Background: Although cisplatin-based chemotherapy has been used as the first-line treatment for ovarian cancer (OC), tumor cells develop resistance to cisplatin during treatment, causing poor prognosis in OC patients. Studies have demonstrated that overactivation of the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway is involved in tumor chemoresistance and that overexpression of microRNA-497 (miR497) may overcome OC chemotherapy resistance by inhibiting the mTOR pathway. However, the low transcriptional efficiency and unstable chemical properties of miR497 limit its clinical application. Additionally, triptolide (TP) was confirmed to possess a superior killing effect on cisplatin-resistant cell lines, partially through inhibiting the mTOR pathway. Even so, the clinical applications of TP are restricted by serious systemic toxicity and weak water solubility.Results: Herein, whether the combined application of miR497 and TP could further overcome OC chemoresistance by synergically suppressing the mTOR signaling pathway was investigated. Bioinspired hybrid nanoparticles formed by the fusion of CD47-expressing tumor exosomes and cRGD-modified liposomes (miR497/TP-HENPs) were prepared to codeliver miR497 and TP. In vitro results indicated that the nanoparticles were efficiently taken up by tumor cells, thus significantly enhancing tumor cell apoptosis. Similarly, the hybrid nanoparticles were effectively enriched in the tumor areas and exerted significant anticancer activity without any negative effects in vivo. Mechanistically, they promoted dephosphorylation of the overactivated PI3K/AKT/mTOR signaling pathway, boosted reactive oxygen species (ROS) generation and upregulated the polarization of macrophages from M2 to M1 macrophages.Conclusion: Overall, our findings may provide a translational strategy to overcome cisplatin-resistant OC and offer a potential solution for the treatment of other cisplatin-resistant tumors.Graphical

Advanced liver cancer is the most fatal malignant cancer, and the clinical outcomes of treatment are not very satisfactory due to the complexity and heterogeneity of the tumor. Combination therapy can efficiently enhance tumor treatment by stimulating multiple pathways and regulating the tumor immune microenvironment. Nanodrug delivery systems have become attractive candidates for combined strategies for liver cancer treatment. This study reports a nano ultrasound contrast agent (arsenic trioxide (ATO)/PFH NPs@Au‐cRGD) to integrate diagnosis and treatment for efficient ultrasound imaging and liver cancer therapy. This nanodrug delivery system promotes tumor‐associated antigens release through ATO‐induced ferroptosis and photothermal‐induced immunogenic cell death, enhancing the synergistic effects of ATO and photothermal therapy in human Huh7 and mouse Hepa1–6 cells. This drug delivery system successfully activates the antitumor immune response and promotes macrophage M1 polarization in tumor microenvironment with low side effects in subcutaneous and orthotopic liver cancer. Furthermore, tumor metastasis is inhibited and long‐term immunological memory is also established in orthotopic liver cancer when the nanodrug delivery system is combined with anti‐programmed death‐ligand 1 (PD‐L1) immunotherapy. This safe nanodrug delivery system can enhance antitumor therapy, inhibit lung metastasis, and achieve visual assessment of therapeutic efficacy, providing substantial potential in clinic applications for liver cancer.