Conjugated polymers as multifunctional biomedical platforms: Anticancer activity and apoptosis imaging

Abstract

Recent advances in biological applications of conjugated polymers have focused on highly sensitive diagnostics. The therapeutics of conjugated polymers, however, remains a challenging task. Here we explore for the first time that cationic polythiophene (PMNT) is used as a multifunctional agent for simultaneous cancer therapeutic and apoptosis imaging applications. The anticancer mechanism study showed that the PMNT can uptake inside renal cell carcinoma (A498) cancer cells in a diffusion manner and induce their apoptosis. The increased activation of caspase-3 have been shown to be time- and dose-dependent on PMNT, which indicates a signaling transduction pathway of PMNT induced-apoptosis in A498 cells. Beyond conventional endpoint analysis of apoptosis using multiplex dyes, the PMNT can image the cells and clearly distinguish the living and apoptotic cancer cells. Strikingly, the PMNT could quickly induce cell apoptosis within several minutes under irradiation. The PMNT integrates photosensitivity, anticancer activity and apoptosis imaging, which opens the door for new functional studies of conjugated polymers in disease therapeutics.