Recent near-infrared light-activated nanomedicine toward precision cancer therapy

Carbon Dots in Photodynamic/Photothermal Antimicrobial Therapy

Antimicrobial resistance (AMR) presents an escalating global challenge as conventional antibiotic treatments become less effective. In response, photodynamic therapy (PDT) and photothermal therapy (PTT) have emerged as promising alternatives. While rooted in ancient practices, these methods have evolved with modern innovations, particularly through the integration of lasers, refining their efficacy. PDT harnesses photosensitizers to generate reactive oxygen species (ROS), which are detrimental to microbial cells, whereas PTT relies on heat to induce cellular damage. The key to their effectiveness lies in the utilization of photosensitizers, especially when integrated into nano- or micron-scale supports, which amplify ROS production and enhance antimicrobial activity. Over the last decade, carbon dots (CDs) have emerged as a highly promising nanomaterial, attracting increasing attention owing to their distinctive properties and versatile applications, including PDT and PTT. They can not only function as photosensitizers, but also synergistically combine with other photosensitizers to enhance overall efficacy. This review explores the recent advancements in CDs, underscoring their significance and potential in reshaping advanced antimicrobial therapeutics.

Advances of Layered Double Hydroxide-Based Materials for Tumor Imaging and Therapy

Layered double hydroxides (LDH) are a class of functional anionic clays that typically consist of orthorhombic arrays of metal hydroxides with anions sandwiched between the layers. Due to their unique properties, including high chemical stability, good biocompatibility, controlled drug loading, and enhanced drug bioavailability, LDHs have many potential applications in the medical field. Especially in the fields of bioimaging and tumor therapy. This paper reviews the research progress of LDHs and their nanocomposites in the field of tumor imaging and therapy. First, the structure and advantages of LDH are discussed. Then, several commonly used methods for the preparation of LDH are presented, including co-precipitation, hydrothermal and ion exchange methods. Subsequently, recent advances in layered hydroxides and their nanocomposites for cancer imaging and therapy are highlighted. Finally, based on current research, we summaries the prospects and challenges of layered hydroxides and nanocomposites for cancer diagnosis and therapy.

A Bioorthogonal Antidote Against the Photosensitivity after Photodynamic Therapy

As an effective and non-invasive treatment modality for cancer, photodynamic therapy (PDT) has attracted considerable interest. With the recent advances in the photosensitizing agents, the fiber-optic systems, and other aspects, its application is extended to a wide range of superficial and localized cancers. However, for the few clinically used photosensitizers, most of them suffer from the drawback of causing prolonged photosensitivity after the treatment. As a result, post-PDT management is also a crucial issue. Herein, a facile bioorthogonal approach is reported that can effectively suppress this common side effect of PDT in nude mice. It involves the use of an antidote that contains a black-hole quencher BHQ-3 conjugated with a bicyclo[6.1.0]non-4-yne (BCN) moiety and a tetrazine-substituted boron dipyrromethene-based photosensitizer. By using tumor-bearing nude mice as an animal model, it is demonstrated that after PDT with this photosensitizer, the administration of the antidote can effectively quench the photodynamic activity of the residual photosensitizer by bringing the BHQ-3 quencher close to the photosensitizing unit through a rapid click reaction. It results in substantial reduction in skin damage upon light irradiation. The overall results demonstrate that this simple and facile strategy can provide an effective means for minimizing the photosensitivity after PDT.

Recent Advances in Organometallic NIR Iridium(III) Complexes for Detection and Therapy

Iridium(III) complexes are emerging as a promising tool in the area of detection and therapy due to their prominent photophysical properties, including higher photostability, tunable phosphorescence emission, long-lasting phosphorescence, and high quantum yields. In recent years, much effort has been devoted to develop novel near-infrared (NIR) iridium(III) complexes to improve signal-to-noise ratio and enhance tissue penetration. In this review, we summarize different classes of organometallic NIR iridium(III) complexes for detection and therapy, including cyclometalated ligand-enabled NIR iridium(III) complexes and NIR-dye-conjugated iridium(III) complexes. Moreover, the prospects and challenges for organometallic NIR iridium(III) complexes for targeted detection and therapy are discussed.

Bioorthogonally Assisted Phototherapy: Recent Advances and Prospects

Photoresponsive materials offer excellent spatiotemporal control over biological processes and the emerging phototherapeutic methods are expected to have significant effects on targeted cancer therapies. Recent examples show that combination of photoactivatable approaches with bioorthogonal chemistry enhances the precision of targeted phototherapies and profound implications are foreseen particularly in the treatment of disperse/diffuse tumors. The extra level of on-target selectivity and improved spatial/temporal control considerably intensified related bioorthogonally assisted phototherapy research. The anticipated growth of further developments in the field justifies the timeliness of a brief summary of the state of the art.

Light-responsive nanomedicine for cancer immunotherapy

Immunotherapy emerged as a paradigm shift in cancer treatments, which can effectively inhibit cancer progression by activating the immune system. Remarkable clinical outcomes have been achieved through recent advances in cancer immunotherapy, including checkpoint blockades, adoptive cellular therapy, cancer vaccine, and tumor microenvironment modulation. However, extending the application of immunotherapy in cancer patients has been limited by the low response rate and side effects such as autoimmune toxicities. With great progress being made in nanotechnology, nanomedicine has been exploited to overcome biological barriers for drug delivery. Given the spatiotemporal control, light-responsive nanomedicine is of great interest in designing precise modality for cancer immunotherapy. Herein, we summarized current research utilizing light-responsive nanoplatforms to enhance checkpoint blockade immunotherapy, facilitate targeted delivery of cancer vaccines, activate immune cell functions, and modulate tumor microenvironment. The clinical translation potential of those designs is highlighted and challenges for the next breakthrough in cancer immunotherapy are discussed.

In-Tumor Biosynthetic Construction of Upconversion Nanomachines for Precise Near-Infrared Phototherapy

Targeted construction of therapeutic nanoplatforms in tumor cells with specific activation remains appealing but challenging. Here, we design a cancer-motivated upconversion nanomachine (UCNM) based on porous upconversion nanoparticles (p-UCNPs) for precise phototherapy. The nanosystem is equipped with a telomerase substrate (TS) primer and simultaneously encapsulates 5-aminolevulinic acid (5-ALA) and d-arginine (d-Arg). After coating with hyaluronic acid (HA), it can readily get into tumor cells, where 5-ALA induces efficient accumulation of protoporphyrin IX (PpIX) via the inherent biosynthetic pathway, and the overexpressed telomerase prolonged the TS to form G-quadruplexes (G4) for binding the resulting PpIX as a nanomachine. This nanomachine can respond to near-infrared (NIR) light and promote the active singlet oxygen (¹O₂) production due to the efficiency of Förster resonance energy transfer (FRET) between p-UCNPs and PpIX. Intriguingly, such oxidative stress can oxidize d-Arg into nitric oxide (NO), which relieves the tumor hypoxia and in turn improves the phototherapy effect. This in situ assembly approach significantly enhances targeting in cancer therapy and might be of considerable clinical value.

New insight into brain disease therapy: nanomedicines-crossing blood-brain barrier and extracellular space for drug delivery

INTRODUCTION

Brain diseases including brain tumor, Alzheimer's disease, Parkinson's disease, etc. are difficult to treat. The blood-brain barrier (BBB) is a major obstacle for drug delivery into the brain. Although nano-package and receptor-mediated delivery of nanomedicine markedly increases BBB penetration, it yet did not extensively improve clinical cure rate. Recently, brain extracellular space (ECS) and interstitial fluid (ISF) drainage in ECS have been found to determine whether a drug dissolved in ISF can reach its target cells. Notably, an increase in tortuosity of ECS associated with slower ISF drainage induced by the accumulated harmful substances, such as: amyloid-beta (Aβ), α-synuclein, and metabolic wastes, causes drug delivery failure.

AREAS COVERED

The methods of nano-package and receptor-mediated drug delivery and the penetration efficacy of nanomedicines across BBB and ECS are assessed.

EXPERT OPINION

Invasive delivering drug via ECS and noninvasive near-infrared photo-sensitive nanomedicines may provide a promising benefit to patients with brain disease.

Red blood cell membrane nanoparticles for tumor phototherapy

Non-invasive phototherapy includes photodynamic therapy (PDT) and photothermal therapy (PTT), and has garnered special interest in anti-tumor therapy. However, traditional photosensitizers or photothermal agents are faced with major challenges, including easy recognition by immune system, rapid clearance from blood circulation, and low accumulation in target sites. Combining the characteristics of natural cell membrane with the characteristics of photosensitizer or photothermal agent is an important technology to achieve the ideal therapeutic effect of cancer. Red cell membrane (RBMs) coated can disguise phototherapy agents as endogenous substances, thus constructing a new nano bionic therapeutic platform, resisting blood clearance and prolonging circulation time. At present, a variety of phototherapy agents based on Nano-RBMs have been isolated or designed. In this review, firstly, the basic principles of Nano-RBMs and phototherapy are expounded respectively. Then, the latest progress of Nano-RBMs for PDT, PTT and PDT/PTT applications in recent five years has been introduced respectively. Finally, the problems and challenges of Nano-RBMs in the field of phototherapy are put forward.

A Nanomedicine Structure-Activity Framework for Research, Development, and Regulation of Future Cancer Therapies

Despite their clinical success in drug delivery applications, the potential of theranostic nanomedicines is hampered by mechanistic uncertainty and a lack of science-informed regulatory guidance. Both the therapeutic efficacy and the toxicity of nanoformulations are tightly controlled by the complex interplay of the nanoparticle's physicochemical properties and the individual patient/tumor biology; however, it can be difficult to correlate such information with observed outcomes. Additionally, as nanomedicine research attempts to gradually move away from large-scale animal testing, the need for computer-assisted solutions for evaluation will increase. Such models will depend on a clear understanding of structure-activity relationships. This review provides a comprehensive overview of the field of cancer nanomedicine and provides a knowledge framework and foundational interaction maps that can facilitate future research, assessments, and regulation. By forming three complementary maps profiling nanobio interactions and pathways at different levels of biological complexity, a clear picture of a nanoparticle's journey through the body and the therapeutic and adverse consequences of each potential interaction are presented.

Bioorthogonal Click of Colloidal Gold Nanoparticles to Antibodies In vivo

Combining nanotechnology and bioorthogonal chemistry for theranostic strategies offers the possibility to develop next generation nanomedicines. These materials are thought to increase therapeutic outcome and improve current cancer management. Due to their size, nanomedicines target tumors passively. Thus, they can be used for drug delivery purposes. Bioorthogonal chemistry allows for a pretargeting approach. Higher target-to-background drug accumulation ratios can be achieved. Pretargeting can also be used to induce internalization processes or trigger controlled drug release. Colloidal gold nanoparticles (AuNPs) have attracted widespread interest as drug delivery vectors within the last decades. Here, we demonstrate for the first time the possibility to successfully ligate AuNPs in vivo to pretargeted monoclonal antibodies. We believe that this possibility will facilitate the development of AuNPs for clinical use and ultimately, improve state-of-the-art patient care.

Tumor-microenvironment activated duplex genome-editing nanoprodrug for sensitized near-infrared titania phototherapy

Near-infrared (NIR)-light-triggered nanomedicine, including photodynamic therapy (PDT) and photothermal therapy (PTT), is growing an attractive approach for cancer therapy due to its high spatiotemporal controllability and minimal invasion, but the tumor eradication is limited by the intrinsic anti-stress response of tumor cells. Herein, we fabricate a tumor-microenvironment responsive CRISPR nanoplatform based on oxygen-deficient titania (TiO2-x ) for mild NIR-phototherapy. In tumor microenvironment, the overexpressed hyaluronidase (HAase) and glutathione (GSH) can readily destroy hyaluronic acid (HA) and disulfide bond and releases the Cas9/sgRNA from TiO2-x to target the stress alleviating regulators, i.e., nuclear factor E2-related factor 2 (NRF2) and heat shock protein 90α (HSP90α), thereby reducing the stress tolerance of tumor cells. Under subsequent NIR light illumination, the TiO2-x demonstrates a higher anticancer effect both in vitro and in vivo. This strategy not only provides a promising modality to kills cancer cells in a minimal side-effects manner by interrupting anti-stress pathways but also proposes a general approach to achieve controllable gene editing in tumor region without unwanted genetic mutation in normal environments.

Stimuli-Responsive Gold Nanocages for Cancer Diagnosis and Treatment

With advances in nanotechnology, various new drug delivery systems (DDSs) have emerged and played a key role in the diagnosis and treatment of cancers. Over the last two decades, gold nanocages (AuNCs) have been attracting considerable attention because of their outstanding properties. This review summarizes current advancements in endogenous, exogenous, and dual/multi-stimuli responsive AuNCs in drug delivery. This review focuses on the properties, clinical translation potential, and limitations of stimuli-responsive AuNCs for cancer diagnosis and treatment.

Molecular Switches—Tools for Imparting Control in Drug Delivery Systems

Cancer is a globally prevalent cause of premature mortality. Of growing interest is the development of novel anticancer therapies and the optimisation of associated risks. Major issues presently facing conventional anticancer therapies include systemic toxicity, poor solubility, membrane permeability, and multidrug resistance Nanocarriers have been employed to address these issues. Nanocarriers encapsulate anticancer drugs, enabling them to bypass biological barriers and minimise their adverse side effects. These drug delivery systems offer extensive benefits as they can be modified to gravitate towards specific environmental conditions. To further enhance the safety and efficacy of these drug carriers, modern developments have included incorporating a molecular switching mechanism into their structure. These molecular switches are responsive to endogenous and exogenous stimuli and may undergo reversible and repeatable conformational changes when activated. The incorporation of molecular switches can, therefore, impart stimuli-responsive drug-release control on a DDS. These stimuli can then be manipulated to offer precise dosage control over the drug release at a specific target site. This review discusses recent developments in the design of DDSs incorporating light and pH-responsive molecular switches as drug release controllers.