Trans-resveratrol loaded chitosan nanoparticles modified with biotin and avidin to target hepatic carcinoma

Research Progress of Chitosan-based Multifunctional Nanoparticles in Cancer Targeted Therapy

Conventional tumor therapeutic modalities, such as radiotherapy, chemotherapy, and surgery, involve low tumor inhibition efficiency, non-targeted drug delivery, and side effects. The development of novel and practical nano-drug delivery systems (DDSs) for targeted tumor therapy has become particularly important. Among various bioactive nanoparticles, chitosan is considered a suitable candidate for drug delivery due to its nontoxicity, good biocompatibility, and biodegradability. The amino and hydroxyl groups of chitosan endow it with the diverse function of chemical modification, thereby improving its physical and biological properties to meet the requirements of advanced biomedical applications. Therefore, it is necessary to review the property and applications of chitosan- based materials in biomedicine. In this review, the characteristics of chitosan related to its applications are first introduced, and then the preparation and modification of chitosan-based nanoparticles, including the function tailoring of chitosan-modified nanoparticles, are demonstrated and discussed. Finally, the opportunities and challenges of chitosan- based nanomaterials in this emerging field are proposed from the perspective of the rational and systematic design for the biomedicine field.

Nanoparticles loaded with pharmacologically active plant-derived natural products: Biomedical applications and toxicity

Pharmacologically active natural products have played a significant role in the history of drug development. They have acted as sources of therapeutic drugs for various diseases such as cancer and infectious diseases. However, most natural products suffer from poor water solubility and low bioavailability, limiting their clinical applications. The rapid development of nanotechnology has opened up new directions for applying natural products and numerous studies have explored the biomedical applications of nanomaterials loaded with natural products. This review covers the recent research on applying plant-derived natural products (PDNPs) nanomaterials, including nanomedicines loaded with flavonoids, non-flavonoid polyphenols, alkaloids, and quinones, especially their use in treating various diseases. Furthermore, some drugs derived from natural products can be toxic to the body, so the toxicity of them is discussed. This comprehensive review includes fundamental discoveries and exploratory advances in natural product-loaded nanomaterials that may be helpful for future clinical development.

Polymeric Nanoparticles for Delivery of Natural Bioactive Agents: Recent Advances and Challenges

In the last few decades, several natural bioactive agents have been widely utilized in the treatment and prevention of many diseases owing to their unique and versatile therapeutic effects, including antioxidant, anti-inflammatory, anticancer, and neuroprotective action. However, their poor aqueous solubility, poor bioavailability, low GIT stability, extensive metabolism as well as short duration of action are the most shortfalls hampering their biomedical/pharmaceutical applications. Different drug delivery platforms have developed in this regard, and a captivating tool of this has been the fabrication of nanocarriers. In particular, polymeric nanoparticles were reported to offer proficient delivery of various natural bioactive agents with good entrapment potential and stability, an efficiently controlled release, improved bioavailability, and fascinating therapeutic efficacy. In addition, surface decoration and polymer functionalization have opened the door to improving the characteristics of polymeric nanoparticles and alleviating the reported toxicity. Herein, a review of the state of knowledge on polymeric nanoparticles loaded with natural bioactive agents is presented. The review focuses on frequently used polymeric materials and their corresponding methods of fabrication, the needs of such systems for natural bioactive agents, polymeric nanoparticles loaded with natural bioactive agents in the literature, and the potential role of polymer functionalization, hybrid systems, and stimuli-responsive systems in overcoming most of the system drawbacks. This exploration may offer a thorough idea of viewing the polymeric nanoparticles as a potential candidate for the delivery of natural bioactive agents as well as the challenges and the combating tools used to overcome any hurdles.

The anti‐cancer effect of chitosan/resveratrol polymeric nanocomplex against triple‐negative breast cancer; an in vitro assessment

Herein, the authors synthesised chitosan nanoparticles (Cs NPs) as a resveratrol (RSV) carrier and evaluated their efficacy in stimulating apoptosis in MDA-MB 231 cells. Blank (Cs NPs) and RSV- Cs NPs (RSV-Cs NPs) were synthesised via ionic gelation and characterised by using fourier-transform infrared spectroscopy (FTIR), Scanning electron microscope, dynamic light scattering/Zeta potential and RSV release. MDA-MB 231 cells were treated with RSV, Cs NPs and RSV-Cs NPs (24, 48, and 72 h), followed by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. Cell toxicity was evaluated using lactate dehydrogenase assay, and real-time polymerase chain reaction was performed to explore apoptosis induction. FTIR spectra confirmed the NPs via the formation of cross-linking bonds. Cs and RSV-Cs NPs sizes were about 75 and 198 nm with 14 and 24 mV zeta potentials. The RSV entrapment efficiency was 52.34 ± 0.16%, with an early rapid release followed by a sustained manner. Cs and RSV-Cs NPs inhibited cell proliferation at lower concentrations and IC50 values. RSV-Cs NPs had the most cytotoxic effect and stimulated intrinsic apoptotic pathway, indicated by increased Bcl-2-associated x (BAX), BAX/Bcl-2 ratio, P53 expressions, reduced Bcl-2 and upregulated caspases 3, 8 and 9. RSV-Cs NPs have a great potential to suppress invasive breast cancer cell proliferation by targeting mitochondrial metabolism and inducing the intrinsic apoptotic pathway.

Applications of resveratrol in the treatment of gastrointestinal cancer

Natural product compounds have lately attracted interest in the scientific community as a possible treatment for gastrointestinal (GI) cancer, due to their anti-inflammatory and anticancer properties. There are many preclinical, clinical, and epidemiological studies, suggesting that the consumption of polyphenol compounds, which are abundant in vegetables, grains, fruits, and pulses, may help to prevent various illnesses and disorders from developing, including several GI cancers. The development of GI malignancies follows a well-known path, in which normal gastrointestinal cells acquire abnormalities in their genetic composition, causing the cells to continuously proliferate, and metastasize to other sites, especially the brain and liver. Natural compounds with the ability to affect oncogenic pathways might be possible treatments for GI malignancies, and could easily be tested in clinical trials. Resveratrol is a non-flavonoid polyphenol and a natural stilbene, acting as a phytoestrogen with anti-cancer, cardioprotective, anti-oxidant, and anti-inflammatory properties. Resveratrol has been shown to overcome resistance mechanisms in cancer cells, and when combined with conventional anticancer drugs, could sensitize cancer cells to chemotherapy. Several new resveratrol analogs and nanostructured delivery vehicles with improved anti-GI cancer efficacy, absorption, and pharmacokinetic profiles have already been developed. This present review focuses on the in vitro and in vivo effects of resveratrol on GI cancers, as well as the underlying molecular mechanisms of action.

Stilbenes: Characterization, bioactivity, encapsulation and structural modifications. A review of their current limitations and promising approaches

Stilbenes are phenolic compounds naturally synthesized as secondary metabolites by the shikimate pathway in plants. Research on them has increased in recent years due to their therapeutic potential as antioxidant, antimicrobial, anti-inflammatory, anticancer, cardioprotective and anti-obesity agents. Amongst them, resveratrol has attracted the most attention, although there are other natural and synthesized stilbenes with enhanced properties. However, stilbenes have some physicochemical and pharmacokinetic problems that need to be overcome before considering their applications. Human clinical evidence of their bioactivity is still controversial due to this fact and hence, exhaustive basis science on stilbenes is needed before applied science. This review gathers the main physicochemical and biological properties of natural stilbenes, establishes structure-activity relationships among them, emphasizing the current problems that limit their applications and presenting some promising approaches to overcome these issues: the encapsulation in different agents and the structural modification to obtain novel stilbenes with better features. The bioactivity of stilbenes should move from promising to evident.

Construction of IL-13 Receptor α2-Targeting Resveratrol Nanoparticles against Glioblastoma Cells: Therapeutic Efficacy and Molecular Effects

Glioblastoma multiforme (GBM) is the most common lethal primary brain malignancy without reliable therapeutic drugs. IL-13Rα2 is frequently expressed in GBMs as a molecular marker. Resveratrol (Res) effectively inhibits GBM cell growth but has not been applied in vivo because of its low brain bioavailability when administered systemically. A sustained-release and GBM-targeting resveratrol form may overcome this therapeutic dilemma. To achieve this goal, encapsulated Res 30 ± 4.8 nm IL-13Rα2-targeting nanoparticles (Pep-PP@Res) were constructed. Ultraviolet spectrophotometry revealed prolonged Res release (about 25%) from Pep-PP@Res in 48 h and fluorescent confocal microscopy showed the prolonged intracellular Res retention time of Pep-PP@Res (>24 h) in comparison with that of free Res (<4 h) and PP@Res (<4 h). MTT and EdU cell proliferation assays showed stronger suppressive effects of Pep-PP@Res on rat C6 GBM cells than that of PP@Res (p = 0.024) and Res (p = 0.009) when used twice for 4 h/day. Pep-PP@Res had little toxic effect on normal rat brain cells. The in vivo anti-glioblastoma effects of Res can be distinctly improved in the form of Pep-PP@Res nanoparticles via activating JNK signaling, upregulating proapoptosis gene expression and, finally, resulting in extensive apoptosis. Pep-PP@Res with sustained release and GBM-targeting properties would be suitable for in vivo management of GBMs.

Liver Cancer: New Insights into Surgical and Nonsurgical Treatments

Introduction:

Hepatocellular carcinoma (HCC) is the most common type of liver cancer that has increased in recent years worldwide. Primary liver cancer or HCC is considered the 5th and 7th most common cancer among men and women, respectively. It is also the second leading cause of cancer death worldwide. Unfortunately, HCC is frequently diagnosed at an advanced stage when the majority of the patients do not have access to remedial therapies. Furthermore, current systemic chemotherapy shows low efficacy and minimum survival benefits. Liver cancer therapy is a multidisciplinary, multiple-choice treatment based on the complex interaction of the tumour stage, the degree of liver disease, and the patient's general state of health.

Methods:

In this paper, we reviewed new insights into nonsurgical and surgical treatment of liver cancer in five English databases, including Scopus, PubMed, Web of Science, EMBASE, and Google Scholar up to December 2019.

Results:

The results demonstrated, in addition to current therapies such as chemotherapy and surgical resection, new approaches, including immunotherapy, viral therapy, gene therapy, new ablation therapies, and adjuvant therapy, are widely used for the treatment of HCC. In recent years, biomaterials such as nanoparticles, liposomes, microspheres, and nanofibers are also regarded as reliable and innovative patents for the treatment and study of liver cancers.

Conclusion:

Multidisciplinary and multi-choice treatments and therapies are available for this liver cancer, while there are differences in liver cancer management recommendations among specialties and geographic areas. Current results have shown that treatment strategies have been combined with the advancement of novel treatment modalities. In addition, the use of new approaches with greater efficacy, such as combination therapy, biomaterials, ablation therapy, etc. can be considered the preferred treatment for patients.

Biotinylated chitosan macromolecule based nanosystems: A review from chemical design to biological targets

World Health Organization estimates that 30-50% of cancers are preventable by healthy lifestyle choices, early detection and adequate therapy. When the conventional therapeutic strategies are still regulated by the lack of selectivity, multidrug resistance and severe toxic side effects, nanotechnology grants a new frontier for cancer management since it targets cancer cells and spares healthy tissues. This review highlights recent studies using biotin molecule combined with functional nanomaterials used in biomedical applications, with a particular attention on biotinylated chitosan-based nanosystems. Succinctly, this review focuses on five areas of recent advances in biotin engineering: (a) biotin features, (b) biotinylation approaches, (c) biotin functionalized chitosan based nanosystems for drug and gene delivery functions, (d) diagnostic and theranostic perspectives, and (e) author's inputs to the biotin-chitosan based tumour-targeting drug delivery structures. Precisely engineered biotinylated-chitosan macromolecules shaped into nanosystems are anticipated to emerge as next-generation platforms for treatment and molecular imaging modalities applications.

Reviewing Chitin/Chitosan Nanofibers and Associated Nanocomposites and Their Attained Medical Milestones

Chitin/chitosan research is an expanding field with wide scope within polymer research. This topic is highly inviting as chitin/chitosan's are natural biopolymers that can be recovered from food waste and hold high potentials for medical applications. This review gives a brief overview of the chitin/chitosan based nanomaterials, their preparation methods and their biomedical applications. Chitin nanofibers and Chitosan nanofibers have been reviewed, their fabrication methods presented and their biomedical applications summarized. The chitin/chitosan based nanocomposites have also been discussed. Chitin and chitosan nanofibers and their binary and ternary composites are represented by scattered superficial reports. Delving deep into synergistic approaches, bringing up novel chitin/chitosan nanocomposites, could help diligently deliver medical expectations. This review highlights such lacunae and further lapses in chitin related inputs towards medical applications. The grey areas and future outlook for aligning chitin/chitosan nanofiber research are outlined as research directions for the future.

Resveratrol-loaded nanomedicines for cancer applications

BACKGROUND

Resveratrol (3, 5, 4' -trihydroxystilbene), a natural polyphenol and phytoalexin, has drawn considerable attention in the past decade due to its wide variety of therapeutic activities such as anticancer, anti-inflammatory, and antioxidant properties. However, its poor water solubility, low chemical stability, and short biological half-life limit its clinical utility.

RECENT FINDINGS

Nanoparticles overcome the limitations associated with conventional chemotherapeutic drugs, such as limited availability of drugs to the tumor tissues, high systemic exposures, and consequent toxicity to healthy tissues. This review focuses on the physicochemical properties of resveratrol, the therapeutic potential of resveratrol nano-formulations, and the anticancer activity of resveratrol encapsulated nanoparticles on various malignancies such as skin, breast, prostate, colon, liver, ovarian, and lung cancers (focusing on both in vitro and in vivo studies).

CONCLUSIONS

Nanotechnology approaches have been extensively utilized to achieve higher solubility, improved oral bioavailability, enhanced stability, and controlled release of resveratrol. The resveratrol nanoparticles have markedly enhanced its anticancer activity both in vitro and in vivo, thus considering it as a potential strategy to fight various cancers.

In vitro and in vivo combinatorial anticancer effects of oxaliplatin- and resveratrol-loaded N,O-carboxymethyl chitosan nanoparticles against colorectal cancer

BACKGROUND

Oxaliplatin (OXE) combined with other chemotherapy drugs against colorectal cancer had been reported in the literature before, however, the efficacy of oxaliplatin combined with natural compounds was elusive. In addition, the clinical bioactivity and therapeutic dose of antitumor drugs are severely limited due to poor targeting and side effects. NDDSs offers an excellent strategy to overcome the disadvantages of small molecule anticancer drugs.

METHODS

Here, we have prepared N,O-carboxymethyl chitosan Oxaliplatin nanoparticles (CMCS-OXE NPs) and N,O-carboxymethyl chitosan Resveratrol nanoparticles (CMCS-Res NPs) were prepared by ion crosslinking and emulsification crosslinking, respectively.

RESULTS

The results revealed that the CMCS-OXE NPs exhibited a high encapsulation efficiency (60%) with a size of approximately 190.0 nm, and the CMCS-Res NPs exhibited a high encapsulation efficiency (65%) with a size of approximately 164.2 nm. The treatment with both types of nanoparticles combined exhibited more significant anti-colon cancer activity than the free drugs or either type of nanoparticle alone. In the in vivo experiments, the inhibition efficiency of the combined nanoparticle treatment was much stronger than the free drugs or either type of nanoparticle alone.

CONCLUSIONS

Overall, combination of oxaliplatin and resveratrol into a nanoparticle-drug delivery systems (NDDSs) appears to be a promising strategy for colorectal cancer (CRC) therapy.

Construction and evaluation of red blood cells-based drug delivery system for chemo-photothermal therapy

In this study, a novel tumor-targeting drug delivery system (DDS) based on red blood cells (RBCs) were fabricated for combinational chemo-phototherapy against cancer. Cyclic peptide (cRGD) and indocyanine green (ICG) were applied to the surface of RBCs to increase the targeting and photothermal effect, respectively. Doxorubicin (DOX) as a model drug was loaded into RBCs by the hypotonic dialysis method. A series of tests have been carried out to evaluate the RBCs-based DDS and these tasks include physicochemical properties, cellular uptake, targeting ability, and combination therapeutic efficiency. As a result, the DOX was successfully loaded into RBCs and the drug loading amount was 0.84 ± 0.09 mg/mL. There was no significant change of particle size after surface modification of RBCs. The RBCs-based DDS could target to the surface of cancer cells, which delivery DOX to the lesions efficiently and accurately. Meanwhile, due to the combined treatment effect, the RBCs-based DDS can effectively inhibit tumor growth. The RBCs-based DDS constructed in this research may have promising applications in cancer therapy due to their highly synergistic efficient therapy and to investigate its possibility for tumor therapy.

Antioxidant and C5a-blocking strategy for hepatic ischemia-reperfusion injury repair

BACKGROUND

Nonspecific liver uptake of nanomaterials after intravenous injection has hindered nanomedicine for clinical translation. However, nanomaterials' propensity for liver distribution might enable their use in hepatic ischemia-reperfusion injury (IRI) repair. During hepatic IRI, reactive oxygen species (ROS) are generated and the fifth component of complement (C5a) is activated. In addition, C5a is confirmed to exacerbate the vicious cycle of oxidative stress and inflammatory damage. For these reasons, we have investigated the development of nanomaterials with liver uptake to scavenge ROS and block C5a for hepatic IRI repair.

RESULTS

To achieve this goal, a traditional nanoantioxidant of nanoceria was surface conjugated with the anti-C5a aptamers (Ceria@Apt) to scavenge the ROS and reduce C5a-mediated inflammation. High uptake of Ceria@Apt in the liver was confirmed by preclinical positron emission tomography (PET) imaging. The clinical symptoms of hepatic IRI were effectively alleviated by Ceria@Apt with ROS scavenging and C5a blocking in mice model. The released pro-inflammatory cytokines were significantly reduced, and subsequent inflammatory reaction involved in the liver was inhibited.

CONCLUSIONS

The synthesized Ceria@Apt has great potential of medical application in hepatic IRI repair, which could also be applied for other ischemic-related diseases.

Antibody-mediated drug delivery

Passive and active targeted nanoparticulate delivery systems show promise to compensate for lacking properties of conventional therapy such as side effects, insufficient efficiency and accumulation of the drug at target site, poor pharmacokinetic properties etc. For active targeting, physically or covalently conjugated ligands, including monoclonal antibodies and their fragments, are consistently used and researched for targeting delivery systems or drugs to their target site. Currently, there are several FDA approved actively targeted antibody-drug conjugates, whereas no active targeted delivery system is in clinical use at present. However, efforts to successfully formulate actively targeted delivery systems continue. The scope of this review will be the use of monoclonal antibodies and their fragments as targeting ligands. General information about targeted delivery and antibodies will be given at the first half of the review. As for the second half, fragmentation of antibodies and conjugation approaches will be explained. Monoclonal antibodies and their fragments as targeting ligands and approaches for conjugating these ligands to nanoparticulate delivery systems and drugs will be the main focus of this review, polyclonal antibodies will not be included.

Designing biotin-human serum albumin nanoparticles to enhance the targeting ability of binuclear ruthenium(III) compound

On the one hand, to obtain a novel next-generation anticancer metal agent; on the other hand, to improve the targeting ability and decrease side effects of metal agent, we proposed to design active-targeting human serum albumin (HSA) nanoparticles (NPs) to achieve the end. Thus, we not only designed and synthesized two ruthenium (Ru) thiosemicarbazone compounds (C1 and C2) but also succeeded in constructing active Biotin-HSA NPs for Ru(III) compounds. Importantly, Biotin-HSA-C2 NPs not only possessed a stronger capacity for killing MCF-7 cells and inhibiting their migration versusC2 alone but also increased accumulation compared to non-malignant WI-38 cells. Additionally, C2 and Biotin-HSA-C2 NPs act against MCF-7 cells by the following potential mechanism: 1) arresting the cell cycle in the S phase by regulating cyclin and cyclin-dependent kinases; 2) inducing apoptosis by releasing cytochrome c to activate caspase-9/3; 3) inhibiting the expression of p-EGFR and regulating its neighboring cellular pathways, followed by the inactivation of PI3K/Akt and activation of p38 MAPK signaling pathways.

Plant-Derived Natural Products in Cancer Research: Extraction, Mechanism of Action, and Drug Formulation

Cancer is one of the main causes of death globally and considered as a major challenge for the public health system. The high toxicity and the lack of selectivity of conventional anticancer therapies make the search for alternative treatments a priority. In this review, we describe the main plant-derived natural products used as anticancer agents. Natural sources, extraction methods, anticancer mechanisms, clinical studies, and pharmaceutical formulation are discussed in this review. Studies covered by this review should provide a solid foundation for researchers and physicians to enhance basic and clinical research on developing alternative anticancer therapies.

Design, characterization, and intracellular trafficking of biofunctionalized chitosan nanomicelles

The hydrophobically modified glycol chitosan (HGC) nanomicelle has received increasing attention as a promising platform for the delivery of chemotherapeutic drugs. To improve the tumor selectivity of HGC, here an avidin and biotin functionalization strategy was applied. The hydrodynamic diameter of the biotin-avidin-functionalized HGC (cy5.5-HGC-B4F) was observed to be 104.7 nm, and the surface charge was +3.1 mV. Confocal and structured illumination microscopy showed that at 0.1 mg/ml, cy5.5-HGC-B4F nanomicelles were distributed throughout the cytoplasm of MDA-MB-231 breast cancer cells after 2 h of exposure without significant cytotoxicity. To better understand the intracellular fate of the nanomicelles, entrapment studies were performed and demonstrated that some cy5.5-HGC-B4F nanomicelles were capable of escaping endocytic vesicles, likely via the proton sponge effect. Quantitative analysis of the movements of endosomes in living cells revealed that the addition of HGC greatly enhanced the motility of endosomal compartments, and the nanomicelles were transported by early and late endosomes from cell periphery to the perinuclear region. Our results validate the importance of using live-cell imaging to quantitatively assess the dynamics and mechanisms underlying the complex endocytic pathways of nanosized drug carriers.

Chitosan Nanoparticles for Therapy and Theranostics of Hepatocellular Carcinoma (HCC) and Liver-Targeting

Chitosan nanoparticles are well-known delivery systems widely used as polymeric carriers in the field of nanomedicine. Chitosan is a carbohydrate of natural origin: it is a biodegradable, biocompatible, mucoadhesive, polycationic polymer and it is endowed with penetration enhancer properties. Furthermore, it can be easily derivatized. Hepatocellular carcinoma (HCC) represents a remarkable health problem because current therapies, that include surgery, liver transplantation, trans-arterial embolization, chemoembolization and chemotherapy, present significant limitations due to the high risk of recurrence, to a lack of drug selectivity and to other serious side effects. Therefore, there is the need for new therapeutic strategies and for improving the liver-targeting to HCC. Nanomedicine consists in the use of nanoscale carriers as delivery systems to target and deliver drugs and/or diagnostic agents to specific organs or tissues. Chitosan and its derivatives can be successfully used in the preparation of nanoparticles that, for their peculiar surface-properties, can specifically interact with liver tumor, by passive and active targeting. This review concerns the use of chitosan nanoparticles for the therapy and theranostics of HCC and liver-targeting.

Novel Drug Delivery Systems for Loading of Natural Plant Extracts and Their Biomedical Applications

Many types of research have distinctly addressed the efficacy of natural plant metabolites used for human consumption both in cell culture and preclinical animal model systems. However, these in vitro and in vivo effects have not been able to be translated for clinical use because of several factors such as inefficient systemic delivery and bioavailability of promising agents that significantly contribute to this disconnection. Over the past decades, extraordinary advances have been made successfully on the development of novel drug delivery systems for encapsulation of plant active metabolites including organic, inorganic and hybrid nanoparticles. The advanced formulas are confirmed to have extraordinary benefits over conventional and previously used systems in the manner of solubility, bioavailability, toxicity, pharmacological activity, stability, distribution, sustained delivery, and both physical and chemical degradation. The current review highlights the development of novel nanocarrier for plant active compounds, their method of preparation, type of active ingredients, and their biomedical applications.

Liver Cancer: Current and Future Trends Using Biomaterials

Hepatocellular carcinoma (HCC) is the fifth most common type of cancer diagnosed and the second leading cause of death worldwide. Despite advancement in current treatments for HCC, the prognosis for this cancer is still unfavorable. This comprehensive review article focuses on all the current technology that applies biomaterials to treat and study liver cancer, thus showing the versatility of biomaterials to be used as smart tools in this complex pathologic scenario. Specifically, after introducing the liver anatomy and pathology by focusing on the available treatments for HCC, this review summarizes the current biomaterial-based approaches for systemic delivery and implantable tools for locally administrating bioactive factors and provides a comprehensive discussion of the specific therapies and targeting agents to efficiently deliver those factors. This review also highlights the novel application of biomaterials to study HCC, which includes hydrogels and scaffolds to tissue engineer 3D in vitro models representative of the tumor environment. Such models will serve to better understand the tumor biology and investigate new therapies for HCC. Special focus is given to innovative approaches, e.g., combined delivery therapies, and to alternative approaches-e.g., cell capture-as promising future trends in the application of biomaterials to treat HCC.

Contemporary Formulations for Drug Delivery of Anticancer Bioactive Compounds

BACKGROUND

The immense development in the field of anticancer research has led to an increase in the research of bioactive compounds with anticancer potential. It has been known that many bioactive natural compounds have low solubility (and low bioavailability) as their main drawback when it comes to the formulation and drug delivery to specific sites.

OBJECTIVE

As many attempts have been made to overcome this issue, this review gives a summary of the current accomplishments regarding the development of new Drug Delivery Systems (DDSs) represented by nanoparticles (NPs) and exosomes.

METHODS

We analyzed the published data concerning selected compounds that present the most prominent plant secondary metabolites with anticancer potential, specifically flavone (quercetin), isoflavone (genistein and curcumin) and stilbene (resveratrol) groups that have been formulated as NPs and exosomes. In addition, we summarized the patent literature published from 2015-2018 that address these formulations.

RESULTS

Although the exact mechanism of action for the selected natural compounds still remains unclear, the anticancer effect is evident and the main research efforts are directed to finding the most suitable delivery systems. Recent patents in this field serve as evidence that these newly designed natural compound delivery systems could be powerful new anticancer agents in the very near future if the noted difficulties are overcome.

CONCLUSION

The focus of recent research is not only to clarify the exact mechanisms of action and therapeutic effects, but also to answer the issue of suitable delivery systems that can transport sufficient doses of bioactive compounds to the desired target.

Manufacture and Physicochemical Properties of Chitosan Oligosaccharide/A2 β-Casein Nano-Delivery System Entrapped with Resveratrol

The purposes of this research were to form chitosan oligosaccharide (CSO)/A2 β-casein nano-delivery systems (NDSs) and to investigate the effects of production variables, such as CSO concentration levels (0.1%, 0.2%, and 0.3%, w/v) and manufacturing temperature (5°C, 20°C, and 35°C), on the production and physicochemical characteristics of CSO/A2 β-casein NDSs to carry resveratrol. The morphological characteristics of CSO/A2 β-casein NDSs were assessed by the use of transmission electron microscopy (TEM) and particle size analyzer. High-performance liquid chromatography (HPLC) was applied to determine the entrapment efficiency (EE) of resveratrol. In the TEM images, globular-shaped particles with a diameter from 126 to 266 nm were examined implying that NDSs was successfully formed. As CSO concentration level was increased, the size and zeta-potential values of NDSs were significantly (p<0.05) increased. An increase in manufacturing temperature from 5°C to 35°C resulted in a significant (p<0.05) increase in the size and polydispersity index of NDSs. Over 85% of resveratrol was favorably entrapped in CSO/A2 β-casein NDSs. The entrapment efficiency (EE) of resveratrol was significantly (p<0.05) enhanced with an increase in manufacturing temperature while CSO concentration level did not significantly affect EE of resveratrol. There were no significant (p<0.05) changes observed in the size and polydispersity index of NDSs during heat treatments and storage in model milk and yogurt indicating that CSO/A2 β-casein NDSs exhibited excellent physical stability. In conclusion, the CSO concentration level and manufacturing temperature were the crucial determinants affecting the physicochemical characteristics of CSO/A2 β-casein NDSs containing resveratrol.

Synthesis, Bioapplications, and Toxicity Evaluation of Chitosan-Based Nanoparticles

The development of advanced nanomaterials and technologies is essential in biomedical engineering to improve the quality of life. Chitosan-based nanomaterials are on the forefront and attract wide interest due to their versatile physicochemical characteristics such as biodegradability, biocompatibility, and non-toxicity, which play a promising role in biological applications. Chitosan and its derivatives are employed in several applications including pharmaceuticals and biomedical engineering. This article presents a comprehensive overview of recent advances in chitosan derivatives and nanoparticle synthesis, as well as emerging applications in medicine, tissue engineering, drug delivery, gene therapy, and cancer therapy. In addition to the applications, we critically review the main concerns and mitigation strategies related to chitosan bactericidal properties, toxicity/safety using tissue cultures and animal models, and also their potential environmental impact. At the end of this review, we also provide some of future directions and conclusions that are important for expanding the field of biomedical applications of the chitosan nanoparticles.

Chitin/Chitosan: Versatile Ecological, Industrial, and Biomedical Applications

Chitin is a linear polysaccharide of N-acetylglucosamine, which is highly abundant in nature and mainly produced by marine crustaceans. Chitosan is obtained by hydrolytic deacetylation. Both polysaccharides are renewable resources, simply and cost-effectively extracted from waste material of fish industry, mainly crab and shrimp shells. Research over the past five decades has revealed that chitosan, in particular, possesses unique and useful characteristics such as chemical versatility, polyelectrolyte properties, gel- and film-forming ability, high adsorption capacity, antimicrobial and antioxidative properties, low toxicity, and biocompatibility and biodegradability features. A plethora of chemical chitosan derivatives have been synthesized yielding improved materials with suggested or effective applications in water treatment, biosensor engineering, agriculture, food processing and storage, textile additives, cosmetics fabrication, and in veterinary and human medicine. The number of studies in this research field has exploded particularly during the last two decades. Here, we review recent advances in utilizing chitosan and chitosan derivatives in different technical, agricultural, and biomedical fields.

Biotin functionalized PEGylated poly(amidoamine) dendrimer conjugate for active targeting of paclitaxel in cancer

In the current study, we employed poly(amidoamine) (PAMAM) dendrimers of generation 4 (G4) to deliver paclitaxel (PTX), a poorly soluble anti-cancer agent precisely to cancer cells via its conjugation on dendrimer surface. Further, G4 PAMAM has been PEGylated (PEG) and tagged with Biotin, an essential micronutrient for cellular functions, receptors of which are overexpressed in certain cancers. The synthesized multifunctional conjugates were characterized by ¹H NMR and zeta potential analysis techniques. In addition, the conjugates were evaluated in vitro in cell monolayers and 3D spheroids of biotin receptor over-expressed A549 cell line (human non-small cell lung cancer). G4 PTX PEG-Biotin conjugate penetrated at significantly higher extent in monolayers as well as spheroids as studied by flow cytometry and confocal microscopy by visualizing the cells at varied depth. The G4 PTX PEG-Biotin conjugate demonstrated higher cytotoxicity compared to free PTX and G4 PTX PEG conjugate as assessed by MTT assay in monolayers and Presto Blue assay in detached spheroidal cells. G4 PTX PEG-Biotin demonstrated significant inhibition of growth of tumor spheroids. Therefore, the newly synthesized biotin anchored PTX-conjugated dendrimer system is promising and could be further explored for efficiently delivering PTX to biotin receptor overexpressed cancers.

Resveratrol as a potential therapeutic drug for respiratory system diseases

Respiratory system diseases are common and major ailments that seriously endanger human health. Resveratrol, a polyphenolic phytoalexin, is considered an anti-inflammatory, antioxidant, and anticancer agent. Thanks to its wide range of biological activities, resveratrol has become a hotspot in many fields, including respiratory system diseases. Indeed, research has demonstrated that resveratrol is helpful to relieve pulmonary function in the general population. Meanwhile, growing evidence indicates that resveratrol plays a protective role in respiratory system diseases. This review aimed to summarize the main protective effects of resveratrol in respiratory system diseases, including its anti-inflammatory, antiapoptotic, antioxidant, antifibrotic, antihypertensive, and anticancer activities. We found that resveratrol plays a protective role in the respiratory system through a variety of mechanisms, and so it may become a new drug for the treatment of respiratory system diseases.

Chemically Edited Exosomes with Dual Ligand Purified by Microfluidic Device for Active Targeted Drug Delivery to Tumor Cells

Exosomes, which are lipid membrane-bound nanovesicles (50-150 nm in diameter), have aroused extensive attention for their potential applications in invasive molecular and stand for a new therapeutic delivery system. However, they are limited by poor targeting ability and a lack of efficient isolation techniques. Here, we present a three-dimensional nanostructured microfluidic chip, in which arrays of micropillars were functionalized with crisscrossed multiwall carbon nanotubes by chemical deposition, to capture exosomes with high efficiency through a combination of a specific recognition molecule (CD63) and the unique topography of the nanomaterials. As is proven, this nanostructured interface substantially made the immuno capturing of exosomes more efficient. A high percentage of intact vesicles <150 nm were readily purified. As a further application, we added functionality to the exosomes by a chemical editing approach for targeted drug delivery. Donor cells were labeled chemically with dual ligands (biotin and avidin) in the phospholipid membrane and encapsulated drugs in the cytosol. Though the engineered donor cells secreted exosomes, the dual ligands, together with the drugs, were inherited by the exosomes, which were then isolated with the microfluidic chip. Then, the isolated exosomes were used as drug delivery vehicles and showed strong targeting abilities to tumor cells and highly efficient receptor-mediated cellular uptake when exposed to recipient cells. Thus, the anticancer effect of chemotherapeutic drugs was improved significantly. It suggested that this platform could provide a useful tool for isolating intact exosomes with high efficiency and exploiting their natural carrier function to deliver chemotherapeutic drugs to tumor cells with increased efficacy and targeting capacity.

Anti-cancer efficacy of biotinylated chitosan nanoparticles in liver cancer

The present study investigated the synthesis of biotinylated chitosan (Bio-CS) from chitosan using a nanomaterial skeleton with biotin and the successful targeting of the formulation in liver cancer cells. Bio-CS was validated by fourier transformed infrared spectroscopy and hydrogen^-1 nuclear magnetic resonance spectroscopy. Bio-CS and plasmid DNA were used to construct Bio-CS/plasmid DNA nanoparticles according to the optimal molar ratio of 1:1 and the optimal pH-value of 5.5. Under these conditions, the parameters mean particle size, potential, encapsulation rate and drug loading, were 82.9 nm, +21.8 mV, 85.7% and 35.4%, respectively. Bio-CS exhibited an apparent liver cancer targeting effect in vitro and in vivo, as demonstrated by confocal laser scanning, green fluorescent protein transfection, and in vivo imaging assays. In addition, the Bio-CS/plasmid DNA nanoparticles significantly increased the survival period of the orthotropic liver cancer mouse model compared with the plasmid DNA, with no apparent side effects on the cells. Bio-CS nanomaterials stimulated an immune response in hepatoma cells via increased expression of GM-CSF, IL-21 and Rae-1 markers. The data suggest that Bio-CS increased the inhibition of liver cancer cell proliferation in vitro and the activation of the cellular immunity in vivo.

Nanoparticle formulations to enhance tumor targeting of poorly soluble polyphenols with potential anticancer properties

Polyphenols have been extensively studied for their relevant anticancer activity. Quite often however their instability, extensive metabolization, low bioavailability and poor solubility limit their application in cancer prevention and therapy. Formulation in nanoparticles has been widely proposed as a means to overcome these limits, maximize localization and specific activity at tumor site. The present review is intended as an update of literature regarding nanoparticulate carriers aimed to deliver polyphenols to the cancer site. Three molecules were chosen, all of which were hydrophobic and poorly soluble, representative of different polyphenol classes: quercetin (QT) among the flavonoid group, curcumin (CUR) as representative of curcuminoids, and resveratrol (RSV) among the stilbenes. In particular, nanoparticulate systems suitable for poorly soluble drugs will be described and attention will be paid to characteristics designed to improve tumor targeting, specific delivery and interaction with tumor cells.

Improving In Vivo Efficacy of Bioactive Molecules: An Overview of Potentially Antitumor Phytochemicals and Currently Available Lipid-Based Delivery Systems

Cancer is among the leading causes of morbidity and mortality worldwide. Many of the chemotherapeutic agents used in cancer treatment exhibit cell toxicity and display teratogenic effect on nontumor cells. Therefore, the search for alternative compounds which are effective against tumor cells but reduce toxicity against nontumor ones is of great importance in the progress or development of cancer treatments. In this sense, scientific knowledge about relevant aspects of nutrition intimately involved in the development and progression of cancer progresses rapidly. Phytochemicals, considered as bioactive ingredients present in plant products, have shown promising effects as potential therapeutic/preventive agents on cancer in several in vitro and in vivo assays. However, despite their bioactive properties, phytochemicals are still not commonly used in clinical practice due to several reasons, mainly attributed to their poor bioavailability. In this sense, new formulation strategies are proposed as carriers to improve their bioefficacy, highlighting the use of lipid-based delivery systems. Here, we review the potential antitumoral activity of the bioactive compounds derived from plants and the current studies carried out in animal and human models. Furthermore, their association with lipids as a formulation strategy to enhance their efficacy in vivo is also reported. The development of high effective bioactive supplements for cancer treatment based on the improvement of their bioavailability goes through this association.

The principles and applications of avidin-based nanoparticles in drug delivery and diagnosis

Avidin-biotin interaction is one of the strongest non-covalent interactions in the nature. Avidin and its analogues have therefore been extensively utilized as probes and affinity matrices for a wide variety of applications in biochemical assays, diagnosis, affinity purification, and drug delivery. Recently, there has been a growing interest in exploring this non-covalent interaction in nanoscale drug delivery systems for pharmaceutical agents, including small molecules, proteins, vaccines, monoclonal antibodies, and nucleic acids. Particularly, the ease of fabrication without losing the chemical and biological properties of the coupled moieties makes the avidin-biotin system a versatile platform for nanotechnology. In addition, avidin-based nanoparticles have been investigated as diagnostic systems for various tumors and surface antigens. In this review, we will highlight the various fabrication principles and biomedical applications of avidin-based nanoparticles in drug delivery and diagnosis. The structures and biochemical properties of avidin, biotin and their respective analogues will also be discussed.