title: Prostaglandin D(2), its metabolite 15-d-PGJ(2), and peroxisome proliferator activated receptor-gamma agonists induce apoptosis in transformed, but not normal, human T lineage cells.
abstract: Prostaglandin D(2) (PGD(2)) is abundantly produced by mast cells, platelets, and alveolar macrophages and has been proposed as a key immunoregulatory lipid mediator. 15-Deoxy-Delta(12,14)-PGJ(2) (15-d-PGJ(2)), a key PGD(2) metabolite, is under intense study as a potential anti-inflammatory mediator. Little is known about PGD(2) or the role of 15-d-PGJ(2), if any, in regulating the activities of human T lineage cells. In this report we demonstrate that both PGD(2) and 15-d-PGJ(2) have potent antiproliferative effects, and in fact kill human T lymphocyte lines derived from malignant cells by an apoptotic mechanism. Interestingly, normal human T cells were not similarly affected. Although the T lymphocyte lines express mRNA for the PGD(2) receptor (DP-R), a potent DP receptor agonist, BW245C, did not inhibit the proliferation or viability of the cells, suggesting an alternative mechanism of action. PGD(2) and 15-d-PGJ(2) can bind to the peroxisome proliferator activated receptor-gamma (PPAR-gamma) which is implicated in lipid metabolism and apoptosis. Exposure to synthetic PPAR-gamma ligands (e.g. ciglitazone, troglitazone) mimicked the inhibitory responses of PGD(2) and 15-d-PGJ(2), and induced apoptosis in the transformed T cells consistent with a PPAR-gamma-dependent mechanism. These observations suggest that PPAR-gamma ligands (which may include PGD2) provide strong apoptotic signals to transformed, but not normal T lymphocytes. Thus, the efficacy of utilizing PPAR-gamma and its ligands as therapeutics for human T cell cancers needs to be further evaluated.
authors.affiliation: Department of Microbiology and Immunology and the James P. Wilmot Cancer Center, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA.
authors.forename: Sarah G
authors.initials: SG
authors.lastname: Harris
authors.forename: Richard P
authors.initials: RP
authors.lastname: Phipps
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000502:physiology*; D002455:Cell Division / Q000187:drug effects; D002461:Cell Line, Transformed; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured / Q000473:pathology / Q000502:physiology; D002839:Chromans / Q000494:pharmacology; D006801:Humans; D006827:Hydantoins / Q000494:pharmacology; D020287:In Situ Nick-End Labeling; D015230:Prostaglandin D2 / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000502:physiology*; D018160:Receptors, Cytoplasmic and Nuclear / Q000819:agonists*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000473:pathology / Q000502:physiology; D013844:Thiazoles / Q000494:pharmacology; D045162:Thiazolidinediones; D014157:Transcription Factors / Q000819:agonists*; D000077288:Troglitazone
chemical_list: C097240:15-deoxy-delta(12,14)-prostaglandin J2; D000970:Antineoplastic Agents; D002839:Chromans; D006827:Hydantoins; D018160:Receptors, Cytoplasmic and Nuclear; D013844:Thiazoles; D045162:Thiazolidinediones; D014157:Transcription Factors; C087760:3-((2-cyclohexyl-2-hydroxyethylidene)amino)-2,5-dioxo-4-imidazolidineheptanoic acid; D000077288:Troglitazone; D015230:Prostaglandin D2