Polyethylene glycol modified ORMOSIL theranostic nanoparticles for triggered doxorubicin release and deep drug delivery into ovarian cancer spheroids

Application progress of nanomaterials in the treatment of prostate cancer

Prostate cancer is one of the most common malignant tumors in men, which seriously threatens the survival and quality of life of patients. At present, there are serious limitations in the treatment of prostate cancer, such as drug tolerance, drug resistance and easy recurrence. Sonodynamic therapy and chemodynamic therapy are two emerging tumor treatment methods, which activate specific drugs or sonosensitizers through sound waves or chemicals to produce reactive oxygen species and kill tumor cells. Nanomaterials are a kind of nanoscale materials with many excellent physical properties such as high targeting, drug release regulation and therapeutic monitoring. Sonodynamic therapy and chemodynamic therapy combined with the application of nanomaterials can improve the therapeutic effect of prostate cancer, reduce side effects and enhance tumor immune response. This article reviews the application progress of nanomaterials in the treatment of prostate cancer, especially the mechanism, advantages and challenges of nanomaterials in sonodynamic therapy and chemodynamic therapy, which provides new ideas and prospects for research in this field.

Advances in the study of spheroids as versatile models to evaluate biological interactions of inorganic nanoparticles

Spheroids are in vitro three-dimensional multicellular microstructures able to mimic the biological microenvironment, including the complexity of tumor architecture. Therefore, results closer to those expected for in vivo organisms can be reached using spheroids compared to the cell culture monolayer model. Inorganic nanoparticles (NPs) have also been playing relevant roles in the comprehension of biological processes. Moreover, they have been probed as novel diagnostic and therapeutical nanosystems. In this context, in this review, we present applications, published in the last five years, which show that spheroids can be versatile models to study and evaluate biological interactions involving inorganic NPs. Applications of spheroids associated with (i) basic studies to assess the penetration profile of nanostructures, (ii) the evaluation of NP toxicity, and (iii) NP-based therapeutical approaches are described. Fundamentals of spheroids and their formation methods are also included. We hope that this review can be a reference and guide future investigations related to this interesting three-dimensional biological model, favoring advances to Nanobiotechnology.

Bioactive injectable hydrogels for on demand molecule/cell delivery and for tissue regeneration in the central nervous system

Currently there are no potential curative therapies that can improve the central nervous system (CNS) regeneration after traumatic injuries or diseases. Indeed, the regeneration of CNS is greatly impaired by limited drug penetration across the blood brain barrier (BBB), poor drug targeting, deficient progenitor neural cells and limited proliferation of mature neural cells. To overcome these limitations, bioengineered injectable hydrogels in combination with drug and cell therapy have been proposed to mimic the complexity of the CNS microenvironment and architecture. Additionally, to enhance relevant CNS regeneration, proper biophysical and biochemical cues are needed. Recently, great efforts have been devoted to tailor stimuli-responsive hydrogels as novel carrier systems which are able to guide neural tissue regeneration. This review provides an extensive overview on the most promising injectable hydrogels for neural tissue engineering. A special emphasis is made to highlight the ability of these hydrogels to deliver bioactive compounds/cells upon the exposure to internal and external stimuli. Bioactive injectable hydrogels have a broad application in central nervous system's (CNS) regeneration. This review gives an overview of the latest pioneering approaches in CNS recovery using stimuli-responsive hydrogels for several neurodegenerative disorders. STATEMENT OF SIGNIFICANCE: This review summarizes the latest innovations on bioactive injectable hydrogels, focusing on tailoring internal/external stimuli-responsive hydrogels for the new injectable systems design, able to guide neural tissue response. The purpose is to highlight the advantages and the limitations of thermo-responsive, photo responsive, magnetic responsive, electric responsive, ultrasound responsive and enzymes-triggered injectable hydrogels in developing customizable neurotherapies. We believe that this comprehensive review will help in identifying the strengths and gaps in the existing literature and to further support the use of injectable hydrogels in stimulating CNS regeneration.

Computational model of silica nanoparticle penetration into tumor spheroids: Effects of methoxy and carboxy PEG surface functionalization and hyperthermia

Drug delivery to tumors suffers from poor solubility, specificity, diffusion through the tumor micro-environment and nonoptimal interactions with components of the extracellular matrix and cell surface receptors. Nanoparticles and drug-polymer complexes address many of these problems. However, large size exasperates the problem of slow diffusion through the tumor. Three-dimensional tumor spheroids are good models to evaluate approaches to mitigate these difficulties and aid in design strategies to improve the delivery of drugs to treat cancer effectively. Diffusion of drug carriers is highly dependent on cell uptake rate parameters (association/dissociation) and temperature. Hyperthermia increases molecular transport and is known to act synergistically with chemotherapy to improve treatment. This study presents a new inverse estimation approach based on Bayesian probability for estimating nanoparticle cell uptake rates from experiments. The parameters were combined with a finite element computational model of nanoparticle transport under hyperthermia conditions to explore its effect on tumor porosity, diffusion and particle binding (association and dissociation) at cell surfaces. Carboxy-PEG-silane (cPEGSi) nanoparticles showed higher cell uptake compared to methoxy-PEG-silane (mPEGSi) nanoparticles. Simulations were consistent with experimental results from Skov-3 ovarian cancer spheroids. Amorphous silica (cPEGSi) nanoparticles (58 nm) concentrated at the periphery of the tumor spheroids at 37°C but mild hyperthermia (43°C) increased nanoparticle penetration. Thus, hyperthermia may enhance cancer treatment by improving blood delivery to tumors, enhancing extravasation and penetration into tumors, trigger release of drug from the carrier at the tumor site and possibly lead to synergistic anti-cancer activity with the drug.

The importance of spheroids in analyzing nanomedicine efficacy

The use of nanomedicines for cancer treatment holds a great potential due to their improved efficacy and safety. During the nanomedicine preclinical in vitro evaluation stage, these are mainly tested on cell culture monolayers. However, these 2D models are an unrealistic representation of the in vivo tumors, leading to an inaccurate screening of the candidate formulations. To address this problem, spheroids are emerging as an additional tool to validate the efficacy of new therapeutics due to the ability of these 3D in vitro cancer models to mimic the key features displayed by in vivo solid tumors. In this review, the application of spheroids for the evaluation of nanomedicines' physicochemical properties and therapeutic efficacy is discussed.

Toxicity of Carbon Nanotubes as Anti-Tumor Drug Carriers

Nanoparticle drug formulations have enormous application prospects owing to achievement of targeted and sustained release drug delivery, improvement in drug solubility and reduction of adverse drug reactions. Recently, a variety of efficient drug nanometer carriers have been developed, among which carbon nanotubes (CNT) have been increasingly utilized in the field of cancer therapy. However, these nanotubes exert various toxic effects on the body due to their unique physical and chemical properties. CNT-induced toxicity is related to surface modification, degree of aggregation in vivo, and nanoparticle concentration. This review has focused on the potential toxic effects of CNTs utilized as anti-tumor drug carriers. The main modes by which CNTs enter target sites, the toxicity expressive types and the factors affecting toxicity are discussed.

Nano-carriers for targeted delivery and biomedical imaging enhancement

Theranostic approaches using nanotechnology have been a hot research area for the past decade. All nano drug delivery techniques and architectures have some limitations, as do diagnostic nano-approaches. Thus, combining nano drug delivery strategies with diagnostic techniques using nanoparticles for improving imaging modalities has been the key to fill up those gaps. In the past decade, lots of approaches have been made with different combinations of biomaterials fabricated/synthesized to nanostructures with modified surface functionalization to improve their overall theranostic properties. This article summarizes recent research works based on the biomaterials used for fabricating these nanostructures. Their combinations with other biomaterials have been demonstrated with their overall advantages and limitations.

Current and novel polymeric biomaterials for neural tissue engineering

The nervous system is a crucial component of the body and damages to this system, either by of injury or disease, can result in serious or potentially lethal consequences. Restoring the damaged nervous system is a great challenge due to the complex physiology system and limited regenerative capacity.Polymers, either synthetic or natural in origin, have been extensively evaluated as a solution for restoring functions in damaged neural tissues. Polymers offer a wide range of versatility, in particular regarding shape and mechanical characteristics, and their biocompatibility is unmatched by other biomaterials, such as metals and ceramics. Several studies have shown that polymers can be shaped into suitable support structures, including nerve conduits, scaffolds, and electrospun matrices, capable of improving the regeneration of damaged neural tissues. In general, natural polymers offer the advantage of better biocompatibility and bioactivity, while synthetic or non-natural polymers have better mechanical properties and structural stability. Often, combinations of the two allow for the development of polymeric conduits able to mimic the native physiological environment of healthy neural tissues and, consequently, regulate cell behaviour and support the regeneration of injured nervous tissues.Currently, most of neural tissue engineering applications are in pre-clinical study, in particular for use in the central nervous system, however collagen polymer conduits aimed at regeneration of peripheral nerves have already been successfully tested in clinical trials.This review highlights different types of natural and synthetic polymers used in neural tissue engineering and their advantages and disadvantages for neural regeneration.

Target challenging-cancer drug delivery to gastric cancer tissues with a fucose graft epigallocatechin-3-gallate-gold particles nanocomposite approach

Inhibiting component of therapy with (-)-epigallocatechin-3-gallate (EGCG) is low bioavailability of fresh tea polyphenols that outcome from insecurity under stomach related circumstances, insufficient transcellular transport. As needs are, fucose- carboxymethyl chitosan (FU-CMC) graft EGCG with gold nanoparticles (GNPs) (FU-CMC-EGCG-GNPs) nanocomposites were prepared and managed peritumorally to assess their anticancer action. The physicochemical properties of as-prepared nanocomposite were evaluated by FTIR spectroscopy, UV-visible absorption spectra, XRD, FESEM-EDX and HRTEM-SAD. Additionally, the viability and cell uptake assays revealed that the as-prepared nanocomposite successfully repressed the propagation of gastric tumor cells. In vivo anticancer treatment of FU-CMC-EGCG-GNPs nanocomposites showed more anticancer action contrasted with pure EGCG. Immuno-histological investigations established a superior numeral of apoptotic tissues in the as-prepared FU-CMC-EGCG-GNPs nanocomposites contrasted with pure EGCG. Overall, the as-prepared FU-CMC-EGCG-GNPs nanocomposite affords a proficient medicine delivery stage for chemotherapy.