Objective:To preliminarily investigate the effect of RNA interference targeting GM130 on O-linked glycosylation and adhesion of human gastric cancer cell line MKN-45. Methods:GM130-si RNA was transfected into human gastric cancer cell line MKN-45 with Lipofectamine 2000. The experiment had three groups :GM130-si RNA group

negative control group and blanck control group. The expressions of GM130

pp Gal NAc-T2

C1Gal-T1

ST3Gal-1 at m RNA and protein levels in the MKN-45 cells were analyzed by real-time PCR and Western blot. The expressions of α2

3-linked sialic acid residues in MKN-45 cell surface were detected by flow cytometry. The changes in the adhesion of the transfected cells were tested with matrigel adhesion and tumor cell adhere to the vascular endothelial cell assay. Results:The real-time PCR and Western blot results showed that the m RNA and protein expression levels of GM130 decreased significantly in gastric cancer cell line MKN-45 transfected with GM130-si RNA

indicating a successful transfection. Compared with those in blank and negative control groups

both the m RNA transcription and protein expression levels of C1Gal-T1

ST3Gal-1 in MKN-45 cells transfected with GM130-si RNA decreased significantly(P<0.05)

but those of pp Gal NAcT2 were not significantly affected(P>0.05). The expression levels of α2

3-linked sialic acid residues were decreased(P<0.05)

and the cell adhesion was apparently reduced(P<0.05). Conclusion:The GM130 may play an important role in O-linked glycosylation of MKN-45;the molecular mechanism might be associated with down-regulating C1Gal-T1

ST3Gal-1 expression and downregulation of GM130 decreasd gastric cancer cell adhesion.