Discovery of DNA Topoisomerase I Inhibitors with Low-Cytotoxicity Based on Virtual Screening from Natural Products oleh Lan-Ting Xin, Lu Liu, Chang-Lun Shao, Ri-Lei Yu, Fang-Ling Chen, Shi-Jun Yue, Mei Wang, Zhong-Long Guo, Ya-Chu Fan, Hua-Shi Guan, Chang-Yun Wang