N-glycosylation modification of proteins is an early marker of the enterocytic differentiation process of HT-29 cells.
The human colon cancer cell line HT-29 remains totally undifferentiated when glucose is present in the culture medium (HT-29 Glc+), while the same cells may undergo typical enterocytic differentiation after reaching confluence when grown in glucose-deprived medium (HT-29 Glc-). Recently, we demonstrated a deficiency in the overall N-glycan processing in confluent undifferentiated cells, whereas differentiated cells follow a classical pattern of N-glycosylation. The main changes in N-glycosylation observed in confluent undifferentiated cells may be summarised as follows: 1) the conversion of high mannose into complex glycopeptides is greatly decreased; 2) this decreased conversion could be a consequence of an accumulation of Man9-8-GlcNAc2-Asn high mannose species. Whether these changes in N-glycan processing appear progressively during cell culture or are already present from the beginning of the culture was investigated in this study by comparing the actual status of N-glycan processing in exponentially growing HT-29 Glc- and HT-29 Glc+ cells. Under these conditions, HT-29 Glc- cells do not exhibit any characteristics of differentiation. The conversion of high mannose into complex glycoproteins is severely reduced in HT-29 Glc+ cells, regardless of the growth phase studied. In contrast, HT-29 Glc- cells display a normal pattern of N-glycan processing in both growth phases. We therefore conclude that N-glycan processing may be used as an early biochemical marker of the enterocytic differentiation process of HT-29 cells.
UFR Biomédicale des Saint-Péres, INSERM U180, Unité de Recherches sur la Biologie et Pathologie Moléculaires des Glycoprotéines, Paris, France.
E
E
Ogier-Denis
C
C
Bauvy
M
M
Aubery
P
P
Codogno
C
C
Sapin
D
D
Darmoul
A
A
Zweibaum
G
G
Trugnan
D002454:Cell Differentiation; D002455:Cell Division; D003110:Colonic Neoplasms / Q000378:metabolism / Q000473:pathology*; D005947:Glucose / Q000378:metabolism; D006031:Glycosylation; D006801:Humans; D007422:Intestines / Q000473:pathology*; D008358:Mannose / Q000378:metabolism; D011134:Polysaccharides / Q000378:metabolism; D011506:Proteins / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D011134:Polysaccharides; D011506:Proteins; D005947:Glucose; D008358:Mannose