The Effects of Adenovirus-Mediated Human cox-2 Antisense RNA on Growth of Esophgeal Carcinoma Cells

Objective: To construct the recombinant adenovirus encoding human cox-2 antisense RNA and to investigate its effects on proliferation of tumor cells. Methods: The shuttle plasmid encoding antisense cox-2 was constructed by cloning cox-2 cDNA fragment in the reverse direction into the pHCMVSP1A. Then the plasmid pJM17 and the shuttle plasmid were cotransferred into 293 cells with lipofectamine for homologous recombinantion to acquire recombinant adenovirus which was confirmed by PCR . We evaluated how alterations of cox-2 expression in EC9706 cells transfected with adenovirus-mediated human cox-2 antisense RNA expression (Ad-AShcox-2) or adenovirus recombinants carrying LacZ gene (Ad-LacZ), and its effects on cell proliferation were determined by cell growth rate, 3 H-TdR incorporation and immunohistochemistry. Results: The recombinant adenovirus encoding antisense cox-2 fragment Ad-AShcox-2 was obtained with the titer of 0.86 10 12 PFU/ml. Ad-AShcox-2 could reduce the expression of cox-2 , and strongly inhibit cell growth rate and cause cellular death. Simultaneously, 3 H-TdR incorporation was lower than that of control group ( P 0.001) Conclusion: Reduction of cox-2 expression could inhibit esophageal cancer proliferation through inhibiting the synthesis of DNA.