Inhibitory effects of E2F decoy ODNs on OP18 gene expression and proliferation in gastric cancer MKN-45 cells

AIM: To investigate the blocking effects of E2F decoy oligodeoxynucleotides (ODNs) in dumbbell shape on the op18 gene transcription and the gastric cancer MKN-45 cell proliferation. METHODS: E2F decoy ODNs were designed, chemically synthesized, annealed and ligated to form dumbbell shape, and then transfected into gastric cancer cell line MKN-45 using lipofectamineTM2000 reagent according to the manufacturer's instructions. Total RNA was extracted by using TRIzol. The level of op18 mRNA in the transfected tumor cells was detected by RT-PCR.The proliferation of the transfected tumor cells was analyzed by MTT assay and the apoptosis of the tumor cells was detected by TUNEL staining. RESULTS: E2F decoy ODNs could be successfully transfected into tumor cells, and RT-PCR results indicated that E2F decoy ODNs decreased the expression of op18 gene in the transfected tumor cells. The proliferation of tumor cells was inhibited markedly by E2F decoy ODNs and morphological analysis showed positive staining identified by TUNEL assay. CONCLUSION: E2F decoy ODNs in dumbbell shape may specifically decrease the activity of transcription factor E2F and down-regulate op18 gene expression and inhibit MKN-45 cell proliferation, which demonstrates a potential strategy for cancer gene therapy.