Chemical chaperone delivered nanoscale metal–organic frameworks as inhibitor of endoplasmic reticulum for enhanced sensitization of thermo-chemo therapy

Thermotherapy and chemotherapy have received extensive attention to tumor treatment. However, thermal tolerance and drug resistance severely limit clinical effect of tumor therapy owing to endoplasmic reticulum (ER) stress. Reducing thermal tolerance and drug resistance of tumors is an urgent challenge to be solved. In this work, we design a nanoplatform of PBA-Dtxl@MIL-101 as an ER inhibitor. Amino functionalized Fe-metal organic framework (MIL-101) nanoparticles are synthesized as pH and microwave (MW) dual stimuli-responsive drug delivery system. Then, the chemical chaperones of 4-phenylbutyric acid (PBA) and antineoplastic drug Docetaxel (Dtxl) were successfully loaded into MIL-101 nanoparticles to form PBA-Dtxl@MIL-101 nanoparticles. Furthermore, PBA-Dtxl@MIL-101 nanoparticles exhibit inhibitor effect of ER stress through upregulating caspase 9 proteins and reduce thermal tolerance by downregulating HSP 90. It was demonstrated that the therapy sensitized by PBA-Dtxl@MIL-101 nanoparticles obviously destroyed tumor cells, showing simultaneously enhanced thermo-chemo therapy.