Targeted delivery and accumulation of chemotherapeutics to tumor sites is in high demand and extremely challenging for anticancer therapy. Studies show that albumin is actively recruited into tumor tissue overexpressing albumin-binding proteins including secreted protein acidic and rich in cysteine (SPARC) and gp60. Herein, a novel redox-responsive paclitaxel-loaded micelle system with the modification of ABD035, which specifically and strongly binds to albumin, is designed to combine the strengths of albumin and micelles together for antitumor drug biomimetic delivery. The ABD035-modified micelle has a strong binding response to albumin and co-localization of BODIPY-labeled ABD035-modified micelle and SPARC is observed in tumor tissues. Furthermore, the ABD035-modified micelle significantly improves the therapeutic effect in the animal model bearing triple negative breast cancer by increasing drug accumulation in tumor tissue, enhancing cell uptake efficiency, rapidly releasing prototype drug under intracellular reductive conditions and increasing tumor cell apoptosis. These results together vote the biomimetic delivery of ABD035-modified micelle as a promising strategy for cancer therapy.
Wen Kang,Yuyuan Shi,Zhenlu Yang,Xindao Yin,Ying Zhao,Lixing Weng,Zhaogang Teng
As a non-invasive cancer treatment, photodynamic therapy (PDT) has great applications in superficial tumors because of its high selectivity and low cumulative toxicity. However, the poor tumor-targeting ability and short blood circulation time of conventional photosensitizers (PSs) limit the efficacy of PDT to some extent. In this study, we synthesized flexible hollow human serum albumin (HHSA) and loaded photosensitizer Chlorin e6 (Ce6) and the chemotherapeutic drug Doxorubicin (DOX) for synergistic cancer therapy. HHSA can enhance drug delivery and cellular uptake through targeting gp60 and SPARC receptors and unique flexible hollow structures. The TEM images show that HHSA possesses distinct flexible hollow structures, as well as good monodispersity and deformability. After loading Ce6 and DOX, HHSA@Ce6-DOX displays better therapeutic effects than HHSA@DOX on the growth of 4T1 breast cancers without irradiation. Remarkably, it has a significantly higher therapeutic effect (relative cell activity: 45% vs. 74%) than HHSA@Ce6 under 660 nm irradiation. Furthermore, the excellent biocompatibility of HHSA@Ce6-DOX has been proved both in vitro and in vivo, indicating that it has a promising future in synergistic tumor treatments.
Immunosuppressive microenvironment and poor immunogenicity are two stumbling blocks in anti-tumor immune activation. Tumor associated macrophages (TAMs) play crucial roles in immunosuppressive microenvironment, while immunogenic cell death (ICD) is a typical strategy to boost immunogenicity. Herein, we developed a coordinative modular assembly-based self-reinforced nanoparticle, (CaO 2 /TA)-(Fe 3+ /BSA) which integrated CaO 2 , Fe 3+ -tannic acid coordinated networks and albumin under the instruction of molecular dynamics simulation. (CaO 2 /TA)-(Fe 3+ /BSA) could significantly enhance Fenton reaction through Fe 3+ self-reduction and H 2 O 2 self-sufficiency, and simultaneously increased intracellular accumulation of Ca 2+ . The self-augmented Fenton reaction with sufficient reactive oxygen species effectively repolarized TAMs and elicited ICD with Ca 2+ overload. Besides, (CaO 2 /TA)-(Fe 3+ /BSA) was confirmed to self-reinforce deep tumor drug delivery by “treatment-delivery” positive feedback based on gp60-mediated transcytosis and M2-like macrophages repolarization-mediated perfusion promotion. Resultantly, (CaO 2 /TA)-(Fe 3+ /BSA) effectively alleviated immunosuppression, provoked local and systemic immune response and potentiated anti-PD-1 antibody therapy. Our strategy highlights a facile and controllable approach to construct penetrated effective antitumor nano-immunotherapeutic agent.