Hyaluronidase-Responsive Mesoporous Silica Nanoparticles with Dual-Imaging and Dual-Target Function

Targeting overexpressed surface proteins: A new strategy to manage the recalcitrant triple-negative breast cancer

Triple-negative breast cancer (TNBC) is an aggressive and heterogeneous cancer that lacks all three molecular markers, Estrogen, Progesterone, and Human Epidermal Growth Factor Receptor 2 (HER2). This unique characteristic of TNBC makes it more resistant to hormonal therapy; hence, chemotherapy and surgery are preferred. Active targeting with nanoparticles is more effective in managing TNBC than a passive approach. The surface of TNBC cells overexpresses several cell-specific proteins, which can be explored for diagnostic and therapeutic purposes. Immunohistochemical analysis has revealed that TNBC cells overexpress αVβ3 integrin, Intercellular Adhesion Molecule 1 (ICAM-1), Glucose Transporter 5 (GLUT5), Transmembrane Glycoprotein Mucin 1 (MUC-1), and Epidermal Growth Factor Receptor (EGFR). These surface proteins can be targeted using ligands, such as aptamers, antibodies, and sugar molecules. Targeting the surface proteins of TNBC with ligands helps harmonize treatment and improve patient compliance. In this review, we discuss the proteins expressed, which are limited to αVβ3 integrin proteins, ICAM-1, GLUT-5, MUC1, and EGFR, on the surface of TNBC, the challenges associated with the preclinical setup of breast cancer for targeted nanoformulations, internalization techniques and their challenges, suggestions to overcome the limitations of successful translation of nanoparticles, and the possibility of ligand-conjugated nanoparticles targeting these surface receptors for a better therapeutic outcome.

Mesoporous Graphene Oxide Nanocomposite Effective for Combined Chemo/Photo Therapy Against Non-Small Cell Lung Cancer

Introduction

Lung cancer is the most common cancer worldwide, among which non-small cell lung cancer (NSCLC) accounts for about 80% of all lung cancers. Chemotherapy, a mainstay modality for NSCLC, has demonstrated restricted effectiveness due to the emergence of chemo-resistance and systemic side effects. Studies have indicated that combining chemotherapy with phototherapy, such as photodynamic therapy (PDT) and photothermal therapy (PTT), can enhance efficacy of therapy. In this work, an aminated mesoporous graphene oxide (rPGO)-protoporphyrin IX (PPIX)-hyaluronic acid (HA)@Osimertinib (AZD) nanodrug delivery system (rPPH@AZD) was successfully developed for combined chemotherapy/phototherapy for NSCLC.

Methods

A pH/hyaluronidase-responsive nanodrug delivery system (rPPH@AZD) was prepared using mesoporous graphene oxide. Its morphology, elemental composition, surface functional groups, optical properties, in vitro drug release ability, photothermal properties, reactive oxygen species production, cellular uptake and cell viability were evaluated. In addition, the in vivo therapeutic effect, biocompatibility, and imaging capabilities of rPPH@AZD were verified by a tumor-bearing mouse model.

Results

Aminated mesoporous graphene oxide (rPGO) plays a role as a drug delivery vehicle owing to its large specific surface area and ease of surface functionalization. rPGO exhibits excellent photothermal conversion properties under laser irradiation, while PPIX acts as a photosensitizer to generate singlet oxygen. AZD acts as a small molecule targeted drug in chemotherapy. In essence, rPPH@AZD shows excellent photothermal and fluorescence imaging effects in tumor-bearing mice. More importantly, in vitro and in vivo results indicate that rPPH@AZD can achieve hyaluronidase/pH dual response as well as combined chemotherapy/PTT/PDT anti-NSCLC treatment.

Conclusion

The newly prepared rPPH@AZD can serve as a promising pH/hyaluronidase-responsive nanodrug delivery system that integrates photothermal/fluorescence imaging and chemo/photo combined therapy for efficient therapy against NSCLC.

Conjugated Nanoparticles for Solid Tumor Theranostics: Unraveling the Interplay of Known and Unknown Factors

Cancer diagnoses have been increasing worldwide, and solid tumors are among the leading contributors to patient mortality, creating an enormous burden on the global healthcare system. Cancer is responsible for around 10.3 million deaths worldwide. Solid tumors are one of the most prevalent cancers observed in recent times. On the other hand, early diagnosis is a significant challenge that could save a person's life. Treatment with existing methods has pitfalls that limit the successful elimination of the disorder. Though nanoparticle-based imaging and therapeutics have shown a significant impact in healthcare, current methodologies for solid tumor treatment are insufficient. There are multiple complications associated with the diagnosis and management of solid tumors as well. Recently, surface-conjugated nanoparticles such as lipid nanoparticles, metallic nanoparticles, and quantum dots have shown positive results in solid tumor diagnostics and therapeutics in preclinical models. Other nanotheranostic material platforms such as plasmonic theranostics, magnetotheranostics, hybrid nanotheranostics, and graphene theranostics have also been explored. These nanoparticle theranostics ensure the appropriate targeting of tumors along with selective delivery of cargos (both imaging and therapeutic probes) without affecting the surrounding healthy tissues. Though they have multiple applications, nanoparticles still possess numerous limitations that need to be addressed in order to be fully utilized in the clinic. In this review, we outline the importance of materials and design strategies used to engineer nanoparticles in the treatment and diagnosis of solid tumors and how effectively each method overcomes the drawbacks of the current techniques. We also highlight the gaps in each material platform and how design considerations can address their limitations in future research directions.

Functionalized europium-doped hollow mesoporous silica nanospheres as a cell imaging and drug delivery agents

In an effort to enhance the antitumor efficacy of breast cancer treatment, the chemotherapeutic agent Paclitaxel (PTX) was encapsulated within hyaluronic acid (HA) modified hollow mesoporous silica (HMSNs). In vitro drug release assays showed that the resulting formulation, Eu-HMSNs-HA-PTX, exhibited enzyme-responsive drug release. In addition, cell cytotoxicity and hemolysis assays demonstrated the favorable biocompatibility of both Eu-HMSNs and Eu-HMSNs-HA. Notably, compared to Eu-HMSNs alone, Eu-HMSNs-HA showed enhanced accumulation within CD44-expressing cancer cells (MDA-MB-231). As anticipated, apoptosis experiments indicated that Eu-HMSNs-HA-PTX displayed significantly greater cytotoxicity toward MDA-MB-231 cells than non-targeted Eu-HMSNs-PTX and free PTX. In conclusion, Eu-HMSNs-HA-PTX demonstrated excellent anticancer effects and holds promise as a potent candidate for the efficient therapy of breast cancer.

Mesoporous silica nanoparticles with dual-targeting agricultural sources for enhanced cancer treatment via tritherapy

In this study, we introduced dual-targeting folic acid (FA) and hyaluronic acid (HA) modified on the surface of rice husk mesoporous silica nanoparticles (rMSNs). The rMSNs were employed as a drug delivery system loaded with camptothecin (CPT) as a model drug, Eu³⁺ ions as a photosensitizer for photodynamic therapy (PDT), bismuth (Bi) for photothermal therapy (PTT), and Gd³⁺ ions for magnetic resonance imaging (MRI) to develop novel nanoparticles, rMSN-EuGd-Bi@CPT-HA-FA, with dual-targeted function and triple therapy for cancer treatment. The results of the cell cytotoxicity experiment showed that the A549 cancer cells had a survival rate of approximately 35% when treated with 200 μg mL^-1 of rMSN-EuGd-Bi@CPT-HA-FA under 808 nm irradiation for 15 min. The dual-targeted function and synergistic treatment of CPT, PTT, and PDT were also responsible for the 20% survival rate of the A549 cancer cells treated with 200 μg mL^-1 of rMSN-EuGd-Bi@CPT-HA-FA under 808 nm irradiation for 30 min. The results showed that rMSN-EuGd-Bi@CPT-HA-FA can effectively combine chemotherapy (through CPT), PDT, and PTT for cancer treatment.

Multi-Targeted and On-Demand Non-Coding RNA Regulation Nanoplatform against Metastasis and Recurrence of Triple-Negative Breast Cancer

Dysregulation of microRNAs (miRs) is the hallmark of triple-negative breast cancer (TNBC), which is closely involved with its growth, metastasis, and recurrence. Dysregulated miRs are promising targets for TNBC therapy, however, targeted and accurate regulation of multiple disordered miRs in tumors is still a great challenge. Here, a multi-targeting and on-demand non-coding RNA regulation nanoplatform (MTOR) is reported to precisely regulate disordered miRs, leading to dramatical suppression of TNBC growth, metastasis, and recurrence. With the assistance of long blood circulation, ligands of urokinase-type plasminogen activator peptide and hyaluronan located in multi-functional shells enable MTOR to actively target TNBC cells and breast cancer stem cell-like cells (BrCSCs). After entering TNBC cells and BrCSCs, MTOR is subjected to lysosomal hyaluronidase-induced shell detachment, leading to an explosion of the TAT-enriched core, thereby enhancing nuclear targeting. Subsequently, MTOR could precisely and simultaneously downregulate microRNA-21 expression and upregulate microRNA-205 expression in TNBC. In subcutaneous xenograft, orthotopic xenograft, pulmonary metastasis, and recurrence TNBC mouse models, MTOR shows remarkably synergetic effects on the inhibition of tumor growth, metastasis, and recurrence due to its on-demand regulation of disordered miRs. This MTOR system opens a new avenue for on-demand regulation of disordered miRs against growth, metastasis, and recurrence of TNBC.

Hypoxia-responsive covalent organic framework by single NIR laser-triggered for multimodal synergistic therapy of triple-negative breast cancer

In recent years, laser-mediated photodynamic therapy and photothermal therapy have attracted widespread attention due to their minimally invasive, easy to operate characteristics and high specificity. However, the traditional photodynamic or photothermal therapy exist several shortcomings such as the hypoxic microenvironment, intracellular heat shock proteins or complex operation. In this study, covalent organic framework (COF) was used as the drug carrier to equip with the photosensitizer indocyanine green (ICG) and the hypoxia-activating prodrug AQ4N. The hyaluronic acid (HA) was modified on the surface of COF to obtain the HA-COF@ICG/AQ4N drug delivery system. HA-modified COF delivery systems can target tumor cells through recognize CD44 which is overexpressed in the surface of tumor cells membrane. Under the irradiation of single NIR laser, ICG that can excite the nanoplatform simultaneously produces a combined effect of photodynamic and photothermal. At the same time, photodynamic therapy through depleting intracellular oxygen exacerbates the hypoxic state of the tumor microenvironment, which in turn enhances AQ4N reduced to chemotherapeutic drug AQ4, producing a synergistic cascade antitumor effect. The results of our study by tumor cell and tumor spheroids indicated that the hypoxia-activated multi-functional nanoplatform could effectively inhibit the growth and metastasis of triple-negative breast cancer.

pH-Responsive Drug Delivery and Imaging Study of Hybrid Mesoporous Silica Nanoparticles

A system of pH-responsive and imaging nanocarriers was developed using mesoporous silica nanoparticles (MSNs), in which gadolinium (Gd) was doped through in situ doping (Gd₂O₃@MSN). Sodium alginate (SA) was attached to the surfaces of the amino groups of MSNs (NH₂-Gd₂O₃@MSN) through the electrostatic adsorption between the amino groups and the carboxyl groups with the formation of hybrid SA-Gd₂O₃@MSN nanoparticles (NPs). The SA-coated NPs were spherical or near-spherical in shape with an average size of nearly 83.2 ± 8.7 nm. The in vitro drug release experiments of a model rhodamine B (RhB) cargo were performed at different pH values. The result confirmed the pH-responsiveness of the nanocarriers. The results of the cytotoxicity studies indicated that the SA-Gd₂O₃@MSN NPs were not cytotoxic by themselves. The results of the in vivo safety evaluation and the hemolysis assay confirmed that the system is highly biocompatible. It is noteworthy that the T1 contrast of the system was significantly enhanced by the Gd, as indicated by the result of the MR imaging. This study confirms that the synthesized hybrid nanosystem is promising for pH-responsive drug delivery and MR imaging for cancer diagnosis and treatment.

Hyaluronic Acid-Based Nanomaterials Applied to Cancer: Where Are We Now?

Cancer cells normally develop the ability to rewire or reprogram themselves to become resistant to treatments that were previously effective. Despite progress in understanding drug resistance, knowledge gaps remain regarding the underlying biological causes of drug resistance and the design of cancer treatments to overcome it. So, resistance acquisition remains a major problem in cancer treatment. Targeted therapeutics are considered the next generation of cancer therapy because they overcome many limitations of traditional treatments. Numerous tumor cells overexpress several receptors that have a high binding affinity for hyaluronic acid (HA), while they are poorly expressed in normal body cells. HA and its derivatives have the advantage of being biocompatible and biodegradable and may be conjugated with a variety of drugs and drug carriers for developing various formulations as anticancer therapies such as micelles, nanogels, and inorganic nanoparticles. Due to their stability in blood circulation and predictable delivery patterns, enhanced tumor-selective drug accumulation, and decreased toxicity to normal tissues, tumor-targeting nanomaterial-based drug delivery systems have been shown to represent an efficacious approach for the treatment of cancer. In this review, we aim to provide an overview of some in vitro and in vivo studies related to the potential of HA as a ligand to develop targeted nanovehicles for future biomedical applications in cancer treatment.

Silica nanoparticles: Biomedical applications and toxicity

Silica nanoparticles (SiNPs) are composed of silicon dioxide, the most abundant compound on Earth, and are used widely in many applications including the food industry, synthetic processes, medical diagnosis, and drug delivery due to their controllable particle size, large surface area, and great biocompatibility. Building on basic synthetic methods, convenient and economical strategies have been developed for the synthesis of SiNPs. Numerous studies have assessed the biomedical applications of SiNPs, including the surface and structural modification of SiNPs to target various cancers and diagnose diseases. However, studies on the in vitro and in vivo toxicity of SiNPs remain in the exploratory stage, and the toxicity mechanisms of SiNPs are poorly understood. This review covers recent studies on the biomedical applications of SiNPs, including their uses in drug delivery systems to diagnose and treat various diseases in the human body. SiNP toxicity is discussed in terms of the different systems of the human body and the individual organs in those systems. This comprehensive review includes both fundamental discoveries and exploratory progress in SiNP research that may lead to practical developments in the future.

Polysaccharide/mesoporous silica nanoparticle-based drug delivery systems: A review

Mesoporous silica nanoparticles (MSNs) have been well-researched in the design and fabrication of advanced drug delivery systems (DDSs) due to their advantages such as good biocompatibility, large specific surface area and pore volume for drug loading, easily surface modification, adjusted size and good thermal/chemical stability. For MSN-based DDSs, gate materials are also necessary. And natural polysaccharides, one kind of the most abundant natural resource, have been widely applied as the "gatekeepers" in MSN-based DDSs. Polysaccharides are cheap and rich in sources with good biocompatibility, and some of them have important biological functions. In this review article, polysaccharides including chitosan, hyaluronic acid, sodium alginate and dextran, et al. are briefly introduced. And the preparation processes and properties such as controlled drug release, cancer targeting and disease diagnosis of functional polysaccharide/MSN-based DDSs are discussed.

Improving anti-cancer drug delivery performance of magnetic mesoporous silica nanocarriers for more efficient colorectal cancer therapy

BACKGROUND

Improving anti-cancer drug delivery performance can be achieved through designing smart and targeted drug delivery systems (DDSs). For this aim, it is important to evaluate overexpressed biomarkers in the tumor microenvironment (TME) for optimizing DDSs.

MATERIALS AND METHODS

Herein, we designed a novel DDS based on magnetic mesoporous silica core-shell nanoparticles (SPION@MSNs) in which release of doxorubicin (DOX) at the physiologic pH was blocked with gold gatekeepers. In this platform, we conjugated heterofunctional polyethylene glycol (PEG) onto the outer surface of nanocarriers to increase their biocompatibility. At the final stage, an epithelial cell adhesion molecule (EpCAM) aptamer as an active targeting moiety was covalently attached (Apt-PEG-Au@NPs-DOX) for selective drug delivery to colorectal cancer (CRC) cells. The physicochemical properties of non-targeted and targeted nanocarriers were fully characterized. The anti-cancer activity, cellular internalization, and then the cell death mechanism of prepared nanocarriers were determined and compared in vitro. Finally, tumor inhibitory effects, biodistribution and possible side effects of the nanocarriers were evaluated in immunocompromised C57BL/6 mice bearing human HT-29 tumors.

RESULTS

Nanocarriers were successfully synthesized with a mean final size diameter of 58.22 ± 8.54 nm. Higher cytotoxicity and cellular uptake of targeted nanocarriers were shown in the EpCAM-positive HT-29 cells as compared to the EpCAM-negative CHO cells, indicating the efficacy of aptamer as a targeting agent. In vivo results in a humanized mouse model showed that targeted nanocarriers could effectively increase DOX accumulation in the tumor site, inhibit tumor growth, and reduce the adverse side effects.

CONCLUSION

These results suggest that corporation of a magnetic core, gold gatekeeper, PEG and aptamer can strongly improve drug delivery performance and provide a theranostic DDS for efficient CRC therapy.

Imaging cancer cells with nanostructures: Prospects of nanotechnology driven non-invasive cancer diagnosis

The application of nanostructured materials in medicine is a rapidly evolving area of research that includes both the diagnosis and treatment of various diseases. Metals, metal oxides and carbon-based nanomaterials have shown much promise in medical technological advancements due to their tunable physical, chemical and biological properties. The nanoscale properties, especially the size, shape, surface chemistry and stability makes them highly desirable for diagnosing and treating various diseases, including cancers. Major applications of nanomaterials in cancer diagnosis include in vivo bioimaging and molecular marker detection, mainly as image contrast agents using modalities such as radio, magnetic resonance, and ultrasound imaging. When a suitable targeting ligand is attached on the nanomaterial surface, it can help pinpoint the disease site during imaging. The application of nanostructured materials in cancer diagnosis can help in the early detection, treatment and patient follow-up . This review aims to gather and present the information regarding the application of nanotechnology in cancer diagnosis. We also discuss the challenges and prospects regarding the application of nanomaterials as cancer diagnostic tools.

Endogenous Enzyme-responsive Nanoplatforms for Anti-tumor Therapy

The emergency of responsive drug delivery systems has contributed to reduced cytotoxicity, improved permeability in tissues and extended circulation time of the active drug. In particular, enzyme-responsive nanoplatforms have attracted a lot of attention due to the specificity and efficiency of an enzyme-catalyzed reaction. In this review, enzyme-based mono responsive drug delivery systems designed in the past 5 years have been summarized. These drug delivery systems were introduced by different tumor-related enzymes such as matrix metalloproteinase, esterase, hyaluronidase, caspase and cathepsin. Moreover, the enzyme-sensitive nanoplatforms activated by dual-stimuli have been also described. Although great progress had been made in the past years, the translation into clinical practice is still difficult. Thus, three obstacles (enzyme heterogeneity, reaction environment, animal model) were also discussed. In short, enzyme-activated drug delivery systems offer great potential in treating cancers.

Stimuli-responsive mesoporous silica nanoparticles: A custom-tailored next generation approach in cargo delivery

The pre-mature release of therapeutic cargos in the bloodstream or off-target sites is a major hurdle in drug delivery. However, stimuli-specific drug release responses are capable of providing greater control over the cargo release. Herein, various types of nanocarriers have been employed for such applications. Among various types of nanoparticles, mesoporous silica nanoparticles (MSNPs) have several attractive characteristics, such as high loading capacity, biocompatibility, small size, porous structure, high surface area, tunable pore size and ease of functionalization of the external and internal surfaces, which facilitates the entrapment and development of stimuli-dependent release of drugs. MSNPs could be modified with such stimuli-responsive entities like nucleic acid, peptides, polymers, organic molecules, etc., to prevent pre-mature cargo release, improving the therapeutic outcome. This controlled drug release system could be modulated to function upon extracellular or intracellular specific stimuli, including pH, enzyme, glucose, glutathione, light, temperature, etc., and thus provide minimal side effects at non-target sites. This system has great potential applications for the targeted delivery of therapeutics to treat clinically challenging diseases like cancer. This review summarizes the synthesis and design of stimuli-responsive release strategies of MSNP-based drug delivery systems along with investigations in biomedical applications.

Mesoporous Silica Nanoparticles for Targeting Subcellular Organelles

Current chemotherapy treatments lack great selectivity towards tumoral cells, which leads to nonspecific drug distribution and subsequent side effects. In this regard, the use of nanoparticles able to encapsulate and release therapeutic agents has attracted growing attention. In this sense, mesoporous silica nanoparticles (MSNs) have been widely employed as drug carriers owing to their exquisite physico-chemical properties. Because MSNs present a surface full of silanol groups, they can be easily functionalized to endow the nanoparticles with many different functionalities, including the introduction of moieties with affinity for the cell membrane or relevant compartments within the cell, thus increasing the efficacy of the treatments. This review manuscript will provide the state-of-the-art on MSNs functionalized for targeting subcellular compartments, focusing on the cytoplasm, the mitochondria, and the nucleus.

Cancer Nanomedicine

This Special Issue on Cancer Nanomedicine within Cancers brings together 46 cutting-edge papers covering research within the field along with insightful reviews and opinions reflecting our community [...].