The Penetrated Delivery of Drug and Energy to Tumors by Lipo-Graphene Nanosponges for Photolytic Therapy

Direct Membrane Penetration and Cytosolic Delivery of Nanoparticles via Electrostatically Bound Amphiphiles

Nanoparticles usually enter cells through energy-dependent endocytosis that involves their cytosolic entry via biomembrane-coated endosomes. In contrast, direct translocation of nanoparticles with straight access to cytosol/subcellular components without any membrane coating is limited to very selective conditions/approaches. Here we show that nanoparticles can switch from energy-dependent endocytosis to energy-independent direct membrane penetration once an amphiphile is electrostatically bound to their surface. Compared to endocytotic uptake, this direct cell translocation is faster and nanoparticles are distributed inside the cytosol without any lysosomal trafficking. We found that this direct cell translocation option is sensitive to the charges of both the nanoparticles and the amphiphile. We propose that an electrostatically bound amphiphile induces temporary opening of the cell membrane, which allows direct cell translocation of nanoparticles. This approach can be adapted for efficient subcellular targeting of nanoparticles and nanoparticle-based drug delivery application, bypassing the endosomal trapping and lysosomal degradation.

Photothermal Nanomaterials: A Powerful Light-to-Heat Converter

All forms of energy follow the law of conservation of energy, by which they can be neither created nor destroyed. Light-to-heat conversion as a traditional yet constantly evolving means of converting light into thermal energy has been of enduring appeal to researchers and the public. With the continuous development of advanced nanotechnologies, a variety of photothermal nanomaterials have been endowed with excellent light harvesting and photothermal conversion capabilities for exploring fascinating and prospective applications. Herein we review the latest progresses on photothermal nanomaterials, with a focus on their underlying mechanisms as powerful light-to-heat converters. We present an extensive catalogue of nanostructured photothermal materials, including metallic/semiconductor structures, carbon materials, organic polymers, and two-dimensional materials. The proper material selection and rational structural design for improving the photothermal performance are then discussed. We also provide a representative overview of the latest techniques for probing photothermally generated heat at the nanoscale. We finally review the recent significant developments of photothermal applications and give a brief outlook on the current challenges and future directions of photothermal nanomaterials.

Nanomedicine Penetration to Tumor: Challenges, and Advanced Strategies to Tackle This Issue

Nanomedicine has been under investigation for several years to improve the efficiency of chemotherapeutics, having minimal pharmacological effects clinically. Ineffective tumor penetration is mediated by tumor environments, including limited vascular system, rising cancer cells, higher interstitial pressure, and extra-cellular matrix, among other things. Thus far, numerous methods to increase nanomedicine access to tumors have been described, including the manipulation of tumor micro-environments and the improvement of nanomedicine characteristics; however, such outdated approaches still have shortcomings. Multi-functional convertible nanocarriers have recently been developed as an innovative nanomedicine generation with excellent tumor infiltration abilities, such as tumor-penetrating peptide-mediated transcellular transport. The developments and limitations of nanomedicines, as well as expectations for better outcomes of tumor penetration, are discussed in this review.

The Janus of Protein Corona on nanoparticles for tumor targeting, immunotherapy and diagnosis

The therapeutics based on nanoparticles (NPs) are considered as the promising strategy for tumor detection and treatment. However, one of the most challenges is the adsorption of biomolecules on NPs after their exposition to biological medium, leading unpredictable in vivo behaviors. The interactions caused by protein corona (PC) will influence the biological fate of NPs in either negative or positive ways, including (i) blood circulation, accumulation and penetration of NPs at targeting sites, and further cellular uptake in tumor targeting delivery; (ii) interactions between NPs and receptors on immune cells for immunotherapy. Besides, PC on NPs could be utilized as new biomarker in tumor diagnosis by identifying the minor change of protein concentration led by tumor growth and invasion in blood. Herein, the mechanisms of these PC-mediated effects will be introduced. Moreover, the recent advances about the strategies will be reviewed to reduce negative effects caused by PC and/or utilize positive effects of PC on tumor targeting, immunotherapy and diagnosis, aiming to provide a reasonable perspective to recognize PC with their applications.

High Directional Water Transport Graphene Oxide Biphilic Stack

Understanding the nature of water transport in nanoscale is of high importance. Graphene properties such as mass flow rate, stability, filtration efficiency, and selectivity have been studied in various fields. It is a widely held view that the hydrophilicity of graphene oxide enhances the water transport properties. In this study, it is shown that despite this belief, a combination of graphene and graphene oxide can yield superior transport properties including high mass flow rate and directionality. Firstly, different membrane characteristics such as the smallest pore diameter for water molecules sieving and mass flow rate have been evaluated. Furthermore, a combination of graphene and graphene oxide, a biphilic stack of hydrophobic and hydrophilic layers, are used to evaluate the mass flow rates and results are compared with that of normal graphene oxide laminates. The proposed structure acts like a water diode i.e. conduct water molecules in a desired direction and increases the mass flow rate several times. The effect of interatomic potential, oxidation level and charge, and the spacing between layers on both mass flow rate and directionality are examined. It is found that an optimized structure conducts water in a desired direction and increases the mass flow rate up to 10 times for the small interlayer distance of 7 Å compared to the normal graphene oxide laminates. The given structures can be used in a wide range of filtration applications where selective water sieving with high mass flow rate is desired.

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.

A potentially valuable nano graphene oxide/USPIO tumor diagnosis and treatment system

Due to increased requirements for precision cancer treatment, cancer chemotherapy and combination therapies have gradually developed in the direction of diagnosis and treatment integration. In this study, a non-toxic nano carrier that demonstrates integrated MRI signal enhancing performance, as well as better chemotherapy and photothermal conversion performance, was prepared and characterized. Furthermore, the carrier was used to construct an integrated system of tumor diagnosis and treatment. Our in vitro studies showed that this system has a considerable inhibition effect on tumor cells during the treatment of chemotherapy when combined with PTT, and in vivo studies showed that the system could improve the MRI signal of the tumor site with application of a safe dosage. Thus, this system based on NGO/USPIO has the potential to be a multi-functional nano drug delivery system integrating diagnosis and treatment benefits and applications that are worthy of further research.

Sponge particulates for biomedical applications: Biofunctionalization, multi-drug shielding, and theranostic applications

Sponge particulates have attracted enormous attention in biomedical applications for superior properties, including large porosity, elastic deformation, capillary action, and three-dimensional (3D) reaction environment. Especially, the tiny porous structures make sponge particulates a promising platform for drug delivery, tissue engineering, anti-infection, and wound healing by providing abundant reservoirs of broad surface and internal network for cargo shielding and shuttling. To control the sponge-like morphology and improve the diversity of drug loading, some optimized preparation techniques of sponge particulates have been developed, contributing to the simplified preparation process and improved production reproducibility. Bio-functionalized strategies, including target modification, cell membrane camouflage, and hydrogel of sponge particulates have been applied to modulate the properties, improve the performance, and extend the applications. In this review, we highlight the unique physical properties and functions, current manufacturing techniques, and an overview of spongy particulates in biomedical applications, especially in inhibition of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infectivity. Moreover, the current challenges and prospects of sponge particulates are discussed rationally, providing an insight into developing vibrant fields of sponge particulates-based biomedicine.

Assessing the Combinatorial Chemo-Photothermal Therapy Mediated by Sulfobetaine Methacrylate-Functionalized Nanoparticles in 2D and 3D In Vitro Cancer Models

Combinatorial cancer therapies mediated by nanomaterials can potentially overcome the limitations of conventional treatments. These therapies are generally investigated using 2D in vitro cancer models, leading to an inaccurate screening. Recently, 3D in vitro spheroids have emerged in the preclinical testing stage of nanomedicines due to their ability to mimic key features of the in vivo solid tumors. Investigate the chemo-photothermal therapy mediated by Doxorubicin and IR780 loaded sulfobetaine methacrylate functionalized nanoparticles, for the first time, using monolayers of cancer cells and spheroids. In the 2D cancer models, the nanomaterials' mediated photothermal therapy, chemotherapy, and chemo-photothermal therapy reduced cancer cells' viability to about 58%, 29%, and 1%, respectively. Interestingly, when the nanomaterials' mediated photothermal therapy is tested on 3D spheroids, no cytotoxic effect is noticed. In contrast, the nanostructures' induced chemotherapy decreased spheroids' viability to 42%. On the other hand, nanomaterials' mediated chemo-photothermal therapy diminished spheroids' viability to 16%, being the most promising therapeutic modality. These results demonstrate the importance of using 3D spheroids during the in vitro screening of single/combinatorial therapies mediated by nanomaterials.

A Redox-Responsive, In-Situ Polymerized Polyplatinum(IV)-Coated Gold Nanorod as An Amplifier of Tumor Accumulation for Enhanced Thermo-Chemotherapy

It remains a major challenge to develop an effective therapeutic system based on gold nanorods (GNRs) for cancer therapy. Herein, we developed a redox-responsive, in-situ polymerized polyplatinum(IV)-coated gold nanorod (GNR@polyPt(IV)) with coupling of the near-infrared (NIR)-induced hyperthermal effect and redox-triggered drug release in one therapeutic platform as an amplifier of tumor accumulation through mild hyperthermia for enhanced synergistical thermo-chemotherapy. After in-situ polymerized with 2-methacryloyloxy ethyl phosphorylcholine (MPC) and Pt(IV) complex-based prodrug monomer (PPM) onto the surface of GNRs, the nanosized GNR@polyPt(IV) exhibited the advantages of high drug encapsulation efficiency, triggered drug release, and reduced side effect. As demonstrated by thermal imaging and photoacoustic imaging in vitro and in vivo, this GNR@polyPt(IV) exhibited an excellent NIR-associated hyperthermal effect and outstanding capacity of tumor accumulation. Importantly, under a mild hyperthermia process, the vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1α (HIF-1α) were upregulation, resulting in angiogenic vessel around the tumor. Combination with accelerated blood flow and angiogenesis by mild hyperthermia, a dramatic increase of drug accumulation in tumor could be realized after systematic administration. As a result, this amplification fashion of tumor accumulation would contribute the GNR@polyPt(IV) to inhibit tumor progression effectively. Such a facile and simple methodology for enhanced therapeutic effect based on GNRs holds great promises for cancer therapy with further development.

Lactoferrin, a multi-functional glycoprotein: Active therapeutic, drug nanocarrier & targeting ligand

Recent progress in protein-based nanomedicine, inspired by the success of Abraxane® albumin-paclitaxel nanoparticles, have resulted in novel therapeutics used for treatment of challenging diseases like cancer and viral infections. However, absence of specific drug targeting, poor pharmacokinetics, premature drug release, and off-target toxicity are still formidable challenges in the clinic. Therefore, alternative protein-based nanomedicines were developed to overcome those challenges. In this regard, lactoferrin (Lf), a glycoprotein of transferrin family, offers a promising biodegradable well tolerated material that could be exploited both as an active therapeutic and drug nanocarrier. This review highlights the major pharmacological actions of Lf including anti-cancer, antiviral, and immunomodulatory actions. Delivery technologies of Lf to improve its pries and enhance its efficacy were also reviewed. Moreover, different nano-engineering strategies used for fabrication of drug-loaded Lf nanocarriers were discussed. In addition, the use of Lf for functionalization of drug nanocarriers with emphasis on tumor-targeted drug delivery was illustrated. Besides its wide application in oncology nano-therapeutics, we discussed the recent advances of Lf-based nanocarriers as efficient platforms for delivery of anti-parkinsonian, anti-Alzheimer, anti-viral drugs, immunomodulatory and bone engineering applications.

Graphene oxide suppresses the growth and malignancy of glioblastoma stem cell-like spheroids via epigenetic mechanisms

Background

Glioblastoma stem-like cells (GSCs) are hypothesized to contribute to self-renewal and therapeutic resistance in glioblastoma multiforme (GBM) tumors. Constituting only a small percentage of cancer cells, GSCs possess “stem-like”, tumor-initiating properties and display resistance to irradiation and chemotherapy. Thus, novel approaches that can be used to suppress GSCs are urgently needed. A new carbon material—graphene oxide (GO), has been reported to show potential for use in tumor therapy. However, the exact effect of GO on GSCs and the inherent mechanism underlying its action are not clear. In this study, we aimed to investigate the usefulness of GO to inhibit the growth and promote the differentiation of GSCs, so as to suppress the malignancy of GBM.

Methods

In vitro effects of GO on sphere-forming ability, cell proliferation and differentiation were evaluated in U87, U251 GSCs and primary GSCs. The changes in cell cycle and the level of epigenetic modification H3K27me3 were examined. GO was also tested in vivo against U87 GSCs in mouse subcutaneous xenograft models by evaluating tumor growth and histological features.

Results

We cultured GSCs to explore the effect of GO and the underlying mechanism of its action. We found, for the first time, that GO triggers the inhibition of cell proliferation and induces apoptotic cell death in GSCs. Moreover, GO could promote the differentiation of GSCs by decreasing the expression of stem cell markers (SOX2 and CD133) and increasing the expression of differentiation-related markers (GFAP and β-III tubulin). Mechanistically, we found that GO had a striking effect on GSCs by inducing cell cycle arrest and epigenetic regulation. GO decreased H3K27me3 levels, which are regulated by EZH2 and associated with transcriptional silencing, in the promoters of the differentiation-related genes GFAP and β-III tubulin, thereby enhancing GSC differentiation. In addition, compared with untreated GSCs, GO-treated GSCs that were injected into nude mice exhibited decreased tumor growth in vivo.

Conclusion

These results suggested that GO could promote differentiation and reduce malignancy in GSCs via an unanticipated epigenetic mechanism, which further demonstrated that GO is a potent anti-GBM agent that could be useful for future clinical applications.

Rabies virus glycoprotein-amplified hierarchical targeted hybrids capable of magneto-electric penetration delivery to orthotopic brain tumor

Compact nanohybrids can potentially unite various therapeutic features and reduce side effects for precise cancer therapy. However, the poor accumulation and limited tumor penetration of drugs at the tumor impede the manifestation of nanomedicine. We developed a rabies virus glycoprotein (RVG)-amplified hierarchical targeted hybrid that acts as a stealthy and magnetolytic carrier that transports dual tumor-penetrating agents incorporating two drugs (boron-doped graphene quantum dots (B-GQDs)/doxorubicin and pH-responsive dendrimers (pH-Den)/palbociclib). The developed RVG-decorated hybrids (RVG-hybrids) enhance the accumulation of drugs at tumor by partially bypassing the BBB via spinal cord transportation and pH-induced aggregation of hierarchical targeting. The penetrated delivery of dual pH-Den and B-GQD drugs to deep tumors is actuated by magnetoelectric effect, which are able to generate electrons to achieve electrostatic repulsion and disassemble the hybrids into components of a few nanometers in size. The synergy of magnetoelectric drug penetration and chemotherapy was achieved by delivery of the B-GQDs and pH-Den to orthotopic tumors, which prolonged the host survival time. This RVG-amplified dual hierarchical delivery integrated with controlled and penetrated release from this hybrid improve the distribution of the therapeutic agents at the brain tumor for synergistic therapy, exhibiting potential for clinic use.

Applications of Surface Modification Technologies in Nanomedicine for Deep Tumor Penetration

The impermeable barrier of solid tumors due to the complexity of their components limits the treatment effect of nanomedicine and hinders its clinical translation. Several methods are available to increase the penetrability of nanomedicine, yet they are too complex to be effective, operational, or practical. Surface modification employs the characteristics of direct contact between multiphase surfaces to achieve the most direct and efficient penetration of solid tumors. Furthermore, their simple operation makes their use feasible. In this review, the latest surface modification strategies for the penetration of nanomedicine into solid tumors are summarized and classified into "bulldozer strategies" and "mouse strategies." Additionally, the evaluation methods, existing problems, and the development prospects of these technologies are discussed.

Dispersed graphene materials of biomedical interest and their toxicological consequences

Graphene is one-atom thick nanocarbon displaying a unique honeycomb structure and extensive conjugation. In addition to high surface area to mass ratio, it displays unique optical, thermal, electronic and mechanical properties. Atomic scale tunability of graphene has attracted immense research interest with a prospective utility in electronics, desalination, energy sectors, and beyond. Its intrinsic opto-thermal properties are appealing from the standpoint of multimodal drug delivery, imaging and biosensing applications. Hydrophobic basal plane of sheets can be efficiently loaded with aromatic molecules via non-specific forces. With intense biomedical interest, methods are evolving to produce defect-free and dispersion stable sheets. This review summarizes advancements in synthetic approaches and strategies of stabilizing graphene derivatives in aqueous medium. We have described the interaction of colloidal graphene with cellular and sub-cellular components, and subsequent physiological signaling. Finally, a systematic discussion is provided covering toxicological challenges and possible solutions on utilizing graphene formulations for high-end biomedical applications.

Bioinspired Polymeric-based Core-shell Smart Nano-systems

Smart nanosystems (SNs) have the potential to revolutionize drug delivery. Conventional drug delivery systems have poor drug-loading, early burst release, limited therapeutic effects, etc. Thus, to overcome these problems, researchers have taken advantage of the host-guest interactions as bioinspired nanosystems which can deliver nanocarriers more efficiently with the maximum drug loading capacity and improved therapeutic efficacy as well as bioavailability. SNs employ nanomaterials to form cage molecules by entrapping new nanocarriers called smart nanosystems in their cargo and design. The activities of SNs are based on responsive materials that interact with the stimuli either by changing their properties or conformational structures. The aptitude of living systems to respond to stimuli and process information has encouraged researchers to build up integrated nanosystems exhibiting similar function and therapeutic response. Various smart materials, including polymers, have been exhaustively employed in fabricating different stimuli-responsive nanosystems which can deliver bioactive molecules to a specific site for a certain period with minimal side effects. SNs have been widely explored to deliver diverse kinds of therapeutic agents ranging from bioactive compounds, genes, and biopharmaceuticals like proteins and peptides, to diagnostic imaging agents for biomedical applications. Nanotechnology-based different nanosystems are promising for health care issues. The advancement of SNs with physical science and engineering technology in synthesizing nanostructures and their physicochemical characterization should be exploited in medicine and healthcare for reducing mortality rate, morbidity, disease prevalence and general societal burden.

A Multifunctional Biodegradable Nanocomposite for Cancer Theranostics

Theranostic formulations, integrating both diagnostic and therapeutic functions into a single platform, hold great potential for precision medicines. In this work, a biodegradable theranostic based on hollow mesoporous organosilica nanoparticles (HMONs) is reported and explored for ultrasound/photoacoustic dual-modality imaging guided chemo-photothermal therapy of cancer. The HMONs prepared are endowed with glutathione-responsive biodegradation behavior by incorporating disulfide bonds into their framework. The nanoparticles are loaded with indocyanine green (ICG) and perfluoropentane (PFP). The former acts as a photothermal agent and the latter can generate bubbles for ultrasound imaging. A paclitaxel prodrug is developed to both serve as a redox-sensitive gatekeeper controlling ICG release from the HMON pores and a chemotherapeutic. ICG generates mild hyperthermia upon exposure to an 808 nm laser, and this in turn leads to a liquid-gas phase transition of PFP, resulting in the generation of bubbles which can be used for ultrasound imaging. The platform is found to have excellent properties for both ultrasound and photoacoustic imaging. In addition, both in vitro and in vivo results show that the nanoparticles provide potent synergistic chemo-photothermal therapy. The material developed in this work thus has great potential for exploitation in advanced cancer therapies.

Water-Responsive Hybrid Nanoparticles Codelivering ICG and DOX Effectively Treat Breast Cancer via Hyperthermia-aided DOX Functionality and Drug Penetration

Tumor growth and metastasis are the major causes of high mortality in breast cancer. In this study, a water-responsive phospholipid-calcium-carbonate hybrid nanoparticle (PL/ACC-DOX&ICG) surface modified with a phospholipid shell is designed and covered with a shielding polymer polyethylene glycol; this development is loaded with the photosensitizer indocyanine green (ICG) and the chemotherapeutic drug doxorubicin (DOX) for near-infrared (NIR) imaging and chemophotothermal combination therapy against breast cancer. PL/ACC-DOX&ICG exhibits satisfactory stability against various aqueous environments with minimal drug leakage and can readily decompose to facilitate quick drug release into cancer cells. In vivo biodistribution studies, PL/ACC-DOX&ICG demonstrated strong tumor-homing properties. Interestingly, the in vitro cellular uptake and intratumoral penetration depth of PL/ACC-DOX&ICG are significantly enhanced under NIR laser irradiation, owing to ICG-induced hyperthermia, which not only enhances cell permeability and fluidity but also disrupts the dense tumor extracellular matrix. Compared to chemotherapy or photothermal therapy alone, chemophotothermal combination therapy synergistically induces apoptosis and death in 4T1 cells. Moreover, compared with the phosphate buffer saline group, the combined treatment suppress primary tumor growth at a rate of approximately 94.88% and decrease the number of metastatic nodules by about 93.6%. Therefore, PL/ACC-DOX&ICG may be a promising nanoplatform for breast cancer treatment.

Photothermal therapy and photoacoustic imaging via nanotheranostics in fighting cancer

The nonradiative conversion of light energy into heat (photothermal therapy, PTT) or sound energy (photoacoustic imaging, PAI) has been intensively investigated for the treatment and diagnosis of cancer, respectively. By taking advantage of nanocarriers, both imaging and therapeutic functions together with enhanced tumour accumulation have been thoroughly studied to improve the pre-clinical efficiency of PAI and PTT. In this review, we first summarize the development of inorganic and organic nano photothermal transduction agents (PTAs) and strategies for improving the PTT outcomes, including applying appropriate laser dosage, guiding the treatment via imaging techniques, developing PTAs with absorption in the second NIR window, increasing photothermal conversion efficiency (PCE), and also increasing the accumulation of PTAs in tumours. Second, we introduce the advantages of combining PTT with other therapies in cancer treatment. Third, the emerging applications of PAI in cancer-related research are exemplified. Finally, the perspectives and challenges of PTT and PAI for combating cancer, especially regarding their clinical translation, are discussed. We believe that PTT and PAI having noteworthy features would become promising next-generation non-invasive cancer theranostic techniques and improve our ability to combat cancers.

Graphene-Based Smart Platforms for Combined Cancer Therapy

The extensive research of graphene and its derivatives in biomedical applications during the past few years has witnessed its significance in the field of nanomedicine. Starting from simple drug delivery systems, the application of graphene and its derivatives has been extended to a versatile platform of multiple therapeutic modalities, including photothermal therapy, photodynamic therapy, magnetic hyperthermia therapy, and sonodynamic therapy. In addition to monotherapy, graphene-based materials are widely applied in combined therapies for enhanced anticancer activity and reduced side effects. In particular, graphene-based materials are often designed and fabricated as "smart" platforms for stimuli-responsive nanocarriers, whose therapeutic effects can be activated by the tumor microenvironment, such as acidic pH and elevated glutathione (termed as "endogenous stimuli"), or light, magnetic, or ultrasonic stimuli (termed as "exogenous stimuli"). Herein, the recent advances of smart graphene platforms for combined therapy applications are presented, starting with the principle for the design of graphene-based smart platforms in combined therapy applications. Next, recent advances of combined therapies contributed by graphene-based materials, including chemotherapy-based, photothermal-therapy-based, and ultrasound-therapy-based synergistic therapy, are outlined. In addition, current challenges and future prospects regarding this promising field are discussed.

Graphene Quantum Dots-Mediated Theranostic Penetrative Delivery of Drug and Photolytics in Deep Tumors by Targeted Biomimetic Nanosponges

Dual-targeted delivery of drugs and energy by nanohybrids can potentially alleviate side effects and improve the unique features required for precision medicine. To realize this aim, however, the hybrids which are often rapidly removed from circulation and the piled up tumors periphery near the blood vessels must address the difficulties in low blood half-lives and tumor penetration. In this study, a sponge-inspired carbon composites-supported red blood cell (RBC) membrane that doubles as a stealth agent and photolytic carrier that transports tumor-penetrative agents (graphene quantum dots and docetaxel (GQD-D)) and heat with irradiation was developed. The RBC-membrane enveloped nanosponge (RBC@NS) integrated to a targeted protein that accumulates in tumor spheroids via high lateral bilayer fluidity exhibits an 8-fold increase in accumulation compared to the NS. Penetrative delivery of GQDs to tumor sites is actuated by near-infrared irradiation through a one-atom-thick structure, facilitating penetration and drug delivery deep into the tumor tissue. The synergy of chemotherapy and photolytic effects was delivered by the theranostic GQDs deep into tumors, which effectively damaged and inhibited the tumor in 21 days when treated with a single irradiation. This targeted RBC@GQD-D/NS with the capabilities of enhanced tumor targeting, NIR-induced drug penetration into tumors, and thermal ablation for photolytic therapy promotes tumor suppression and exhibits potential for other biomedical applications.

Staphylococcus aureus-mimetic control of antibody orientation on nanoparticles

We designed a bacterio-mimetic nanoparticle that can noncovalently control the orientation of attached antibodies. Liposomes with Fc-binding peptide (FcBP), formulated using FcBP-conjugated PEGylated lipid, were used as model nanoparticles. Compared with control nanoparticles surface-modified with antibody covalently attached via maleimide functional groups (Mal-NPs), FcBP-capped nanoparticles (FcBP-NPs) exhibited greater binding affinity to the target protein. Human epidermal growth factor receptor 2 (HER2)-specific antibody-modified FcBP-NPs (HER2/FcBP-NPs) showed 5.3-fold higher binding affinity to HER2 than isotype IgG antibody-modified NPs, and 2.6-fold higher affinity compared with anti-HER2 antibody-conjugated Mal-NPs. Cellular uptake of HER2/FcBP-NPs in HER2-positive cells was significantly higher than that of other formulations. The biodistribution of HER2/FcBP-NPs was higher than that of antibody-conjugated NPs in HER2-positive tumor tissues, but not in HER2-negative tumors. Our findings suggest the potential of bacteriomimetic nanoparticles for controlling the orientation of antibody attachment. These nanoparticles may have diverse applications in nanomedicine, including drug delivery, molecular imaging, and diagnosis.

Functional Nanoparticles for Tumor Penetration of Therapeutics

Theranostic nanoparticles recently received great interest for uniting unique functions to amplify therapeutic efficacy and reduce side effects. Despite the enhanced permeability and retention (EPR) effect, which amplifies the accumulation of nanoparticles at the site of a tumor, tumor heterogeneity caused by the dense extracellular matrix of growing cancer cells and the interstitial fluid pressure from abnormal angiogenesis in the tumor inhibit drug/particle penetration, leading to inhomogeneous and limited treatments. Therefore, nanoparticles for penetrated delivery should be designed with different strategies to enhance efficacy. Many strategies were developed to overcome the obstacles in cancer therapy, and they can be divided into three main parts: size changeability, ligand functionalization, and modulation of the tumor microenvironment. This review summarizes the results of ameliorated tumor penetration approaches and amplified therapeutic efficacy in nanomedicines. As the references reveal, further study needs to be conducted with comprehensive strategies with broad applicability and potential translational development.

Simultaneous drug delivery and cellular imaging using graphene oxide

Graphene oxide (GO), a derivative of graphene, and its related nanomaterials have attracted much attention in recent years due to the excellent biocompatibility and large surface area of GO with abundant oxygen functional groups, which further enable it to serve as a nano-bio interface. Herein, we demonstrate the induction of blue fluorescence in GO suspensions via a mild thermal annealing procedure. Additionally, this procedure preserves the oxygen functional groups on the graphene plane which enables the conjugation of cancer drugs without obvious cytotoxicity. Consequently, we demonstrate the capability of GO to simultaneously play the dual-role of a: (i) cellular imaging agent and (ii) drug delivery agent in CT26 cancer cells without the need for additional fluorescent protein labeling. Our method offers a simple, controllable strategy to tune and enhance the fluorescence property of GO, which shows potential for biomedical applications and fundamental studies.

Therapeutics incorporating blood constituents

Blood deficiency and dysfunctionality can result in adverse events, which can primarily be treated by transfusion of blood or the re-introduction of properly functioning sub-components. Blood constituents can be engineered on the sub-cellular (i.e., DNA recombinant technology) and cellular level (i.e., cellular hitchhiking for drug delivery) for supplementing and enhancing therapeutic efficacy, in addition to rectifying dysfunctioning mechanisms (i.e., clotting). Herein, we report the progress of blood-based therapeutics, with an emphasis on recent applications of blood transfusion, blood cell-based therapies and biomimetic carriers. Clinically translated technologies and commercial products of blood-based therapeutics are subsequently highlighted and perspectives on challenges and future prospects are discussed.

STATEMENT OF SIGNIFICANCE

Blood-based therapeutics is a burgeoning field and has advanced considerably in recent years. Blood and its constituents, with and without modification (i.e., combinatorial), have been utilized in a broad spectrum of pre-clinical and clinically-translated treatments. This review article summarizes the most up-to-date progress of blood-based therapeutics in the following contexts: synthetic blood substitutes, acellular/non-recombinant therapies, cell-based therapies, and therapeutic sub-components. The article subsequently discusses clinically-translated technologies and future prospects thereof.

Dual-drug nanomedicine with hydrophilic F127-modified magnetic nanocarriers assembled in amphiphilic gelatin for enhanced penetration and drug delivery in deep tumor tissue

Introduction

Deep penetration of large-sized drug nanocarriers into tumors is important to improve the efficacy of tumor therapy.

Methods

In this study, we developed a size-changeable “Trojan Horse” nanocarrier (THNC) composed of paclitaxel (PTX)-loaded Greek soldiers (GSs; ~20 nm) assembled in an amphiphilic gelatin matrix with hydrophilic losartan (LST) added.

Results

With amphiphilic gelatin matrix cleavage by matrix metalloproteinase-2, LST showed fast release of up to 60% accumulated drug at 6 h, but a slow release kinetic (~20%) was detected in the PTX from the GSs, indicating that THNCs enable controllable release of LST and PTX drugs for penetration into the tumor tissue. The in vitro cell viability in a 3D tumor spheroid model indicated that the PTX-loaded GSs liberated from THNCs showed deeper penetration as well as higher cytotoxicity, reducing a tumor spheroid to half its original size and collapsing the structure of the tumor microenvironment.

Conclusion

The results demonstrate that the THNCs with controlled drug release and deep penetration of magnetic GSs show great potential for cancer therapy.

Advances on graphene-based nanomaterials for biomedical applications

Graphene-based nanomaterials, such as graphene oxide and reduced graphene oxide, have been attracting increasing attention in the field of biology and biomedicine over the past few years. Incorporation of these novel materials with drug, gene, photosensitizer and other cargos to construct novel delivery systems has witnessed rapid advance on the basis of their large surface area, distinct surface properties, excellent biocompatibility and pH sensitivity. Moreover, the inherent photothermal effect of these appealing materials enables them with the ability of killing targeting cells via a physical mechanism. Recently, more attentions have been attached to tissue engineering, including bone, neural, cardiac, cartilage, musculoskeletal, and skin/adipose tissue engineering, due to the outstanding mechanical strength, stiffness, electrical conductivity, various two-dimensional (2D) and three-dimensional (3D) morphologies of graphene-based nanomaterials. Herein, emerging applications of these nanomaterials in bio-imaging, drug/gene delivery, phototherapy, multimodality therapy and tissue engineering were comprehensively reviewed. Inevitably, the burgeon of this kind of novel materials leads to the endeavor to consider their safety so that this issue has been deeply discussed and summarized in our review. We hope that this review offers an overall understanding of these nanomaterials for later in-depth investigations.

Strategies to improve tumor penetration of nanomedicines through nanoparticle design

Nanoparticles (NPs) have emerged as an effective means to deliver therapeutic drugs for cancer treatment, as they can preferentially accumulate at tumor site through the enhanced permeability and retention effect. Various forms of NPs including liposomes, polymeric micelles, and inorganic particles have been used for therapeutic applications. However, the therapeutic benefits of nanomedicines are suboptimal. Although many possible reasons may account for the compromised therapeutic efficacy, the inefficient tumor penetration can be a vital obstacle. Tumor develops characteristic pathological environment, such as abnormal vasculature, elevated interstitial fluid pressure, and dense extracellular matrix, which intrinsically hinder the transport of nanomedicines in the tumor parenchyma. The physicochemical properties of the NPs such as size, shape, and surface charge have profound effect on tumor penetration. In this review, we will highlight the factors that affect the transport of NPs in solid tumor, and then elaborate on designing strategies to improve NPs' penetration and uniform distribution inside the tumor interstitium. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Biodegradable Hollow Mesoporous Organosilica Nanotheranostics for Mild Hyperthermia-Induced Bubble-Enhanced Oxygen-Sensitized Radiotherapy

Alleviation of tumor hypoxia has been the premise for improving the effectiveness of radiotherapy, which hinges upon the advanced delivery and rapid release of oxygen within the tumor region. Herein, we propose a "bubble-enhanced oxygen diffusion" strategy to achieve whole tumor oxygenation for significant radiation enhancement based on the "bystander effect". Toward this end, sub-50 nm CuS-modified and ⁶⁴Cu-labeled hollow mesoporous organosilica nanoparticles were constructed for tumor-specific delivery of O₂-saturated perfluoropentane (PFP). Through the aid of PFP gasification arising from NIR laser-triggered mild hyperthermia, simultaneous PET/PA/US multimodality imaging and rapid oxygen diffusion across the tumor can be achieved for remarkable hypoxic radiosensitization. Furthermore, the multifunctional oxygen-carrying nanotheranostics also allow for other oxygen-dependent treatments, thus greatly advancing the development of bubble-enhanced synergistic therapy platforms.

Polymer-Based Nanocarriers for Co-Delivery and Combination of Diverse Therapies against Cancers

Cancer gives rise to an enormous number of deaths worldwide nowadays. Therefore, it is in urgent need to develop new therapies, among which combined therapies including photothermal therapy (PTT) and chemotherapy (CHT) using polymer-based nanocarriers have attracted enormous interest due to the significantly enhanced efficacy and great progress has been made so far. The preparation of such nanocarriers is a comprehensive task involving the cooperation of nanomaterial science and biomedicine science. In this review, we try to introduce and analyze the structure, preparation and synergistic therapeutic effect of various polymer-based nanocarriers composed of anti-tumor drugs, nano-sized photothermal materials and other possible parts. Our effort may bring benefit to future exploration and potential applications of similar nanocarriers.

Functionalized graphene sheets for intracellular controlled release of therapeutic agents

Since therapeutic agents target specific compartments inside the cells, their efficiency depends on their intracellular release from drug delivery systems (DDS). However, control over the intracellular release of therapeutic agents is a challenging issue and can only be achieved by governing their interactions with the DDS. In this work, polyglycerol amine- and polyglycerol sulfate-functionalized graphene sheets as positively and negatively charged 2D nanomaterials with 150 nm lateral size were used to deliver and control the release of doxorubicin (DOX) inside cells. A pH-sensitive dye was conjugated onto the surfaces of graphene sheets and used as an antenna to obtain specific signals from the acidic cell compartments. It was found that both positively and negatively charged graphene sheets undergo similar acidification processes after cellular uptake. Nevertheless, the intracellular drug release of these DOX-loaded nanomaterials was distinctly different. As an overall effect of the π-π stacking and electrostatic interactions, the release of DOX from the positively charged graphene sheets was much faster than that from their analogs with a negative surface charge. Therefore, therapeutic efficiency in the first case was much higher than that in the latter. Based on our findings, the intracellular release of drugs from the surfaces of graphene sheets can be finely tuned by manipulating their functionalities, which is of great importance in the designing of the future graphene-based nanomedicines.

Enhancing Tumor Penetration of Nanomedicines

Tumor-targeted nanomedicines have been extensively applied to alter the drawbacks and enhance the efficacy of chemotherapeutics. Despite the large number of preclinical nanomedicine studies showing initial success, their therapeutic benefit in the clinic has been rather modest, which is partially due to the inefficient tumor penetration caused by the tumor microenvironment (high density of cells and extracellular matrix, increased interstitial fluid pressure). Furthermore, tumor penetration of nanomedicines is significantly influenced by physicochemical characteristics, such as size, surface chemistry, and shape. The effect of size on tumor penetration has been exploited to design nanomedicines with switchable size to tackle this challenge. Moreover, several pharmacological and physical approaches have been developed to enhance the tumor penetration of nanomedicines, by penetration-promoting ligands, intratumoral drug release, and modulating the tumor microenvironment and vasculature. Overall, these efforts have resulted in nanomedicines with better tumor penetration properties and with enhanced therapeutic efficacy. Future research should be directed to penetration-promoting strategies with broad applicability and with high translational potential.

Multifunctional PS@CS@Au–Fe3O4–FA nanocomposites for CT, MR and fluorescence imaging guided targeted-photothermal therapy of cancer cells

Multifunctional theranostic PS@CS@Au–Fe₃O₄–FA/ICG nanocomposites for MR, CT and fluorescence multiple-modal imaging-guided targeted photothermal therapy were fabricated, and they might be a promising theranostic nanoplatform for tumor diagnostics and treatment.