Figure 1

Downregulated mitochondrial phosphoenolpyruvate carboxykinase (mPEPCK) in the human colon cancer cell line SNU-C4R with induced 5-FU resistance. (a) Selection of downregulated protein spot on 2-DE gel images. By comparing the 2-DE gel images, a ~100-kDa protein was identified as being downregulated in SNU-C4R. (b) Identification of mPEPCK by MALDI-MS analysis. The selected protein spot was identified as mPEPCK. (c) Western Blot analysis for confirmation of downregulation of mPEPCK in SNU-C4R. Total PEPCK (cytosolic and mitochondrial isoforms) and mPEPCK expression was significantly lower in SNU-C4R than in its parent cell line SNU-C4.