Current update on nanoplatforms as therapeutic and diagnostic tools: A review for the materials used as nanotheranostics and imaging modalities

In the last decade, the use of nanotheranostics as emerging diagnostic and therapeutic tools for various diseases, especially cancer, is held great attention. Up to date, several approaches have been employed in order to develop smart nanotheranostics, which combine bioactive targeting on specific tissues as well as diagnostic properties. The nanotheranostics can deliver therapeutic agents by concomitantly monitor the therapy response in real-time. Consequently, the possibility of over- or under-dosing is decreased. Various non-invasive imaging techniques have been used to quantitatively monitor the drug delivery processes. Radiolabeling of nanomaterials is widely used as powerful diagnostic approach on nuclear medicine imaging. In fact, various radiolabeled nanomaterials have been designed and developed for imaging tumors and other lesions due to their efficient characteristics. Inorganic nanoparticles as gold, silver, silica based nanomaterials or organic nanoparticles as polymers, carbon based nanomaterials, liposomes have been reported as multifunctional nanotheranostics. In this review, the imaging modalities according to their use in various diseases are summarized, providing special details for radiolabeling. In further, the most current nanotheranostics categorized via the used nanomaterials are also summed up. To conclude, this review can be beneficial for medical and pharmaceutical society as well as material scientists who work in the field of nanotheranostics since they can use this research as guide for producing newer and more efficient nanotheranostics.

Epigenetics in Breast Cancer Therapy-New Strategies and Future Nanomedicine Perspectives

Epigenetic dysregulation has been recognized as a critical factor contributing to the development of resistance against standard chemotherapy and to breast cancer progression via epithelial-to-mesenchymal transition. Although the efficacy of the first-generation epigenetic drugs (epi-drugs) in solid tumor management has been disappointing, there is an increasing body of evidence showing that epigenome modulation, in synergy with other therapeutic approaches, could play an important role in cancer treatment, reversing acquired therapy resistance. However, the epigenetic therapy of solid malignancies is not straightforward. The emergence of nanotechnologies applied to medicine has brought new opportunities to advance the targeted delivery of epi-drugs while improving their stability and solubility, and minimizing off-target effects. Furthermore, the omics technologies, as powerful molecular epidemiology screening tools, enable new diagnostic and prognostic epigenetic biomarker identification, allowing for patient stratification and tailored management. In combination with new-generation epi-drugs, nanomedicine can help to overcome low therapeutic efficacy in treatment-resistant tumors. This review provides an overview of ongoing clinical trials focusing on combination therapies employing epi-drugs for breast cancer treatment and summarizes the latest nano-based targeted delivery approaches for epi-drugs. Moreover, it highlights the current limitations and obstacles associated with applying these experimental strategies in the clinics.

Nanotheranostic Carbon Dots as an Emerging Platform for Cancer Therapy

Cancer remains one of the most deadly diseases globally, but carbon-based nanomaterials have the potential to revolutionize cancer diagnosis and therapy. Advances in nanotechnology and a better understanding of tumor microenvironments have contributed to novel nanotargeting routes that may bring new hope to cancer patients. Several low-dimensional carbon-based nanomaterials have shown promising preclinical results; as such, low-dimensional carbon dots (CDs) and their derivatives are considered up-and-coming candidates for cancer treatment. The unique properties of carbon-based nanomaterials are high surface area to volume ratio, chemical inertness, biocompatibility, and low cytotoxicity. It makes them well suited for delivering chemotherapeutics in cancer treatment and diagnosis. Recent studies have shown that the CDs are potential applicants in biomedical sciences, both as nanocarriers and nanotransducers. This review covers the most commonly used CD nanoparticles in nanomedicines intended for the early diagnosis and therapy of cancer.

Barium Titanate (BaTiO3) Nanoparticles Exert Cytotoxicity through Oxidative Stress in Human Lung Carcinoma (A549) Cells

Barium titanate (BaTiO3) nanoparticles (BT NPs) have shown exceptional characteristics such as high dielectric constant and suitable ferro-, piezo-, and pyro-electric properties. Thus, BT NPs have shown potential to be applied in various fields including electro-optical devices and biomedicine. However, very limited knowledge is available on the interaction of BT NPs with human cells. This work was planned to study the interaction of BT NPs with human lung carcinoma (A549) cells. Results showed that BT NPs decreased cell viability in a dose- and time-dependent manner. Depletion of mitochondrial membrane potential and induction of caspase-3 and -9 enzyme activity were also observed following BT NP exposure. BT NPs further induced oxidative stress indicated by induction of pro-oxidants (reactive oxygen species and hydrogen peroxide) and reduction of antioxidants (glutathione and several antioxidant enzymes). Moreover, BT NP-induced cytotoxicity and oxidative stress were effectively abrogated by N-acetyl-cysteine (an ROS scavenger), suggesting that BT NP-induced cytotoxicity was mediated through oxidative stress. Intriguingly, the underlying mechanism of cytotoxicity of BT NPs was similar to the mode of action of ZnO NPs. At the end, we found that BT NPs did not affect the non-cancerous human lung fibroblasts (IMR-90). Altogether, BT NPs selectively induced cytotoxicity in A549 cells via oxidative stress. This work warrants further research on selective cytotoxicity mechanisms of BT NPs in different types of cancer cells and their normal counterparts.

Exploring Diffusion and Cellular Uptake: Charged Gold Nanoparticles in an in Vitro Breast Cancer Model

Gold nanoparticles have emerged as a prominent tool in nanomedicine, particularly for applications in cancer diagnostic and treatment. One of the challenges for the successful implementation of gold nanoparticles in cancer therapy is their delivery to the specific cancer area within the tumor microenvironment. The presence of cancer enables a poorly organized vascularization system, increasing the pressure with the microenvironment, limiting the uptake of particles. The physicochemical properties of the gold nanoparticles (size, shape, and surface charge) also have a significant effect on diffusion to the tumor site and cellular uptake. In this work, we analyzed the transport of 10 nm gold nanoparticles with different surface charges (neutral, negative, and positive) through a hydrogel composite. Three-dimensional in vitro models composed of breast cancer cells loaded in the hydrogel composite were used for the qualitative and quantitative evaluation of cellular uptake of the gold nanoparticles. Surprisingly, an inverse correlation between the diffusion coefficients of the nanoparticles and cellular uptake was demonstrated. Positively charged gold nanoparticles displayed high cellular uptake, although their diffusion coefficient indicated slow transport through the hydrogel matrix. Neutral particles, on the other hand, displayed fast diffusion but the lowest cellular uptake. The results obtained indicate that nanoparticle diffusion and cellular uptake should be studied together in realistic in vitro models for a true evaluation of transport in tumor microenvironments.

The role of single- and multi-walled carbon nanotube in breast cancer treatment

Numerous studies have been conducted to design new strategies for breast cancer treatment. Past studies have shown a wide range of carbon-nanomaterials properties, such as single- and multi-walled carbon nanotubes (SWCNTs and MWCNTs) in breast cancer diagnosis and treatment. In this regard, the current study aims to review the role of both SWCNTs and MWCNTs in breast cancer treatment and diagnosis. For reaching this goal, we reviewed the literature by using various searching engines such as Scopus, PubMed, Google Scholar, Web of Science and MEDLINE. This comprehensive review showed that CNTs could dramatically improve breast cancer treatment and could be used as a novel modality to increase diagnostic accuracy; however, no clinical studies have been conducted based on CNTs. In addition, the literature review demonstrates a lack of enough studies to evaluate the side effects of using CNTs.

A structurally diverse library of glycerol monooleate/oleic acid non-lamellar liquid crystalline nanodispersions stabilized with nonionic methoxypoly(ethylene glycol) (mPEG)-lipids showing variable complement activation properties

Pluronic F127-stabilized non-lamellar liquid crystalline aqueous nanodispersions are promising injectable platforms for drug and contrast agent delivery. These nanodispersions, however, trigger complement activation in the human blood, where the extent of complement activation and opsonization processes may compromise their biological performance and safety. Here, we introduce a broad family of nanodispersions from glycerol monooleate (GMO) and oleic acid (OA) in different weight ratios, and stabilized with a plethora of nonionic methoxypoly(ethylene glycol) (mPEG)-lipids of different PEG chain length and variable lipid moiety (monounsaturated or saturated diglycerides or D-α-tocopheryl succinate). Through an integrated biophysical approach involving dynamic light scattering, synchrotron small-angle scattering, and cryo-transmission electron microscopy, we examine the impact of nonionic mPEG-lipid stabilization on size, internal self-assembled architecture, and gross morphological characteristics of nanodispersions. The results show how the nonionic mPEG-lipid type and concentration, and dependent on GMO/OA weight ratio, can variably modulate the internal architectures of nanoparticles. Assessment of complement profiling from selected nanodispersions with diverse structural heterogeneity further suggests a variable modulatory role for the lipid type of the nonionic mPEG-lipid in the extent of complement activation, which span from no activation to moderate to high levels. We comment on plausible mechanisms driving the observed complement activation variability and discuss the potential utility of these nanodispersions for future development of injectable nanopharmaceuticals.

In situ monitoring of the formation of lipidic non-lamellar liquid crystalline depot formulations in synovial fluid

Administration of parenteral liquid crystalline phases, forming in-vivo with tunable nanostructural features and sustained release properties, offers an attractive approach for treatment of infections and local drug delivery. It has also a potential use for postoperative pain management after arthroscopic knee surgery. However, the optimal use of this drug delivery principle requires an improved understanding of the involved dynamic structural transitions after administration of low-viscous stimulus-responsive lipid precursors and their fate after direct contact with the biological environment. These precursors (preformulations) are typically based on a single biologically relevant lipid (or a lipid combination) with non-lamellar liquid crystalline phase forming propensity. In relation to liquid crystalline depot design for intra-articular drug delivery, it was our interest in the present study to shed light on such dynamic structural transitions by combining synchrotron SAXS with a remote controlled addition of synovial fluid (or buffer containing 2% (w/v) albumin). This combination allowed for monitoring in real-time the hydration-triggered dynamic structural events on exposure of the lipid precursor (organic stock solution consisting of the binary lipid mixture of monoolein and castor oil) to excess synovial fluid (or excess buffer). The synchrotron SAXS findings indicate a fast generation of inverse bicontinuous cubic phases within few seconds. The effects of (i) the organic solvent N-methyl-2-pyrolidone (NMP), (ii) the lipid composition, and (iii) the albumin content on modulating the structures of the self-assembled lipid aggregates and the implications of the experimental findings in the design of liquid crystalline depots for intra-articular drug delivery are discussed.

Anticancer Potential of Furanocoumarins: Mechanistic and Therapeutic Aspects

Cancer is one of the most extreme medical conditions in both developing and developed countries around the world, causing millions of deaths each year. Chemotherapy and/or radiotherapy are key for treatment approaches, but both have numerous adverse health effects. Furthermore, the resistance of cancerous cells to anticancer medication leads to treatment failure. The rising burden of cancer overall requires novel efficacious treatment modalities. Natural medications offer feasible alternative options against malignancy in contrast to western medication. Furanocoumarins' defensive and restorative impacts have been observed in leukemia, glioma, breast, lung, renal, liver, colon, cervical, ovarian, and prostate malignancies. Experimental findings have shown that furanocoumarins activate multiple signaling pathways, leading to apoptosis, autophagy, antioxidant, antimetastatic, and cell cycle arrest in malignant cells. Additionally, furanocoumarins have been shown to have chemo preventive and chemotherapeutic synergistic potential when used in combination with other anticancer drugs. Here, we address different pathways which are activated by furanocoumarins and their therapeutic efficacy in various tumors. Ideally, this review will trigger interest in furanocoumarins and their potential efficacy and safety as a cancer lessening agents.

Gambogic acid: A shining natural compound to nanomedicine for cancer therapeutics

The United States Food and Drug Administration has permitted number of therapeutic agents for cancer treatment. Most of them are expensive and have some degree of systemic toxicity which makes overbearing in clinical settings. Although advanced research continuously applied in cancer therapeutics, but drug resistance, metastasis, and recurrence remain unanswerable. These accounts to an urgent clinical need to discover natural compounds with precisely safe and highly efficient for the cancer prevention and cancer therapy. Gambogic acid (GA) is the principle bioactive and caged xanthone component, a brownish gamboge resin secreted from the of Garcinia hanburyi tree. This molecule showed a spectrum of biological and clinical benefits against various cancers. In this review, we document distinct biological characteristics of GA as a novel anti-cancer agent. This review also delineates specific molecular mechanism(s) of GA that are involved in anti-cancer, anti-metastasis, anti-angiogenesis, and chemo-/radiation sensitizer activities. Furthermore, recent evidence, development, and implementation of various nanoformulations of gambogic acid (nanomedicine) have been described.

Breast cancer: Biology, biomarkers, and treatments

During the past recent years, various therapies emerged in the era of breast cancer. Breast cancer is a heterogeneous disease in which genetic and environmental factors are involved. Breast cancer stem cells (BCSCs) are the main player in the aggressiveness of different tumors and also, these cells are the main challenge in cancer treatment. Moreover, the major obstacle to achieve an effective treatment is resistance to therapies. There are various types of treatment for breast cancer (BC) patients. Therefore, in this review, we present the current treatments, novel approaches such as antibody-drug conjugation systems (ADCs), nanoparticles (albumin-, metal-, lipid-, polymer-, micelle-based nanoparticles), and BCSCs-based therapies. Furthermore, prognostic and predictive biomarkers will be discussed also biomarkers that have been applied by some tests such as Oncotype DX, Mamm αPrint, and uPA/PAI-1 are regarded as suitable prognostic and predictive factors in breast cancer.

Anti-tumor effect of PEG-coated PLGA nanoparticles of febuxostat on A549 non-small cell lung cancer cells

In the present study, febuxostat (FBX)-loaded PEG-coated PLGA nanoparticles (FBX-PLGA-PEG) were developed and its anticancer activity on lung cancer cells was evaluated. FBX-PLGA-PEG were prepared by nanoprecipitation technique and characterized for particle size, size distribution, entrapment efficiency, and in vitro drug release study. The optimized formulations were used to evaluate cell viability, apoptosis, cell cycle, and caspase activity in A549 lung cancer cells. The optimized formulation showed spherical particle with average particle size of 180 ± 4.72 nm, particle-size distribution 0.223 ± 0.003, entrapment efficiency (70 ± 2.56%), and drug release (99.1 ± 2.33%) at 12 h. MTT cytotoxicity assay showed better cytotoxic potential of FBX-NPs than FBX solution against NSCLC A549 cells. The lower IC50 of FBX-NP (52.62 ± 2.52 µg/mL) compared to FBX (68.0 ± 4.12 µg/mL) are suggestive of a potential cytotoxic effect of nano-formulation compared to the drug itself. Furthermore, flow cytometry analysis showed significantly higher percentage of total apoptotic cells in FBX-NPs (10.38 ± 1.57%) as compared to FBX solution (2.76 ± 0.17%) showed strong proapoptotic potential of FBX nano-formulation. The increased caspase activity and percent of cells at G2/M phase of cell cycle increased for FBX nanoparticles were more effective than FBX solution in increasing caspase activity and percent of cells at G2/M phase of cell cycle. Our studies with FBX nanoparticles exhibited promising outcome which could be used as a strategies to combat lung cancer.

The versatile biomedical applications of bismuth-based nanoparticles and composites: therapeutic, diagnostic, biosensing, and regenerative properties

Studies of nanosized forms of bismuth (Bi)-containing materials have recently expanded from optical, chemical, electronic, and engineering fields towards biomedicine, as a result of their safety, cost-effective fabrication processes, large surface area, high stability, and high versatility in terms of shape, size, and porosity. Bi, as a nontoxic and inexpensive diamagnetic heavy metal, has been used for the fabrication of various nanoparticles (NPs) with unique structural, physicochemical, and compositional features to combine various properties, such as a favourably high X-ray attenuation coefficient and near-infrared (NIR) absorbance, excellent light-to-heat conversion efficiency, and a long circulation half-life. These features have rendered bismuth-containing nanoparticles (BiNPs) with desirable performance for combined cancer therapy, photothermal and radiation therapy (RT), multimodal imaging, theranostics, drug delivery, biosensing, and tissue engineering. Bismuth oxyhalides (BiO_x, where X is Cl, Br or I) and bismuth chalcogenides, including bismuth oxide, bismuth sulfide, bismuth selenide, and bismuth telluride, have been heavily investigated for therapeutic purposes. The pharmacokinetics of these BiNPs can be easily improved via the facile modification of their surfaces with biocompatible polymers and proteins, resulting in enhanced colloidal stability, extended blood circulation, and reduced toxicity. Desirable antibacterial effects, bone regeneration potential, and tumor growth suppression under NIR laser radiation are the main biomedical research areas involving BiNPs that have opened up a new paradigm for their future clinical translation. This review emphasizes the synthesis and state-of-the-art progress related to the biomedical applications of BiNPs with different structures, sizes, and compositions. Furthermore, a comprehensive discussion focusing on challenges and future opportunities is presented.

Non-Lamellar Liquid Crystalline Nanocarriers for Thymoquinone Encapsulation

Owing to their unique structural features, non-lamellar liquid crystalline nanoparticles comprising cubosomes and hexosomes are attracting increasing attention as versatile investigative drug carriers. Background: Depending on their physiochemical characteristics, drug molecules on entrapment can modulate and reorganize structural features of cubosomes and hexosomes. Therefore, it is important to assess the effect of guest molecules on broader biophysical characteristics of non-lamellar liquid crystalline nanoparticles, since drug-induced architectural, morphological, and size modifications can affect the biological performance of cubosomes and hexosomes. Methods: We report on alterations in morphological, structural, and size characteristics of nanodispersions composed from binary mixtures of glycerol monooleate and vitamin E on thymoquinone (a molecule with wide therapeutic potentials) loading. Results: Thymoquinone loading was associated with a slight increase in the mean hydrodynamic nanoparticle size and led to structural transitions from an internal biphasic feature of coexisting inverse cubic Fd3m and hexagonal (H₂) phases to an internal inverse cubic Fd3m phase (micellar cubosomes) or an internal inverse micellar (L₂) phase (emulsified microemulsions, EMEs). We further report on the presence of “flower-like” vesicular populations in both native and drug-loaded nanodispersions. Conclusions: These nanodispersions have the potential to accommodate thymoquinone and may be considered as promising platforms for the development of thymoquinone nanomedicines.

Internal Lamellar and Inverse Hexagonal Liquid Crystalline Phases During the Digestion of Krill and Astaxanthin Oil-in-Water Emulsions

Krill oil represents an important alternative natural source of omega-3 (ω-3) polyunsaturated fatty acids (PUFAs). Considering the beneficial health effects of these essential fatty acids, particularly in various disorders including cancer, cardiovascular, and inflammation diseases, it is of paramount importance to gain insight into the digestibility of krill oil. In this work, we study the fate of krill oil-in-water emulsion, stabilized by sodium caseinate, during lipolysis by coupling time-resolved synchrotron small-angle X-ray scattering (SAXS) to flow-through lipolysis model. For gaining further insight into the effect of ω-3 PUFA-containing oil type on the dynamic structural features occurring during lipolysis, two additional astaxanthin oil-in-water emulsions, stabilized using either sodium caseinate or citrem, were subjected to lipolysis under identical experimental conditions. In addition to the difference in lipid composition in both oils, ω-3 PUFAs in astaxanthin oil, similar to fish oil, exist in the form of triacylglycerols; whereas most of those in krill oil are bound to phospholipids. SAXS showed the formation of highly ordered nanostructures on exposure of these food emulsions to the lipolysis medium: the detection of a biphasic feature of coexisting inverse hexagonal (H₂) and lamellar (L_α) liquid crystalline phases in the digested krill oil droplets' interiors, as compared to a neat L_α phase in the digested astaxanthin oil droplets. We discuss the dynamic phase behavior and describe the suggested important role of these phases in facilitating the delivery of nutrients throughout the body. In addition, the potential implication in the development of food and drug nanocarriers is briefly described.

pH Responsiveness of Hexosomes and Cubosomes for Combined Delivery of Brucea javanica Oil and Doxorubicin

We report pH-responsive liquid crystalline lipid nanoparticles, which are dual-loaded by Brucea javanica oil (BJO) and doxorubicin hydrochloride (DOX) and display a pH-induced inverted hexagonal (pH = 7.4) to cubic (pH = 6.8) to emulsified microemulsion (pH = 5.3) phase transition with a therapeutic application in cancer inhibition. BJO is a traditional herbal medicine that strongly inhibits the proliferation and metastasis of various cancers. Doxorubicin is an antitumor drug, which prevents DNA replication and hampers protein synthesis through intercalation between the base pairs of the DNA helices. Its dose-dependent cardiotoxicity imposes the need for safe delivery carriers. Here, pH-induced changes in the structural and interfacial properties of designed multicomponent drug delivery (monoolein-oleic acid-BJO-DOX) systems are determined by synchrotron small-angle X-ray scattering and the Langmuir film balance technique. The nanocarrier assemblies display good physical stability in the studied pH range and adequate particle sizes and ζ-potentials. Their interaction with model lipid membrane interfaces is enhanced under acidic pH conditions, which mimic the microenvironment around tumor cells. In vitro cytotoxicity and apoptosis studies with BJO-DOX dual-loaded pH-switchable liquid crystalline nanoparticles are performed on the human breast cancer Michigan Cancer Foundation-7 (MCF-7) cell line and MCF-7 cells with doxorubicin resistance (MCF-7/DOX), respectively. The obtained pH-sensitive nanomedicines exhibit enhanced antitumor efficacy. The performed preliminary studies suggest a potential reversal of the resistance of the MCF-7/DOX cells to DOX. These results highlight the necessity for further understanding the link between the established pH-dependent drug release profiles of the nanocarriers and the role of their pH-switchable inverted hexagonal, bicontinuous cubic, and emulsified microemulsion inner organizations for therapeutic outcomes.

X-Ray Characterization of Pharmaceutical and Cosmetic Lipidic Nanoparticles for Cutaneous Application

Starting from the second half of the 1900s, the advent of nanotechnology in medicine has provoked a profound revolution in this area; at present, nanomedicine delivered a remarkably large set of research and clinically useful tools as diagnostic devices, contrast agents, analytical tools, physical therapy applications, and drugdelivery vehicles. Concerning nanoformulations for drug delivery, they are constituted by nanoparticles with dimensions lower than 1 μm, usually characterized by improved pharmacokinetics, taking advantage of specific targeting, and reduced side effects. The contributors to the present chapter are reviewing a range of papers related to the structural characterization of nanoformulations by X-ray diffraction techniques. The whole of the considered papers underlines the essential role that biophysical techniques have acquired as an essential prerequisite to understanding stability, bioavailability, and lipid, biopolymer, and drug organization in nanoformulations.

Benefits of Nanomedicine for Therapeutic Intervention in Malignant Diseases

Cancer remains one of the most difficult to manage healthcare problems. The last two decades have been considered the golden age of cancer research, with major breakthroughs being announced on a regular basis. However, the major problem regarding cancer treatment is the incapability to selectively target cancer cells, with certain populations of tumors still remaining alive after treatment. The main focus of researchers is to develop treatments that are both effective and selective in targeting malignant cells. In this regard, bioavailability can be increased by overcoming the biological barriers encountered in the active agent’s pathway, creating carrier vehicles that have the ability to target malignant cells and effectively release the active agent. Since its appearance, nanomedicine has provided many answers to these challenges, but still, some expectations were not satisfied. In this review, we focused on the most recent developments in targeted drug delivery. Furthermore, a summary of different types of nanoparticles used to deliver active therapeutic agents in oncology is presented, along with details on the nanodrugs that were clinically approved by the Food and Drug Administration (FDA), until April 2019.

Liposomes of Quantum Dots Configured for Passive and Active Delivery to Tumor Tissue

The majority of developed and approved anticancer nanomedicines have been designed to exploit the dogma of the enhanced permeability and retention (EPR) effect, which is based on the leakiness of the tumor's blood vessels accompanied by impeded lymphatic drainage. However, the EPR effect has been under scrutiny recently because of its variable manifestation across tumor types and animal species and its poor translation to human cancer therapy. To facilitate the EPR effect, systemically injected NPs should overcome the obstacle of rapid recognition and elimination by the mononuclear phagocyte system (MPS). We hypothesized that circulating monocytes, major cells of the MPS that infiltrate the tumor, may serve as an alternative method for achieving increased tumor accumulation of NPs, independent of the EPR effect. We describe here the accumulation of liposomal quantum dots (LipQDs) designed for active delivery via monocytes, in comparison to LipQDs designed for passive delivery (via the EPR effect), following IV administration in a mammary carcinoma model. Hydrophilic QDs were synthesized and entrapped in functionalized liposomes, conferring passive ("stealth" NPs; PEGylated, neutral charge) and active (monocyte-mediated delivery; positively charged) properties by differing in their lipid composition, membrane PEGylation, and charge (positively, negatively, and neutrally charged). The various physicochemical parameters affecting the entrapment yield and optical stability were examined in vitro and in vivo. Biodistribution in the blood, various organs, and in the tumor was determined by the fluorescence intensity and Cd analyses. Following the treatment of animals (intact and mammary-carcinoma-bearing mice) with disparate formulations of LipQDs (differing by their lipid composition, neutrally and positively charged surfaces, and hydrophilic membrane), we demonstrate comparable tumor uptake of QDs delivered by the passive and the active routes (mainly by Ly-6C^hi monocytes). Our findings suggest that entrapping QDs in nanosized liposomal formulations, prepared by a new facile method, imparts superior structural and optical stability and a suitable biodistribution profile leading to increased tumor uptake of fluorescently stable QDs.

Nanomaterials multifunctional behavior for enlightened cancer therapeutics

Cancer is an outrageous disease with uncontrolled differentiation, growth, and migration to the other parts of the body. It is the second-most common cause of death both in the U.S. and worldwide. Current conventional therapies, though much improved and with better prognosis, have several limitations. Chemotherapeutic agents, for instance, are cytotoxic to both tumor and healthy cells, and the non-specific distribution of drugs at tumor sites limits the dose administered. Nanotechnology, which evolved from the coalescence and union of varied scientific disciplines, is a novel science that has been the focus of much research. This technology is generating more effective cancer therapies to overcome biomedical and biophysical barriers against standard interventions in the body; its unique magnetic, electrical, and structural properties make it a promising tool. This article reviews endogenous- and exogenous-based stimulus-responsive drug delivery systems designed to overcome the limitations of conventional therapies. The article also summarizes the study of nanomaterials, including polymeric, gold, silver, magnetic, and quantum dot nanoparticles. Though an array of drug delivery systems has so far been proposed, there remain many challenges and concerns that should be addressed in order to fill the gaps in the field. Prominence is given to drug delivery systems that employ external- and internal-based stimuli and that are emerging as promising tools for cancer therapeutics in clinical settings.

MicroRNA Biogenesis is Enhanced by Liposome-Encapsulated Pin1 Inhibitor in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is in an urgent need of new, effective therapies to reduce morbidity and mortality. We have previously demonstrated that peptidyl-prolyl cis/trans isomerase Pin1 is a potential target for HCC therapy, due to its pivotal role in HCC development through regulating miRNA biogenesis, and discovered the small molecule API-1 as a novel and specific Pin1 inhibitor. Despite its significant anti-HCC activity, the low water solubility and in vivo bioavailability of API-1 limit its clinical application. To address these issues, we herein developed a liposomal formulation of API-1 to improve API-1 delivery and enhance its anti-HCC efficacy. Methods: We designed and developed a nanoscale liposomal formulation of API-1, named as API-LP. Subsequently, the mean diameter, polydispersity, zeta potential, encapsulation efficiency and thermal properties of the optimization API-LP were characterized. The enhanced anti-HCC activity and the molecular mechanism of API-LP were investigated both in vitro and in vivo. Finally, the safety and pharmacokinetic property of API-LP were evaluated systematically. Results: API-LP had good formulation characteristics and exhibited an enhanced in vitro activity of suppressing proliferation and migration of HCC cells when compared with free API-1. The mechanism study showed that API-LP upregulated miRNA biogenesis via inhibiting Pin1 activity followed by restoring the nucleus-to-cytoplasm export of XPO5. Because of the increased delivery efficiency, API-LP displayed a stronger ability to promote miRNA biogenesis than free API-1. Importantly, API-LP displayed higher systemic exposure than free API-1 in mice without apparent toxicity, resulting in an enhanced tumor inhibition in xenograft mice. Conclusion: The development and assessment of API-LP provide an attractive and safe anti-HCC agent, highlighting the miRNA-based treatment for human cancers.

pH-Responsive Nano-Self-Assemblies of the Anticancer Drug 2-Hydroxyoleic Acid

pH-responsive lipid nanocarriers have the potential to selectively target the acidic extracellular pH environment of cancer tissues and may further improve the efficacy of chemotherapeutics by minimizing their toxic side-effects. Here, we present the design and characterization of pH-sensitive nano-self-assemblies of the poorly water-soluble anticancer drug 2-hydroxyoleic acid (2OHOA) with glycerol monooleate (GMO). pH-triggered nanostructural transformations from 2OHOA/GMO nanoparticles with an internal inverse hexagonal structure (hexosomes) at pH around 2.0-3.0, via nanocarriers with an internal inverse bicontinuous cubic structure (cubosomes) at pH 2.0-4.5, to vesicles at pH 4.5-7.4 were observed with synchrotron small-angle X-ray scattering, and cryogenic transmission electron microscopy. ζ-potential measurements highlight that the pH-driven deprotonation of the carboxylic group of 2OHOA, and the resulting charge-repulsions at the lipid-water interface account for these nanostructural alterations. The study provides detailed insight into the pH-dependent self-assembly of 2OHOA with GMO in excess buffer at physiologically relevant pH values, and discusses the effects of pH alterations on modulating their nanostructure. The results may guide the further development of pH-responsive anticancer nanocarriers for the targeted delivery of chemotherapeutics to the local microenvironment of tumor cells.

A hydrodynamic flow focusing microfluidic device for the continuous production of hexosomes based on docosahexaenoic acid monoglyceride

Cubosomes and hexosomes are emerging platforms for drug and nutraceutical delivery applications. In addition to common high- and low-energy batch emulsification methods for the preparation of these nano-self-assemblies, it is important to introduce suitable microfluidic devices with a precision control of the flow parameters for their continuous production. Microfluidics has several advantages including cost effectiveness, short-production time, and control of the nanoparticle size and size distribution. In the present study, a hydrodynamic flow focusing polyimide microfluidic device was employed for the continuous production of hexosomes based on docosahexaenoic acid monoglyceride (MAG-DHA), in the presence of the stabilizer Pluronic F127. The size, structural, morphological and size characterizations of the continuously produced MAG-DHA nanodispersions were investigated through an integrated approach involving synchrotron small angle X-ray scattering, dynamic light scattering, and cryogenic transmission electron microscopy. We report on a simple process for the microfluidic synthesis of hexosomes with sizes ranging from 108 to 138 nm and relatively narrow size distributions as the polydispersity indices were in the range of 0.14-0.22. At the applied total volumetric flow rates (TFRs) ranging of 50-150 μL min^-1 and flow rate ratios (FRRs) of 10-30, it was evident from SAXS findings that ethanol has only a slight effect on the lattice parameter of the internal inverse hexagonal (H₂) phase of the produced hexosomes. In addition to hexosomes, cryo-TEM observations indicated the coexistence of vesicular structures and smaller nano-objects. The formation of these nano-objects that are most likely normal micelles was also confirmed by SAXS, particularly on increasing FRR from 10 to 20 or 30 at TFR of 150 μL min^-1. Taking into account the reported positive health effects of MAG-DHA, which is a long-chain omega-3 (ω-3) polyunsaturated fatty acid (PUFA) monoglyceride, in various disorders including cancer, the produced hexosomes are attractive for the delivery of ω-3 PUFAs, drugs, nutraceuticals, and their combinations.

Lipid-Based Nanoparticles: Application and Recent Advances in Cancer Treatment

Many therapeutically active molecules are non-soluble in aqueous systems, chemically and biologically fragile or present severe side effects. Lipid-based nanoparticle (LBNP) systems represent one of the most promising colloidal carriers for bioactive organic molecules. Their current application in oncology has revolutionized cancer treatment by improving the antitumor activity of several chemotherapeutic agents. LBNPs advantages include high temporal and thermal stability, high loading capacity, ease of preparation, low production costs, and large-scale industrial production since they can be prepared from natural sources. Moreover, the association of chemotherapeutic agents with lipid nanoparticles reduces active therapeutic dose and toxicity, decreases drug resistance and increases drug levels in tumor tissue by decreasing them in healthy tissue. LBNPs have been extensively assayed in in vitro cancer therapy but also in vivo, with promising results in some clinical trials. This review summarizes the types of LBNPs that have been developed in recent years and the main results when applied in cancer treatment, including essential assays in patients.