ABSTRACT
Objective To observe the effect of inhibition of polo like kinasel (Plk-1) gene expression on 5-Fu and CDDP induced apoptosis of gastric cancer cell line-MKN45 in vitro. Methods The Plk-1 expression was inhibited by chemically synthesized siRNA, the Plk-1 mRNA and protein level were measured by real-time PCR and Western blotting, MKN45 cells proliferation was measured by MTT method, the apoptosis rate was detected by flow-cytometry. Results After treatment by siRNA targeting Plk-1, Plk-1 mRNA level decreased by 51.91% .89.45%.91.03% at 24 h.48 h and 72 h, and Plk-1 protein level decreased by 38.43% and 60.66% at 48 h and 72 h, compared with control group. The proliferation of MKN45 cells treated by a combination of 5-Fu, CDDP and Plk-1 siRNA significantly slowed down when compared with treatment of 5-Fu, CDDP or Plk-1 siRNA(P