A Near-Infrared II\nLuminogen with a Photothermal Effect\ntoward Tumor Drug Resistance Reversal

Multidrug resistance of tumor cells has greatly limited\nthe chemotherapy\neffect. The development of reliable strategies to deal with tumor\nmultidrug resistance is highly desirable for tumor therapy. In this\nwork, a near-infrared II (NIR II) luminogen was rationally designed\nand prepared, which could act as a photothermal reagent to reverse\nthe drug resistance of tumor cells by reducing the related protein\nexpression, achieving a high inhibition efficiency with the synergistic\neffect of chemotherapeutic drugs. By the selection of a strong electron-withdrawing\nunit, the emission peak of the luminogen could reach 973 nm. Moreover,\nthis luminogen shows outstanding photothermal conversion ability and\nimproved thermal stability compared to ICG. Notably, after the photothermal\ntreatment of drug-resistant tumor cells by the NIR II luminogen, the\nantitumor efficiency of chemotherapeutic drugs, including paclitaxel,\ncis-platinum, and doxorubicin, was significantly enhanced. The mechanism\nexploration revealed that drug resistance-related proteins were remarkably\nreduced, making the cells more sensitive toward drugs. Thus, this\nstrategy demonstrated a promising and reliable approach to reverse\nthe drug resistance of tumor cells for efficient tumor inhibition\nin the clinic.