Objective:To construct a replication-deficient adenovirus carrying p16 gene and to investigate its anti-tumor activity on human gastric cancer xenografts in nude mice.Methods:p16 cDNA was amplified by PCR and was inserted into the plasmid pSuCMV,the latter was then used to recombine the replication-deficient adenovirus AdCMV-p16 in 293 cells.Human SGC-7901 gastric cancer xenograft models were established in nude mice and were divided into 3 groups:AdCMV-p16,Ad-LacZ,and control groups.Mice in AdCMV-p16 group received intratumoral injections of 2?108 pfu/100 l AdCMV-p16(injected every other day for 5 times).Mice in control group received the same volume of virus preserving solution.The tumor volumes were measured at predefined time points.The anti-tumor effect of AdCMV-p16 was observed by p16 immunochemical study and TUNEL detection of cell apoptosis.Results:The replication-deficient adenovirus expressing p16 gene evidently inhibited the growth of human gastric cancer xenografts in nude mice(P0.05),only with a inhibition rate of 4.26%.The pathological examination showed that apoptoses were the main changes in AdCMV-p16 group,and p16 gene was found in the cancer cells.Conclusion:The replication-deficient adenovirus harboring p16 gene can recover the expression of p16 in gastric cancer cells and subsequently inhibit the growth of human gastric cancer.