Zn2+-interference and H2S-mediated gas therapy based on ZnS-tannic acid nanoparticles synergistic enhancement of cell apoptosis for specific treatment of prostate cancer.

ABSTRACT

Zn2+ and H2S are essential to maintain normal prostate function, and sometimes can evolve into weapons to attack and destroy prostate cancer (PCa) cells. Nevertheless, how to achieve the targeted and effective release of Zn2+ and H2S, and reverse the concentration distribution within PCa tumor cells still highly challenging. Herein, combined with these pathological characteristics of prostate, we proposed a tumor microenvironment (TME) responsive Zn2+-interference and H2S-mediated gas synergistic therapy strategy based on a nanoplatform of tannic acid (TA) modified zinc sulfide nanoparticles (ZnS@TA) for the specific treatment of PCa. Once the constructed pH-responsive ZnS@TA internalized by cancer cells, it would instantaneously decomposed in acidic TME, and explosively release excess Zn2+ and H2S exceeding the cell self-regulation threshold. Meanwhile, the in situ produced Zn2+ and H2S synergistic enhancement of cell apoptosis, which is evidenced to increase levels of Bax and Bax/Bcl-2 ratio, release of Cytochrome c in cancer cells, contributing to inhibit the growth of tumor. Moreover, the TA in cooperation with Zn2+ specifically limits the migration and invasion of PCa cells. Both in vitro and in vivo results demonstrate that the Zn2+-interference in combination with H2S-mediated gas therapy achieves an excellent anti-tumor performance. Overall, this nanotheranostic synergistic therapy provides a promising direction for exploring new strategies for cancer treatment based on specific tumor pathological characteristics, and provides a new vision for promoting practical cancer therapy.