Plasma cytokine concentration changes induced by the antitumor agents dipterinyl calcium pentahydrate (DCP) and related calcium pterins

Analysis of plasma cytokine concentration changes determined that oral dosing with the antitumor agent (1:4 mol:mol) calcium pterin (CaPterin) increased plasma IL-10, decreased plasma IL-6, and decreased plasma IFN-γ concentrations in nude mice with MDA-MB-231 xenograph tumors [Moheno, P., Pfleiderer, W., Dipasquale, A.G., Rheingold, A.L., Fuchs, D., 2008. Cytokine and IDO metabolite changes effected by calcium pterin during inhibition of MDA-MB-231 xenograph tumors in nude mice. Int. J. Pharm. 355, 238–248]. A further analysis, reported here, of plasma cytokine concentration changes in nude mice with the same tumor xenographs treated with dipterinyl calcium pentahydrate (DCP), (1:2 mol:mol) calcium pterin, and CaCl2·2H2O has been carried out. The measured cytokines included: IL-1β, IL-2, IL-4, IL-6, IL-10, IL-12, IFN-γ, and TNF-α. The major preliminary findings from the analyses of these data are that (1) the overall relative tumor volumes for the treatments correlated significantly with a full study antitumor plasma cytokine pattern (fsAPCP), a composite measure consisting of decreased plasma IL-6 and increased IL-4 concentrations, and (2) DCP induces a significant threshold antitumor response strongly correlated to a derived DCP antitumor plasma cytokine pattern (DCP/APCP) consisting of plasma IL-12, IL-6, and IL-4 concentration changes. This DCP/APCP composite measure identifies plasma IL-12 concentration increases, plasma IL-6 concentration decreases, and plasma IL-4 concentration increases correlated to relative tumor volume decreases caused by DCP dosing. The finding that the novel calcium pterins and CaCl2·2H2O treatments decrease plasma IL-6 concentrations corroborates the previous finding that CaPterin dosing decreases plasma IL-6 concentrations in this mouse/tumor system [Moheno, P., Pfleiderer, W., Dipasquale, A.G., Rheingold, A.L., Fuchs, D., 2008. Cytokine and IDO metabolite changes effected by calcium pterin during inhibition of MDA-MB-231 xenograph tumors in nude mice. Int. J. Pharm. 355, 238–248].