RNAi-mediated silencing of VEGF-C inhibits non-small cell lung cancer progression by simultaneously down-regulating the CXCR4, CCR7, VEGFR-2 and VEGFR-3-dependent axes-induced ERK, p38 and AKT signalling pathways

Eur J Cancer. 2011 Oct;47(15):2353-63. doi: 10.1016/j.ejca.2011.05.006. Epub 2011 Jun 15.

Abstract

Vascular endothelial growth factor C (VEGF-C) expression is associated with the malignant tumour phenotype making it an attractive therapeutic target. We investigated the biological roles of VEGF-C in tumour growth, migration, invasion and explored the possibility of VEGF-C as a potential therapeutic target for the treatment of non-small cell lung cancer (NSCLC). A lentivirus-mediated RNA interference (RNAi) technology was used to specifically knockdown the expression of VEGF-C in A549 cells. Quantitative reverse transcriptase-polymerase chain reaction, flow cytometry, Western blot, immunohistochemistry, cellular growth, migration, invasion and ELISA assays were used to characterise VEGF-C expression in vitro. A lung cancer xenograft model in nude mice was established to investigate whether knockdown of VEGF-C reduced tumour growth in vivo. Silencing of VEGF-C suppressed tumour cell growth, migration and invasion in vitro; suppressed tumour growth, angiogenesis and lymphangiogenesis by tail vein injection of lentivirus encoded shRNA against VEGF-C in vivo. More importantly, silencing of VEGF-C also trapped the VEGFR-2, VEGFR-3, CXCR4, CCR7-dependent axes, and down-regulated the AKT, ERK and p38 signalling pathways. These results suggest that VEGF-C has a multifaceted role in NSCLC growth, migration and invasion; that VEGF-C-mediated autocrine loops with their cognate receptors and chemokine receptors are significant factors affecting tumour progression; and that RNAi-mediated silencing of VEGF-C represents a powerful therapeutic approach for controlling NSCLC growth and metastasis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • Blotting, Western
  • Carcinoma, Non-Small-Cell Lung / blood supply
  • Carcinoma, Non-Small-Cell Lung / enzymology
  • Carcinoma, Non-Small-Cell Lung / genetics
  • Carcinoma, Non-Small-Cell Lung / pathology
  • Carcinoma, Non-Small-Cell Lung / therapy*
  • Cell Line, Tumor
  • Cell Movement
  • Cell Proliferation
  • Down-Regulation
  • Enzyme-Linked Immunosorbent Assay
  • Extracellular Signal-Regulated MAP Kinases / metabolism*
  • Flow Cytometry
  • Genotype
  • Humans
  • Immunohistochemistry
  • Lung Neoplasms / blood supply
  • Lung Neoplasms / enzymology
  • Lung Neoplasms / genetics
  • Lung Neoplasms / pathology
  • Lung Neoplasms / therapy*
  • Lymphangiogenesis
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • Molecular Sequence Data
  • Neoplasm Invasiveness
  • Neovascularization, Pathologic / enzymology
  • Neovascularization, Pathologic / prevention & control
  • Phenotype
  • Proto-Oncogene Proteins c-akt / metabolism*
  • RNA Interference*
  • Receptors, CCR7 / metabolism*
  • Receptors, CXCR4 / metabolism*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Signal Transduction
  • Time Factors
  • Transfection
  • Tumor Burden
  • Vascular Endothelial Growth Factor C / genetics
  • Vascular Endothelial Growth Factor C / metabolism*
  • Vascular Endothelial Growth Factor Receptor-2 / metabolism*
  • Vascular Endothelial Growth Factor Receptor-3 / metabolism*
  • Xenograft Model Antitumor Assays
  • p38 Mitogen-Activated Protein Kinases / metabolism*

Substances

  • CCR7 protein, human
  • CXCR4 protein, human
  • Receptors, CCR7
  • Receptors, CXCR4
  • VEGFC protein, human
  • Vascular Endothelial Growth Factor C
  • Vascular Endothelial Growth Factor Receptor-2
  • Vascular Endothelial Growth Factor Receptor-3
  • Proto-Oncogene Proteins c-akt
  • Extracellular Signal-Regulated MAP Kinases
  • p38 Mitogen-Activated Protein Kinases