Endocytosis of resveratrol via lipid rafts and activation of downstream signaling pathways in cancer cells

Cancer Prev Res (Phila). 2011 Jul;4(7):1095-106. doi: 10.1158/1940-6207.CAPR-10-0274. Epub 2011 Apr 5.

Abstract

trans-Resveratrol has been proposed to prevent tumor growth and to sensitize cancer cells to anticancer agents. Polyphenol entry into the cells has remained poorly understood. Here, we show that [(3)H]-resveratrol enters colon cancer cells (SW480, SW620, HT29) and leukemia U937 cells through a monensin (5-20 μmol/L) -sensitive process that suggests clathrin-independent endocytosis. Uptake of the molecule can be prevented by methyl-β-cyclodextrin (2-12 mg/mL), nystatin (12 ng/mL), and filipin (1 μg/mL), which all disrupt plasma membrane lipid rafts. Accordingly, radiolabeled resveratrol accumulates in sphingomyelin- and cholesterol-enriched cell fractions. Interestingly, extracellular signal-regulated kinases (ERK), c-Jun NH(2)-terminal kinases (JNK), and Akt also accumulate in lipid rafts on resveratrol exposure (IC(50) at 48 h ≈ 30 μmol/L in SW480 and U937 cells). In these rafts also, resveratrol promotes the recruitment, by the integrin α(V)β(3) (revealed by coimmunoprecipitation with an anti-integrin α(V)β(3) antibody), of signaling molecules that include the FAK (focal adhesion kinase), Fyn, Grb2, Ras, and SOS proteins. Resveratrol-induced activation of downstream signaling pathways and caspase-dependent apoptosis is prevented by endocytosis inhibitors, lipid raft-disrupting molecules, and the integrin antagonist peptide arginine-glycine-aspartate (500 nmol/L). Altogether, these data show the role played by lipid rafts in resveratrol endocytosis and activation of downstream pathways leading to cell death.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Antibodies, Monoclonal / pharmacology
  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Apoptosis / drug effects
  • Blotting, Western
  • Colonic Neoplasms / drug therapy*
  • Endocytosis / physiology*
  • Extracellular Signal-Regulated MAP Kinases / metabolism
  • Filipin / pharmacology
  • Flow Cytometry
  • Focal Adhesion Kinase 1 / metabolism
  • GRB2 Adaptor Protein / metabolism
  • Humans
  • Immunoenzyme Techniques
  • Immunoprecipitation
  • Integrin alphaVbeta3 / immunology
  • Integrin alphaVbeta3 / metabolism
  • Membrane Microdomains / physiology*
  • Nystatin / pharmacology
  • Proto-Oncogene Proteins c-akt / metabolism
  • Proto-Oncogene Proteins c-fyn / metabolism
  • Resveratrol
  • Signal Transduction / drug effects*
  • Son of Sevenless Proteins / metabolism
  • Stilbenes / pharmacology*
  • Tumor Cells, Cultured
  • beta-Cyclodextrins / pharmacology
  • ras Proteins / metabolism

Substances

  • Anti-Bacterial Agents
  • Antibodies, Monoclonal
  • Antineoplastic Agents, Phytogenic
  • GRB2 Adaptor Protein
  • GRB2 protein, human
  • Integrin alphaVbeta3
  • Son of Sevenless Proteins
  • Stilbenes
  • beta-Cyclodextrins
  • methyl-beta-cyclodextrin
  • Nystatin
  • Filipin
  • Focal Adhesion Kinase 1
  • PTK2 protein, human
  • Proto-Oncogene Proteins c-fyn
  • Proto-Oncogene Proteins c-akt
  • Extracellular Signal-Regulated MAP Kinases
  • ras Proteins
  • Resveratrol