Biomodulation of cancer chemotherapy for metastatic colorectal cancer: a randomized study of weekly low-dose irinotecan alone versus irinotecan plus the oncostatic pineal hormone melatonin in metastatic colorectal cancer patients progressing on 5-fluorouracil-containing combinations.

Recent advances in immunobiological knowledge have suggested the possibility of enhancing the therapeutic activity of various chemotherapeutic agents by a concomitant administration of anti-oxidant drugs and/or immunomodulating neurohormones. In particular, the pineal neurohormone melatonin (MLT), which is able to exert both antioxidant and immunomodulating effects, has been proven to enhance the efficacy of various chemotherapeutic drugs, namely cisplatin, anthracyclines and 5-fluorouracil, whereas at present there are no data about its possible influence on cytotoxic drugs effective in the treatment of colon cancer other than 5-fluorouracil, such as irinotecan (CPT-11). The present study was performed to evaluate the influence of a concomitant administration of MLT on CPT-11 therapeutic activity in metastatic colorectal cancer. The study included 30 metastatic colorectal cancer patients progressing after at least one previous chemotherapeutic line containing 5-fluorouracil, who were randomized to be treated with CPT-11 alone or CPT-11 plus MLT. According to a weekly low-dose schedule, CPT-11 was given i.v. at 125 mg/m2/week for 9 consecutive weeks. MLT was administered orally at 20 mg/day during the dark period of the day. No complete response was observed. A partial response (PR) was achieved in 2 out of 16 patients treated with CPT-11 alone and in 5 out of 14 patients concomitantly treated with MLT. Moreover, a stable disease (SD) was obtained in 5 out of 16 patients treated with CPT-11 alone and in 7 out of 14 patients treated with CPT-11 plus MLT. Therefore, the percent of disease-control achieved in patients concomitantly treated with MLT was significantly higher than that observed in those treated with chemotherapy alone (12 out of 14 vs 7 out of 16, p < 0.05). The only important toxicity was diarrhoea grade 3-4, which occurred in 6 out of 16 patients treated with CPT-11 alone and in 4 out of 14 patients treated with CPT-11 plus MLT, which required a 50% dose reduction. However, taken together, patients treated with CPT-11 at 50% of the planned dose showed a percent of disease control comparable to that achieved in patients who had no dose reduction (6 out of 10 vs 13 out of 20). This preliminary study shows that the efficacy of weekly low-dose CPT-11 in pretreated metastatic colorectal cancer patients may be enhanced by a concomitant daily administration of the pineal hormone MLT, according to the results previously reported for other chemotherapeutic agents. Moreover, since the dose reduction of CPT-11 does not influence its efficacy, the dose of CPT-11 for successive studies might be not greater than 70 mg/m2.

Clinical and biological effects of interleukin-2 with or without a concomitant administration of granulocyte-macrophage colony-stimulating factor in metastatic cancer patients.

GM-CSF has been shown to modulate the anticancer activity of IL-2 with, however, controversial results depending on the great variety of biological effects induced by GM-CSF itself. The activation of dendritic cells and the generation of suppressive cells would constitute the main favourable and unfavourable biological effects of GM-CSF, respectively. The present study was performed in an attempt to evaluate the clinical and biological effects of a concomitant GM-CSF administration of the immunotherapy of metastatic renal cell carcinoma with IL-2. The study included 25 patients, who were randomized to be treated with IL-2 alone or IL-2 plus GM-CSF. IL-2 was injected subcutaneously at 6 MIU/day for 6 days/week for 4 consecutive weeks, coressponding to one complete cycle. GM-CSF was injected subcutaneously at 0.3 micrograms/kg b.w. for 3 consecutive days for the first 3 days of each week of IL-2 administration. Two immunotherapeutic cycles at 21-day intervals were planned. No significant difference was observed in the percent of non-progressive disease between the two groups of patients. The increase in leukocyte mean number was significantly higher in patients concomitantly treated with GM-CSF, whereas no difference was observed in that of lymphocytes. This preliminary study suggests that the concomitant administration of GM-CSF does not enhance the therapeutic efficacy of IL-2 immunotherapy of metastatic renal cell cancer.

Ten-year survival results in metastatic renal cell cancer patients treated with monoimmunotherapy with subcutaneous low-dose interleukin-2.

After more than ten years of clinical investigations, IL-2 immunotherapy appears to constitute the most effective treatment metastatic renal cell carcinoma (RCC),at least in terms of survival time. Moreover, it has been shown that comparable results may be achieved with different schedules of treatment, including intravenous high-dose or subcutaneous (SC) low-dose IL-2. Finally, it has been demonstrated that the association with interferon-alpha does not increase the efficacy of IL-2. Therefore, SC low-dose IL-2 alone may be considered as an adequate therapy for metastatic RCC. In fact, our previous studies with SC low-dose IL-2 alone have shown a 5-year survival time similar to that described with higher and more toxic doses of IL-2. This study was performed to analyze the 10-year survival results with SC low-dose IL-2 in metastatic RCC The study included 44 consecutive metastatic RCC patients, with a minimum follow-up of 120 months. One comlete immunotherapeutic cycle consisted of IL-2 at 3 million IU twice/day SC, 5 days/week for 6 consecutive weeks. In non-progressing patients, a second cycle was planned after a 21-day rest period. Complete response (CR) was achieved in only 2 out of 44 (4%) patients, while partial response (PR) was obtained in 8 out of /44 (18%) patients. Therefore, the response rate (CR + PR) was 10 out of 44 (22%), with a median response duration of 12 months. Stable disease (SD) occurred in 21 out of 44 (48%) patients,whereas the remaining 13 out of 44 (30%) patients had a progressive disease (PD). A 10-year survival was achieved in 2 out of 44 (5%) and the percent of survival at 10 years was significantly higher in patients with response or SD than in those with PD. This study confirms at 10 years the results previously referred to by other authors and by ourselves, in showing that the efficacy of IL-2 immunotherapy in terms of control of cancer growth is associated with a clear prolongation of the overall survival time in metastatic RCC.

A clinical study of taxotere versus taxotere plus the antiprolactinemic agent bromocriptine in metastatic breast cancer pretreated with anthracyclines.

Prolactin (PRL) constitutes a growth factor for breast cancer cell proliferation and abnormally elevated blood concentrations of PRL are associated with poor prognosis and reduced efficacy of antitumor therapies in metastatic breast carcinoma. It has already been demonstrated that low-dose bromocriptine, an antiprolactinemic long-acting dopaminergic drug, normalizes PRL blood concentrations in metastatic breast cancer patients with abnormally elevated PRL levels. In addition, previous clinical studies have already demonstrated a lower efficacy of chemotherapy with taxotere in metastatic breast cancer, with persistent hyperprolactinemia. We planned a controlled clinical study to evaluate the influence of a concomitant administration of the antiprolactinemic drug bromocriptine on the efficacy of chemotherapy with taxotere, in metastatic breast cancer patients progressing after chemotherapeutic combinations containing anthracyclines. The study included 30 randomized consecutive patients treated with taxotere alone or taxotere plus bromocriptine. Taxotere was given I.V. at 100 mg/m2 every 21 days for 3 cycles. Bromocriptine was given orally at 2.5 mg/day every day until the end of the chemotherapeutic treatment. Bromocriptine therapy induced a significant decline in PRL mean blood concentrations compared to patients treated by chemotherapy alone. No complete response was obtained. A partial response (PR) occurred in 5 out of 14 (36%) patients treated with taxotere plus bromocriptine and in only 2 out of 16 (13%) patients treated with taxotere alone. Moreover, a stable disease (SD) was obtained in 5 out of 16 patients treated with taxotere alone and in 7 out of 14 patients concomitantly treated with bromocriptine. Therefore, the percent of non-progressive disease (PR + SD) achieved in patients treated with taxotere plus bromocriptine was significantly higher with respect to that found in patients treated with taxotere alone (12 out of 14 vs 7 out of 16, p < 0.025). This preliminary clinical study would suggest that the inhibition of PRL secretion by antiprolactinemic drugs such as bromocriptine may enhance the efficacy of chemotherapy for metastatic breast cancer.

Abnormally enhanced blood concentrations of vascular endothelial growth factor (VEGF) in metastatic cancer patients and their relation to circulating dendritic cells, IL-12 and endothelin-1.

Elevated VEGF blood concentrations have been proven to be associated with poor prognosis in human neoplasms. This finding is generally explained as a consequence of the potential angiogenic properties of VEGF itself. However, preliminary experimental studies suggest that VEGF, in addition to its angiogenic activity, may also play an immunosuppressant role by inhibiting dendritic cell (DC) maturation. The present study was performed to analyze blood levels of VEGF in cancer patients in relation to those of another potentially angiogenic tumor growth factor, endothelin-1 (ET-1), and to the absolute number of circulating immature and mature DC, and serum levels of the best known antitumor cytokine, IL-12. The study was performed in 100 healthy controls and in 80 solid tumor patients (colorectal cancer: 24; gastric cancer: 17; cancer of pancreas: 4; lung cancer: 13; breast cancer: 11; renal cell cancer: 6; gynecologic tumors: 5), 48 of whom showed distant organ metastases. In each patient, we have evaluated serum concentrations of VEGF-165, total VEGF, ET-1, IL-12 and the circulating number of immature (CD123+) and mature (CD11c+) DC. Mean serum levels of VEGF-165 were significantly higher in metastatic patients than in controls or in non-metastatic patients, whereas the total amounts of VEGF were not significantly higher. Moreover, it has been observed that patients with abnormally elevated blood concentrations of VEGF-165 showed significantly lower mean values of immature DC, mature DC and IL-12 and significantly higher mean levels of ET-1 than those with normal concentrations. This study, by confirming that advanced neoplastic disease may be associated with increased endogenous secretion of VEGF, seems to suggest that the association between high blood levels of VEGF and poor prognosis in cancer does not depend only on VEGF-induced stimulation of the neovascularization, but also on VEGF-related immunosuppression.

Stimulation of IL-12 secretion by GM-CSF in advanced cancer patients.

In addition to its efficacy in the treatment of chemotherapy-induced neutropenia, recent evidence would suggest that GM-CSF may have immunomodulatory effects on anticancer immunity. In particular, GM-CSF has been proven to promote dendritic cell maturation, with following potential stimulation of the anticancer cytokine, IL-12. Unfortunately, at present there are only few and controversial results on GM-CSF effects on IL-12 secretion in cancer patients. This preliminary study was performed to evaluate IL-12 response to an acute injection of GM-CSF in human neoplasms. The study included 20 advanced cancer patients, who received GM-CSF for chemotherapy-induced neutropenia. GM-CSF was injected at 3 micrograms/kg at 8.00 A.M., and venous blood samples were drawn before GM-CSF, and at 4, 8, 12 and 24 hours after its injection. Serum levels of IL-12 were measured by an enzyme immunoassay. High basal levels of IL-12 were seen in 8/20 patients. In patients with abnormally high pretreatment levels of IL-12, no significant change occurred in IL-12 mean serum concentration after GM-CSF administration. In contrast, patients with normal baseline levels of IL-12 showed a significant increase in IL-12 mean concentrations in response to GM-CSF, with a peak after 12 hours. This preliminary study seems to show that GM-CSF may acutely stimulate IL-12 secretion in cancer patients. Further studies are required to evaluate the effects of chronic GM-CSF administration, and the impact of GM-CSF-induced secretion of IL-12 on the efficacy of the immunotherapies of cancer with cytokines, such as IL-2. In any case, this study would justify further research in the emerging oncological applications of GM-CSF as an immunomodulatory agent on host anticancer defenses.

Anti-angiogenic activity of melatonin in advanced cancer patients.

OBJECTIVES: The anticancer activity of the indole melatonin has been explained to be due to its immunomodulatory, anti-prolferative and anti-oxidant effects, whereas at present no data are available about its possible influence on the angiogenesis, which has been shown to be one of the main biological mechanisms responsible for tumor dissemination. Vascular endothelial growth factor (VEGF) is the most active angiogenic factor, and the evidence of abnormally high blood levels or VEGF has been proven to be associated with poor prognosis in cancer patients. To investigate the influence of melatonin on angiogenesis, in this preliminary study we have evaluated the effects of melatonin therapy on VEGF blood levels in advanced cancer patients. MATERIAL & METHODS: The study included 20 metastatic patients, who progressed on previous conventional antitumor therapies and for whom no other effective treatment was available. Melatonin was given orally at 20 mg/day in the evening for at least 2 months. Serum levels of VEGF were measured by an enzyme immunoassay on venous blood samples collected at 15-day intervals. RESULTS: The clinical response consisted of minor response (MR) in 2, stable disease (SD) in 6 and progressive disease (PD) in the remaining 12 patients. VEGF mean levels decreased on therapy, without, however, statistical differences with respect to the pre-treatment values. In contrast, by evaluating changes in VEGF levels in relation to the clinical response, non-progressing patients (MR + SD) showed a significant decline in VEGF mean concentrations, whereas no effect was achieved in progressing patients. CONCLUSIONS: This study, by showing that melatonin-induced control or the neoplastic growth is associated with a decline in VEGF secretion, would suggest that the pineal hormone may control tumor growth at least in part by acting as a natural anti-angiogenic molecule, with a following opposition or angiogenesis-dependent cancer proliferation.

Thrombopoietic properties of 5-methoxytryptamine plus melatonin versus melatonin alone in the treatment of cancer-related thrombocytopenia.

Recent studies have shown that the hematopoietic system is under neuroendocrine control. In particular, thrombopoiesis has been proven to be stimulated by melatonin, and the pineal indole has been shown to be effective in the treatment of thrombocytopenia resulting from different causes. At present, however, there are no data concerning the possible thrombopoietic activity of pineal indoles other than melatonin. The present study was carried out to evaluate the effect of a concomitant administration of the pineal indole 5-methoxytryptamine in patients with cancer-related thrombocytopenia who did not respond to melatonin alone. The present study included 30 patients, who were randomized to receive melatonin alone (20 mg/day orally in the evening) or melatonin plus 5-methoxytryptamine (1 mg/day orally in the early afternoon). A normalization of platelet count was achieved in 5/14 (36%) patients treated with melatonin plus 5-methoxytryptamine and in none of the patients treated with melatonin alone (P < 0.05). Moreover, mean platelet number significantly increased only in the patients treated with melatonin plus 5-methoxytryptamine. This preliminary clinical study would suggest that 5-methoxytryptamine, a pineal indole, may also exert thrombopoietic activity. Further studies, however, will be required to establish whether 5-methoxytryptamine may play a direct thrombopoietic activity, or whether it may act by improving melatonin's efficacy.

Changes in circulating dendritic cells and IL-12 in relation to the angiogenic factor VEGF during IL-2 immunotherapy of metastatic renal cell cancer.

Angiogenesis and immunosuppression are the main biological mechanisms responsible for cancer progression. Moreover, recent observations suggesting a negative influence of angiogenesis on anticancer immunity have shown that some angiogenic factors, such as VEGF, may induce immunosuppression. In addition, the evidence of abnormally high blood levels of VEGF has been proven to be associated with resistance to IL-2 immunotherapy. The present study was performed to establish a possible relation ship between the efficacy of IL-2 cancer immunotherapy and changes in circulating levels of VEGF, IL-12, mature and immature dendritic cells (DC). The study included 25 metastatic renal cell cancer patients who underwent subcutaneous low-dose IL-2 immunotherapy (6 MIU/day for 6 days/week for 4 weeks). Immature and mature DCs were identified as CD123+ and CD11c+ cells, respectively. The clinical response consisted of partial response (PR) in five, stable disease (SD) in 11 and progressive disease (PD) in the remaining nine patients. The mean IL-12 levels observed during IL-2 immunotherapy were significantly higher in patients with PR or SD than in those with PD, whereas the mean VEGF concentrations were significantly higher in patients who had PD than in those with PR or SD. Finally, a significant increase in the mean number of circulating mature DCs occurred only in patients with PR or SD, whereas no significant change was seen in patients with PD. By contrast, no significant change was observed in the mean number of immature DCs. This study shows that the efficacy of IL-2 immunotherapy is associated with a significant increase in circulating mature DCs and IL-12, without any concomitant increase in VEGF concentrations. Further studies will be required to better define the relationship between activation of anticancer immunity and control of angiogenesis-related mechanisms.

Circulating immature and mature dendritic cells in relation to lymphocyte subsets in patients with gastrointestinal tract cancer.

Cancer-related deficiency in circulating dendritic cells (DC), whose important anticancer role is well established, has been proven to be associated with lymphocytopenia. This study was performed to evaluate which lymphocyte subset is most markedly related to the failure of the DC system. The study included 30 patients with gastrointestinal tract cancer, 10 of whom had distant organ metastases. Immature and mature DCs were measured by FACS and monoclonal antibodies against CD123 and CD11c antigens, respectively. Low levels of immature and mature DCs were observed in 63% and 43% of patients, respectively. Patients with low levels of circulating mature DCs had significantly lower values of T lymphocytes, T helper lymphocytes and NK cells than those with normal mature DC levels. In contrast, no significant difference was seen between patients with normal or abnormally low values of immature DCs. Conversely, patients with a decreased number of T lymphocytes, T helper lymphocytes and NK cells showed significantly lower values of circulating mature DCs than those with lymphocyte subsets within the normal range, whereas no difference was seen in immature DC amounts. This study suggests that only mature DC deficiency may be associated with important lymphocyte subset alterations in cancer patients, whereas deficiency in immature DCs does not seem to be related to other immune cell disorders.

Serum concentrations of interleukin-18 in early and advanced cancer patients: enhanced secretion in metastatic disease.

The recent availability of adequate methods for cytokine measurement could contribute to better understanding the immunophysiopathology of neoplastic disease. Unfortunately, very little data is available about cytokine secretion in cancer patients. At present, IL-2, IL-12 and IL-15 represent the major antitumor cytokines in humans. Preliminary clinical studies have shown a progressive decline in IL-2 levels with cancer progression, whereas IL-12 seems to increase in the advanced disease. IL-18 is the latest cytokine discovered by potential anticancer and anti-angiogenetic activity, and it has effects similar to those of IL-12. This preliminary study was carried out to analyze IL-18 secretion in early or advanced cancer patients. The study included 40 cancer patients (lung cancer, 21; gastrointestinal tumors, 19), 17 of whom had metastatic disease, and 50 healthy controls. Serum levels of IL-18 were measured by ELISA. No significant difference in IL-18 mean levels was seen between controls and non-metastatic patients. In contrast, metastatic patients showed significantly higher IL-18 mean values with respect to both healthy controls and non-metastatic patients. This preliminary study seems to suggest that metastatic disease may be characterized by enhanced IL-18 secretion the biological and prognostic significance to be established by successive clinical investigation.