Delphinidin reduces cell proliferation and induces apoptosis of non-small-cell lung cancer cells by targeting EGFR/VEGFR2 signaling pathways

PLoS One. 2013 Oct 4;8(10):e77270. doi: 10.1371/journal.pone.0077270. eCollection 2013.

Abstract

Epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor 2 (VEGFR2) have emerged as two effective clinical targets for non-small-cell lung cancer (NSCLC). In the present study, we found that delphinidin, an anthocyanidin, present in pigmented fruits and vegetables, is a potent inhibitor of both EGFR and VEGFR2 in NSCLC cells that overexpress EGFR/VEGFR2. Using these cells, we next determined the effects of delphinidin on cell growth and apoptosis in vitro and on tumor growth and angiogenesis in vivo. Delphinidin (5-60 µM) treatment of NSCLC cells inhibited the activation of PI3K, and phosphorylation of AKT and MAPKs. Additionally, treatment of NSCLC cells with delphinidin resulted in inhibition of cell growth without having significant toxic effects on normal human bronchial epithelial cells. Specifically, treatment of NCI-H441 and SK-MES-1 cells with delphindin (5-60 µM) resulted in (i) cleavage of PARP protein, (ii) activation of caspase-3 and -9, (iii) downregulation of anti-apoptotic proteins (Bcl2, Bcl-xL and Mcl-1), (iv) upregulation of pro-apoptotic proteins (Bax and Bak), and (v) decreased expression of PCNA and cyclin D1. Furthermore, in athymic nude mice subcutaneously implanted with human NSCLC cells, delphinidin treatment caused a (i) significant inhibition of tumor growth, (ii) decrease in the expression of markers for cell proliferation (Ki67 and PCNA) and angiogenesis (CD31 and VEGF), and (iii) induction of apoptosis, when compared with control mice. Based on these observations, we suggest that delphinidin, alone or as an adjuvant to current therapies, could be used for the management of NSCLC, especially those that overexpress EGFR and VEGFR2.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anthocyanins / administration & dosage
  • Anthocyanins / pharmacology*
  • Antineoplastic Agents, Phytogenic / administration & dosage
  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Apoptosis / drug effects*
  • Carcinoma, Non-Small-Cell Lung / drug therapy
  • Carcinoma, Non-Small-Cell Lung / metabolism*
  • Carcinoma, Non-Small-Cell Lung / pathology
  • Caspases / metabolism
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Cyclin D1 / metabolism
  • Disease Models, Animal
  • Epidermal Growth Factor / pharmacology
  • ErbB Receptors / metabolism*
  • Female
  • Humans
  • Lung Neoplasms / drug therapy
  • Lung Neoplasms / metabolism*
  • Lung Neoplasms / pathology
  • Mice
  • Mitogen-Activated Protein Kinases / metabolism
  • Neovascularization, Pathologic / drug therapy
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphorylation / drug effects
  • Poly(ADP-ribose) Polymerases / metabolism
  • Proliferating Cell Nuclear Antigen / metabolism
  • Proteolysis / drug effects
  • Proto-Oncogene Proteins c-akt / metabolism
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Signal Transduction / drug effects*
  • Tumor Burden / drug effects
  • Vascular Endothelial Growth Factor A / pharmacology
  • Vascular Endothelial Growth Factor Receptor-2 / metabolism*
  • Xenograft Model Antitumor Assays

Substances

  • Anthocyanins
  • Antineoplastic Agents, Phytogenic
  • Proliferating Cell Nuclear Antigen
  • Proto-Oncogene Proteins c-bcl-2
  • Vascular Endothelial Growth Factor A
  • Cyclin D1
  • Epidermal Growth Factor
  • Poly(ADP-ribose) Polymerases
  • Phosphatidylinositol 3-Kinases
  • ErbB Receptors
  • Vascular Endothelial Growth Factor Receptor-2
  • Proto-Oncogene Proteins c-akt
  • Mitogen-Activated Protein Kinases
  • Caspases
  • delphinidin