Previously, an SW480 nude mouse subcutaneous transplanted tumor model was established and the wild type (WT) p53 gene was combined with thymidine kinase/ganciclovir (TK/GCV) and cytosine deaminase/5-fluorocytosine (CD/5-FC) systems, which were shown to significantly inhibit the growth of subcutaneous transplanted tumors and prolong the survival of mice (8). Here, TP53 is linked to neoplasm.