CASP3 and neoplasm: Exhilaratingly, tumor microenvironments (acidic milieu, high GSH concentration, and over‐expressed enzyme of cancer cells) provide an attractive opportunity to achieve this goal.13 Liang and co‐workers14 prepared a caspase 3‐instructed aggregation of Fe3O4@1 NPs by using an enzyme‐instructed condensation reaction, which hold a specificity for T2 enhanced MR imaging in tumor apoptosis and might be applied to detect the chemotherapeutic efficiency of tumors in routine preclinical studies in near future.