Survivin antisense oligodeoxynucleotide inhibits growth of gastric cancer cells

Abstract

Aim: To investigate the effect of transfected survivin antisense oligonucleotide (ASODN) on proliferation and apoptosis of gastric cancer cells.

Methods: The authors designed ASODNs targeting different regions of survivin mRNA, including surviving ASODN1, ASODN2 and ASODN3. ASODNs were transfected into gastric cancer cell line SGC 7901, cell growth was detected by MTT assay. Cells exposed to the potent oligonucleotide were also examined for apoptosis induction by FCM and fluorescence microscopy. Semiquantitive RT-PCR and Western blot examinations were carried for expression of survivin mRNA and protein.

Results: ASODN3 caused a statistically significant reduction of cell viability to 60.6% (+/-2.9%) (P<0.01), while ASODN1 and ASODN2 had no such changes (P>0.05). The cell growth was also significantly inhibited by ASODN3, compared with reversal and scrambled sequence. A significant loss of survivin mRNA was presented in ASODN3 treated cells and this was not seen in treatment with sense ODN or scramble ODN. Protein level was significantly decreased 48 h after survivin ASODN trasfected by approximately 2-fold decrease compared with untreated controls. However, ASODN3 did not induce significant apoptosis response until 48 h after transfection (P>0.05).

Conclusion: ASODN3, which targets translation initiation part, can be identified as a most potent antisense compound. Srvivin ASODN3 may provide a novel approach to therapy of gastric cancer.

Figure 1

Cytotoxic effect of ASODN targeting different regions of survivin mRNA. Cells were cultured in plastic 96-well plates and quantitated using MTT assay as described in “Materials and Methods.”

Figure 2

Cytotoxic effect of ASODN3 and control sequences.

Figure 3

Survivin and β-actin (loading control) mRNA ex-pression following incubation with antisense, sense,scramble and no ODN control. It shows ethidium bromide staining of conventional agarose gel electrophoresis after amplification.

Figure 4

Survivin protein expression following incubation with surviivn, antisense, sense, scramble and no ODN control. Strong decrease of survivin protein could be detected in the ASODN group.