Search

In the present study we evaluated the ability of either medroxyprogesterone acetate (MPA) or megestrol acetate (MA) to reduce cisplatin (CDDP)-induced serotonin (5-HT) release from peripheral blood mononuclear cells (PBMC) of cancer patients. Sixteen patients with cancer of different sites, all in advanced stage of disease, were studied (10 for MPA and 6 for MA). The levels of 5-HT in culture supernatants of PBMC stimulated with CDDP were higher than controls (100 nM vs 51 for MPA study and 123 vs 64 for MA study) and were in the same range of PHA-stimulated PBMC. The addition into cultures of MPA or MA was able to significantly reduce the CDDP-induced production of 5-HT (62 nM for MPA, and 46 for MA study). MPA as well as MA are able to inhibit 5-HT production and/or release by CDDP-stimulated PBMC of cancer patients: this finding to our knowledge has not been previously reported. The concentrations of MPA and MA used in cultures were in the same range as those raised in plasma following the clinical administration of daily doses of 1,000/2,000 mg of MPA and 320 to 960 mg of MA.

Medroxyprogesterone acetate (MPA) is widely used in oncology both in the treatment of hormone-related cancers and as supportive therapy in anorexia/cachexia syndrome (ACS), but conclusive data are not yet available to explain its anticachectic effect. ACS is characterised by weight loss, changes in metabolism, reduction of appetite, nausea and vomiting. Several cytokines, mainly interleukin (IL)-1, IL-2, IL-6 and tumour necrosis factor alpha (TNF alpha), are involved in the pathogenesis of ACS. Additionally, nausea and vomiting can be mediated by factors inducing serotonin (5-HT) production and/or release by pleiotropic cells including activated T lymphocytes. In the present study, we report the effect of MPA on peripheral blood mononuclear cells (PBMC) from 10 cancer patients in advanced stage of disease (6 head and neck, 2 colon, 1 lung and 1 ovary). The proliferative response of PBMC to PHA, anti-CD3 monoclonal antibody (MAb) or recombinant IL-2 (rIL-2), the production of IL-1 beta, IL-2, IL-6, TNF alpha and 5-HT by PHA-stimulated PBMC and the expression of lymphocyte membrane-bound IL-2 receptor (IL-2R) subunities (CD25 and CD122) were studied. The addition of MPA significantly reduced the PBMC proliferative response to PHA and anti-CD3 MAb but not to rIL-2. MPA 0.2 microgram/ml was also capable of reducing the levels of IL-1 beta, IL-6, TNF alpha and 5-HT produced in culture by PHA-stimulated PBMC, whereas it did not induce any change in the percentage of PBMC expressing either CD25 or CD122 or both molecules after stimulation with PHA or anti-CD3 mAb.

Corticosteroids counteract cisplatin (CDDP)-induced acute emesis but the mechanism involved is still unknown. Therefore, the aim of this study was to verify whether CDDP can induce serotonin (5HT) release from peripheral blood mononuclear cells (PBMC) and determine whether methylprednisolone (MP) can inhibit such release. Blood from 10 healthy volunteers was used. Our study showed that CDDP did induce 5HT release from PBMC dose-dependently (10 +/- 1 nM for controls, 18 +/- 4 nM for CDDP 0.01 microgram and 30 +/- 4 nM for CDDP 0.1 microgram, P < 0.001) and that the addition of MP to cultures of PBMC in the presence of CDDP induced a significant decrease of 5HT concentrations. Our results highlight a new mechanism through which CDDP could induce emesis and suggest a further mechanism by which corticosteroids mediate their anti-emetic effect.