Advances in Atherosclerosis Theranostics Harnessing Iron Oxide-Based Nanoparticles

Atherosclerosis, a multifaceted chronic inflammatory disease, has a profound impact on cardiovascular health. However, the critical limitations of atherosclerosis management include the delayed detection of advanced stages, the intricate assessment of plaque stability, and the absence of efficacious therapeutic strategies. Nanotheranostic based on nanotechnology offers a novel paradigm for addressing these challenges by amalgamating advanced imaging capabilities with targeted therapeutic interventions. Meanwhile, iron oxide nanoparticles have emerged as compelling candidates for theranostic applications in atherosclerosis due to their magnetic resonance imaging capability and biosafety. This review delineates the current state and prospects of iron oxide nanoparticle-based nanotheranostics in the realm of atherosclerosis, including pivotal aspects of atherosclerosis development, the pertinent targeting strategies involved in disease pathogenesis, and the diagnostic and therapeutic roles of iron oxide nanoparticles. Furthermore, this review provides a comprehensive overview of theranostic nanomedicine approaches employing iron oxide nanoparticles, encompassing chemical therapy, physical stimulation therapy, and biological therapy. Finally, this review proposes and discusses the challenges and prospects associated with translating these innovative strategies into clinically viable anti-atherosclerosis interventions. In conclusion, this review offers new insights into the future of atherosclerosis theranostic, showcasing the remarkable potential of iron oxide-based nanoparticles as versatile tools in the battle against atherosclerosis.

PDT-active upconversion nanoheaters for targeted imaging guided combinatorial cancer phototherapies with low-power single NIR excitation

A versatile nanoformulation is designed by anchoring human transferrin protein (Tf) on fluoromagnetic upconverting nanoheaters, NaGdF₄:Yb,Er (UCNP), loaded with Rose Bengal (RB), for multimodal imaging guided synergistic photothermal (PTT) and photodynamic therapy (PDT) at the targeted tumor site. The NIR excitation of the UCNP-RB Forster Resonance Energy Transfer (FRET) pair results in the reactive oxygen species (ROS) generation for PDT, whereas the non-radiative transitions in Er result in the heat required for PTT. The intravenously injected theranostic agent (UCNP@Tf-RB) enabled; (1) combinatorial PTT and PDT of 4T1 tumors with minimal systemic toxicity, (2) dual targeted (passive and active) tumor accumulation, (3) dual-modal imaging (MRI/photothermal), and, (4) excellent stability and biocompatibility. The in vitro therapy data corroborates the MRI findings that Tf conjugation resulted in actively targeted tumor accumulation via over-expressed transferrin receptors (TfR) on 4T1 cells. Real-time photothermal imaging enabled visualization of the tumor while receiving the therapy. The UCNP@Tf-RB, for synergistic PTT-PDT, and UCNP@Tf, for PTT only, caused rapid suppression of tumor with a tumor-growth inhibition index (TGII) of ~0.91, and 0.79, respectively. Histopathological examination demonstrated minimal damage to non-targeted tissues and caused significant damage to the tumor. This theranostic methodology enhances anti-cancer therapeutic efficiency, and announces the potential for pre-clinical cancer therapy.

The influence of Gd-DOTA ratios conjugating PLGA-PEG micelles encapsulated IR-1061 in bimodal over–1000 nm near–infrared fluorescence and magnetic resonance imaging

Multimodal imaging can provide multidimensional information for understanding concealed microstructures or bioprocesses in biological objects. The combination of over–1000 nm near–infrared (OTN–NIR) fluorescence imaging and magnetic resonance (MR) imaging is...

Dual-targeting SERS-encoded graphene oxide nanocarrier for intracellular co-delivery of doxorubicin and 9-aminoacridine with enhanced combination therapy

A graphene oxide (GO)-based nanocarrier that imparts tumor-selective delivery of dual-drug with enhanced therapeutic index, is introduced. GO is conjugated with Au@Ag and Fe₃O₄ nanoparticles, which facilitates it with SERS tracking and magnetic targeting abilities, followed by the covalent binding of the anti-HER2 antibody, thus allowing it to both actively and passively target SKBR3 cells, human breast cancer cells expressed with HER2. Intracellular drug delivery behaviors are probed using SERS spectroscopy in a spatiotemporal manner, which demonstrates that nanocarriers are internalized into the lysosomes and release the drug in response to the acidic microenvironment. The nanocarriers loaded with dual-drug possess increased cancer cytotoxicity in comparison to those loaded with a single drug. Attractively, the enhanced cytotoxicity against cancer cells is achieved with relatively low concentrations of the drug, which is demonstrated to be involved in the drug adsorption status. These results may give us the new prospects to design GO-based delivery systems with rational drug dosages, thus achieving optimal therapeutic response of the multi-drug with increased tumor selectivity and reduced side effects.

Nanotheranostics With the Combination of Improved Targeting, Therapeutic Effects, and Molecular Imaging

There is an increasing interest in the design of targeted carrier systems with combined therapeutic and diagnostic modalities. Therapeutic modalities targeting tumors with single ligand-based targeting nanocarriers are insufficient for proficient delivery and for targeting two different surface receptors that are overexpressed in cancer cells. Here, we evaluated an activated nanoparticle delivery system comprising fucoidan/hyaluronic acid to improve therapeutic efficacy. The system comprised polyethylene glycol-gelatin-encapsulated epigallocatechin gallate (EGCG), poly (D,L-lactide-co-glycolide; PLGA), and stable iron oxide nanoparticles (IOs). The latter enables targeting of prostate cancers in their molecular images. We demonstrate the transfer of nanoparticles and their entry into prostate cancer cells through ligand-specific recognition. This system may prove the benefits of drug delivery that enhances the inhibition of cell growth through apoptosis induction. Moreover, the improved targeting of nanotheranostics significantly suppressed orthotopic prostate tumor growth and more accurately targeted tumors compared with systemic combination therapy. In the presence of nanoparticles with iron oxides, the hypointensity of the prostate tumor was visualized on a T2-weignted magnetic resonance image. The diagnostic ability of this system was demonstrated by accumulating fluorescent nanoparticles in the prostate tumor from the in vivo imaging system, computed tomography. It is suggested that theranostic nanoparticles combined with a molecular imaging system can be a promising cancer therapy in the future.

Dual-targeted photothermal agents for enhanced cancer therapy

Photothermal therapy, in which light is converted into heat and triggers local hyperthermia to ablate tumors, presents an inherently specific and noninvasive treatment for tumor tissues. In this area, the development of efficient photothermal agents (PTAs) has always been a central topic. Although many efforts have been made on the investigation of novel molecular architectures and photothermal materials over the past decades, PTAs can cause severe damage to normal tissues because of the poor tumor aggregate ability and high irradiation density. Recently, dual-targeted photothermal agents (DTPTAs) provide an attractive strategy to overcome these problems and enhance cancer therapy. DTPTAs are functionalized with two classes of targeting units, including tumor environment targeting sites, tumor targeting sites and organelle targeting sites. In this perspective, typical targeted ligands and representative examples of photothermal therapeutic agents with dual-targeted properties are systematically summarized and recent advances using DTPTAs in tumor therapy are highlighted.

Recent Advances in Magnetic Upconversion Nanocomposites for Bioapplications

The combination of magnetism and upconversion luminescent property into one single nanostructure is fascinating for biological fields, such as multimodal bioimaging, targeted drug delivery, and imaging-guided therapy. In this review, we will provide the state-of-the-art advances on magnetic upconversion nanocomposites towards their bioapplications. Their structure design, synthesis methods, surface engineering and applications in bioimaging, drug delivery, therapy as well as biodetection will be covered.

Construction and evaluation of tumor nucleus-targeting nanocomposite for cancer dual-mode imaging - Guiding photodynamic therapy/photothermal therapy

To tackle the barrier of the insufficient intra-cellular delivery of reactive oxygen species (ROS) and heat, we designed a multifunctional nanoplatform to release ROS and heat directly in the cell nucleus for enhancing combined photodynamic therapy (PDT) and photothermal therapy (PTT) of tumors. As a photothermal agent, WS₂ nanoparticles were adsorbed photosensitive Au₂₅(Captopril)₁₈^- (Au₂₅) nanoclusters via electrostatic interaction. And Dexamethasone (Dex), a glucocorticoid with nucleus targeting capability, played a key role in the intra-nuclear process of heat and ROS. PTT can increase intra-tumoral blood flow to promote Au₂₅ produce more ROS for PDT. Under near infrared (NIR) laser irradiation at a single 808 nm, these nucleus targeting WS₂ nanoplatforms showed a significant decreased cell viability of 18.2 ± 1.7% and a high DNA damage degree of 59.6 ± 8.3%. Furthermore, the WS₂ nanoplatform could be further used for X-ray computed tomography (CT) images. Taken together, our study provided a new prospect for effectively diagnostic and enhancing PTT/PDT efficacy.

Development of an interactive tumor vascular suppression strategy to inhibit multidrug resistance and metastasis with pH/H2O2 responsive and oxygen-producing nanohybrids

An ideal cancer therapeutic strategy should not only reverse multidrug resistance (MDR), but also prevent cancer metastasis. In this study, we address these cancer treatment challenges through an interactive vascular suppression strategy.

Oxygen Self-Production Red Blood Cell Carrier System for MRI Mediated Cancer Therapy: Ferryl-Hb, Sonodynamic, and Chemical Therapy

Hypoxia in tumors can lead to insufficient oxygen supply during sonodynamic therapy (SDT), which in turn strengthens tumor resistance to sonodynamic efficacy. To conquer hypoxia in tumors and improve the treatment effectiveness, we developed oxygen self-production red blood cell (RBC) carrier system to decompose tumor endogenic H₂O₂ into O₂ and combine triplex cancer therapy: ferryl-hemoglobin (ferryl-Hb), sonodynamic, and chemical therapy. Both hydrophilic sonosensitizer and doxorubicin (DOX) were encapsulated inside RBCs (DOX/Mn-TPPS@RBCs). The drug release can be improved by combining the effects of H₂O₂ and ultrasonic irradiation. Here, we introduced a contrast agent, meso-tetra (4-sulfonatephenyl) porphyrinate manganese(III) complex (Mn-TPPS), which could be used to enhance the signal intensity of magnetic resonance imaging (MRI) of the tumor site. The feasibility of Mn-TPPS as a sonosensitizer was investigated during SDT. Importantly, DOX/Mn-TPPS@RBCs overcame hypoxia in the tumor and improved the efficacy of SDT owing to the O₂ generation by the catalase-catalyzed decomposition of tumor endogenic H₂O₂. Hemoglobin was simultaneously oxidized into highly oxidative ferryl-Hb species by H₂O₂ and reactive oxygen species, resulting in cytotoxicity. Overall, this drug delivery system is a promising therapeutic agent involving in situ production of oxygen inside the tumor, triplex therapy, and MRI.

Fe₃O₄ Nanoparticles in Targeted Drug/Gene Delivery Systems

Fe₃O₄ nanoparticles (NPs), the most traditional magnetic nanoparticles, have received a great deal of attention in the biomedical field, especially for targeted drug/gene delivery systems, due to their outstanding magnetism, biocompatibility, lower toxicity, biodegradability, and other features. Naked Fe₃O₄ NPs are easy to aggregate and oxidize, and thus are often made with various coatings to realize superior properties for targeted drug/gene delivery. In this review, we first list the three commonly utilized synthesis methods of Fe₃O₄ NPs, and their advantages and disadvantages. In the second part, we describe coating materials that exhibit noticeable features that allow functionalization of Fe₃O₄ NPs and summarize their methods of drug targeting/gene delivery. Then our efforts will be devoted to the research status and progress of several different functionalized Fe₃O₄ NP delivery systems loaded with chemotherapeutic agents, and we present targeted gene transitive carriers in detail. In the following section, we illuminate the most effective treatment systems of the combined drug and gene therapy. Finally, we propose opportunities and challenges of the clinical transformation of Fe₃O₄ NPs targeting drug/gene delivery systems.

Drug "Pent-Up" in Hollow Magnetic Prussian Blue Nanoparticles for NIR-Induced Chemo-Photothermal Tumor Therapy with Trimodal Imaging

The study reports a biocompatible smart drug delivery system based on a doxorubicin (DOX) blending phase-change material of 1-pentadecanol loaded hollow magnetic Prussian blue nanoparticles, resulting in HMNP-PB@Pent@DOX. The system possesses concentration-dependent high thermogenesis (>50 °C) when applying a near-infrared (NIR) laser irradiation only for 5 min. Furthermore, the system realizes near "zero release" of drug and is efficiently triggered by NIR for drug delivery in an "on" and "off" manner, thus inducing cell apoptosis in vitro and in vivo. Moreover, the system clearly indicates tumor site with trimodal imaging of magnetic resonance imaging, photoacoustic tomography imaging, and infrared thermal imaging. Furthermore, the system achieves efficient chemo-photothermal combined tumor therapy in vivo with 808 nm laser irradiation for 5 min at 1.2 W cm-2 , revealing the good tumor inhibition effect comparing with those of chemotherapy or photothermal therapy alone. The system is also confirmed to be biocompatible in regard to the mortality rate.

Advanced optoacoustic methods for multiscale imaging of in vivo dynamics

Visualization of dynamic functional and molecular events in an unperturbed in vivo environment is essential for understanding the complex biology of living organisms and of disease state and progression. To this end, optoacoustic (photoacoustic) sensing and imaging have demonstrated the exclusive capacity to maintain excellent optical contrast and high resolution in deep-tissue observations, far beyond the penetration limits of modern microscopy. Yet, the time domain is paramount for the observation and study of complex biological interactions that may be invisible in single snapshots of living systems. This review focuses on the recent advances in optoacoustic imaging assisted by smart molecular labeling and dynamic contrast enhancement approaches that enable new types of multiscale dynamic observations not attainable with other bio-imaging modalities. A wealth of investigated new research topics and clinical applications is further discussed, including imaging of large-scale brain activity patterns, volumetric visualization of moving organs and contrast agent kinetics, molecular imaging using targeted and genetically expressed labels, as well as three-dimensional handheld diagnostics of human subjects.

Functional hollow nanostructures for imaging and phototherapy of tumors

Various types of inorganic and organic phototherapeutic hollow nanostructures for the imaging and treatment of tumors are reviewed.

Recent advances in different modal imaging-guided photothermal therapy

Photothermal therapy (PTT) has recently attracted considerable attention owing to its controllable treatment process, high tumour eradication efficiency and minimal side effects on non-cancer cells. PTT can melt cancerous cells by localising tissue hyperthermia induced by internalised therapeutic agents with a high photothermal conversion efficiency under external laser irradiation. Numerous in vitro and in vivo studies have shown the significant potential of PTT to treat tumours in future practical applications. Unfortunately, the lack of visualisation towards agent delivery and internalisation, as well as imaging-guided comprehensive evaluation of therapeutic outcome, limits its further application. Developments in combined photothermal therapeutic nanoplatforms guided by different imaging modalities have compensated for the major drawback of PTT alone, proving PTT to be a promising technique in biomedical applications. In this review, we introduce recent developments in different imaging modalities including single-modal, dual-modal, triple-modal and even multi-modal imaging-guided PTT, together with imaging-guided multi-functional theranostic nanoplatforms.