Ad·(ST13)·CEA·E1A(Δ24) has been constructed which is a CRC Specific Targeting Gene-Viro-Therapy (CTGVT-CRC) with antitumor effect for three CRC specific cancers higher than that of three CEA-negative cancers while no toxicity to normal cells (Fig. 2A, B). This evidence concerns the gene DHTKD1 and colorectal carcinoma.