Tumor-penetrating nanoplatform with ultrasound "unlocking" for cascade synergistic therapy and visual feedback under hypoxia

LIFU (Low-Intensity Focused Ultrasound) Activated Tumor-Starvation/Oxidative-Stress Combined Therapy for Treating Retinoblastoma

Purpose

To overcome the limitations of traditional therapies in treating retinoblastoma, like low efficiency, systematic toxicity and poor biocompatibility.

Materials and Methods

PPFG (PLGA-PFH-Fe3O4-GOx) nanoparticles were synthesized by ultrasound double emulsification method and characterized by dynamic laser scattering, ultraviolet spectrometry, confocal laser scanning microscopy (CLSM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Phase transition by low-intensity focused ultrasound (LIFU) was observed by microscope and ultrasound imaging. Cellular uptake was compared between Y79 and HUVEC cells. ROS production was detected by 2',7'-dichlorofluorescin diacetate (DCFH-DA). Cell apoptosis was detected by flow cytometry. In vivo therapeutic effects were verified by tumor volume, HE staining, TUNEL and PCNA staining. The in vivo bio-safety was detected by serum biochemistry.

Results

PPFG NPs possesses good stability, biocompatibility and tumor-preferred uptake, with a core-shell spherical structure and an average size of 255.6nm which increases to over 100μm under LIFU irradiation. LIFU was utilized as a stimuli, by which PPFG NPs undergoes a sequential reaction starting with phase transition of PFH causing the release of the oxygen carried by PFH and GOx/SPIO carried by PPFG NPs, followed by the supplemented oxygen facilitating the enzymatic activity of glucose consumption by GOx in tumor cells (tumor starvation), the H2O2 produced during the enzymatic activity can further participate in SPIO NPs-mediated Fenton reaction (CDT), generating massive ROS. The continuously generated ROS together with the cut down of tumor nutrients by GOx effectively inhibited the progression of tumors, and synergistically enhanced ROS production together with tumor starvation promoted cell apoptosis and ultimately kills the tumour cells. No off-site injuries was detected in other major organs.

Conclusion

In this study, PPFG nanoparticles were synthesized to conduct LIFU-triggered combinational therapy on the basis of the cascade reaction among PFH, GOx and SPIO to treat retinoblastoma in vitro/vivo. It showed great potentials in combating retinoblastoma.

Intrinsic anti-inflammatory nanomedicines for enhanced pain management

Introduction

Effective postoperative pain management remains a significant challenge due to the severe side effects of opioids and the limitations of existing analgesic delivery systems. Inflammation plays a critical role in pain exacerbation, highlighting the need for therapies that combine analgesic effects with intrinsic anti-inflammatory properties.

Methods

Herein, we develop an intrinsic anti-inflammatory nanomedicine designed to enhance pain management by integrating controlled anesthetic release with inherent anti-inflammatory activity. Our nanoplatform utilizes dendritic mesoporous silica nanoparticles (MSNs) loaded with levobupivacaine and coated with Rg3-based liposomes derived from ginsenoside Rg3, termed LMSN-bupi.

Results

The MSNs enable sustained and controlled release of the local anesthetic, while the Rg3-liposome coating provides intrinsic anti-inflammatory effects by inhibiting macrophage activation. In animal models, LMSN-bupi demonstrates significantly prolonged analgesic effects and attenuated inflammatory responses compared to traditional liposome-decorated nanoparticles (TMSN-bupi) (n = 5).

Discussion

These findings underscore the potential of intrinsic anti-inflammatory nanomedicines in enhancing pain management, offering a promising strategy to overcome the limitations of current therapies and improve patient outcomes in postoperative care.

The advance of ultrasound-enabled diagnostics and therapeutics

Point-of-care ultrasound demonstrates significant potential in biomedical research due to its noninvasive, real-time visualization, cost-effectiveness, and other biological benefits. Ultrasound irradiation can precisely control the mechanical and physicochemical effects on pathogenic lesions, enabling real-time visualization, tunable tissue penetration depth, and therapeutic applications. This review summarizes recent advancements in ultrasound-enabled diagnostics and therapeutics, focusing on mechanochemical effects that can be directly integrated into biomedical applications. Additionally, the structure-functionality relationships of sonotheranostic nanoplatforms are systematically discussed, providing insights into the underlying biological effects. Finally, the limitations of current ultrasonic medicine are discussed, along with potential expansions to facilitate patient-centered translations.

Ultrasound-responsive nanocarriers with siRNA and Fe3O4 regulate macrophage polarization and phagocytosis for augmented non-small cell lung cancer immunotherapy

The immunosuppressive tumor microenvironment (TME) significantly inhibits the effective anti-tumor immune response, greatly affecting the efficacy of immunotherapy. Most tumor-associated macrophages (TAMs) belong to the M2 phenotype, which contributes significantly to the immunosuppressive effects in non-small cell lung cancer (NSCLC) TME. The interaction between signal regulatory protein α (SIRPα) expressed on macrophages and CD47, a transmembrane protein overexpressed on cancer cells, activates the "eat-me-not" signaling pathway, inhibiting phagocytosis. In this study, a folic acid (FA)-modified ultrasound responsive gene/drugs delivery system, named FA@ PFP @ Fe3O4 @LNB-SIRPα siRNA (FA-PFNB-SIRPα siRNA), was developed using 1,2-dioleoacyl-3-trimethylammonium-propane (DOTAP), FA-1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N- [amino (polyethylene glycol)2000] (DSPE-PEG2000-FA), cholesterol, and perfluoropentane (PFP), for the delivery of siRNA encoding SIRPα mRNA and immune adjuvant Fe3O4 nanoparticles. Under ultrasound conditions, the nanobubbles effectively transfected macrophages, inhibiting SIRPα mRNA and protein expression, promoting the phagocytosis of TAMs, and synergistically reversing M2 polarization. This system promotes the infiltration of T cells, enhances the proliferation and activation of cytotoxic T cells, and inhibits the infiltration of immunosuppressive cells in tumor tissues. Administration of FA-PFNB-SIRPα siRNA combined with ultrasound significantly inhibits NSCLC progression. The study highlights the potential of ultrasound nanotechnology-enabled delivery of SIRPα siRNA and Fe3O4 as an effective strategy for macrophage-based immunotherapy to reshape the immunosuppressive TME for cancer therapy.

Investigation of Ultrasound Mediated Extravasation of a Model Drug by Perfluorobutane Nanodroplets

OBJECTIVE

Perfluorocarbon nanodroplets (NDs) have been widely investigated as both diagnostic and therapeutic agents. There remains, however, a challenge in generating NDs that do not vaporize spontaneously but can be activated at ultrasound pressures that do not produce unwanted bioeffects. In previous work, it has been shown that phospholipid-coated perfluorobutane (PFB) NDs can potentially overcome this challenge. The aim of this study was to investigate whether these NDs can promote drug delivery.

METHODS

A combination of high-speed optical imaging and passive cavitation detection was used to study the acoustic properties of the PFB-NDs in a tissue mimicking phantom. PFB-NDs were exposed to ultrasound at frequencies from 0.5 to 1.5 MHz and peak negative pressures from 0.5 to 3.5 MPa. In addition, the penetration depth of two model drugs (Nile Red and 200 nm diameter fluorescent polymer spheres) into the phantom was measured.

RESULTS

PFB NDs were found to be stable in aqueous suspension at both 4°C and 37°C; their size remaining unchanged at 215 ± 11 nm over 24 h. Penetration of both model drugs in the phantom was found to increase with increasing ultrasound peak negative pressure and decreasing frequency and was found to be positively correlated with the energy of acoustic emissions. Extravasation depths >1 mm were observed at 0.5 MHz with pressures <1 MPa.

CONCLUSION

The results of the study thus suggest that PFB NDs can be used both as drug carriers and as nuclei for cavitation to enhance drug delivery without the need for high intensity ultrasound.

Consensus review on strategies to improve delivery across the blood-brain barrier including focused ultrasound

Drug delivery to the central nervous system (CNS) has been a major challenge for CNS tumors due to the impermeability of the blood-brain barrier (BBB). There has been a multitude of techniques aimed at overcoming the BBB obstacle aimed at utilizing natural transport mechanisms or bypassing the BBB which we review here. Another approach that has generated recent interest in the recently published literature is to use new technologies (Laser Interstitial Thermal Therapy, LITT; or Low-Intensity Focused Ultrasound, LIFU) to temporarily increase BBB permeability. This review overviews the advantages, disadvantages, and major advances of each method. LIFU has been a major area of research to allow for chemotherapeutics to cross the BBB which has a particular emphasis in this review. While most of the advances remain in animal studies, there are an increasing number of translational clinical trials that will have results in the next few years.

The biological roles of CD47 in ovarian cancer progression

Ovarian cancer is one of the most lethal malignant tumors, characterized by high incidence and poor prognosis. Patients relapse occurred in 65-80% after initial treatment. To date, no effective treatment has been established for these patients. Recently, CD47 has been considered as a promising immunotherapy target. In this paper, we reviewed the biological roles of CD47 in ovarian cancer and summarized the related mechanisms. For most types of cancers, the CD47/Sirpα immune checkpoint has attracted the most attention in immunotherapy. Notably, CD47 monoclonal antibodies and related molecules are promising in the immunotherapy of ovarian cancer, and further research is needed. In the future, new immunotherapy regimens targeting CD47 can be applied to the clinical treatment of ovarian cancer patients.

Interfacial engineering of Ti3C2-TiO2 MXenes by managing surface oxidation behavior for enhanced sonodynamic therapy

As a kind of reactive oxygen species (ROS) mediated therapy, sonodynamic therapy (SDT) has attracted great interest in cancer therapy. However, highly efficient and biocompatible sonosensitizers are urgently required to improve the therapeutic efficiency of SDT. In this work, Ti3C2-TiO2 MXenes were controllably synthesized as good sonosensitizers through interface engineering by regulating the dissolved oxygen concentration of the aqueous solution. The as-prepared Ar-Ti3C2-TiO2 MXene possessed a narrow band gap of 2.37 eV with promoted charge carrier transformation and efficient electron-hole separation. Compared with pure TiO2 sonosensitizers, the Ar-Ti3C2-TiO2 MXene displayed higher US-triggered reactive oxygen species (ROS) generation efficiency. In addition, the structurally maintained Ar-Ti3C2-TiO2 possessed good photothermal conversion efficiency and the laser irradiation could greatly improve the electron-hole pair separation efficiency to further increase the ROS generation capability. After modification with arginyl-glycyl-aspartic (RGD) peptide, the Ar-Ti3C2-TiO2-RGD could efficiently accumulate in the tumor sites and achieve effective PTT enhanced SDT to eliminate tumors after intravenous injection without causing appreciable long-term toxicity. Therefore, this work presented a new way to construct safe sonosensitizers for enhanced SDT and the as-prepared Ar-Ti3C2-TiO2-RGD displayed good potential for further clinical translation. STATEMENT OF SIGNIFICANCE: To achieve superior tumor treatment, the nanosized TiO2/Ti3C2 heterostructure was controllably synthesized through interface engineering by regulating the dissolved oxygen concentration of the aqueous solution using inert gas. The oxidation-optimized Ar-Ti3C2-TiO2 MXene possessed good sonodynamic performance with a narrow band gap of 2.37 eV and good photothermal conversion efficiency of 47.3% with structurally maintained Ti3C2 MXene. Additionally, the laser irradiation could greatly improve the electron-hole pair separation efficiency to further boost sonodynamic performance of Ar-Ti3C2-TiO2 MXene. Encouragingly, the Ar-Ti3C2-TiO2-RGD could efficiently accumulate in the tumor sites and achieve effective PTT enhanced SDT to eliminate tumors.

Lipid bilayer-based biological nanoplatforms for sonodynamic cancer therapy

Sonodynamic therapy (SDT) has been developed as a promising alternative therapeutic modality for cancer treatment, involving the synergetic application of sonosensitizers and low-intensity ultrasound. However, the antitumor efficacy of SDT is significantly limited due to the poor performance of conventional sonosensitizers in vivo and the constrained tumor microenvironment (TME). Recent breakthroughs in lipid bilayer-based nanovesicles (LBBNs), including multifunctional liposomes, exosomes, and isolated cellular membranes, have brought new insights into the advancement of SDT. Despite their distinct sources and preparation methods, the lipid bilayer structure in common allows them to be functionalized in many comparable ways to serve as ideal nanocarriers against challenges arising from the tumor-specific sonosensitizer delivery and the complicated TME. In this review, we provide a comprehensive summary of the recent advances in LBBN-based SDT, with particular attention on how LBBNs can be engineered to improve the delivery efficiency of sonosensitizers and overcome physical, biological, and immune barriers within the TME for enhanced sonodynamic cancer therapy. We anticipate that this review will offer valuable guidance in the construction of LBBN-based nanosonosensitizers and contribute to the development of advanced strategies for next-generation sonodynamic cancer therapy.

Cascade strategy for glucose oxidase-based synergistic cancer therapy using nanomaterials

Nanomaterial-based cancer therapy faces significant limitations due to the complex nature of the tumor microenvironment (TME). Starvation therapy is an emerging therapeutic approach that targets tumor cell metabolism using glucose oxidase (GOx). Importantly, it can provide a material or environmental foundation for other diverse therapeutic methods by manipulating the properties of the TME, such as acidity, hydrogen peroxide (H2O2) levels, and hypoxia degree. In recent years, this cascade strategy has been extensively applied in nanoplatforms for ongoing synergetic therapy and still holds undeniable potential. However, only a few review articles comprehensively elucidate the rational designs of nanoplatforms for synergetic therapeutic regimens revolving around the conception of the cascade strategy. Therefore, this review focuses on innovative cascade strategies for GOx-based synergetic therapy from representative paradigms to state-of-the-art reports to provide an instructive, comprehensive, and insightful reference for readers. Thereafter, we discuss the remaining challenges and offer a critical perspective on the further advancement of GOx-facilitated cancer treatment toward clinical translation.

Cell-Penetrating Peptide-Based Delivery of Macromolecular Drugs: Development, Strategies, and Progress

Cell-penetrating peptides (CPPs), developed for more than 30 years, are still being extensively studied due to their excellent delivery performance. Compared with other delivery vehicles, CPPs hold promise for delivering different types of drugs. Here, we review the development process of CPPs and summarize the composition and classification of the CPP-based delivery systems, cellular uptake mechanisms, influencing factors, and biological barriers. We also summarize the optimization routes of CPP-based macromolecular drug delivery from stability and targeting perspectives. Strategies for enhanced endosomal escape, which prolong its half-life in blood, improved targeting efficiency and stimuli-responsive design are comprehensively summarized for CPP-based macromolecule delivery. Finally, after concluding the clinical trials of CPP-based drug delivery systems, we extracted the necessary conditions for a successful CPP-based delivery system. This review provides the latest framework for the CPP-based delivery of macromolecular drugs and summarizes the optimized strategies to improve delivery efficiency.

The ventrolateral prefrontal cortex is part of the modular working memory system: A functional neuroanatomical perspective

For many years, the functional role of the ventrolateral Pre-Frontal Cortex (PFC) was associated with executive functions, specifically in the context of non-affective cognitive processes. However, recent research has suggested that the ventrolateral PFC is also involved in the attention system. The Ben Shalom model of the functional organization of the prefrontal cortex (2019) posits that the ventrolateral PFC selects perceptual stimuli after integration by the adjacent ventromedial PFC. This article reviews the state-of-the-art findings to better understand the role of the ventrolateral PFC in the selection of perceptual information as grounded in the Ben Shalom model. Numerous studies have reported converging evidence for the selective role of this area. However, most argue that this perceptual selection takes place through the active updating of information values linked to goal-oriented actions. These studies thus view the ventrolateral PFC as part of a system that actively manipulates and changes processed information such as the working memory function, rather than being part of the attention system. In agreement with this view, this review suggests that this area is part of a complex and modular working memory system and illustrates with reference to Diamond's work on ADD. This working memory system is functionally and anatomically dispersed and includes the dorsolateral PFC, the ACC, the parietal cortex, the basal ganglia, and the cerebellum. Hence, future research should continue to explore the specific neurofunctional roles of these areas in working memory systems, and the connections between the different subareas in this complex array.