Commonly used suicide gene/prodrug combinations HSV‐tk/GCV and UPRT/5‐FU have already been applied for clinical studies of diseases such as brain tumor, ovarian cancer, and colon cancer.24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34. Here, TKT is linked to malignant colon neoplasm.