Mesoporous silica nanoparticles (MSNs)-based organic/inorganic hybrid nanocarriers loading 5-Fluorouracil for the treatment of colon cancer with improved anticancer efficacy

Recent development of micro-nano carriers for oral antineoplastic drug delivery

Chemotherapy is widely recognized as a highly efficacious modality for cancer treatment, involving the administration of chemotherapeutic agents to target and eradicate tumor cells. Currently, oral administration stands as the prevailing and widely utilized method of delivering chemotherapy drugs. However, the majority of anti-tumor medications exhibit limited solubility and permeability, and poor stability in harsh gastrointestinal environments, thereby impeding their therapeutic efficacy for chemotherapy. Therefore, more and more micro-nano drug delivery carriers have been developed and used to effectively deliver anti-cancer drugs, which can overcome physiological barriers, facilitate oral administration, and ultimately improve drug efficacy. In this paper, we first discuss the effects of various biological barriers on micro-nano drug carriers and oral administration approach. Then, the development of micro-nano drug carriers based on various biomedical components, such as micelles, dendrimers, hydrogels, liposomes, inorganic nanoparticles, etc. were introduced. Finally, the current dilemma and the potential of oral drug delivery for clinical treatment were discussed. The primary objective of this review is to introduce various oral delivery methods and serve as a point of reference for the advancement of novel oral delivery carriers, with the ultimate goal of informing the development of future clinical applications.

Exploring the Therapeutic Potential of 5-Fluorouracil-Loaded Calcium Carbonate Nanoparticles Combined with Natural Compound Thymoquinone for Colon Cancer Treatment

Given the need for novel and effective therapies for colon cancer, this study aimed to investigate the effects of 5-fluorouracil-loaded calcium carbonate nanoparticles (5FU-CaCO3np) combined with thymoquinone (TQ) against colon cancer. A shaking incubator and a high-speed homogenizer were used to prepare the optimal 5FU-CaCO3np, with characterizations of physicochemical properties, in vitro drug release profile, and biocompatibility. In vitro experiments and molecular docking were employed to evaluate the therapeutic potential of the combination for colon cancer treatment. Study results revealed that 5FU-CaCO3np with a size of approximately 130 nm was synthesized using the high-speed homogenizer. Its favorable biocompatibility, pH sensitivity, and sustained release properties facilitated reduced toxic side effects of 5-FU on NIH3T3 normal cells and enhanced inhibitory effects on CT26 colon cancer cells. The combination of 5FU-CaCO3np (1.875 μM) and TQ (30 μM) showed significantly superior anti-colon cancer effects to 5FU-CaCO3np alone in terms of cell proliferation and migration inhibition, cell apoptosis induction, and spheroid growth suppression in CT26 cells (p < 0.05), with strong interactions between the drugs and targets (E-cadherin, Bcl-2, PCNA, and MMP-2). These results provide evidence for 5FU-CaCO3np as a novel regimen against colon cancer. Combining 5FU-CaCO3np and TQ may offer a new perspective for colon cancer therapy.

Review of Prodrug and Nanodelivery Strategies to Improve the Treatment of Colorectal Cancer with Fluoropyrimidine Drugs

Fluoropyrimidine (FP) drugs are central components of combination chemotherapy regimens for the treatment of colorectal cancer (CRC). FP-based chemotherapy has improved survival outcomes over the last several decades with much of the therapeutic benefit derived from the optimization of dose and delivery. To provide further advances in therapeutic efficacy, next-generation prodrugs and nanodelivery systems for FPs are being developed. This review focuses on recent innovative nanodelivery approaches for FP drugs that display therapeutic promise. We summarize established, clinically useful FP prodrug strategies, including capecitabine, which exploit tumor-specific enzyme expression for optimal anticancer activity. We then describe the use of FP DNA-based polymers (e.g., CF10) for the delivery of activated FP nucleotides as a nanodelivery approach with proven activity in pre-clinical models and with clinical potential. Multiple nanodelivery systems for FP delivery show promise in CRC pre-clinical models and we review advances in albumin-mediated FP delivery, the development of mesoporous silica nanoparticles, emulsion-based nanoparticles, metal nanoparticles, hydrogel-based delivery, and liposomes and lipid nanoparticles that display particular promise for therapeutic development. Nanodelivery of FPs is anticipated to impact CRC treatment in the coming years and to improve survival for cancer patients.

Recent progress of targeted nanocarriers in diagnostic, therapeutic, and theranostic applications in colorectal cancer

Cancer at the lower end of the digestive tract, colorectal cancer (CRC), starts with asymptomatic polyps, which can be diagnosed as cancer at a later stage. It is the fourth leading cause of malignancy-associated mortality worldwide. Despite progress in conventional treatment strategies, the possibility to overcome the mortality and morbidity issues with the enhancement of the lifespan of CRC patients is limited. With the advent of nanocarrier-based drug delivery systems, a promising revolution has been made in diagnosis, treatment, and theranostic purposes for cancer management. Herein, we reviewed the progress of miniaturized nanocarriers, such as liposomes, niosomes, solid lipid nanoparticles, micelles, and polymeric nanoparticles, employed in passive and active targeting and their role in theranostic applications in CRC. With this novel scope, the diagnosis and treatment of CRC have proceeded to the forefront of innovation, where specific characteristics of the nanocarriers, such as processability, flexibility in developing precise architecture, improved circulation, site-specific delivery, and rapid response, facilitate the management of cancer patients. Furthermore, surface-engineered technologies for the nanocarriers could involve receptor-mediated deliveries towards the overexpressed receptors on the CRC microenvironment. Moreover, the potential of clinical translation of these targeted miniaturized formulations as well as the possible limitations and barriers that could impact this translation into clinical practice were highlighted. The advancement of these newest developments in clinical research and progress into the commercialization stage gives hope for a better tomorrow.

Antibody-Loaded Nanoplatforms for Colorectal Cancer Diagnosis and Treatment: An Update

At present, colorectal cancer (CRC) is the second deadliest type of cancer, partly because a high percentage of cases are diagnosed at advanced stages when tumors have already metastasized. Thus, there is an urgent need to develop novel diagnostic systems that allow early detection as well as new therapeutic systems that are more specific than those currently available. In this context, nanotechnology plays a very important role in the development of targeted platforms. In recent decades, many types of nanomaterials with advantageous properties have been used for nano-oncology applications and have been loaded with different types of targeted agents, capable of recognizing tumor cells or biomarkers. Indeed, among the different types of targeted agents, the most widely used are monoclonal antibodies, as the administration of many of them is already approved by the main drug regulatory agencies for the treatment of several types of cancer, including CRC. In this way, this review comprehensively discusses the main drawbacks of the conventional screening technologies and treatment for CRC, and it presents recent advances in the application of antibody-loaded nanoplatforms for CRC detection, therapy or theranostics applications.

Construction of nano slow-release systems for antibacterial active substances and its applications: A comprehensive review

At present, nano-carrier materials with antibacterial activity are of great significance. Due to the widespread resistance of many pathogenic microorganisms, it has seriously threatened human health. The natural antimicrobial substances extracted from fruits and vegetables can significantly improve their stability combined with nano-carrier materials. The resistance of pathogenic microorganisms will be substantially reduced, greatly enhancing the effect of active antimicrobial substances. Nanotechnology has excellent research prospects in the food industry, antibacterial preservation, food additives, food packaging, and other fields. This paper introduces nano-carrier materials and preparation techniques for loading and encapsulating active antibacterial substances in detail by constructing a nano-release system for active antibacterial substances. The antibacterial effect can be achieved by protecting them from adverse external conditions and destroying the membrane of pathogenic microorganisms. The mechanism of the slow release of the bacteriostatic active substance is also described. The mechanism of carrier loading and release is mainly through non-covalent forces between the bacteriostatic active substance and the carrier material, such as hydrogen bonding, π-π stacking, van der Waals forces, electrostatic interactions, etc., as well as the loading and adsorption of the bacteriostatic active substance by the chemical assembly. Finally, its wide application in food and medicine is introduced. It is hoped to provide a theoretical basis and technical support for the efficient utilization and product development of bacteriostatic active substances.

Aptamer Tethered Bio-Responsive Mesoporous Silica Nanoparticles for Efficient Targeted Delivery of Paclitaxel to Treat Ovarian Cancer Cells

Ovarian cancer is the leading cause of cancer deaths in female patients. The current therapeutics in ovarian cancer are limited and inefficient in curing the disease. To tackle this, we have synthesized tetrasulfide derivative of silica doped, biodegradable, glutathione-responsive targeted mesoporous silica nanoparticles modified with heterobifunctional polyethylene glycol as a linker and mucin-1 aptamer for triggered paclitaxel delivery to the ovarian cancer cells. Degradable mesoporous silica nanoparticles were synthesized by a modified sol-gel method with tetraethyl orthosilicate and Bis (triethoxysilylpropyl) tetrasulfide. The degradable mesoporous silica nanoparticles were characterized by dynamic light scattering, Fourier-transform infrared spectroscopy, Scanning electron microscopy and Transmission electron microscopy. The degradable mesoporous silica nanoparticles had good paclitaxel encapsulation efficiency and glutathione-responsive paclitaxel release ability. The glutathione utilization assay and visual destruction observed within 10 days in transmission electron microscopy images confirmed the degradation of the mesoporous silica nanoparticles in the tumor cell environment. The targeted degradable mesoporous silica nanoparticles were efficiently taken up by ovarian cancer cell lines OVACAR-3 and PA-1. The cytotoxicity of bare mesoporous silica nanoparticles evaluated on NIH-3T3 cell line showed good biocompatibility (>90% cell viability). Significant toxicity on OVACAR-3 (IC₅₀ 25.66 nM) and PA-1 (IC₅₀ 42.93 nM) cell lines was observed when treated with paclitaxel-loaded targeted degradable mesoporous silica nanoparticles. Results of this study demonstrated that mucin-1 targeted, glutathione-responsive mesoporous silica nanoparticles loaded with paclitaxel had a significant antitumor effect on ovarian cancer cells. All these findings demonstrated that developed nano-formulation could be suitable for ovarian cancer treatment.

Fabrication of Porous Fe-Based Metal-Organic Complex for the Enhanced Delivery of 5-Fluorouracil in In Vitro Treatment of Cancer Cells

Metal-organic complexes are one of the most studied materials in the last few decades, which are fabricated from organic ligands and metal ions to form robust frameworks with porous structures. In this work, iron-1,4-benzenedicarboxylic-polyethylene glycol (Fe-BDC-PEG) with a porous structure was successfully constructed by an iron(III) benzene dicarboxylate and polyethylene glycol diacid. The drug-delivery properties of the resultant Fe-BDC-PEG were tested for the loading and release of the 5-fluorouracil compound. The maximal loading capacity of Fe-BDC-PEG for 5-fluorouracil was determined to be 348.22 mg/g. The drug release of 5-fluorouracil-loaded Fe-BDC-PEG after 7 days was 92.69% and reached a maximum of 97.52% after 10 days. The 7 day and acute oral toxicity of Fe-BDC-PEG in mice were studied. The results show that no reasonable change or mortality was observed upon administration of Fe-BDC-PEG complex in mice at 10 g/kg body weight. When the uptake of Fe-BDC-PEG particles in mice was continued for 7 consecutive days, the mortality, feed consumption, body weight, and daily activity were negligibly changed.

5-Fluorouracil crystal-incorporated, pH-responsive, and release-modulating PLGA/Eudragit FS hybrid microparticles for local colorectal cancer-targeted chemotherapy

5-Fluorouracil (5-FU) is a widely used chemotherapeutic agent for colorectal cancer (CRC) owing to its potent anticancer effects. However, severe systemic side effects and poor drug accumulation in the CRC tissues limit its efficacy. This study aimed to develop 5-FU crystal-incorporated, pH-responsive, and release-modulating poly(d,l-lactide-co-glycolide)/Eudragit FS hybrid microparticles (5FU-EPMPs) for the local CRC-targeted chemotherapy. Approximately 150 μm 5FU-EPMPs were fabricated via the S/O/W emulsion solvent evaporation method, with 7.93 ± 0.24% and 87.23 ± 2.64% 5-FU loading and encapsulation efficiencies, respectively. Drug release profiles in a simulated pH environment of the gastrointestinal tract revealed that premature 5-FU release in the stomach and small intestine was prevented, thereby minimizing systemic 5-FU absorption. After reaching the colon, 5-FU was continuously released for >15 h, allowing long-term exposure of CRC tissues to sufficient 5-FU concentrations. Furthermore, in a CRC mouse model, the 5FU-EPMPs showed potent inhibition of tumor growth without signs of systemic toxicity. Thus, the 5FU-EPMPs represent a promising drug delivery system for local CRC-targeted chemotherapy.

A review on the latest developments of mesoporous silica nanoparticles as a promising platform for diagnosis and treatment of cancer

Cancer is the second cause of human mortality after cardiovascular disease around the globe. Conventional cancer therapies are chemotherapy, radiation, and surgery. In fact, due to the lack of absolute specificity and high drug concentrations, early recognition and treatment of cancer with conventional approaches have become challenging issues in the world. To mitigate against the limitations of conventional cancer chemotherapy, nanomaterials have been developed. Nanomaterials exhibit particular properties that can overcome the drawbacks of conventional therapies such as lack of specificity, high drug concentrations, and adverse drug reactions. Among nanocarriers, mesoporous silica nanoparticles (MSNs) have gained increasing attention due to their well-defined pore size and structure, high surface area, good biocompatibility and biodegradability, ease of surface modification, and stable aqueous dispersions. This review highlights the current progress with the use of MSNs for the delivery of chemotherapeutic agents for the diagnosis and treatment of cancer. Various stimuli-responsive gatekeepers, which endow the MSNs with on-demand drug delivery, surface modification strategies for targeting purposes, and multifunctional MSNs utilized in drug delivery systems (DDSs) are also addressed. Also, the capability of MSNs as flexible imaging platforms is considered. In addition, physicochemical attributes of MSNs and their effects on cancer therapy with a particular focus on recent studies is emphasized. Moreover, major challenges to the use of MSNs for cancer therapy, biosafety and cytotoxicity aspects of MSNs are discussed.

An updated review on properties, nanodelivery systems, and analytical methods for the determination of 5-fluorouracil in pharmaceutical and biological samples

Abstract:

5-Fluorouracil (5-FU) is an antimetabolite drug used for over 70 years as first-line chemotherapy to treat various types of cancer, such as head, neck, breast and colorectal cancer. 5-FU acts mainly by inhibiting thymidylate synthase, thereby interfering with deoxyribonucleic acid (DNA) replication or by 5-FU incorporating into DNA, causing damage to the sequence of nucleotides. Being analogous to uracil, 5-FU enters cells using the same transport mechanism, where a is converted into active metabolites such as fluorouridine triphosphate (FUTP), fluorodeoxyuridine monophosphate (FdUMP), and fluorodeoxyuridine triphosphate (FdUTP). Currently, there are several nanodelivery systems being developed and evaluated at the preclinical level to overcome existing limitations to 5-FU chemotherapy, including liposomes, polymeric nanoparticles, polymeric micelles, nanoemulsions, mesoporous silica nanoparticles, and solid lipid nanoparticles. Therefore, it is essential to choose and develop suitable analytical methods for the quantification of 5-FU and its metabolites (5-fluorouridine and 5-fluoro-2-deoxyuridine) in pharmaceutical and biological samples. Among the analytical techniques, chromatographic methods are commonly the most used for the quantification of 5-FU from different matrices. However, other analytical methods have also been developed for the determination of 5-FU, such as electrochemical methods, a sensitive, selective, and precise technique, in addition to having a reduced cost. Here, we first review the physicochemical properties, mechanism of action, and advances in 5-FU nanodelivery systems. Next, we summarize the current progress of other chromatographic methods described to determine 5-FU. Lastly, we discuss the advantages of electrochemical methods for the identification and quantification of 5-FU and its metabolites in pharmaceutical and biological samples.

Recent progress in the applications of silica-based nanoparticles

Functionalized silica nanoparticles (SiO2 NPs) have attracted great attention due to their promising distinctive, versatile, and privileged physiochemical characteristics. These enhanced properties make this type of functionalized nanoparticles particularly appropriate for different applications. A lack of reviews that summarizes the fabrications of such nanomaterials and their different applications in the same work has been observed in the literature. Therefore, in this work, we will discuss the recent signs of progress in the fabrication of functionalized silica nanoparticles and their attractive applications that have been extensively highlighted (advanced catalysis, drug-delivery, biomedical applications, environmental remediation applications, and wastewater treatment). These applications have been selected for demonstrating the role of the surface modification step on the various properties of the silica surface. In addition, the current challenges in the applications of functionalized silica nanoparticles and corresponding strategies to discuss these issues and future perspectives for additional improvement have been addressed.

A Nanoparticle's Journey to the Tumor: Strategies to Overcome First-Pass Metabolism and Their Limitations

Simple Summary

Traditional cancer therapeutics suffer from off-target toxicity, limiting their effective dose and preventing patients’ tumors from being sufficiently treated by chemotherapeutics alone. Nanomedicine is an emerging class of therapeutics in which a drug is packaged into a nanoparticle that promotes uptake of the drug at a tumor site, shielding it from uptake by peripheral organs and enabling the safe delivery of chemotherapeutics that have poor aqueous solubility, short plasma half-life, narrow therapeutic window, and toxic side effects. Despite the advantages of nanomedicines for cancer, there remains significant challenges to improve uptake at the tumor and prevent premature clearance from the body. In this review, we summarize the effects of first-pass metabolism on a nanoparticle’s journey to a tumor and outline future steps that we believe will improve the efficacy of cancer nanomedicines.

Abstract

Nanomedicines represent the cutting edge of today’s cancer therapeutics. Seminal research decades ago has begun to pay dividends in the clinic, allowing for the delivery of cancer drugs with enhanced systemic circulation while also minimizing off-target toxicity. Despite the advantages of delivering cancer drugs using nanoparticles, micelles, or other nanostructures, only a small fraction of the injected dose reaches the tumor, creating a narrow therapeutic window for an otherwise potent drug. First-pass metabolism of nanoparticles by the reticuloendothelial system (RES) has been identified as a major culprit for the depletion of nanoparticles in circulation before they reach the tumor site. To overcome this, new strategies, materials, and functionalization with stealth polymers have been developed to improve nanoparticle circulation and uptake at the tumor site. This review summarizes the strategies undertaken to evade RES uptake of nanomedicines and improve the passive and active targeting of nanoparticle drugs to solid tumors. We also outline the limitations of current strategies and the future directions we believe will be explored to yield significant benefits to patients and make nanomedicine a promising treatment modality for cancer.

Ultrasonic-Assisted Synthesis of Fe-BTC-PEG Metal-Organic Complex: An Effective and Safety Nanocarrier for Anticancer Drug Delivery

The porous metal-organic complexes are emerging as novel carriers for effective and safe delivery of drugs for cancer treatment, minimizing the side effect of drug overuse during cancer treatment. This study fabricated the Fe-BTC-PEG metal-organic complex from Fe ions, trimesic acid, and poly(ethylene glycol) as precursors using an ultrasonic-assisted method. The morphology and crystallinity of the resultant complex were observed by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. FTIR spectroscopy was employed to investigate the functional groups on the surface of the Fe-BTC-PEG complex. The result showed that the prepared Fe-BTC-PEG complex was in particle form with low crystallinity and diameter ranging from 100 to 200 nm. The obtained Fe-BTC-PEG complex exhibited a high loading capacity for the 5-fluorouracil (5-FU) anticancer drug with a maximal capacity of 364 mg/g. The releasing behavior of 5-fluorouracil from the 5-FU-loaded Fe-BTC-PEG complex was studied. Notably, the acute oral toxicity of the Fe-BTC-PEG metal-organic complex was also carried out to evaluate the safety of the material in practical application.

A Review on Drug Delivery System for Tumor Therapy

In recent years, with the development of nanomaterials, the research of drug delivery systems has become a new field of cancer therapy. Compared with conventional antitumor drugs, drug delivery systems such as drug nanoparticles (NPs) are expected to have more advantages in antineoplastic effects, including easy preparation, high efficiency, low toxicity, especially active tumor-targeting ability. Drug delivery systems are usually composed of delivery carriers, antitumor drugs, and even target molecules. At present, there are few comprehensive reports on a summary of drug delivery systems applied for tumor therapy. This review introduces the preparation, characteristics, and applications of several common delivery carriers and expounds the antitumor mechanism of different antitumor drugs in delivery carriers in detail which provides a more theoretical basis for clinical application of personalized cancer nanomedicine in the future.

Nanocarriers as a Tool for the Treatment of Colorectal Cancer

Nanotechnology is a promising tool for the treatment of cancer. In the past decades, major steps have been made to bring nanotechnology into the clinic in the form of nanoparticle-based drug delivery systems. The great hope of drug delivery systems is to reduce the side effects of chemotherapeutics while simultaneously increasing the efficiency of the therapy. An increased treatment efficiency would greatly benefit the quality of life as well as the life expectancy of cancer patients. However, besides its many advantages, nanomedicines have to face several challenges and hurdles before they can be used for the effective treatment of tumors. Here, we give an overview of the hallmarks of cancer, especially colorectal cancer, and discuss biological barriers as well as how drug delivery systems can be utilized for the effective treatment of tumors and metastases.

Recent Advances in Mesoporous Silica Nanoparticles for Targeted Drug Delivery applications

Nanotechnology provides the means to design and fabricate delivery vehicles capable of overcoming physiologically imposed obstacles and undesirable side effects of systemic drug delivery. This protocol allows maximal targeting effectiveness and therefore enhances therapeutic efficiency. In recent years, mesoporous silica nanoparticles (MSNPs) have sparked interest in the nanomedicine research community, particularly for their promising applications in cancer treatment. The intrinsic physio-chemical stability, facile functionalization, high surface area, low toxicity, and great loading capacity for a wide range of chemotherapeutic agents make MSNPs very appealing candidates for controllable drug delivery systems. Importantly, the peculiar nanostructures of MSNPs enabled them to serve as an effective drug, gene, protein, and antigen delivery vehicle for a variety of therapeutic regimens. For these reasons, in this review article, we underscore the recent progress in the design and synthesis of MSNPs and the parameters influencing their characteristic features and activities. In addition, the process of absorption, dissemination, and secretion by injection or oral management of MSNPs are also discussed, as they are key directions for the potential utilization of MSNPs. Factors influencing the in vivo fate of MSNPs will also be highlighted, with the main focus on particle size, morphology, porosity, surface functionality, and oxidation. Given that combining other functional materials with MSNPs may increase their biological compatibility, monitor drug discharge, or improve absorption by tumor cells coated MSNPs; these aspects are also covered and discussed herein.

Forward Precision Medicine: Micelles for Active Targeting Driven by Peptides

Precision medicine is based on innovative administration methods of active principles. Drug delivery on tissue of interest allows improving the therapeutic index and reducing the side effects. Active targeting by means of drug-encapsulated micelles decorated with targeting bioactive moieties represents a new frontier. Between the bioactive moieties, peptides, for their versatility, easy synthesis and immunogenicity, can be selected to direct a drug toward a considerable number of molecular targets overexpressed on both cancer vasculature and cancer cells. Moreover, short peptide sequences can facilitate cellular intake. This review focuses on micelles achieved by self-assembling or mixing peptide-grafted surfactants or peptide-decorated amphiphilic copolymers. Nanovectors loaded with hydrophobic or hydrophilic cytotoxic drugs or with gene silence sequences and externally functionalized with natural or synthetic peptides are described based on their formulation and in vitro and in vivo behaviors.

Nanocarriers for Biomedicine: From Lipid Formulations to Inorganic and Hybrid Nanoparticles

Encapsulation of cargoes in nanocontainers is widely used in different fields to solve the problems of their solubility, homogeneity, stability, protection from unwanted chemical and biological destructive effects, and functional activity improvement. This approach is of special importance in biomedicine, since this makes it possible to reduce the limitations of drug delivery related to the toxicity and side effects of therapeutics, their low bioavailability and biocompatibility. This review highlights current progress in the use of lipid systems to deliver active substances to the human body. Various lipid compositions modified with amphiphilic open-chain and macrocyclic compounds, peptide molecules and alternative target ligands are discussed. Liposome modification also evolves by creating new hybrid structures consisting of organic and inorganic parts. Such nanohybrid platforms include cerasomes, which are considered as alternative nanocarriers allowing to reduce inherent limitations of lipid nanoparticles. Compositions based on mesoporous silica are beginning to acquire no less relevance due to their unique features, such as advanced porous properties, well-proven drug delivery efficiency and their versatility for creating highly efficient nanomaterials. The types of silica nanoparticles, their efficacy in biomedical applications and hybrid inorganic-polymer platforms are the subject of discussion in this review, with current challenges emphasized.

Exploring pH dependent delivery of 5-fluorouracil from functionalized multi-walled carbon nanotubes

Multi-walled carbon nanotubes (MWCNTs) can be applied for pH-sensitive delivery of anticancer drugs. Due to the importance of 5-fluorouracil (5-FU) in different tumor therapy regimens, it has been widely used in different pH dependent drug delivery systems. To investigate the pH effects on loading (and release) of 5-FU on (and from) the functionalized MWCNTs and propose the optimum condition for drug delivery, both macroscopic and microscopic studies were carried out using chromatography and molecular dynamic simulation at different conditions. For both levels of studies, different analytical approaches were performed to assess the validity of the methods. The experimental results revealed that 5-FU has more binding affinity to the surface of the nanocarrier at physiological pH (pH = 7.4) and showed more release at acidic conditions (pH = 5.0). Meanwhile it has been observed that basic pH (pH = 9.0) can lead to a dramatic decrease effect on loading of the drug. The results of this study can be used to suggest the optimum pH levels for nanocarbon based formulations of 5-FU in cancer therapy.

Ultrasound-mediated gene delivery into suspended plant cells using polyethyleneimine-coated mesoporous silica nanoparticles

Sonoporation, ultrasound-mediated membrane perforation can potentially puncture plasma membrane and rigid cell wall on presumably reversible basis which benefit gene transfection and plant biotechnology. Herein, positively charged poly-ethyleneimine (PEI)-coated mesoporous silica nanoparticles (MSNs) with an average diameter of 100 ± 8.7 nm was synthesized for GUS-encoding plasmid delivery into the suspended tobacco cells using the ultrasound treatment. The overall potential of PEI-MSN for DNA adsorption was measured at 43.43 μg DNA mg-1 PEI-MSNs. It was shown that high level of sonoporation may adversely upset the cell viability. Optimal conditions of ultrasonic treatment are obtained as 8 min at 3 various intensities of 160, 320 and 640 W. Histochemical staining assay was used to follow the protein expression. It was shown that PEI-coated MSNs efficiently transfer the GUS-encoding plasmid DNA into the tobacco cells. The results of this study showed that ultrasonic treatment provides an economical and straightforward approach for gene transferring into the plant cells without any need to complicated devices and concerns about safety issues.

Targeted drug delivery strategies for precision medicines

Progress in the field of precision medicine has changed the landscape of cancer therapy. Precision medicine is propelled by technologies that enable molecular profiling, genomic analysis, and optimized drug design to tailor treatments for individual patients. Although precision medicines have resulted in some clinical successes, the use of many potential therapeutics has been hindered by pharmacological issues, including toxicities and drug resistance. Drug delivery materials and approaches have now advanced to a point where they can enable the modulation of a drug's pharmacological parameters without compromising the desired effect on molecular targets. Specifically, they can modulate a drug's pharmacokinetics, stability, absorption, and exposure to tumours and healthy tissues, and facilitate the administration of synergistic drug combinations. This Review highlights recent progress in precision therapeutics and drug delivery, and identifies opportunities for strategies to improve the therapeutic index of cancer drugs, and consequently, clinical outcomes.

Triumph against cancer: invading colorectal cancer with nanotechnology

INTRODUCTION

Recent statistics have reported colorectal cancer (CRC) as the second leading cause of cancer-associated deaths in the world. Early diagnosis of CRC may help to reduce the mortality and associated complications. However, the conventional diagnostic techniques often lead to misdiagnosis, fail to differentiate benign from malignant tissue or diagnose only at an advanced stage. For the treatment of CRC, surgery, chemotherapy, immunotherapy, and radiotherapy have been employed. However, the quality of living of the CRC patients is highly compromised after employing current therapeutic approaches owing to the toxicity issues and relapse.

AREA COVERED

This review accentuates the molecular mechanisms involved in the pathogenesis, stages of CRC, conventional approaches for diagnosis and therapy of CRC and the issues confronted thereby. It provides an outlook on the advantages of employing nanotechnology-based approaches for prevention, early diagnosis, and treatment of CRC.

EXPERT OPINION

Employing nanotechnology-based approaches has demonstrated promising outcomes in the prevention, diagnosis, and treatment of CRC. Nanotechnology-based approaches can surmount the major drawbacks of traditional diagnostic and therapeutic approaches. Nanotechnology bestows the advantage of early detection of CRC which helps to undertake instant steps for offering efficient therapy and reducing the mortality rates. For the treatment of CRC, nanocarriers offer the benefit of achieving controlled drug release, improved drug bioavailability, enhanced tumor targetability and reduced adverse effects.

Cetuximab functionalization strategy for combining active targeting and antimigration capacities of a hybrid composite nanoplatform applied to deliver 5-fluorouracil: toward colorectal cancer treatment

Antibody-functionalized targeted nanocarriers to deliver chemotherapeutics have been widely explored. However, it remains highly desirable to understand and apply the antitumor potential of antibodies integrated in hybrid composite nanoplatforms. Herein, mesoporous silica nanoparticles, a supported lipid bilayer and cetuximab were integrated to fabricate a hybrid nanoplatform for effectively encapsulating and selectively delivering 5-fluorouracil (5-FU) against colorectal cancer (CRC) cells. The specially designed nanoplatform exhibited superior properties, such as satisfying size distribution, dispersity and stability, drug encapsulation, controlled release, and cellular uptake. Interestingly, the modification of cetuximab onto nanoplatforms without drug loading can significantly inhibit the migration and invasion of CRC cells through suppressing the epidermal growth factor receptor (EGFR)-associated signaling pathway. Furthermore, delivery of 5-FU by using this nanoplatform can remarkably induce cytotoxicity, cell cycle arrest, and cell apoptosis for CRC cells with high EGFR expression. Overall, this nanostructured platform can dramatically improve the tumor killing effects of encapsulated chemotherapeutics and present antimigration effects derived from the antibody modified on it. Moreover, in vivo biodistribution experiments demonstrated the superior tumor targeting ability of the targeted nanoparticles. Thus, this targeted nanoplatform has substantial potential in combinational therapy of antibodies and chemotherapy agents against colorectal cancer.

Engineered nanoparticles for imaging and drug delivery in colorectal cancer

Colorectal cancer (CRC) is one of the deadliest diseases worldwide due to a lack of early detection methods and appropriate drug delivery strategies. Conventional imaging techniques cannot accurately distinguish benign from malignant tissue, leading to frequent misdiagnosis or diagnosis at late stages of the disease. Novel screening tools with improved accuracy and diagnostic precision are thus required to reduce the mortality burden of this malignancy. Additionally, current therapeutic strategies, including radio- and chemotherapies carry adverse side effects and are limited by the development of drug resistance. Recent advances in nanotechnology have rendered it an attractive approach for designing novel clinical solutions for CRC. Nanoparticle-based formulations could assist early tumor detection and help to overcome the limitations of conventional therapies including poor aqueous solubility, nonspecific biodistribution and limited bioavailability. In this review, we shed light on various types of nanoparticles used for diagnosis and drug delivery in CRC. In addition, we will explore how these nanoparticles can improve diagnostic accuracy and promote selective drug targeting to tumor sites with increased efficiency and reduced cytotoxicity against healthy colon tissue.

Polymer-hybrid nanoparticles: Current advances in biomedical applications

The unique properties of polymer-hybrid nanosystems enable them to play an important role in different fields such as biomedical applications. Hybrid materials, which are formed by polymer and inorganic- or organic-base systems, have been the focus of many recently published studies whose results have shown outstanding improvements in drug targeting. The development of hybrid polymer materials can avoid the synthesis of new molecules, which is an overall expensive process that can take several years to get to the proper elaboration and approval. Thus, the combination of properties in a single hybrid system can have several advantages over non-hybrid platforms, such as improvements in circulation time, structural disintegration, high stability, premature release, low encapsulation rate and unspecific release kinetics. Thus, the aim of the present review is to outline a rapid and well-oriented scenario concerning the knowledge about polymer-hybrid nanoparticles use in biomedical platforms. Furthermore, the ultimate methodologies adopted in synthesis processes, as well as in applications in vitro/in vivo, are the focus of this review.

Multimodal Decorations of Mesoporous Silica Nanoparticles for Improved Cancer Therapy

The presence of leaky vasculature and the lack of lymphatic drainage of small structures by the solid tumors formulate nanoparticles as promising delivery vehicles in cancer therapy. In particular, among various nanoparticles, the mesoporous silica nanoparticles (MSN) exhibit numerous outstanding features, including mechanical thermal and chemical stability, huge surface area and ordered porous interior to store different anti-cancer therapeutics with high loading capacity and tunable release mechanisms. Furthermore, one can easily decorate the surface of MSN by attaching ligands for active targeting specifically to the cancer region exploiting overexpressed receptors. The controlled release of drugs to the disease site without any leakage to healthy tissues can be achieved by employing environment responsive gatekeepers for the end-capping of MSN. To achieve precise cancer chemotherapy, the most desired delivery system should possess high loading efficiency, site-specificity and capacity of controlled release. In this review we will focus on multimodal decorations of MSN, which is the most demanding ongoing approach related to MSN application in cancer therapy. Herein, we will report about the recently tried efforts for multimodal modifications of MSN, exploiting both the active targeting and stimuli responsive behavior simultaneously, along with individual targeted delivery and stimuli responsive cancer therapy using MSN.

Functionalized mesoporous silica nanoparticles in anticancer therapeutics

The application of nanomedicines in tumor targeting and attaining meaningful therapeutic benefits for the treatment of cancers has been going on for almost two decades. Beyond the lipidic and polymeric nanomedicines-based passive and active targeting, the quest for inventing the new generation of carriers has no end. This has lead to the evolution of some of the unique carrier systems with supramolecular assembly structures. Mesoporous nanoparticulate systems (MSNPs) are the recently explored substances with favorable potential for drug delivery and drug targeting applications especially in cancer chemotherapeutics. Notwithstanding their physical properties that makes them a suitable carrier for cancer treatment, but their outstanding ability towards chemical functionalization helps in delivering the imaging agents for diagnostic applications. MSNPs can improve the dissolution rate and systemic availability of the poorly water soluble drugs due to their mesoporous structures. Besides, guest molecules including targeting ligands, biomimetic agents, fluorescent dyes, and biocompatible polymers can be efficiently encapsulated in their tunable porous structure for targeting purpose. Some special features of the MSNPs which make them one of the highly effective nanocarrier systems include their ability to encapsulate non-crystalline drugs in their mesopores, high dispersion ability as a function of large surface area and wetting properties. For anticancer drug delivery, MSNPs are worthful to provide excellent drug loading capacity and endocytotic behavior. Moreover, the external surface of MSNPs can be precisely modified for tumor-recognition and developing sensitivity of the antitumor agents towards the cancer cells. Owing to the innumerable applications of MSNPs till now in cancer treatment, the present article particularly focuses to provide an overview account with complete details on the topic to make the readers abreast with details on physiochemical and material properties of MSNPs, their applications and current innovations for the purpose.

Recent advancements in mesoporous silica nanoparticles towards therapeutic applications for cancer

Recently, drug delivery systems based on nanotechnology have received great attention in cancer therapeutics and diagnostics since they can not only improve the treatment efficacy but also reduce the side effects. Among them, mesoporous silica nanoparticles (MSNs) with large surface area, high pore volume, tunable pore size, abundant surface chemistry, and acceptable biocompatibility exhibit unique advantages and are considered as promising candidates for cancer diagnosis and therapy. In this review, we update the recent progress on MSN-based systems for cancer treatment purposes. We also discuss the drug loading mechanism of MSNs, stimuli-responsive drug release, and surface modification strategies for improving biocompatibility, and targeting functionalities. STATEMENT OF SIGNIFICANCE: The development of MSN-based delivery systems that can be used in both diagnosis and treatment of cancer has attracted tremendous interest in the past decade. MSN-based delivery systems can improve therapeutic efficacy and reduce cytotoxicity to normal tissue. To further improve the in vivo properties of MSNs and potential translation to the clinics, it is critical to design MSNs with appropriate surface engineering and desirable cancer targeting. This review is intended to provide the readers a comprehensive background of the vast literature till date on silica-based drug delivery systems, and to inspire further innovations in silica nanomedicine in the future.

Mesoporous silica nanoparticles for therapeutic/diagnostic applications

Based on unique intrinsic properties of mesoporous silica nanoparticles (MSNs) such as high surface area, large pore size, good biocompatibility and biodegradability, stable aqueous dispersion, they have received much attention in the recent decades for their applications as a promising platform in the biomedicine field. These porous structures possess a pore size ranging from 2 to 50 nm which make them excellent candidates for various biomedical applications. Herein, at first we described the common approaches of cargo loading and release processes from MSNs. Then, the intracellular uptake, safety and cytotoxicity aspects of MSNs are discussed as well. This review also highlights the most recent advances in the biomedical applications of MSNs, including 1) MSNs-based carriers, 2) MSNs as bioimaging agents, 3) MSNs-based biosensors, 4) MSNs as therapeutic agents (photodynamic therapy), 5) MSN based quantum dots, 6) MSNs as platforms for upconverting nanoparticles, and 6) MSNs in tissue engineering.

Silica-based organic-inorganic hybrid nanoparticles and nanoconjugates for improved anticancer drug delivery

After the introduction of first generation MSNs for drug delivery with some challenges such as large particle sizes, irregular morphologies and aggregations, second generation provided uniform spherical morphologies, tunable pore/particle sizes and compositions. Henceforth, organic-inorganic hybrid mesoporous silica nanosystems have grown rapidly and utilized for active and passive targeting of tumorigenic cells especially conjugated with organic polymers followed by third generation counterparts with improved functionalities for cancer therapy. The aim of this review article is to focus on the advancements in mesoporous silica based organic-inorganic hybrid nanoparticles developed as drug carriers targeting cancer cells. Brief introduction to the state-of-the-art in passive and active targeting methods is presented. Specifically, therapeutic, diagnostic and theranostic applications are discussed with emphases on triggered and ligand conjugated organic-inorganic hybrid mesoporous silica nanomaterials. Although mesoporous silica nanoparticles perform well in preclinical tests, clinical translation progresses slowly as appropriate doses needs to be evaluated for human use along with biocompatibility and efficiency depending on surface modifications.

A Single-Step Surface Modification of Electrospun Silica Nanofibers Using a Silica Binding Protein Fused with an RGD Motif for Enhanced PC12 Cell Growth and Differentiation

In this study, a previously known high-affinity silica binding protein (SB) was genetically engineered to fuse with an integrin-binding peptide (RGD) to create a recombinant protein (SB-RGD). SB-RGD was successfully expressed in Escherichia coli and purified using silica beads through a simple and fast centrifugation method. A further functionality assay showed that SB-RGD bound to the silica surface with an extremely high affinity that required 2 M MgCl₂ for elution. Through a single-step incubation, the purified SB-RGD proteins were noncovalently coated onto an electrospun silica nanofiber (SNF) substrate to fabricate the SNF-SB-RGD substrate. SNF-SB-RGD was characterized by a combination of scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and immunostaining fluorescence microscopy. As PC12 cells were seeded onto the SNF-SB-RGD surface, significantly higher cell viability and longer neurite extensions were observed when compared to those on the control surfaces. These results indicated that SB-RGD could serve as a noncovalent coating biologic to support and promote neuron growth and differentiation on silica-based substrates for neuronal tissue engineering. It also provides proof of concept for the possibility to genetically engineer protein-based signaling molecules to noncovalently modify silica-based substrates as bioinspired material.