stilbenes and Leukemia--T-Cell

Topics: Apoptosis; Caspases; Cell Cycle Checkpoints; Cell Proliferation; Humans; Indazoles; Jurkat Cells; Leukemia, T-Cell; MAP Kinase Signaling System; Membrane Potential, Mitochondrial; Phosphorylation; Piperazines; Reactive Oxygen Species; Stilbenes

Resveratrol, a natural polyphenol, possesses many beneficial health properties but its therapeutic application is limited due to its low water solubility and instability against oxidative processes. To improve the stability and lipophilicity of the natural compound, we synthesized a resveratrol prodrug, termed FEHH4-1. In the present study, we compared the antiproliferative and pro-apoptotic effects of resveratrol with FEHH4-1 on Jurkat T-cells.. Cell proliferation and viability were monitored by 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide assay, annexin-V/7-amino-actinomycin D staining and western blot. To induce interleukin-2 (IL2) expression, cells were stimulated with phorbol 12-myristate 13-acetate/phytohemagglutinin. IL2 production was quantified by enzyme-linked immunosorbent assay. IL2 promoter activity was studied by a Jurkat T-cell line containing an IL2 promoter luciferase reporter construct.. Both polyphenols inhibited proliferation, induced apoptotic cell death and blocked IL2 synthesis in Jurkat T-cells. Most importantly, FEHH4-1 was three-to four-times more potent than resveratrol.. FEHH4-1 had improved antiproliferative and pro-apoptotic potential against Jurkat T-cells compared to resveratrol.

Topics: Antineoplastic Agents; Apoptosis; Apoptosis Regulatory Proteins; CD4-Positive T-Lymphocytes; Cell Proliferation; Cell Survival; Dose-Response Relationship, Drug; Gene Expression Regulation, Leukemic; Humans; Interleukin-2; Jurkat Cells; Leukemia, T-Cell; Prodrugs; Promoter Regions, Genetic; Resveratrol; Stilbenes; Transfection

Resveratrol is a natural occurring phytoalexin present in grapes and berries, that has been shown to have chemopreventive/therapeutic activity. But the precise mechanism of resveratrol involved in leukemia is not well understood. In this study, we examine its anti-leukemia effect both in vitro and in vivo. Our data indicate that resveratrol contributes to inhibiting growth, inducing apoptosis and cell cycle arrest in the three leukemia cell lines (Jurkat, SUP-B15, and Kasumi-1), and reducing the phosphorylation of STAT3, meanwhile modulating the expression of Bcl-2 and Bax. In vivo, resveratrol could prolong the life span of Kasumi-1-bearing mice, and attenuate the activity of STAT3. Taken altogether, this investigation focuses on signaling pathways involved in STAT3 by resveratrol and to delineate its molecular mechanisms underlying anti-leukemia effect.

Topics: Animals; Antineoplastic Agents; Apoptosis; bcl-2-Associated X Protein; Cell Cycle; Cell Proliferation; Gene Expression Regulation, Leukemic; Humans; Jurkat Cells; Leukemia, T-Cell; Male; Mice; Mice, Inbred BALB C; Neoplasm Transplantation; Proto-Oncogene Proteins c-bcl-2; Resveratrol; Signal Transduction; STAT3 Transcription Factor; Stilbenes

We have found that resveratrol (trans-3,4',5-trihydroxystilbene) induced apoptosis in multiple myeloma (MM) and T-cell leukemia cells through coclustering of Fas/CD95 death receptor and lipid rafts, whereas normal lymphocytes were spared. Tumor necrosis factor-related apoptosis-inducing ligand receptors, Fas-associated death domain-containing protein (FADD), procaspase-8, procaspase-10, c-Jun amino-terminal kinase and Bid were also recruited into lipid rafts on resveratrol incubation with MM and T-cell leukemia cells. Raft disruption inhibited resveratrol-induced apoptosis. Bcl-XL overexpression prevented resveratrol-induced disruption of mitochondrial transmembrane potential (DeltaPsi(m)) and apoptosis. A FADD dominant-negative mutant, that blocked Fas/CD95 downstream signaling, precluded resveratrol-induced DeltaPsi(m) loss and apoptosis, indicating a sequence of Fas/CD95 signaling-->mitochondrion in the apoptotic response triggered by resveratrol. Cells deficient in Fas/CD95 did not undergo resveratrol-induced apoptosis. Pretreatment of MM cells with interferon-gamma upregulated Fas/CD95 and caspase-8, and potentiated resveratrol-induced apoptosis. Our data indicate that recruitment of Fas/CD95 death receptor and downstream signaling molecules into lipid rafts, followed by DeltaPsi(m) disruption, underlies the apoptotic action of resveratrol in MM and T-cell leukemic cells. Combination of resveratrol with perifosine or bortezomib potentiated the apoptotic response induced by each single drug. These results also highlight the role of recruitment of Fas/CD95 signaling in lipid rafts in antimyeloma and antileukemia chemotherapy.

Topics: Antineoplastic Agents; Apoptosis; bcl-X Protein; BH3 Interacting Domain Death Agonist Protein; Boronic Acids; Bortezomib; Caspase 10; Caspase 8; Cell Line, Tumor; Drug Synergism; fas Receptor; Fas-Associated Death Domain Protein; Flow Cytometry; Fluorescent Antibody Technique; Humans; JNK Mitogen-Activated Protein Kinases; Jurkat Cells; Leukemia, T-Cell; Membrane Microdomains; Microscopy, Confocal; Mitochondria; Multiple Myeloma; Phosphorylcholine; Pyrazines; Resveratrol; Signal Transduction; Stilbenes

Inhibition of proliferation by resveratrol of CEM-C7H2 lymphocytic leukemia cells was paradoxically associated with an enhanced cellular 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT)-reducing activity. This phenomenon was most pronounced at the sub-apoptotic concentration range of 5-20 microM resveratrol. The results of our study show that the MTT-reducing activity can be increased by the polyphenolic antioxidant resveratrol without a corresponding increase in the number of living cells and that this occurs at a concentration range of the antioxidant which is not sufficient to induce apoptosis but suffices to slow down cell growth. This phenomenon appears to be restricted to proliferation inhibitors with antioxidant properties and is cell type-specific. Thus, in determining the effects of flavonoids and polyphenols on proliferation, in certain cell types this might represent a pitfall in the MTT proliferation assay.

Topics: Antioxidants; Apoptosis; Artifacts; Cell Division; Colorimetry; Dose-Response Relationship, Drug; Electron Transport; Formazans; Growth Inhibitors; Histocytochemistry; Humans; Indicators and Reagents; Leukemia, T-Cell; Mitochondria; NAD; NADP; Organ Specificity; Oxidation-Reduction; Resveratrol; Stilbenes; Subcellular Fractions; T-Lymphocytes; Tetrazolium Salts; Thiazoles; Tumor Cells, Cultured