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. The gene discussed is TKT; the disease is colonic neoplasm.