The proapoptotic C16-ceramide-dependent pathway requires the death-promoting factor Btf in colon adenocarcinoma cells

J Proteome Res. 2009 Oct;8(10):4810-22. doi: 10.1021/pr9005316.

Abstract

Ceramides are central molecules in sphingolipid metabolism. They are involved in the regulation of cancer-cell growth, differentiation, senescence and apoptosis. To better understand how these secondary messengers induce their biological effects, adenocarcinoma cells (HCT116) were treated with exogenous long-chain ceramides (C16-ceramide) in order to mimic endogenous sphingolipids. This treatment induced a decrease of cell viability partly due to apoptosis as shown by PARP cleavage and a decrease of pro-caspase 3. Two-dimensional differential in-gel electrophoresis (2D-DIGE) revealed the differential expression of 51 proteins in response to C16-ceramide. These proteins are notably involved in cell proliferation, apoptosis, protein transport and transcriptional regulation. Among them, the cell death-promoting factor Btf was found to be implicated in the apoptotic signal triggered by ceramide. In adenocarcinoma cells, Btf regulates apoptosis related proteins such as Mdm2, p53, BAX and pBcl-2 and thus plays an important role in the ceramide mediated cell death. These findings bring new insight into the proapoptotic ceramide-dependent signaling pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / metabolism*
  • Apoptosis / drug effects
  • Cell Survival
  • Ceramides / pharmacology*
  • Colonic Neoplasms / metabolism*
  • Electrophoresis, Gel, Two-Dimensional
  • HCT116 Cells
  • Humans
  • Proteome / drug effects
  • Proteome / metabolism
  • Proteomics / methods*
  • Proto-Oncogene Proteins c-mdm2 / metabolism
  • Repressor Proteins / metabolism*
  • Reproducibility of Results
  • Signal Transduction
  • Tandem Mass Spectrometry
  • Tumor Suppressor Protein p53 / metabolism
  • Tumor Suppressor Proteins / metabolism*
  • bcl-2-Associated X Protein / metabolism

Substances

  • BAX protein, human
  • BCLAF1 protein, human
  • Ceramides
  • Proteome
  • Repressor Proteins
  • TP53 protein, human
  • Tumor Suppressor Protein p53
  • Tumor Suppressor Proteins
  • bcl-2-Associated X Protein
  • N-palmitoylsphingosine
  • MDM2 protein, human
  • Proto-Oncogene Proteins c-mdm2