SMN1 and malignant colon neoplasm: To investigate the in vivo antitumor effect of SMA and its potential use in combination chemotherapy, we used a CT26 syngenic tumor model and a HT29 xenograft model in mice and compared the effects of SMA with the effects of 5-FU, which is commonly used to treat solid tumors, including colon cancer (drug treatment scheme is shown in Fig 4A).