Targeting the prostaglandin (PG) pathway is potentially a critical intervention for the prevention and treatment of cancer. Central to PG biosynthesis are two isoforms of cyclooxygenase (COX 1 and 2), which produce prostaglandin H(2) (PGH(2)) from plasma membrane stores of fatty acids. COX-1 is constitutively expressed, whereas COX-2 is an inducible isoform upregulated in many cancers. Differen...

Human urine was analyzed by mass spectrometry for the presence of prostaglandins. Prostaglandin E2 and F2alpha were detected in urine from females by selected ion monitoring of the prostaglandin E2-methylester-methoxime bis-acetate and the prostaglandin F2alpha-methyl ester-Tris-trimethylsilylether derivative. Additional evidence for the presence of prostaglandin F2alpha was obtained by isolati...

Prostaglandin E, and a CAMP phosphodiesterase inhibitor 4-(3-butoxy-4-methoxybenzyl)-2imidazolidinone, R020-1724, were used to induce differentiation in mouse neuroblastoma cells in culture. The incorporation of amino acids and phosphate into nuclear proteins of control and drug-treated cells (1 h and 3 days after treatment) was examined using double radioisotopic techniques. A marked decrease ...

The effect of bradykinin on prostaglandin E 2 formation in cells from human trabecular bone has been studied. The cells responded to parathyroid hormone with enhanced cyclic AMP formation and were growing as cuboidal-shaped, osteoblast-like cells. In these isolated human osteoblast-like cells, bradykinin (1 #tool/l) caused a rapid (5 min) stimulation of prostaglandin E2 formation. This finding ...

Human microsomal prostaglandin E synthase-1 (mPGES-1) is a membrane associated protein that catalyzes the conversion of prostaglandin H(2) (PGH(2)) into prostaglandin E(2) (PGE(2)). In this study, the expression of human mPGES-1 in E. coli was significantly enhanced by modifying the utility of specific codons and the recombinant mPGES-1 was efficiently purified to homogeneity. The K(m) and V(ma...

Kinetic behavior most consistent with the presence of two independent, but simultaneously acting, regulatory effector sites for prostaglandins has been presented for adenylate cyclase (EC 4.6.1.1) of rabbit intestinal epithelial cells. One site regulates activation of the catalytic site, while the other site regulates inhibition. A synthetic prostaglandin analogue, 7-oxa-13-prostynoic acid, is ...

Prostaglandin and monocyte modulation of a T-lymphocyte cell capable of undergoing clonal expansion was studied. Circulating human mononuclear cells were isolated by density centrifugation. After 24 h in culture with phytohemagglutinin present, the cells were mixed with 0.3% agar and overlayed onto a 0.5% agar layer that contained media and phytohemagglutinin. At day 6, colonies that contained ...

Prostaglandins of the E and F series in rabbit plasma were estimated by radioimmunoassay after chromatographic separation during fever following the intravenous injection of Newcastle disease virus, E. co/t'-endotoxin, or endogenous pyrogen. Although concentrations of prostaglandins from both series are increased considerably by the three pyrogens, there seemed to be no cor­ relation between pr...

To examine the temporal effects of plasmin generated in vivo on platelet function, we infused tissue-type plasminogen activator (t-PA) in rabbits over 3 hours and measured ex vivo platelet aggregation. We noted an initial increase in the aggregation response to ADP occurring 30 minutes after the start of infusion. This enhanced response was short-lived and by 180 minutes was reduced, compared w...

We have studied functional alteration of immunocytes in mice following inoculation of Toxocara canis second stage larvae. Results indicated depression of lymphocyte blastogenesis in response to concanavalin-A, phytohemagglutinin and allogeneic non B-cells; however, B-cell polyclonal activation was not affected as indicated by the production of total IgG. In contrast, frequency of antibody ...