Codelivery of dihydroartemisinin and chlorin e6 by copolymer nanoparticles enables boosting photodynamic therapy of breast cancer with low-power irradiation

Given that chemotherapy as a stand-alone therapeutic strategy may not be sufficient to effectively treat cancer,there is increasing interest in combination of chemotherapy and alternative therapies.Photodynamic therapy has the advantages of high selectivity and low side effects,so the combination of photodynamic therapy and chemotherapy has become one of the most appealing strategies for tumor treatment.In this work,we constructed a nano drug codelivery system(PPDC)to realize the combined treatment of chemotherapy and photodynamic therapy through encapsulating chemotherapeutic drug dihydroartemisinin and photosensitizer chlorin e6 in PEG-PCL.The potentials,particle size and morphology of nanoparticles were characterized by dynamic light scattering and transmission electron microscopy.We also investigated the reactive oxygen species(ROS)generation and drug release ability.The antitumor effect in vitro was investigated by methylthiazolyldiphenyl-tetrazolium bromide assays and cell apoptosis experiments,and the potential cell death mechanisms were explored by ROS detection and Western blot analysis.The in vivo antitumor effect of PPDC was evaluated under the guidance of fluorescence imaging.Our work provides a potential antitumor treatment approach and expands the application of dihydroartemisinin for breast cancer therapy.

Emerging non-antibody‒drug conjugates (non-ADCs) therapeutics of toxins for cancer treatment

The non-selective cytotoxicity of toxins limits the clinical relevance of the toxins.In recent years,toxins have been widely used as warheads for antibody-drug conjugates(ADCs)due to their eff-cient killing activity against various cancer cells.Although ADCs confer certain targeting properties to the toxins,low drug loading capacity,possible immunogenicity,and other drawbacks also limit the po-tential application of ADCs.Recently,non-ADC delivery strategies for toxins have been extensively investigated.To further understand the application of toxins in anti-tumor,this paper provided an over-view of prodrugs,nanodrug delivery systems,and biomimetic drug delivery systems.In addition,toxins and their combination strategies with other therapies were discussed.Finally,the prospect and challenge of toxins in cancertreatmentwerealso summarized.