phytochlorin and epigallocatechin-gallate

The development of intelligent and precise cancer therapy systems that enable accurate diagnosis and specific elimination of cancer cells while protecting normal cells to improve the safety and effectiveness of the treatment is still a challenge. Herein, we report a novel activatable nanodevice for precise cancer therapy. The nanodevice is constructed by adsorbing a DNA duplex probe onto MnO2 nanosheets. After cellular uptake, the DNA duplex probe undergoes telomerase-triggered conformation switching, resulting in a Ce6 "turn-on" signal for the identification of cancer cells. Furthermore, Deoxyribozyme (DNAzyme) is activated to catalyse the cleavage of survivin mRNA, actualizing a precise synergistic therapy in cancer cells involving photodynamic therapy and gene-silencing. The MnO2 nanosheets provide Mn2+ for the DNAzyme and relieve hypoxia to improve the efficiency of the photodynamic therapy. Live cell studies reveal that this nanodevice can diagnose cancer cells and specifically eliminate them without harming normal cells, so making the treatment safer and more effective. The developed DNA-MnO2 nanodevice provides a valuable and general platform for precise cancer therapy.

Topics: Catechin; Cell Line, Tumor; Cell Survival; Chlorophyllides; DNA; DNA, Catalytic; Gene Silencing; Humans; Light; Manganese Compounds; Nanostructures; Neoplasms; Oxides; Photochemotherapy; Photosensitizing Agents; Porphyrins; RNA, Messenger; Survivin; Telomerase

Recently, rapid acquisition of antibiotic resistance, increased prevalence of antibiotic-resistant bacterial infections, and slow healing of infected wound have led to vast difficulties in developing innovative antimicrobial agents to obliterate pathogenic bacteria and simultaneously accelerate wound healing. To effectively solve this problem, we designed light-responsive multifunctional nanoparticles with conjugation of quaternary ammonium chitosan and photosensitizer chlorin e6 (Ce6) to merge chemical and photodynamic therapy to efficient antibacteria. The Mg/(-)-epigallocatechin-3-gallate (EGCG) complex rapidly responded to light irradiation under 660 nm with release of magnesium ions, which effectively accelerated wound healing without toxicity to mammalian cells. Notably, positively charged nanoparticles could efficiently adhere to the bacterial surface, and reactive oxygen species (ROS) produced under laser irradiation destroyed the membrane structure of the bacteria, which is irreversible, ultimately leading to bacteria death. Thus, multifunctional nanoparticles with a combination of chemical and photodynamic antimicrobial therapy would offer guidance to rational predicted and designed new effective antimicrobial nanomaterials. Most importantly, it may represent a promising class of antimicrobial strategy for potential clinical translation.

Topics: Animals; Anti-Infective Agents; Catechin; Cell Line; Chlorophyllides; Delayed-Action Preparations; Escherichia coli; Magnesium; Mice; Nanoparticles; Photochemotherapy; Porphyrins; Rats; Staphylococcal Infections; Staphylococcus aureus; Wound Healing; Wound Infection