Carboxymethyl dextran-based nanocomposites for enhanced chemo-sonodynamic therapy of cancer

Ultrasensitive detection platform for Staphylococcus aureus based on DNAzyme tandem blocking CRISPR/Cas12a system

Detection methods based on CRISPR/Cas12a have been widely developed in the application of pathogenic microorganisms to guarantee food safety and public health. For sensitive detection, the CRISPR-based strategies are often in tandem with amplification methods. However, that may increase the detection time and the process may introduce nucleic acid contamination resulting in non-specific amplification. Herein, we established a sensitive S. aureus detection strategy based on the CRISPR/Cas12a system combined with DNAzyme. The activity of Cas12a is blocked by extending the spacer of crRNA (bcrRNA) and can be reactivated by Mn2+. NH2-modified S. aureus-specific aptamer was loaded on the surface of Fe3O4 MNPs (apt-Fe3O4 MNPs) and MnO2 NPs (apt-MnO2 NPs) by EDC/NHS chemistry. The S. aureus was captured to form apt-Fe3O4 MNPs/S. aureus/apt-MnO2 NPs complex and then MnO2 NPs were etched to release Mn2+ to activate DNAzyme. The active DNAzyme can cleave the hairpin structure in bcrRNA to recover the activity of the CRISPR/Cas system. By initiating the whole detection process by generating Mn2+ through nanoparticle etching, we established a rapid detection assay without nucleic acid extraction and amplification process. The proposed strategy has been applied in the ultrasensitive quantitative detection of S. aureus and has shown good performance with an LOD of 5 CFU/mL in 29 min. Besides, the proposed method can potentially be applied to other targets by simply changing the recognition element and has the prospect of developing a universal detection strategy.

Biopolymer-Based Nanomedicine for Cancer Therapy: Opportunities and Challenges

Cancer, as the foremost challenge among human diseases, has plagued medical professionals for many years. While there have been numerous treatment approaches in clinical practice, they often cause additional harm to patients. The emergence of nanotechnology has brought new directions for cancer treatment, which can deliver anticancer drugs specifically to tumor areas. This article first introduces the application scenarios of nanotherapies and treatment strategies of nanomedicine. Then, the noteworthy characteristics exhibited by biopolymer materials were described, which make biopolymers stand out in polymeric nanomedicine delivery. Next, we focus on summarizing the state-of-art studies of five categories of proteins (Albumin, Gelatin, Silk fibroin, Zein, Ferritin), nine varieties of polysaccharides (Chitosan, Starch, Hyaluronic acid, Dextran, cellulose, Fucoidan, Carrageenan, Lignin, Pectin) and liposomes in the field of anticancer drug delivery. Finally, we also provide a summary of the advantages and limitations of these biopolymers, discuss the prevailing impediments to their application, and discuss in detail the prospective research directions. This review not only helps readers understand the current development status of nano anticancer drug delivery systems based on biopolymers, but also is helpful for readers to understand the properties of various biopolymers and find suitable solutions in this field through comparative reading.

Design of lactoferrin functionalized carboxymethyl dextran coated egg albumin nanoconjugate for targeted delivery of capsaicin: Spectroscopic and cytotoxicity studies

The increased mortality rates associated with colorectal cancer highlight the pressing need for improving treatment approaches. While capsaicin (CAP) has shown promising anticancer activity, its efficacy is hampered due to low solubility, rapid metabolism, suboptimal bioavailability, and a short half-life. Therefore, this study aimed to prepare a lactoferrin-functionalized carboxymethyl dextran-coated egg albumin nanoconjugate (LF-CMD@CAP-EGA-NCs) for the targeted CAP delivery to enhance its potential for colorectal cancer therapy. Briefly, LF-CMD was synthesized through an esterification reaction involving LF as a receptor and CMD as a shell. Concurrently, CAP was incorporated into an EGA carrier using gelation and hydrophobic interactions. The subsequent production of LF-CMD@CAP-EGA-NCs was achieved through the Maillard reaction. Spectral characterizations confirmed the successful synthesis of smooth and spherical-shaped LF-CMD@CAP-EGA-NCs using LF-CMD and EGA-CAP nanoparticles, with high entrapment efficiency and satisfactory drug content. Furthermore, LF-CMD@CAP-EGA-NCs demonstrated a sustained release of CAP (76.52 ± 1.01 % in 24 h, R2 = 0.9966) in pH 5.8 buffer with anomalous transport (n = 0.68) owing to the shell of the CMD and EGA matrix. The nanoconjugate exhibited enhanced cytotoxicity in HCT116 and LoVo cell lines, which is attributed to the overexpression of LF receptors in colorectal HCT116 cells. Additionally, LF-CMD@CAP-EGA-NCs demonstrated excellent biocompatibility, as observed in the FHC-CRL-1831 cell line. In conclusion, LF-CMD@CAP-EGA-NCs can be considered as a promising approach for targeted delivery of CAP and other anticancer agents in colorectal cancer treatment.

Improvement of the effectiveness of sonodynamic therapy: by optimizing components and combination with other treatments

Sonodynamic therapy (SDT) is an emerging treatment method. In comparison with photodynamic therapy (PDT), SDT exhibits deep penetration, high cell membrane permeability, and free exposure to light capacity. Unfortunately, owing to inappropriate ultrasound parameter selection, poor targeting of sonosensitizers, and the complex tumor environment, SDT is frequently ineffective. In this review, we describe the approaches for selecting ultrasound parameters and how to develop sonosensitizers to increase targeting and improve adverse tumor microenvironments. Furthermore, the potential of combining SDT with other treatment methods, such as chemotherapy, chemodynamic therapy, photodynamic therapy, photothermal therapy, and immunotherapy, is discussed to further increase the treatment efficiency of SDT.

Recent Developments of Inorganic Nanosensitizers for Sonodynamic Therapy

As a noninvasive treatment, sonodynamic therapy (SDT) has been widely used in the treatment of tumors because of its ability to penetrate deep tissue with few side effects. As the key factor of SDT, it is meaningful to design and synthesize efficient sonosensitizers. Compared with organic sonosensitizers, inorganic sonosensitizers can be easily excited by ultrasound. In addition, inorganic sonosensitizers with stable properties, good dispersion, and long blood circulation time, have great development potential in SDT. This review summarizes possible mechanisms of SDT (sonoexcitation and ultrasonic cavitation) in detail. Based on these mechanisms, the design and synthesis of inorganic nanosonosensitizers can be divided into three categories: traditional inorganic semiconductor sonosensitizers, enhanced inorganic semiconductor sonosensitizers, and cavitation-enhanced sonosensitizers. Subsequently, the current efficient construction methods of sonosensitizers are summarized including accelerated semiconductor charge separation and enhanced production of reactive oxygen species through ultrasonic cavitation. Furthermore, the advantages and disadvantages of different inorganic sonosensitizers and detailed strategies are systematically discussed on how to enhance SDT. Hopefully, this review could provide new insights into the design and synthesis of efficient inorganic nano-sonosensitizers for SDT.

Advances in tumor nanotechnology: theragnostic implications in tumors via targeting regulated cell death

Cell death constitutes an indispensable part of the organismal balance in the human body. Generally, cell death includes regulated cell death (RCD) and accidental cell death (ACD), reflecting the intricately molecule-dependent process and the uncontrolled response, respectively. Furthermore, diverse RCD pathways correlate with multiple diseases, such as tumors and neurodegenerative diseases. Meanwhile, with the development of precision medicine, novel nano-based materials have gradually been applied in the clinical diagnosis and treatment of tumor patients. As the carrier, organic, inorganic, and biomimetic nanomaterials could facilitate the distribution, improve solubility and bioavailability, enhance biocompatibility and decrease the toxicity of drugs in the body, therefore, benefiting tumor patients with better survival outcomes and quality of life. In terms of the most studied cell death pathways, such as apoptosis, necroptosis, and pyroptosis, plenty of studies have explored specific types of nanomaterials targeting the molecules and signals in these pathways. However, no attempt was made to display diverse nanomaterials targeting different RCD pathways comprehensively. In this review, we elaborate on the potential mechanisms of RCD, including intrinsic and extrinsic apoptosis, necroptosis, ferroptosis, pyroptosis, autophagy-dependent cell death, and other cell death pathways together with corresponding nanomaterials. The thorough presentation of RCD pathways and diverse nano-based materials may provide a wider cellular and molecular landscape of tumor diagnosis and treatments.

Biomedical applications of MnO2 nanomaterials as nanozyme-based theranostics

Manganese dioxide (MnO₂) nanoenzymes/nanozymes (MnO₂-NEs) are 1-100 nm nanomaterials that mimic catalytic, oxidative, peroxidase, and superoxide dismutase activities. The oxidative-like activity of MnO₂-NEs makes them suitable for developing effective and low-cost colorimetric detection assays of biomolecules. Interestingly, MnO₂-NEs also demonstrate scavenging properties against reactive oxygen species (ROS) in various pathological conditions. In addition, due to the decomposition of MnO₂-NEs in the tumor microenvironment (TME) and the production of Mn²⁺, they can act as a contrast agent for improving clinical imaging diagnostics. MnO₂-NEs also can use as an in situ oxygen production system in TME, thereby overcoming hypoxic conditions and their consequences in the progression of cancer. Furthermore, MnO₂-NEs as a shell and coating make the nanosystems smart and, therefore, in combination with other nanomaterials, the MnO₂-NEs can be used as an intelligent nanocarrier for delivering drugs, photosensitizers, and sonosensitizers in vivo. Moreover, these capabilities make MnO₂-NEs a promising candidate for the detection and treatment of different human diseases such as cancer, metabolic, infectious, and inflammatory pathological conditions. MnO₂-NEs also have ROS-scavenging and anti-bacterial properties against Gram-positive and Gram-negative bacterial strains, which make them suitable for wound healing applications. Given the importance of nanomaterials and their potential applications in biomedicine, this review aimed to discuss the biochemical properties and the theranostic roles of MnO₂-NEs and recent advances in their use in colorimetric detection assays of biomolecules, diagnostic imaging, drug delivery, and combinatorial therapy applications. Finally, the challenges of MnO₂-NEs applications in biomedicine will be discussed.

Dextran Formulations as Effective Delivery Systems of Therapeutic Agents

Dextran is by far one of the most interesting non-toxic, bio-compatible macromolecules, an exopolysaccharide biosynthesized by lactic acid bacteria. It has been extensively used as a major component in many types of drug-delivery systems (DDS), which can be submitted to the next in-vivo testing stages, and may be proposed for clinical trials or pharmaceutical use approval. An important aspect to consider in order to maintain high DDS' biocompatibility is the use of dextran obtained by fermentation processes and with a minimum chemical modification degree. By performing chemical modifications, artefacts can appear in the dextran spatial structure that can lead to decreased biocompatibility or even cytotoxicity. The present review aims to systematize DDS depending on the dextran type used and the biologically active compounds transported, in order to obtain desired therapeutic effects. So far, pure dextran and modified dextran such as acetalated, oxidised, carboxymethyl, diethylaminoethyl-dextran and dextran sulphate sodium, were used to develop several DDSs: microspheres, microparticles, nanoparticles, nanodroplets, liposomes, micelles and nanomicelles, hydrogels, films, nanowires, bio-conjugates, medical adhesives and others. The DDS are critically presented by structures, biocompatibility, drugs loaded and therapeutic points of view in order to highlight future therapeutic perspectives.

Evading Doxorubicin-Induced Systemic Immunosuppression Using Ultrasound-Responsive Liposomes Combined with Focused Ultrasound

Doxorubicin (DOX) is a representative anticancer drug with a unique ability to induce immunogenic cell death of cancer cells. However, undesired toxicity on immune cells has remained a significant challenge, hindering the usage of DOX in cancer immunotherapy. Here, we report a combined therapy to avoid the off-target toxicity of DOX by adapting ultrasound-responsive liposomal doxorubicin and focused ultrasound exposure. Histological analysis demonstrated that the combined therapy induced less hemosiderosis of splenocytes and improved tumor infiltration of cytotoxic T lymphocytes. Additionally, in vivo therapeutic evaluation results indicate that the combined therapy achieved higher efficacy when combined with PD-1 immune-checkpoint blockade therapy by improving immunogenicity.

Integrated Platform of Oxygen Self-enriched Nanovesicles: SP94 Peptide-directed Chemo/sonodynamic Therapy for Liver Cancer

Hepatocellular carcinoma (HCC) is a most common primary liver cancer among the most deadly malignancies. Selectively killing the cancer cells within the liver urgently requires the novel treatment strategies. The combination of sonodynamic therapy (SDT) and chemotherapy based on the nanotechnology have achieved some achievements in the HCC treatments. However, off-targeting drug delivery to healthy cells and the hypoxic microenvironment in the solid tumors frustrate the efforts to the combined strategy. The hypoxic microenvironment restrains the generation of ROS, leading to the decreased effects of SDT. To improve the clinical outcomes of chemo/SDT strategy, we created a novel oxygen self-enriched active targeted nanovesicle (ICG-DOX NPs/PFH@SP94-Lip). SP94 peptide could enhance the selectivity of the nanovesicles to liver tumor cells rather than normal liver cells. Besides, an oxygen carrier, perfluorohexanes (PFH), was co-loaded into liposomes to increase the oxygen level in tumor tissue, thus improving the effects of SDT. The in vivo studies showed that the ICG-DOX NPs/PFH@SP94-Lip combined with the external US stimulation significantly inhibited effects on tumor growth. Therefore, this novel oxygen self-enriched chemo/SDT nanocomposites represents a proof-of-concept liver tumor treatment strategy.

Excited state and reactive oxygen species against cancer and pathogens: a review on sonodynamic and sono-photodynamic therapy

Photodynamic and sonodynamic therapy are therapies having great potential in the treatment of bacterial infections and cancer. Their background is associated with photo- and sonosensitizers - substances that can be excited when exposed to light or ultrasound. These sensitizers belong to a variety of compounds groups, including porphyrins, porphyrazines, and phthalocyanines. Releasing the energy when returning to the ground state can occur in the manner of transferring it to oxygen molecules, leading to reactive oxygen species able to disrupt membranes of bacterial and cancer cells, leaving the organism's cells unaffected. In recent years, the number of reports on numerous sensitizers being effective has been constantly growing. Therefore, the development of this field may prove beneficial for dealing with cancer and microbes. This review describes the development of photodynamic and sonodynamic therapy, as well as their combination, with emphasize on sonodynamic therapy and its potential in the treatment of cancer and bacterial infections.

Exosome-Mediated Therapeutic Strategies for Management of Solid and Hematological Malignancies

Exosomes are small membrane vesicles of endocytic origin containing cytokines, RNAs, growth factors, proteins, lipids, and metabolites. They have been identified as fundamental intercellular communication controllers in several diseases and an enormous volume of data confirmed that exosomes could either sustain or inhibit tumor onset and diffusion in diverse solid and hematological malignancies by paracrine signaling. Thus, exosomes might constitute a promising cell-free tumor treatment alternative. This review focuses on the effects of exosomes in the treatment of tumors, by discussing the most recent and promising data from in vitro and experimental in vivo studies and the few existing clinical trials. Exosomes are extremely promising as transporters of drugs, antagomir, genes, and other therapeutic substances that can be integrated into their core via different procedures. Moreover, exosomes can augment or inhibit non-coding RNAs, change the metabolism of cancer cells, and modify the function of immunologic effectors thus modifying the tumor microenvironment transforming it from pro-tumor to antitumor milieu. Here, we report the development of currently realized exosome modifiers that offer indications for the forthcoming elaboration of other more effective methods capable of enhancing the activity of the exosomes.

Application of nanosonosensitizer materials in cancer sono-dynamic therapy

Sonodynamic therapy (SDT) is a novel non-invasive treatment for cancer combining low-intensity ultrasound and sonosensitizers.

Gold-installed hyaluronic acid hydrogel for ultrasound-triggered thermal elevation and on-demand cargo release

The temporal and quantitative control of the cargo release is a challenging issue in the application of hydrogels for cancer therapy. Here, we report hyaluronic acid hydrogel-based depot that provides ultrasound-triggered thermal elevation and on-demand cargo release. The hyaluronic acid hydrogel was developed by employing the gold cluster as a sonothermal crosslinker which was grown on the cargo to prevent its undesired leakage until ultrasound-induced dissociation. The results demonstrated that, in the presence of ultrasound at 30 W, the hyaluronic acid hydrogel significantly increased the temperature to 53.7 °C, leading to dissociation of gold clusters and subsequent cargo release. In addition, the prepared hydrogel exhibited appropriate mechanical properties and superior biostability as an injectable hydrogel for in vivo applications.