Chimeric small molecules for detouring drugs into mitochondria to engender apoptosis in cancer cells

Abstract

Mitochondrion has appeared as one of the important targets for the anti-cancer therapy. Subsequently, small molecule anti-cancer drugs are directed to the mitochondria for improved therapeutic efficacy. However, simultaneous imaging and impairing mitochondria by a single probe remained a major challenge. To address this, herein chimeric small molecules (CSMs) encompassing drugs, fluorophore and mitochondria homing moiety were designed and synthesized through a concise strategy. Screening of the CSMs in a panel of cancer cell lines (HeLa, MCF7, A549 and HCT-116) revealed that one of the CSMs comprising indomethacin V exhibited remarkable cervical cancer cell (HeLa) killing (IC50 = 0.97 μM). This lead CSM homed into the mitochondria of HeLa cells within 1h followed by mitochondrial damage and reactive oxygen species (ROS) generation. This novel indomethacin V-based CSM-mediated mitochondrial damage induced programmed cell death (apoptosis). We anticipate this CSMs can be used as tools to understand the drug effects in organelle chemical biology in diseased states.