protects DNA, lipids, and proteins from oxidative damage. The protective effects of melatonin against ALA-induced oxidation of guanine bases, lipid peroxidation, and alterations in membrane fluidity in several organs have been documented. There is an inverse relationship between melatonin and ALA concentrations in both experimental and clinical conditions of porphyria. The marked efficacy of melatonin in protecting against ALA-related oxidative stress, its oncostatic properties, and low toxicity constitute reasons to consider the use of this indoleamine as a co-treatment in patients suffering from disturbances related to ALA accumulation.

Growth Factors: Thrombopoietic Property of the Pineal Hormone Melatonin

The recent advances in the psychoneuroimmunology have suggested that the hematopoiesis may be under a neuroendocrine regulation, mainly exerted by the pineal gland. In particular, melatonin (MLT), which is the main pineal hormone, has appeared to stimulate platelet generation, probably by promoting the megakaryocyte fragmentation and modulating the cytokine network involved in platelet production. On this basis, we have evaluated the effect of pharmacological doses of MLT on platelet number in patients with persistent thrombocytopenia due to different causes. The study included 200 patients, who were randomized to receive supportive care alone or MLT at 20 mg/day orally in the evening, for al least 1 month. No MLT-related toxicity occured. Platelet mean number rapidly and significantly increased in response to MLT, and a normalization of platelet number was achieved on MLT therapy in 71/98 (72%) patients. The least responsive form of thrombocytopenia was DIC. This study shows that the pineal hormone MLT may represent a well tolerable and effective therapy of thrombocytopenia due to different pathogenetic mechanisms.

Decreased toxicity and increased efficacy of cancer chemotherapy using the pineal hormone melatonin in metastatic solid tumour patients with poor clinical status

Melatonin (MLT) has been proven to counteract chemotherapy toxicity, by acting as an anti-oxidant agent, and to promote apoptosis of cancer cells, so enhancing chemotherapy cytotoxicity. The aim of this study was to evaluate the effects of concomitant MLT administration on toxicity and efficacy of several chemotherapeutic combinations in advanced cancer patients with poor clinical status. The study included 250 metastatic solid tumour patients (lung cancer, 104; breast cancer, 77; gastrointestinal tract neoplasms, 42; head and neck cancers, 27), who were randomized to receive MLT (20 mg/day orally every day) plus chemotherapy, or chemotherapy alone. Chemotherapy consisted of cisplatin (CDDP) plus etoposide or gemcitabine alone for lung cancer, doxorubicin alone, mitoxantrone alone or paclitaxel alone for breast cancer, 5-FU plus folinic acid for gastro-intestinal tumours and 5-FU plus CDDP for head and neck cancers. The 1-year survival rate and the objective tumour regression rate were significantly higher in patients concomitantly treated with MLT than in those who received chemotherapy (CT) alone (tumour response rate: 42/124 CT + MLT versus 19/126 CT only, P < 0.001; 1-year survival: 63/124 CT + MLT versus 29/126 CT only, P < 0.001). Moreover, the concomitant administration of MLT significantly reduced the frequency of thrombocytopenia, neurotoxicity, cardiotoxicity, stomatitis and asthenia. This study indicates that the pineal hormone MLT may enhance the efficacy of chemotherapy and reduce its toxicity, at least in advanced cancer patients of poor clinical status.

Chemoneuroendocrine therapy of metastatic breast cancer with persistent thrombocytopenia with weekly low-dose epirubicin plus melatonin: a phase II study

Thrombocytopenia is a frequent complication of cancer and constitutes an absolute contraindication for chemotherapy. Recent studies have demonstrated that platelet generation may be influenced by both cytokines and neurohormones. In particular, the pineal indole melatonin has been proven to enhance platelet number in patients with thrombocytopenia due to different reasons. On this basis, we have evaluated the effects of a concomitant administration of melatonin in thrombocytopenic cancer patients undergoing chemotherapy. The study was performed in 14 metastatic breast cancer women treated by weekly epirubicin. Each cycle consisted of epirubicin at 25 mg/m2 i.v. at weekly intervals. Melatonin was given orally at 20 mg/day in the evening every day, starting 7 days prior to chemotherapy. Patients were considered as evaluable when they received at least four cycles of chemotherapy. Evaluable patients were 12/14. The induction phase with melatonin induced a normalization of platelet number in 9/12 evaluable patients, and no further platelet decline occurred in chemotherapy. Objective tumor regression was achieved in 5/12 (41%) patients. This preliminary study would suggest that melatonin may be effective in the treatment of cancer-related thrombocytopenia and to prevent chemotherapy-induced platelet decline. Until now, melatonin therapy of cancer has been generally considered as an alternative treatment to chemotherapy. In contrast, this study would suggest that melatonin may contribute to the realization of chemotherapy in metastatic cancer patients unable to tolerate the chemotherapeutic approach because of persistent thrombocytopenia.

The effect of melatonin chronic treatment upon macrophage and lymphocyte metabolism and function in Walker-256 tumour-bearing rats

Melatonin is the main hormone involved in the neuroendocrine-immune axis. It also presents antitumour activity. To evaluate the role of melatonin on the progression of Walker-256 tumour in rats we determined the effect of the hormone on some biochemical and functional aspects of macrophage and lymphocytes from cachectic rats. An important finding observed in immune cells from tumour-bearing (TB) rats is the impairment on glutamine and glucose metabolism in such cells. These changes are very similar to those observed in pinealectomized rats (PNX). The increased production of lactate and the flux of glucose through the Krebs cycle and the reduction in glutamine consumption seems to be involved in the immunosuppression presented in the TB and PNX animals. Melatonin treatment restored the changes observed in the metabolism of glucose and glutamine and stimulated the proliferation of lymphocytes from tumour-bearing rats. The results indicate that the effect of melatonin upon tumour growth involves the stimulation of the immune system by the hormone.

The validity of melatonin as an oncostatic agent

The validity of melatonin as a prominent, naturally occurring oncostatic agent is examined in terms of its putative oncostatic mechanism of action, the correlation between melatonin levels and neoplastic activity, and the outcome of therapeutically administered melatonin in clinical trials. Melatonin's mechanism of action is summarized in a brief analysis of its actions at the cellular level, its antioxidative functions, and its indirect immunostimulatory effects. The difficulties of interpreting melatonin levels as a diagnostic or prognostic aid in cancer is illustrated by referral to breast cancer, the most frequently studied neoplasm in trials regarding melatonin. Trials in which melatonin was used therapeutically are reviewed, i.e., early studies using melatonin alone, trials of melatonin in combination with interleukin-2, and controlled studies comparing routine therapy to therapy in combination with melatonin. A table compiling the studies in which melatonin was used in the treatment of cancer in humans is presented according to the type of neoplasm. Melatonin's suitability in combination chemotherapy, where it augments the anticancer effect of other chemotherapeutic drugs while decreasing some of the toxic side effects, is described. Based on the evidence derived from melatonin's antiproliferative, antioxidative, and immunostimulatory mechanisms of action, from its abnormal levels in cancer patients and from clinical trials in which melatonin was administered, it is concluded that melatonin could indeed be considered a physiological anticancer substance. Further well-controlled trials should, however, be performed in order to find the link between its observed effects and the underlying mechanisms of action and to define its significance as a therapeutic oncostatic agent.

Treatment of cancer chemotherapy-induced toxicity with the pineal hormone melatonin

Experimental data have suggested that the pineal hormone melatonin (MLT) may counteract chemotherapy-induced myelosuppression and immunosuppression. In addition, MLT has been shown to inhibit the production of free radicals, which play a part in mediating the toxicity of chemotherapy. A study was therefore performed in an attempt to evaluate the influence of MLT on chemotherapy toxicity. The study involved 80 patients with metastatic solid tumors who were in poor clinical condition (lung cancer: 35; breast cancer: 31; gastrointestinal tract tumors: 14). Lung cancer patients were treated with cisplatin and etoposide, breast cancer patients with mitoxantrone, and gastrointestinal tract tumor patients with 5-fluorouracil plus folates. Patients were randomised to receive chemotherapy alone or chemotherapy plus MLT (20 mg/day p.o. in the evening). Thrombocytopenia was significantly less frequent in patients concomitantly treated with MLT. Malaise and asthenia were also significantly less frequent in patients receiving MLT. Finally, stomatitis and neuropathy were less frequent in the MLT group, albeit without statistically significant differences. Alopecia and vomiting were not influenced by MLT. This pilot study seems to suggest that the concomitant administration of the pineal hormone MLT during chemotherapy may prevent some chemotherapy-induced side-effects, particularly myelosuppression and neuropathy. Evaluation of the impact of MLT on chemotherapy efficacy will be the aim of future clinical investigations.

The effect of melatonin on cleavage rate of C57BL/6 and CBA/Ca preimplantation embryos cultured in vitro

There is growing interest in using melatonin as a therapeutic agent for the treatment of a variety of medical conditions, including cancer, heart disease, glaucoma, stress, jet lag, and sleep disorders. In addition, melatonin is being evaluated in a clinical trial to test its efficacy as an oral contraceptive. In order to test any possible adverse effects of melatonin on preimplantation embryos, we used the mouse as a model system. Two strains of mice, a Ped fast, melatonin-deficient strain, C57BL/6, and a Ped slow strain previously found to have detectable melatonin levels at nighttime, CBA/Ca, were studied. Two cell embryos were incubated with melatonin concentrations from 10(-5) M to 10(-13) M for 48 or 72 hours and the number of cells per embryo assessed quantitatively at the end of the incubation period. We used sufficiently high levels of melatonin to mimic the pharmacological concentration used in the oral contraceptive. It was found that there was no effect of melatonin on embryos from either mouse strain at any of the concentrations tested. Our results suggest that if conception occurs while melatonin is being administered to treat a range of conditions, it would not adversely affect the embryo.

Prevention of cytokine-induced hypotension in cancer patients by the pineal hormone melatonin

Hypotension is a frequent side-effect of cancer biotherapies with cytokines. Cytokine-induced hypotension would mainly depend on the stimulation of nitric oxide (NO) production, which represents the most effective endogenous vasodilator. Moreover, it has been proven that both biological activity and toxicity of cytokines are influenced by the psychoneuroendocrine system, in particular by the pineal hormone melatonin. To investigate the possible modulatory effect of melatonin on cytokine cardiovascular toxicity, we evaluated the influence of a concomitant melatonin administration on interleukin-2(IL-2)- and tumour-necrosis-factor-alpha(TNF)-induced hypotension in advanced cancer patients. The study included 116 patients with advanced solid tumour, for whom no effective standard anticancer therapy was available, who underwent cancer biotherapy with IL-2 (3 x 10(6) IU/ day s.c. every day, 6 days/week for 4 weeks) or with TNF (0.75 mg/day i.v. for 5 days) as compassionate treatment for their disease. Patients were randomized to be treated with or without a concomitant melatonin administration (40 mg/day orally in the evening, starting 7 days prior to cytokine injection). The occurrence of hypotension was significantly less frequent in patients concomitantly treated by melatonin than in those who received the cytokine alone, during either IL-2: or TNF immunotherapy (IL-2; 11/45 versus 2/46, P < 0.05; TNF: 10/23 versus 1/12, P < 0.01). This study shows that melatonin may prevent hypotension occurring during cancer immunotherapy with IL-2 or TNF. Since the pineal hormone has appeared to inhibit the activity of NO synthase from the endothelial cells, we suggest that melatonin may prevent cytokine-induced hypotension by inhibiting NO production, which plays an essential role in inducing hypotension during IL-2 and TNF biotherapies.

Is there a role for melatonin in the treatment of neoplastic cachexia?

It is known that neoplastic cachexia shows metabolic characteristics different from other common causes of malnutrition, and that it is mainly due to an abnormal secretion of TNF, whose levels are often high in patients with advanced neoplasia. Previous clinical studies have suggested that the pineal hormone melatonin (MLT), which plays an essential role in the neuroendocrine regulation of biological systems, may improve the clinical status of advanced cancer patients and inhibit TNF secretion. To investigate the relationship between MLT, TNF and cancer-related weight loss, 100 untreatable metastatic solid tumour patients entered this study to receive either supportive care alone, or supportive care plus MLT (20 mg/day orally in the evening). Patients were observed for 3 months, and were considered evaluable when they were observed for at least 2 months. There were 86 evaluable patients, the other 14 patients having died from rapid progression of disease. The per cent of weight loss greater than 10% was significantly higher in patients treated by supportive care alone than in those concomitantly treated by MLT, with no difference in food intake (P < 0.01). Mean serum levels of TNF progressively increased in the supportive care group, but to levels that were not significantly different from pretreatment values. In contrast, TNF mean concentrations significantly decreased (P < 0.05) in patients concomitantly treated by MLT. These results suggest that the pineal hormone MLT may be effective in the treatment of the neoplastic cachexia by decreasing TNF blood concentrations.

Seasonal pattern of melatonin excretion in humans: relationship to daylength variation rate and geomagnetic field fluctuations

In order to investigate the influence of various environmental parameters on melatonin excretion, the night-time urinary melatonin excretion of 16 healthy volunteers was measured in samples collected monthly over a period of one year. No significant interindividual differences were detected in the monthly rate of change of melatonin excretion. A seasonal bimodal pattern did, however, emerge. Peak values were observed in June and November. In these months a combination of high daylength stability and low values of the vertical component of the geomagnetic field was recorded. Trough values were found in April and August-October when low daylength stability was combined with high values of the vertical component of the geomagnetic field. We propose that the daylength variation rate, and the fluctuations of the vertical component of the geomagnetic field, interact to induce the changes in melatonin secretion which signalize the different seasons in humans.

Exploring the EMF-Melatonin Connection: A Review of the Possible Effects of 50/60-Hz Electric and Magnetic Fields on Melatonin Secretion

This study analyzed the experimental data about the relationship between exposure to 50/60-Hz electric and magnetic fields (EMF) and melatonin secretion by the pineal gland. The authors report their results and discuss possible health consequences, in the light of epidemiologic data suggesting that breast neoplasms and depressive disorders might be related to EMF. The nocturnal peak of melatonin has been reported to be diminished, or time-shifted, or both, in rodents exposed to electric and/or magnetic fields. Current experimental data from primates and humans are insufficient to show that this change occurs in them. Epidemiologic studies of associations between EMF exposure and breast cancer and between EMF exposure and depressive disorders suggest that modifications of melatonin secretion could be a biologic signal of these effects. Nonetheless, changes in melatonin secretion cannot yet be considered a verified biologic explanation of any such association.

A randomized study of neuroimmunotherapy with low-dose subcutaneous interleukin-2 plus melatonin compared to supportive care alone in patients with untreatable metastatic solid tumour

Recent advances in our knowledge of psychoneuroimmune interactions involved in the control of tumour growth have shown the possibility of manipulating host anticancer defenses through a neuroimmunotherapeutic strategy. In particular, our previous studies have demonstrated that the concomitant administration of the pineal neurohormone melatonin may amplify the antitumour efficacy of interleukin-2 (IL-2) in humans. On this basis, a study was planned to investigate the influence of neuroimmunotherapy with low-dose IL-2 plus melatonin on survival time and on performance status in untreatable metastatic cancer patients. The study included 100 patients with metastatic solid tumours, for whom no standard therapy was available. They were randomized to receive IL-2 (3 x 10(6) IU/day subcutaneously for 4 weeks) plus melatonin (40 mg/day orally) or supportive care alone. Partial tumour regressions were seen in 9/52 (17%) patients treated with the immunotherapy, and in none of the patients treated with supportive care alone. The percentage of survival at 1 year was significantly higher in patients treated with IL-2 and melatonin than in those receiving the supportive care alone (21/52 versus 5/48, P < 0.005). Moreover, the performance status improved in 22/52 patients of the immunotherapy group and in only 8/48 patients treated with supportive care (P < 0.01). This study shows that cancer neuroimmunotherapy with low-dose IL-2 and the pineal hormone melatonin may prolong survival time and improve the quality of life of patients with metastatic solid tumours who do not respond to conventional therapies.

Modulation of human lymphoblastoid interferon activity by melatonin in metastatic renal cell carcinoma. A phase II study

BACKGROUND

Numerous attempts to identify active cytotoxic agents for the treatment of metastatic renal cell carcinoma (RCC) have proved disappointing. However, several recent developments in biologic therapy of neoplastic disease have substantially improved the prospects for the treatment of advanced RCC. Melatonin (MLT), a hormone regulated by the pineal gland, has been shown to act on the immune system by causing the release of cytokines from activated T-cell populations.

METHODS

A series of 22 patients with documented progressing RCC entered a trial in which the authors studied the effect of a long term regimen (12 months) with human lymphoblastoid interferon (IFN), 3 mega units (MU) intramuscularly 3 times per week, and MLT, 10 mg orally every day.

RESULTS

Twenty-one patients were evaluable for response and toxicity. There were seven remissions (33%): three complete, involving lung and soft tissue and four partial, with a median duration at the time of this writing of 16 months. Nine patients achieved stable disease, and five progressed. General toxicity was mild. Fever, chills, arthralgias, and myalgias occurred rarely. Leukopenia and hepatic enzyme elevation were modest and always reversible.

CONCLUSIONS

Response rate and toxic effects observed during this study warrant additional randomized studies to define the role of MLT's concomitant administration in the clinical response to IFN in metastatic RCC.

Relationship of nocturnal melatonin levels to duration and course of multiple sclerosis

Multiple sclerosis (MS) is the most common of the demyelinating diseases of the CNS. The clinical course and prognosis of the disease are variable. Characteristically, the illness tends to progress in a series of relapses and remissions. Over the years there is a tendency for the patient to enter a phase of slow and steady deterioration of neurologic function. In about 10%-20% of patients, the course of the disease is not punctuated by a fluctuating course, but rather by an inexorable progression from the onset. The pineal gland has been implicated recently in the pathogenesis and clinical course of MS. Since MS is generally a chronic progressive disorder, we predicted an association between duration of illness and the activity of the pineal gland. To investigate this hypothesis further, we studied nocturnal plasma melatonin levels in relation to duration of illness in a cohort of 32 MS patients (4 men, 28 women; mean age: 41.1 years; SD = 11.1; mean duration of illness: 13.1 years; SD = 12.4) randomly selected from consecutive hospital admissions to a Neurology service for exacerbation of symptoms. For the purpose of comparison, we also studied in the sample serum prolactin levels. The cohort included 7 patients in whom the duration of illness since onset of first neurological symptoms was < or = 5 years (mean: 3.0 years +/- 1.1) and a cohort of 25 patients in whom the duration of illness was > 5 years (mean: 15.6 years +/- 12.7).(ABSTRACT TRUNCATED AT 250 WORDS)

A randomized study with the pineal hormone melatonin versus supportive care alone in patients with brain metastases due to solid neoplasms

BACKGROUND

Unresectable brain metastases remain an untreatable disease. Because of its antitumor cytostatic action and its anticonvulsant effect, the pineal hormone melatonin could constitute a new effective agent in the treatment of brain metastases. The current study was performed to evaluate the effect of melatonin on the survival time in patients with brain metastases due to solid neoplasms.

METHODS

The study included 50 patients, who were randomized to be treated with supportive care alone (steroids plus anticonvulsant agents) or with supportive care plus melatonin (20 mg/day at 8:00 p.m. orally).

RESULTS

The survival at 1 year, free-from-brain-progression period, and mean survival time were significantly higher in patients treated with melatonin than in those who received the supportive care alone. Conversely, steroid-induced metabolic and infective complications were significantly more frequent in patients treated with supportive care alone than in those concomitantly treated with melatonin.

CONCLUSIONS

The pineal hormone melatonin may be able to improve the survival time and the quality of life in patients with brain metastases due to solid tumors.

Multiple sclerosis: relationship between seasonal variations of relapse and age of onset

The incidence of multiple sclerosis (MS) is age-dependent being rare prior to age 10, unusual prior to age 15, with a peak in the mid 20s. The manifestation of MS, therefore, appears to be dependent upon having passed through the pubertal period suggesting an endocrine influence on the timing of onset of the disease. Since pineal melatonin secretion progressively declines from childhood to puberty and as melatonin exerts an immunomodulating influence, we have proposed that the dramatic decline in melatonin secretion just prior to the onset of the clinical manifestations of puberty may lead to disruption of immune responses resulting in either reactivation of the infective agent or in an increased susceptibility to pubertal or post-pubertal infection. Melatonin secretion undergoes annual rhythms with a zenith in winter and declines to a nadir in the spring. Thus, the fall in melatonin secretion in the spring may account for epidemiological findings revealing a high incidence of relapse of MS in the spring. If the manifestations of MS are related to the fall in melatonin secretion in the post-pubertal period, then one would expect patients with a pubertal onset of the disease to have a higher incidence of relapses in spring than in winter. To test this hypothesis, we investigated in 51 patients the relationship between the seasonal occurrence of the last MS relapse with the age of onset of first manifestation of MS. While 9 of 22 patients (40.9%) who relapsed in spring (March-May) had the onset of MS prior to age 18, only 2 of 29 patients (6.9%) who relapsed in winter (November-February) experienced the onset of first symptoms prior to the age of 18 years (p < .005). These findings thus support the hypothesis implicating the pineal gland and melatonin secretion in the timing of onset of MS. Moreover, the findings may have clinical implications with respect to the prophylaxis of MS relapse in patients who experience seasonally-dependent exacerbation of symptoms.

Multiple sclerosis: the role of puberty and the pineal gland in its pathogenesis

Epidemiological studies demonstrate that the incidence of multiple sclerosis (MS) is age-dependent being rare prior to age 10, unusual prior to age 15, with a peak in the mid 20s. It has been suggested that the manifestation of MS is dependent upon having passed through the pubertal period. In the present communication, I propose that critical changes in pineal melatonin secretion, which occur in temporal relationship to the onset of puberty, are intimately related to the timing of onset of the clinical manifestations of MS. Specifically, it is suggested that the fall in melatonin secretion during the prepubertal period, which may disrupt pineal-mediated immunomodulation, may stimulate either the reactivation of the infective agent or increase the susceptibility to infection during the pubertal period. Similarly, the rapid fall in melatonin secretion just prior to delivery may account for the frequent occurrence of relapse in MS patients during the postpartum period. In contrast, pregnancy, which is associated with high melatonin concentrations, is often accompanied by remission of symptoms. Thus, the presence of high melatonin levels may provide a protective effect, while a decline in melatonin secretion may increase the risk for the development and exacerbation of the disease. The melatonin hypothesis of MS may explain other epidemiological and clinical phenomena associated with the disease such as the low incidence of MS in the black African and American populations, the inverse correlation with sun light and geomagnetic field exposure, the occurrence of relapses in relation to seasonal changes and fluctuations in mood, and the association of MS with affective illness and malignant disease. Therapeutically, this hypothesis implies that application of bright light therapy or the use of other major synchronizers of circadian rhythms such as sleep deprivation or application of external weak magnetic fields may be beneficial in the treatment and/or prophylaxis of relapses in the disease.

Neuroimmunotherapy with subcutaneous low-dose interleukin-2 and the pineal hormone melatonin as a second-line treatment in metastatic colorectal carcinoma

On the basis of our previous preliminary data which showed that the pineal hormone melatonin (MLT) may potentiate IL-2 activity and reduce the dose of IL-2 required to determine an effective host antitumor response, we performed a clinical study with low-dose IL-2 given once/day subcutaneously (3 million IU/day for 6 days/week for 4 weeks) in association with MLT (50 mg/day orally at 8.00 p.m. every day) as a second-line therapy in metastatic colorectal cancer patients pretreated with 5-fluorouracil. Evaluable patients were 13/14, and most of them showed disseminated liver metastases. No objective tumor regression was seen. A stabilization of disease was achieved in 4/13 patients (median duration 5+ months), and the other 9 patients progressed. Mean number of lymphocytes and eosinophils significantly increased during the treatment. Moreover, the mean increase in lymphocyte number was significantly higher in patients with stable disease than in those with progressive disease, whereas there was no difference as regards eosinophils. Serum levels of neopterin and tumor necrosis factor (TNF) significantly increased during therapy, and TNF increase was correlated to the side effects rather than to the control of cancer development. This study shows that neuroimmunotherapy with low-dose interleukin-2 and MLT, even though capable of determining an evident expansion of immune cells involved in host antitumor response, does not seem to be effective in terms of tumor regression in metastatic colon cancer patients pretreated with 5-fluorouracil.

Nocturnal plasma melatonin and alpha-melanocyte stimulating hormone levels during exacerbation of multiple sclerosis

The pineal gland has been implicated recently in the pathogenesis of multiple sclerosis (MS). To investigate this hypothesis further, we studied nocturnal plasma melatonin levels and the presence or absence of pineal calcification (PC) on CT scan in a cohort of 25 patients (5 men, 20 women; mean age: 41.1 years; SD = 11.1; range: 27-72) who were admitted to a hospital Neurology service for exacerbation of symptoms. Plasma alpha-melanocyte stimulating hormone (alpha-MSH) estimations were included in the study since there is evidence for a feedback inhibition between alpha-MSH and melatonin secretion. Abnormal melatonin levels were found in 13 patients (52.0%), 11 of whom had nocturnal levels which were below the daytime values (i.e., < 25 pg/ml). Although melatonin levels were unrelated to the patient's age and sex, there was a positive correlation with age of onset of symptoms (p < .0001) and an inverse correlation with the duration of illness (p < .05). PC was noted in 24 of 25 patients (96%) underscoring the pathogenetic relationship between MS and the pineal gland. Alpha-MSH levels were undetectable in 15 patients (60.0%), low in two patients (8.0%), normal in seven patients (28.0%), and elevated in one patient (4.0%). Collectively, abnormal alpha-MSH levels were found in over 70% of patients. These findings support the hypothesis that MS may be associated with pineal failure and suggest, furthermore, that alterations in the secretion of alpha-MSH also occur during exacerbation of symptoms. The relevance of these findings to the pathogenesis of MS are discussed.

Normalization of the light/dark rhythm of melatonin after prolonged subcutaneous administration of interleukin-2 in advanced small cell lung cancer patients

It has been demonstrated that antitumor immune response is an IL-2-dependent phenomenon. Moreover, experimental results suggest the existence of interactions between IL-2 and the pineal gland, which also plays a role in the control of immunity and cancer growth. Alterations of both IL-2 and melatonin secretion have been reported in cancer patients. To further investigate pineal/IL-2 relationships in humans with cancer, we evaluated the melatonin rhythm in seven advanced small cell lung cancer patients, before and at weekly intervals during immunotherapy with IL-2, given subcutaneously at a daily dose of 3 x 10(6) IU/m2 twice daily for 5 days/week for 4 weeks. Before IL-2, no patient showed a light/dark rhythm of melatonin. IL-2 administration induced a normalization of the melatonin circadian rhythm, with the appearance of a night time peak in 4/7 patients. This effect, however, disappeared with IL-2 interruption in 3/4 patients. This preliminary study, by showing that IL-2 may restore a normal melatonin rhythm, suggests that the anomalous pineal function in cancer may depend at least in part on the altered endogenous IL-2 production.