Rationally designed rapamycin-encapsulated ZIF-8 nanosystem for overcoming chemotherapy resistance

作者：Xu, Mengran; Hu, Yi; Ding, Weiping; Li, Fenfen; Lin, Jun; Wu, Min; Wu, Jingjing; Wen, Long-Ping^*; Qiu, Bensheng^*; Wei, Peng-Fei^*; Li, Ping^*

来源：Biomaterials, 2020, 258: 120308.

DOI：10.1016/j.biomaterials.2020.120308

• Zeolitic imidazolate Framework-8 (ZIF-8)
• Pro-death autophagy
• Overcoming drug resistance
• Mammalian target of rapamycin (mTOR)
• Doxorubicin

Zeolitic imidazolate framework-8 (ZIF-8) nanoparticles are widely reported as a pH-sensitive drug delivery carrier with high loading capacity for tumor therapy. However, the mechanism of intracellular corrosion of ZIF-8 and the corresponding biological effects especially for autophagy response have been rarely reported. Herein, the as-synthesized ZIF-8 was demonstrated to induce mTOR independent and pro-death autophagy. Interestingly, the autophagic process participated in the corrosion of ZIF-8. Subsequently, zinc ion release and the generation of reactive oxygen species due to its corrosion in the acidic compartments were directly responsible for tumor cell killing. In addition, ZIF-8 could sensitize tumor cells to chemotherapy by switching cytoprotective to death promoting autophagy induced by doxorubicin. The mTOR signaling pathway activation was demonstrated to restrict tumor chemotherapy efficiency. Hence, a combined platform rapamycin encapsulated zeolitic imidazolate frameworks (Rapa@ZIF-8) was constructed and demonstrated a more significant chemo-sensitized effect relative to ZIF-8 nanoparticles or rapamycin treatment alone. Lastly, the combined administration of Rapa@ZIF-8 and doxorubicin exhibited an outstanding synergistic antitumor effect without any obvious toxicity to the major organs of mice. Collectively, the optimized nanoplatform, Rapa@ZIF-8, provides a proof of concept for intentionally interfering mTOR pathway and utilizing the switch of survival-to death-promoting autophagy for adjunct chemotherapy.

• 单位
  安徽医科大学; 1