Objective    To detect the effect of osteopontin (OPN) siRNA on the growth

invasion and apoptosis of human gastric cancer cell line MKN28.     Methods    The eukaryotic expression vector of siRNA specific for OPN was constructed by liposome transfection

and the silencing effect was identified by fluorescence quantitative PCR and immunofluorescence staining. According to the inhibitory effect of the siRNA vectors

the experiment was divided into control group

non-specific OPN siRNA group

24-hour specific OPN siRNA group

36-hour specific OPN siRNA group

and 48-hour specific OPN siRNA group. The cell proliferation

apoptosis

migration and adhesion was finally detected among control group and OPN siRNA groups at different time points.     Results    For 48-hour specific OPN siRNA group

the expression of OPN in MKN28 cells was the lowest. Accordingly

the cell viability was decreased and the cell proliferation inhibitory rate was reduced to 30.20%; the ability of migration and adhesion was decreased

the number of cells attached on stromal cell membrane was much lesser (21.8±6.9 vs 42.0±9.4 in control group)

and the ratio of cell adhesion on basement membrane matrix and fibronectin was lower [basement membrane matrix: (41.5±8.4)% vs (20.5±4.5)%; fibronectin: (25.3±4.5)% vs (14.6±2.5)% in control group]

as well as the cell apoptotic rate was increased compared with the control group.     Conclusion    OPN gene silencing can inhibit the growth and invasion

as well as accelerate apoptosis in human gastric cancer MKN28 cells.