The SW620 xenograft model for human colorectal tumors was established in athymic nude mice to assess the potential antitumor efficacy of Ad·(ST13)·CEA·E1A(Δ24) in vivo. As shown in Fig. 5A, the tumors grew rapidly in the PBS-treated group, whereas various degrees of tumor growth suppression were observed in the ONYX-015-, Ad·(EGFP)·CEA·E1A(Δ24)- and Ad (ST13)·CEA·E1A(Δ24)-treated groups. Here, DHTKD1 is linked to neoplasm.