Proteomic fingerprinting of N-linked glycoproteins involved in hepatocellular carcinoma / 解剖学报

ABSTRACT

Objective To identify differentially expressed N-linked glycoproteins between hepatocellular carcinoma ( HCC) and adjacent non-tumorous liver tissues .Methods N-linked glycoproteome was extracted by multi-lectin affinity chromatography comprising concanavalin A (ConA), lentil lectin (LCH), and snowdrop lectin (GNA) and subsequently subjected to two-dimensional electrophoresis ( 2DE ) and mass spectrometry ( MS ) for identification of differential glycoproteins between 10 pairs of HCC and adjacent non-cancer tissue .Western blotting was used to verify different expression of human liver carboxylesterase 1 (hCE1), haptoglobin (HP)and cathepsin D (CD).Invasion potential in vitro was examined after si-RNA mediated CD gene scilencing .Results LC-ESI-MS/MS identified a total of 28 differentially expressed glycoproteins (14 up-regulation and 14 down-regulated).Western blotting detected consistent down-regulation of hCE1 and HP, and up-regulation of pro-cathepsin D (pCD) in HCC.Up-regulation of ConA-binding CD (ConA-CD), however , was verified in HCC only after ConA-CD enrichment by ConA chromatography .Down-regulation of CD expression mediated by CD-siRNA markedly inhibited the in vitro invasive potential of SNU449 and SNU473.Conclusion Dysregulation of HP , hCE1 expression and alteration of glycans linked to CD may play crucial roles in pathogenesis of HCC.