title: Resveratrol (trans-3,5,4'-trihydroxystilbene) suppresses EL4 tumor growth by induction of apoptosis involving reciprocal regulation of SIRT1 and NF-κB.
abstract: METHODS
  Understanding the molecular mechanisms through which natural products and dietary supplements exhibit anticancer properties is crucial and can lead to drug discovery and chemoprevention. The current study sheds new light on the mode of action of resveratrol (RES), a plant-derived polyphenolic compound, against EL-4 lymphoma growth.
  
  
  RESULTS
  Immuno-compromised NOD/SCID mice injected with EL-4 tumor cells and treated with RES (100 mg/kg body weight) showed delayed development and progression of tumor growth and increased mean survival time. RES caused apoptosis in EL4 cells through activation of aryl hydrocarbon receptor (AhR) and upregulation of Fas and FasL expression in vitro. Blocking of RES-induced apoptosis in EL4 cells by FasL mAb, cleavage of caspases and PARP, and release of cytochorme c, demonstrated the participation of both extrinsic and intrinsic pathways of apoptosis. RES also induced upregulation of silent mating type information regulation 2 homolog, 1 (SIRT1) and downregulation of nuclear factor kappa B (NF-κB) in EL4 cells. siRNA-mediated downregulation of SIRT1 in EL4 cells increased the activation of NF-κB but decreased RES-mediated apoptosis, indicating the critical role of SIRT1 in apoptosis via blocking activation of NF-κB.
  
  
  CONCLUSIONS
  These data suggest that RES-induced SIRT1 upregulation promotes tumor cell apoptosis through negative regulation of NF-κB, leading to suppression of tumor growth.
authors.affiliation: Department of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine, University of South Carolina, Columbia, SC 29208, USA.
authors.forename: Narendra P
authors.initials: NP
authors.lastname: Singh
authors.forename: Udai P
authors.initials: UP
authors.lastname: Singh
authors.forename: Venkatesh L
authors.initials: VL
authors.lastname: Hegde
authors.forename: Hongbing
authors.initials: H
authors.lastname: Guan
authors.forename: Lorne
authors.initials: L
authors.lastname: Hofseth
authors.forename: Mitzi
authors.initials: M
authors.lastname: Nagarkatti
authors.forename: Prakash S
authors.initials: PS
authors.lastname: Nagarkatti
mesh_terms: D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D045744:Cell Line, Tumor; D053222:Fas Ligand Protein / Q000235:genetics / Q000502:physiology; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D008223:Lymphoma / Q000188:drug therapy* / Q000473:pathology; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D016328:NF-kappa B / Q000235:genetics*; D018336:Receptors, Aryl Hydrocarbon / Q000235:genetics; D000077185:Resveratrol; D056564:Sirtuin 1 / Q000235:genetics* / Q000502:physiology; D013267:Stilbenes / Q000494:pharmacology*; D019014:fas Receptor / Q000235:genetics
chemical_list: D016588:Anticarcinogenic Agents; D000972:Antineoplastic Agents, Phytogenic; D053222:Fas Ligand Protein; C505658:Fasl protein, mouse; D016328:NF-kappa B; D018336:Receptors, Aryl Hydrocarbon; D013267:Stilbenes; D019014:fas Receptor; C470545:Sirt1 protein, mouse; D056564:Sirtuin 1; D000077185:Resveratrol