Credit: @Science China Press Cancer is the second leading cause of death in the world. The number of deaths and incidences is increasing each year. The metal-based anticancer drugs were used clinically worldwide, but suffer from poor selectivity, serious side effects and drug resistance. Tumor-targeting drug development is the basis for precise cancer treatment. Recently, Professor Hongke Liu of Nanjing Normal University, Professor Jing Zhao and Academician Zijian Guo of Nanjing University have made breakthrough achievements in anticancer drug development. They proposed a "bio-orthogonally catalyzed lethality" (BCL) strategy (Figure 1) and published their results in "National Science Review" (National Science Review, NSR). The BCL strategy uses tumors as manufacturing factories to generate a highly potential tumor-targeted drug Ru-rhein, which can selectively kill cancer cells and tumors in tumor-bearing mice, while no toxicity on normal cells. BCL strategy generates targeting drugs from non-toxic compounds within the tumor, not only avoiding the decomposition and inactivation of the drug during transportation and storage, but also reducing the serious side effects caused by interacting with biologically active molecules during treatment.