Neuroimmunotherapy of untreatable metastatic solid tumors with subcutaneous low-dose interleukin-2, melatonin and naltrexone: modulation of interleukin-2-induced antitumor immunity by blocking the opioid system.

OBJECTIVES: The preliminary applications of the psychoneuroimmunological knowledges to the treatment of human diseases have confirmed the possibility to amplify IL-2-dependent anticancer immunity by the pineal hormone melatonin (MLT) or by opioid antagonist, such as naltrexone (NTX), which act by activating TH1 lymphocytes or suppressing TH2 lymphocytes, respectively. At present, however, there are no data about the immunobiological effects of a concomitant administration of both MLT and NTX on IL-2-induced anticancer immunity. This preliminary study was carried out to evaluate whether the association of NTX may further enhance the lymphocytosis induced by the neuroimmunotherapy with IL-2 plus MLT. MATERIALS & METHODS: The study included 14 consecutive untreatable metastatic solid tumor patients. According to a cross-over randomized study, the patients were treated during two consecutive immunotherapeutic cycles at 21-day intervals with IL-2 plus MLT alone or with IL-2 plus MLT plus NTX. IL-2 was injected subcutaneously at 3 MIU/day for 6 days/week for 4 weeks, MLT was given orally at 20 mg /day in the evening every day, and NTX was given orally at 100 mg in the morning every next day. For the immune evaluation, venous blood samples were drawn before the onset of treatment and at weekly intervals. RESULTS: Lymphocyte mean number significantly increased after both IL-2 plus MLT and IL-2 plus MLT plus NTX. However, the concomitant administration of NTX induced a significantly higher increase in lymphocyte mean number with respect to that achieved with IL-2 plus MLT alone. In contrast, the increase in eosinophil mean number was significantly higher on IL-2 plus MLT alone. CONCLUSIONS: This preliminary study shows that the association of NTX further amplifies the lymphocytosis obtained by IL-2 plus MLT. Since the lymphocytosis represents the most important favourable prognostic variable predicting the anticancer efficacy of IL-2 immunotherapy, it is probable that a cancer neuroimmunotherapy with IL-2 plus both MLT and NTX to activate TH1 and suppress TH2 cells respectively, may deserve more promising results in the treatment of human neoplasms according to the psychoneuroimnunological knowledge.

A new neuroimmunotherapeutic strategy of subcutaneous low-dose interleukin-2 plus the long-acting opioid antagonist naltrexone in metastatic cancer patients progressing on interleukin-2 alone.

OBJECTIVES: Recent advances in knowledge of Psychoneuroimmunology have shown that several neuroactive substances, including neurohormones and neuropeptides, may exert immunomodulatory effects. However, despite the great variety of potential neuroimmune interactions, at present we may recognize two major neuroendocrine systems exerting a physiological neuroimmunomodulatory function, consisting of the pineal gland and the brain opioid system, provided by immunostimulatory and immunosuppressive effects, respectively. Recent in human studies have demonstrated the possibility to amplify the biological activity of IL-2, the major anticancer cytokine, by pineal indoles. MATERIALS & METHODS: The present study was carried out to draw some preliminary in human results on the possible immunomodulatory effects of the inhibition of the brain opioid activity by a long-acting opioid antagonist, naltrexone (NTX). The study was performed in 10 metastatic renal cell cancer patients, who had progressed on a previous immunotherapeutic cycle with IL-2 alone. Patients were treated with the same doses of IL-2 (6 million lU/day subcutaneously for 6 days/week for 4 weeks) plus an oral administration of NTX at a dose of 100 mg every 2 days. RESULTS: The clinical response consisted of a partial response in 1 and a stable disease in 5 patients, whereas the other 4 patients progressed. Therefore, the percent of non-progressive disease was 6/10 (60%). Moreover, mean lymphocyte increase achieved during IL-2 plus NTX was significantly higher (P<0.05) than that obtained during the previous treatment with IL-2 alone. CONCLUSIONS: This study shows that a blockade of the brain opioid system, which plays a physiological immunosuppressive role, may improve the anticancer effects of IL-2 in humans.

Evidence for a neuroimmunomodulatory and a hematopoietic role of the Luschka's coccygeal body(3).

OBJECTIVES: In humans the glomus coccygeus was described in 1860 by Luschka. It is present at the coccyx tip and corresponds to a complex anastomosis between the median sacral artery and vein, and it is innervated by sympathetic fibers. In rats and mice it has been located in the tail ventral face. Its function is not known. According to our previous work, which demonstrated that hematopoiesis is under a noradrenergic control and based on the presence of epithelioid cells and sympathetic innervation, we assumed that the coccygeal gland might influence hematopoiesis via neuroendocrine or neural mechanisms. Therefore, the present study was undertaken to analyze the effect of glomus coccygeus on hematopoiesis. MATERIAL AND METHODS: Peripheral blood leukocyte and platelet concentrations as well as body temperature (BT) and body weight (BW), and norepinephrine (NE), adrenaline (A) and dopamine (DA) content in bone marrow of Luschkaectomized (LCGx), Sham LCGx operated (ShLCGx) and normal mice (Co) were investigated. RESULTS: We found that in LCGx vs. ShLCGx and Co, platelets and neutrophils increased while lymphocytes decreased. The effect of LCGx was significant from day 0 until day 65. Total leukocytes, monocytes, granulocytes, eosinophils and BT did not show any variation. Moreover, 22 days after the operation the amount of NE, A and DA seemed to be decreased in LCGx vs. ShLCGx while the difference was less evident between ShLCGx vs. Co. CONCLUSIONS: This study suggests for the first time a possible hematopoietic function and an immunomodulatory activity of the "Luschka's body" or Coccygeal body by a modulation of the sympathetic nervous system.

Oncostatic activity of pineal neuroendocrine treatment with the pineal indoles melatonin and 5-methoxytryptamine in untreatable metastatic cancer patients progressing on melatonin alone.

OBJECTIVE: The recent advances in psycho-neuro-endocrino-immunology have demonstrated the existence of several endogenous neuroendocrine substances, capable of affecting both tumor growth and host anticancer immune defenses. The pineal gland would represent one of the most important organs releasing antiproliferative and immunostimulating substances, the most known of them is melatonin (MLT). However, MLT would not be the only pineal indole provided by antitumor activity. Other pineal indoles, namely 5-methoxytryptamine (5-MTT), would play antitumor effects, by either inhibiting cancer cell proliferation or stimulating the anticancer immunity. Preliminary data have shown that MLT may deserve antitumor activity in the treatment of human neoplasms, whereas at present there are no clear data about 5-MTT. In an attempt to obtain some preliminary data about the anticancer properties of 5-MTT in humans, we have evaluated the efficacy of MLT plus 5-MTT in untreatable advanced cancer patients progressing on MLT alone. METHODS: The study included 73 untreatable advanced solid tumor patients, who had progressed after two months of MLT therapy alone. According to tumor histotype, patients were randomized to receive MLT alone (20 mg/day orally in the evening) or MLT plus 5-MTT (1 mg at noon orally), every day for at least two months. The clinical response was evaluated according to WHO criteria. RESULTS: A partial response (PR) occurred in two patients treated with MLT + 5-MTT and in none of the patients receiving MLT alone. A stable disease (SD) was achieved in only 2/37 patients on MLT therapy alone, and in 8/36 patients receiving MLT plus 5-MTT. Therefore, the percent of non-progressing patients (SD + PR) obtained with MLT plus 5-MTT was significantly higher than that obtained with MLT alone. Moreover, the relief of asthenia and depressant symptoms was significantly higher in patients concomitantly treated with 5-MTT. DISCUSSION: This preliminary study would suggest that the concomitant administration of the less known pineal indole 5-MTT, also provided by antiproliferative and immunomodulating effects, may further amplify the oncostatic activity of the pineal hormone MLT in the palliative and curative therapy of advanced untreatable human solid neoplasms.

The pineal neurohormone melatonin and its physiologic opiatergic immunoregulatory role

The pineal gland functions as a neuroendocrine transducer that coordinate the organism response to changing environmental stimuli such as light and temperature. The main and best known pineal neurohormone is melatonin that is synthesized and released in a circadian fashion with a peak during the night darkness hours. We have recently reported that melatonin exerts important immuno regulatory functions. Here we describe the astonishing property of exogenous melatonin which is able to counteract completely the depressive effect of anxiety-restraint stress and/or of corticosterone on thymus weight, andibody production and antiviral responses. This effect seems to be mediated by antigen-activated T cells via an opiatergic mechanism.