RESUMEN
<p><b>OBJECTIVE</b>To investigate the effect of recombinant adenovirus (phosphatidylinositol-3-kinases(PI3K)(I()-RNAi-AD which blocks the class I( PI3K signaling pathway on gastric carcinoma cells xenografts in nude mice.</p><p><b>METHODS</b>Subcutaneous tumor models of nude mice were established with SGC7901 cells and randomly divided into PI3K(I()-RNAi-AD group, NC-RNAi-GFP-AD group and control group. The tumor size and the inhibitory rate of tumor growth on days 3, 6, and 9 after cell transplantation were measured. The expression of TNF-α, COX2, P53, PCNA, E-cadherin and nm23/DNPK in tumor tissues were detected by immunohistochemistry.</p><p><b>RESULTS</b>Tumor growth was significantly inhibited in the PI3K(I()-RNAi-AD group(14.2%, 21.0%, and 28.1%) on days 3, 6, 9 compared with NC-RNAi-GFP-AD group(1.3%, 1.9%, and 2.0%, all P<0.05). The expressions of TNF-α, P53, E-cadherin and nm23/DNPK were up-regulated, and the expressions of COX2 and PCNA were down-regulated in the PI3K(I()-RNAi-AD group by immunohistochemical staining(all P<0.05).</p><p><b>CONCLUSIONS</b>PI3K(I()-RNAi-AD can inhibit the growth of SGC7901 cell transplantation tumor in vivo in nude mice by inhibiting cell growth, reducing the capacity of tumor invasion and inhibiting tumor angiogenesis.</p>