Bcl-2 promotes invasion and lung metastasis by inducing matrix metalloproteinase-2

Cancer Res. 2005 Jul 1;65(13):5554-60. doi: 10.1158/0008-5472.CAN-04-4570.

Abstract

Bcl-2 is involved in the progression of human malignancies, but the precise role and mechanism of Bcl-2 for tumor invasion and metastasis remains unclear. In this study, we have investigated the role and mechanism of Bcl-2 on tumor cell invasion and metastasis by using Bcl-2 overexpressing non-small cell lung cancer cells. Matrix metalloproteinases (MMPs) are important proteins involved in the processes of tumor invasion and metastasis. In vitro Matrigel invasion assays showed that Bcl-2 overexpression increased tumor cell invasion by 15-fold. Moreover, Bcl-2 overexpression enhanced in vivo lung metastasis by 4-fold. Consistent with its effect on invasion and metastasis, Bcl-2 overexpression induced not only MMP-2 mRNA and its protein expression, but this also activated the pro-MMP-2 protein to its active form. To explore the induction mechanism of MMP-2 by Bcl-2, we investigated the effects of Bcl-2 overexpression on MMP-2 transcriptional regulation. Nuclear run-on assays showed a 6-fold increase in the transcription rate of MMP-2 mRNA in the Bcl-2 transfectants (H157/Bcl-2) compared with that of the H157/vector control cells (H157/C). Overexpression of Bcl-2 induced the nuclear transcription factor activator protein 1 family, including the c-Jun, JunD, c-Fos, FosB, and Fra-1 proteins. Reporter assays combined with deletion mutagenesis analysis and gel shift assays showed the involvement of activator protein 1 in the activation of MMP-2 promoter activity by Bcl-2. Taken together, we have shown that Bcl-2 promotes tumor invasion and lung metastasis by inducing MMP-2 gene expression through the combined action of transcriptional and posttranslational mechanisms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Binding Sites
  • Carcinoma, Non-Small-Cell Lung / enzymology*
  • Carcinoma, Non-Small-Cell Lung / genetics
  • Carcinoma, Non-Small-Cell Lung / pathology*
  • Enzyme Activation
  • Enzyme Induction
  • Female
  • Humans
  • Lung Neoplasms / enzymology*
  • Lung Neoplasms / genetics
  • Lung Neoplasms / pathology*
  • Matrix Metalloproteinase 2 / biosynthesis*
  • Matrix Metalloproteinase 2 / genetics
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • Neoplasm Invasiveness
  • Neoplasm Metastasis
  • Promoter Regions, Genetic
  • Proto-Oncogene Proteins c-bcl-2 / biosynthesis
  • Proto-Oncogene Proteins c-bcl-2 / genetics
  • Proto-Oncogene Proteins c-bcl-2 / physiology*
  • Transcription Factor AP-1 / biosynthesis
  • Transcription Factor AP-1 / metabolism
  • Transcriptional Activation
  • Transfection

Substances

  • Proto-Oncogene Proteins c-bcl-2
  • Transcription Factor AP-1
  • Matrix Metalloproteinase 2