Multidrug resistance (MDR) is a key issue accounting for ineffectiveness of cancer chemotherapy. Numerous multifunctional nanocarriers have been developed to increase drug delivery efficacy and inhibit drug efflux for overcoming cancer drug resistance. However, limited success has been achieved in clinic because of nanocarriers' complicated multi-step fabrication procedures and their undesired side toxicity as well as potential immunogenicity . Here, hyaluronic acid (HA) functionalized extracellular vesicles (EVs) are generated as natural vehicles to efficiently deliver doxorubicin (DOX) and reverse MDR. The EVs isolated from noncancerous HEK293T cells (hEVs) reduce P-glycoprotein (P-gp) expression in drug resistant MCF7/ADR cells. To acquire tumor-targeting capability, hEVs are modified with lipidomimetic chains-grafted HA (lipHA) by a simple incubation. Owing to CD44-mediated cancer-specific targeting and P-gp suppressive capability, the HA-functionalized hEVs (lipHA-hEVs) remarkably promote the intracellular DOX accumulation in drug resistant breast cancer cells. In preclinical MDR tumor models, lipHA-hEVs deeply penetrate into tumor tissue and effectively transport DOX into tumor local, while eliminating DOX's systemic toxicity. Importantly, [email protected] inhibited MDR tumor growth by 89% and extend animal survival time by approximately 50%. Thus, our engineered tumor-targeting hEVs are promising natural carriers for overcoming cancer MDR.
Multidrug resistance (MDR), as a major obstacle in cancer therapy, has resulted in over 90% of cancer chemotherapeutic failure. Mesoporous silica nanospheres (MSNs) have been demonstrated to be tuned with large pore sizes, mediating the MDR-reversal effects. However, the study that surface functionality of the large pore sized-MSNs affects the MDR-overcoming effects hasn’t been extensively studied. In this study, we developed a new dendrimer-like MSNs delivery system based on a rational synthesis strategy and further modified MSNs with various surface functionalities to evaluate their roles in overcoming cancer MDR. Our results showed that the small particle sized-MSNs could be fabricated with dendrimer-like internal structure, resulting in the large pore size of 9 nm. Surface functionality of MSNs, especially hydroxylation and carboxylation, largely improved the intra-nuclear delivery and therapeutic efficiency of DOX for MCF7/ADR cells, which was not up to inhibiting P-gp expression but significantly increasing the intracellular drug accumulation of over 90% even under the strong drug efflux. This study indicates that surface functionality design strategy may display the potential of the large pore sized-MSNs as the efficient chemotherapeutic carriers to combat MDR.
危险品化学品经营许可证（带存储）