Bioengineered "Molecular Glue"-Mediated Tumor-Specific Cascade Nanoreactors with Self-Destruction Ability for Enhanced Precise Starvation/Chemosynergistic Tumor Therapy

Nanomaterials in cancer starvation therapy: pioneering advances, therapeutic potential, and clinical challenges

Gaining significant attention in recent years, starvation therapy based on the blocking nutrients supply to cancer cells via blood occlusion and metabolic interventions is a promisingly novel approach in cancer treatment. However, there are many crucial obstacles to overcome to achieve effective treatment, for example, poor-targeting delivery, cellular hypoxia, adverse effects, and ineffective monotherapy. The starvation-based multitherapy based on multifunctional nanomaterials can narrow these gaps and pave a promising way for future clinical translation. This review focuses on the progression in nanomaterials-mediated muti-therapeutic modalities based on starvation therapy in recent years and therapeutic limitations that prevent their clinical applications. Moreover, unlike previous reviews that focused on a single aspect of the field, this comprehensive review presents a broader perspective on starvation therapy by summarising advancements across its various therapeutic strategies.

Emerging glucose oxidase-delivering nanomedicines for enhanced tumor therapy

Abnormalities in glucose metabolism have been shown to characterize malignant tumors. Glucose depletion by glucose oxidase (GOD) has shown great potential in tumor therapy by causing tumor starvation. Since 2017, nanomedicines have been designed and utilized to deliver GOD for more precise and effective glucose modulation, which can overcome intrinsic limitations of different cancer therapeutic modalities by remodeling the tumor microenvironment to enhance antitumor therapy. To date, the topic of GOD-delivering nanomedicines for enhancing tumor therapy has not been comprehensively summarized. Herein, this review aims to provide an overview and discuss in detail recent advances in GOD delivery and directly involved starvation therapy strategies, GOD-sensitized various tumor therapy strategies, and GOD-mediated multimodal antitumor strategies. Finally, the challenges and outlooks for the future progress of the emerging tumor therapeutic nanomedicines are discussed. This review provides intuitive and specific insights to a broad audience in the fields of nanomedicines, biomaterials, and cancer therapy.

Cascade-Catalyzed Nanogel for Amplifying Starvation Therapy by Nitric Oxide-Mediated Hypoxia Alleviation

Glucose oxidase (Gox)-mediated starvation therapy offers a prospective advantage for malignancy treatment by interrupting the glucose supply to neoplastic cells. However, the negative charge of the Gox surface hinders its enrichment in tumor tissues. Furthermore, Gox-mediated starvation therapy infiltrates large amounts of hydrogen peroxide (H2O2) to surround normal tissues and exacerbate intracellular hypoxia. In this study, a cascade-catalyzed nanogel (A-NE) was developed to boost the antitumor effects of starvation therapy by glucose consumption and cascade reactive release of nitric oxide (NO) to relieve hypoxia. First, the surface cross-linking structure of A-NE can serve as a bioimmobilization for Gox, ensuring Gox stability while improving the encapsulation efficiency. Then, Gox-mediated starvation therapy efficiently inhibited the proliferation of tumor cells while generating large amounts of H2O2. In addition, covalent l-arginine (l-Arg) in A-NE consumed H2O2 derived from glucose decomposition to generate NO, which augmented starvation therapy on metastatic tumors by alleviating tumor hypoxia. Eventually, both in vivo and in vitro studies indicated that nanogels remarkably inhibited in situ tumor growth and hindered metastatic tumor recurrence, offering an alternative possibility for clinical intervention.

Sorafenib-Encapsulated Liposomes to Activate Hypoxia-Sensitive Tirapazamine for Synergistic Chemotherapy of Hepatocellular Carcinoma

Combination therapy with the synergistic effect is an effective way in cancer chemotherapy. Herein, an antiangiogenic sorafenib (SOR) and hypoxia-activated prodrug tirapazamine (TPZ)-coencapsulated liposome (LipTPZ/SOR) is prepared for chemotherapy of hepatocellular carcinoma (HCC). SOR is a multi-target tyrosine kinase inhibitor that can inhibit tumor cell proliferation and angiogenesis. The antiangiogenesis effect of SOR can reduce oxygen supply and aggravate tumor hypoxia, which is able to activate hypoxia-sensitive prodrug TPZ, exhibiting the synergistic antitumor effect. LipTPZ/SOR at different molar ratios of TPZ and SOR can significantly inhibit the proliferation of hepatocellular carcinoma cells. The mole ratio of TPZ and SOR was optimized to 2:1, which exhibited the best synergetic antitumor effect. The synergistic antitumor mechanism of SOR and TPZ was also investigated in vivo. After treated with SOR, the number of vessels was decreased, and the degree of hypoxia was aggravated in tumor tissues. What is more, in the presence of SOR, TPZ could be activated to inhibit tumor growth. The combination of TPZ and SOR exhibited an excellent synergistic antitumor effect. This research not only provides an innovative strategy to aggravate tumor hypoxia to promote TPZ activation but also paints a blueprint about a new nanochemotherapy regimen for the synergistic chemotherapy of HCC, which has excellent biosafety and bright clinical application prospects.

Silicon-containing nanomedicine and biomaterials: materials chemistry, multi-dimensional design, and biomedical application

The invention of silica-based bioactive glass in the late 1960s has sparked significant interest in exploring a wide range of silicon-containing biomaterials from the macroscale to the nanoscale. Over the past few decades, these biomaterials have been extensively explored for their potential in diverse biomedical applications, considering their remarkable bioactivity, excellent biocompatibility, facile surface functionalization, controllable synthesis, etc. However, to expedite the clinical translation and the unexpected utilization of silicon-composed nanomedicine and biomaterials, it is highly desirable to achieve a thorough comprehension of their characteristics and biological effects from an overall perspective. In this review, we provide a comprehensive discussion on the state-of-the-art progress of silicon-composed biomaterials, including their classification, characteristics, fabrication methods, and versatile biomedical applications. Additionally, we highlight the multi-dimensional design of both pure and hybrid silicon-composed nanomedicine and biomaterials and their intrinsic biological effects and interactions with biological systems. Their extensive biomedical applications span from drug delivery and bioimaging to therapeutic interventions and regenerative medicine, showcasing the significance of their rational design and fabrication to meet specific requirements and optimize their theranostic performance. Additionally, we offer insights into the future prospects and potential challenges regarding silicon-composed nanomedicine and biomaterials. By shedding light on these exciting research advances, we aspire to foster further progress in the biomedical field and drive the development of innovative silicon-composed nanomedicine and biomaterials with transformative applications in biomedicine.