A Smart Paclitaxel-Disulfiram Nanococrystals for Efficient MDR Reversal and Enhanced Apoptosis

Disulfiram: A novel repurposed drug for cancer therapy

ABSTRACT

Cancer is a major global health issue. Effective therapeutic strategies can prolong patients' survival and reduce the costs of treatment. Drug repurposing, which identifies new therapeutic uses for approved drugs, is a promising approach with the advantages of reducing research costs, shortening development time, and increasing efficiency and safety. Disulfiram (DSF), a Food and Drug Administration (FDA)-approved drug used to treat chronic alcoholism, has a great potential as an anticancer drug by targeting diverse human malignancies. Several studies show the antitumor effects of DSF, particularly the combination of DSF and copper (DSF/Cu), on a wide range of cancers such as glioblastoma (GBM), breast cancer, liver cancer, pancreatic cancer, and melanoma. In this review, we summarize the antitumor mechanisms of DSF/Cu, including induction of intracellular reactive oxygen species (ROS) and various cell death signaling pathways, and inhibition of proteasome activity, as well as inhibition of nuclear factor-kappa B (NF-κB) signaling. Furthermore, we highlight the ability of DSF/Cu to target cancer stem cells (CSCs), which provides a new approach to prevent tumor recurrence and metastasis. Strikingly, DSF/Cu inhibits several molecular targets associated with drug resistance, and therefore it is becoming a novel option to increase the sensitivity of chemo-resistant and radio-resistant patients. Studies of DSF/Cu may shed light on its improved application to clinical tumor treatment.

Nanomedicine-based disulfiram and metal ion co-delivery strategies for cancer treatment

Disulfiram (DSF) is a second-line drug for the clinical treatment of alcoholism and has long been proven to be safe for use in clinical practice. In recent years, researchers have discovered the cancer-killing activity of DSF, which is highly dependent on the presence of metal ions, particularly copper ions. Additionally, free DSF is highly unstable and easily degraded within few minutes in blood circulation. Therefore, an ideal DSF formulation should facilitate the co-delivery of metal ions and safeguard the DSF throughout its biological journey before reaching the targeted site. Extensive research have proved that nanotechnology based formulations can effectively realize this goal by strategic encapsulation therapeutic agents within nanoparticle. To be more specific, this is accomplished through precise delivery, coordinated release of metal ions at the tumor site, thereby amplifying its cytotoxic potential. Beyond traditional co-loading techniques, innovative approaches such as DSF-metal complex and metal nanomaterials, have also demonstrated promising results at the animal model stage. This review aims to elucidate the anticancer mechanism associated with DSF and its reliance on metal ions, as well as to provide a comprehensive overview of recent advances in the arena of nanomedicine based co-delivery strategies for DSF and metal ion in the context of cancer therapy.

Better together: nanoscale co-delivery systems of therapeutic agents for high-performance cancer therapy

Combination therapies can enhance the sensitivity of cancer to drugs, lower drug doses, and reduce side effects in cancer treatment. However, differences in the physicochemical properties and pharmacokinetics of different therapeutic agents limit their application. To avoid the above dilemma and achieve accurate control of the synergetic ratio, a nanoscale co-delivery system (NCDS) has emerged as a prospective tool for combined therapy in cancer treatment, which is increasingly being used to co-load different therapeutic agents. In this study, we have summarized the mechanisms of therapeutic agents in combination for cancer therapy, nanoscale carriers for co-delivery, drug-loading strategies, and controlled/targeted co-delivery systems, aiming to give a general picture of these powerful approaches for future NCDS research studies.

Schiff bases and their metal complexes to target and overcome (multidrug) resistance in cancer

Overcoming multidrug resistance (MDR) is one of the major challenges in cancer therapy. In this respect, Schiff base-related compounds (bearing a R1R2CNR3 bond) gained high interest during the past decades. Schiff bases are considered privileged ligands for various reasons, including the easiness of their preparation and the possibility to form complexes with almost all transition metal ions. Schiff bases and their metal complexes exhibit many types of biological activities and are used for the treatment and diagnosis of various diseases. Until now, 13 Schiff bases have been investigated in clinical trials for cancer treatment and hypoxia imaging. This review represents the first collection of Schiff bases and their complexes which demonstrated MDR-reversal activity. The areas of drug resistance covered in this article involve: 1) Modulation of ABC transporter function, 2) Targeting lysosomal ABCB1 overexpression, 3) Circumvention of ABC transporter-mediated drug efflux by alternative routes of drug uptake, 4) Selective activity against MDR cancer models (collateral sensitivity), 5) Targeting GSH-detoxifying systems, 6) Overcoming apoptosis resistance by inducing necrosis and paraptosis, 7) Reactivation of mutated p53, 8) Restoration of sensitivity to DNA-damaging anticancer therapy, and 9) Overcoming drug resistance through modulation of the immune system. Through this approach, we would like to draw attention to Schiff bases and their metal complexes representing highly interesting anticancer drug candidates with the ability to overcome MDR.

Nanocrystal technologies in biomedical science: From the bench to the clinic

The pharmaceutical industry is grappling with a pressing crisis in drug development characterized by soaring R&D costs, setbacks in blockbuster drug development due to poor aqueous solubility, and patent-related limitations on newly approved molecules. To combat these challenges, diverse strategies have emerged to enhance the solubility and dissolution rates of Biopharmaceutics Classification System (BCS) II and IV drug molecules. Enter drug nanocrystals, a revolutionary nanotechnology-driven, carrier-free colloidal drug delivery system. This review provides a comprehensive insight into nanocrystal strategies, stabilizer selection criteria, preparation methods, advanced characterization techniques, the evolving nanocrystal technological landscape, current market options, and exciting clinical prospects for reshaping the future of pharmaceuticals.

The immunomodulatory function and antitumor effect of disulfiram: paving the way for novel cancer therapeutics

More than 60 years ago, disulfiram (DSF) was employed for the management of alcohol addiction. This promising cancer therapeutic agent inhibits proliferation, migration, and invasion of malignant tumor cells. Furthermore, divalent copper ions can enhance the antitumor effects of DSF. Molecular structure, pharmacokinetics, signaling pathways, mechanisms of action and current clinical results of DSF are summarized here. Additionally, our attention is directed towards the immunomodulatory properties of DSF and we explore novel administration methods that may address the limitations associated with antitumor treatments based on DSF. Despite the promising potential of these various delivery methods for utilizing DSF as an effective anticancer agent, further investigation is essential in order to extensively evaluate the safety and efficacy of these delivery systems.

Targeted delivery of paclitaxel drug using polymer-coated magnetic nanoparticles for fibrosarcoma therapy: in vitro and in vivo studies

Fibrosarcoma is a rare type of cancer that affects cells known as fibroblasts that are malignant, locally recurring, and spreading tumor in fibrous tissue. In this work, an iron plate immersed in an aqueous solution of double added deionized water, supplemented with potassium permanganate solution (KMnO₄) was carried out by the pulsed laser ablation in liquid method (PLAIL). Superparamagnetic iron oxide nanoparticles (SPIONs) were synthesized using different laser wavelengths (1064, 532, and 266 nm) at a fluence of 28 J/cm² with 100 shots of the iron plate to control the concentration, shape and size of the prepared high-stability SPIONs. The drug nanocarrier was synthesized by coating SPION with paclitaxel (PTX)-loaded chitosan (Cs) and polyethylene glycol (PEG). This nanosystem was functionalized by receptors that target folate (FA). The physiochemical characteristics of SPION@Cs-PTX-PEG-FA nanoparticles were evaluated and confirmed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-Ray diffraction (XRD), atomic force microscopy (AFM), and dynamic light scattering (DLS) methods. Cell internalization, cytotoxicity assay (MTT), apoptosis induction, and gene expression of SPION@Cs-PTX-PEG-FA were estimated in fibrosarcoma cell lines, respectively. In vivo studies used BALB/c tumor-bearing mice. The results showed that SPION@Cs-PTX-PEG-FA exhibited suitable physical stability, spherical shape, desirable size, and charge. SPION@Cs-PTX-PEG-FA inhibited proliferation and induced apoptosis of cancer cells (P < 0.01). The results of the in vivo study showed that SPION@Cs-PTX-PEG-FA significantly decreased tumor size compared to free PTX and control samples (P < 0.05), leading to longer survival, significantly increased splenocyte proliferation and IFN-γ level, and significantly decreased the level of IL-4. All of these findings indicated the potential of SPION@Cs-PTX-PEG-FA as an antitumor therapeutic agent.

Co-crystal nanoarchitectonics as an emerging strategy in attenuating cancer: Fundamentals and applications

Cancer ranks as the second foremost cause of death in various corners of the globe. The clinical uses of assorted anticancer therapeutics have been limited owing to the poor physicochemical attributes, pharmacokinetic performance, and lethal toxicities. Various sorts of co-crystals or nano co-crystals or co-crystals-laden nanocarriers have presented great promise in targeting cancer via improved physicochemical attributes, pharmacokinetic performance, and reduced toxicities. These systems have also demonstrated the controlled cargo release and passive targeting via enhanced permeation and retention (EPR) effect. In addition, regional delivery of co-crystals via inhalation and transdermal route displayed remarkable potential in targeting lung and skin cancer effectively. However, more research is required on the use of co-crystals in cancer and their commercialization. The present review mainly emphasizes co-crystals as emerging avenues in the treatment of various cancers by modulating the physicochemical and pharmacokinetic attributes of approved anticancer therapeutics. The worth of co-crystals in cancer treatment, computational paths in the co-crystals screening, diverse experimental techniques of co-crystals fabrication, and sorts of co-crystals and their noteworthy applications in targeting cancer are also discussed. Besides, the game changer approaches like nano co-crystals and co-crystals-laden nanocarriers, and co-crystals in regional delivery in cancer are also explained with reported case studies. Furthermore, regulatory directives for pharmaceutical co-crystals and their scale-up, and challenges are also highlighted with concluding remarks and future initiatives. In essence, co-crystals and nano co-crystals emerge to be a promising strategy in overwhelming cancers through improving anticancer efficacy, safety, patient compliance, and reducing the cost.

A multifunctional theranostics nanosystem featuring self-assembly of alcohol-abuse drug and photosensitizers for synergistic cancer therapy

Conventional treatments for cancer, such as chemotherapy, surgical resection, and radiotherapy, have shown limited therapeutic efficacy, with severe side effects, lack of targeting and drug resistance for monotherapies, which limit their clinical application. Therefore, combinatorial strategies have been widely investigated in the battle against cancer. Herein, we fabricated a dual-targeted nanoscale drug delivery system based on EpCAM aptamer- and lactic acid-modified low-polyamidoamine dendrimers to co-deliver the FDA-approved agent disulfiram and photosensitizer indocyanine green, combining the imaging and therapeutic functions in a single platform. The multifunctional nanoparticles with uniform size had high drug-loading payload, sustained release, as well as excellent photothermal conversion. The integrated nanoplatform showed a superior synergistic effect in vitro and possessed precise spatial delivery to HepG2 cells with the dual-targeting nanocarrier. Intriguingly, a robust anticancer response of chemo-phototherapy was achieved; chemotherapy combined with the efficacy of phototherapy to cause cellular apoptosis of HepG2 cells (>35%) and inhibit the regrowth of damaged cells. Furthermore, the theranostic nanosystem displayed fluorescence imaging in vivo, attributed to its splendid accumulation in the tumor site, and it provided exceptional tumor inhibition rate against liver cancer cells (>76%). Overall, our research presents a promising multifunctional theranostic nanoplatform for the development of synergistic therapeutics for tumors in further applications.

Disulfiram: A Food and Drug Administration-approved multifunctional role in synergistically drug delivery systems for tumor treatment

Disulfiram (DSF), a Food and Drug Administration (FDA)-approved drug for the treatment of alcoholism, has been found to have antitumor activity. DSF showed better antitumor efficiency when it was used in combination with certain antitumor drugs. DSF plays an important role in cancer treatment. It has been used as multidrug resistance (MDR) modulator to reverse MDR and can also combine with copper ions (Cu²⁺), which will produce copper diethyldithiocarbamate (Cu[DDC]₂) complex with antitumor activity. The synergistic targeted drug delivery for cancer treatment based on DSF, especially the combination with exogenous Cu²⁺ and its forms of administration, has attracted extensive attention in the biomedical field. In this review, we summarize these synergistic delivery systems, in the hope that they will contribute to the continuous optimization and development of more advanced drug delivery systems. Furthermore, we discuss the current limitation and future directions of DSF-based drug delivery systems in the field of tumor therapy. Hopefully, our work may inspire further innovation of DSF-based antitumor drug delivery systems.

Nano- and Crystal Engineering Approaches in the Development of Therapeutic Agents for Neoplastic Diseases

Cancer is a leading cause of death worldwide. It is a global quandary that requires the administration of many different active pharmaceutical ingredients (APIs) with different characteristics. As is the case with many APIs, cancer treatments exhibit poor aqueous solubility which can lead to low drug absorption, increased doses, and subsequently poor bioavailability and the occurrence of more adverse events. Several strategies have been envisaged to overcome this drawback, specifically for the treatment of neoplastic diseases. These include crystal engineering, in which new crystal structures are formed to improve drug physicochemical properties, and/or nanoengineering in which the reduction in particle size of the pristine crystal results in much improved physicochemical properties. Co-crystals, which are supramolecular complexes that comprise of an API and a co-crystal former (CCF) held together by non-covalent interactions in crystal lattice, have been developed to improve the performance of some anti-cancer drugs. Similarly, nanosizing through the formation of nanocrystals and, in some cases, the use of both crystal and nanoengineering to obtain nano co-crystals (NCC) have been used to increase the solubility as well as overall performance of many anticancer drugs. The formulation process of both micron and sub-micron crystalline formulations for the treatment of cancers makes use of relatively simple techniques and minimal amounts of excipients aside from stabilizers and co-formers. The flexibility of these crystalline formulations with regards to routes of administration and ability to target neoplastic tissue makes them ideal strategies for effectiveness of cancer treatments. In this review, we describe the use of crystalline formulations for the treatment of various neoplastic diseases. In addition, this review attempts to highlight the gaps in the current translation of these potential treatments into authorized medicines for use in clinical practice.

Repurposing disulfiram as a chemo-therapeutic sensitizer: molecular targets and mechanisms

Currently, chemo-therapy is still the main strategy for cancer treatment. However, chemo-therapy resistance remains its main challenge. Disulfiram [DSF] is a drug approved by FDA for the treatment of alcohol addiction, but it is later discovered that it has the anticancer activity. Importantly, there have been many literatures reporting that DSF can be used as a chemo-therapeutic sensitizer to enhance the anticancer activity of chemo-drugs in a variety of cancers. Furthermore, the combinations of DSF and chemo-drugs have been tested in clinic trials. In the review, we summarized the possible molecular targets and mechanisms of DSF to reverse chemo-resistance. We also further discussed the opportunities and challenges of DSF as a chemo-therapeutic sensitizer. In conclusion, DSF could be a potential repurposed drug to sensitize cancer cells to chemo-therapy in clinic.

Recent Progress in Nanostructured Smart Drug Delivery Systems for Cancer Therapy: A Review

Traditional treatment approaches for cancer involve intravenous chemotherapy or other forms of drug delivery. These therapeutic measures suffer from several limitations such as nonspecific targeting, poor biodistribution, and buildup of drug resistances. However, significant technological advancements have been made in terms of superior modes of drug delivery over the last few decades. Technical capability in analyzing the molecular mechanisms of tumor biology, nanotechnology─particularly the development of biocompatible nanoparticles, surface modification techniques, microelectronics, and material sciences─has increased. As a result, a significant number of nanostructured carriers that can deliver drugs to specific cancerous sites with high efficiency have been developed. This particular maneuver that enables the introduction of a therapeutic nanostructured substance in the body by controlling the rate, time, and place is defined as the nanostructured drug delivery system (NDDS). Because of their versatility and ability to incorporate features such as specific targeting, water solubility, stability, biocompatibility, degradability, and ability to reverse drug resistance, they have attracted the interest of the scientific community, in general, and nanotechnologists as well as biomedical scientists. To keep pace with the rapid advancement of nanotechnology, specific technical aspects of the recent NDDSs and their prospects need to be reported coherently. To address these ongoing issues, this review article provides an overview of different NDDSs such as lipids, polymers, and inorganic nanoparticles. In addition, this review also reports the challenges of current NDDSs and points out the prospective research directions of these nanocarriers. From our focused review, we conclude that still now the most advanced and potent field of application for NDDSs is lipid-based, while other significantly potential fields include polymer-based and inorganic NDDSs. However, despite the promises, challenges remain in practical implementations of such NDDSs in terms of dosage and stability, and caution should be exercised regarding biocompatibility of materials. Considering these aspects objectively, this review on NDDSs will be particularly of interest for small-to-large scale industrial researchers and academicians with expertise in drug delivery, cancer research, and nanotechnology.

Leveraging disulfiram to treat cancer: Mechanisms of action, delivery strategies, and treatment regimens

Disulfiram (DSF) has been used as an alcoholism drug for 70 years. Recently, it has attracted increasing attention owing to the distinguished anticancer activity, which can be further potentiated by the supplementation of Cu²⁺. Although encouraging anticancer results are obtained in lab, the clinical outcomes of oral DSF are not satisfactory, which urges an in-depth understanding of the underlying mechanisms, bottlenecks, and proposal of potential methods to address the dilemma. In this review, a critical summarization of various molecular biological anticancer mechanisms of DSF/Cu²⁺ is provided and the predicament of orally delivering DSF in clinical oncotherapy is explained by the metabolic barriers. We highlight the recent advances in the DSF/Cu²⁺ delivery strategies and the emerging treatment regimens for cancer treatment. Last but not the least, we summarize the clinical trials regarding DSF and make a prospect of DSF/Cu-based cancer therapy.

Gut microbial dysbiosis and its association with esophageal cancer

Due to its aggressive nature and low survival rate, esophageal cancer is one of the deadliest cancer. While the intestinal microbiome significantly influences human health and disease. This research aimed to investigate and characterize the relative abundance of intestinal bacterial composition in esophageal cancer patients. The fecal samples were collected from esophageal cancer patients (n = 15) and healthy volunteers (n = 10). The PCR-DGGE was carried out by focusing on the V3 region of the 16S rRNA gene, and qPCR was performed for Bacteroides vulgatus, Escherichia coli, Bifidobacterium, Clostridium leptum and Lactobacillus. High-throughput sequencing of the 16S rRNA gene targeting the V3+V4 region was performed on 20 randomly selected samples. PCR-DGGE and High-throughput diversity results showed a significant alteration of gut bacterial composition between the experimental and control groups, which indicates the gut microbial dysbiosis in esophageal cancer patients. At the phylum level, there was significant enrichment of Bacteroidetes, while a non-significant decrease of Firmicutes in the experimental group. At family statistics, a significantly higher level of Bacteroidaceae and Enterobacteriaceae, while a significantly lower abundance of Prevotellaceae and Veillonellaceae were observed. There was a significantly high prevalence of genera Bacteroides, Escherichia-Shigella, while a significantly lower abundance of Prevotella_9 and Dialister in the experimental group as compared to the control group. Furthermore, the species analysis also showed significantly raised level of Bacteroides vulgatus and Escherichia coli in the experimental group. These findings revealed a significant gut microbial dysbiosis in esophageal cancer patients. So, the current study can be used for the understanding of esophageal cancer treatment, disease pathway, mechanism, and probiotic development.

Design of ultra-fine carvedilol nanococrystals: Development of a safe and stable injectable formulation

Carvedilol (CAR) is a strategic beta-blocker agent which its application has been limited by its very low water solubility. The present study describes a soluble form of drug based on nano-cocrystal (NCC) anti-solvent precipitation technique. The COSMOquick software was employed to select the optimum coformer (tartaric acid, TA) and organic solvent (acetone) relying on the enthalpy changes of cocrystallization and solubilization. Central Composite Design (CCD) considering the impact of CAR, TA, poloxamer 188 (stabilizer) concentrations, and anti-solvent/solvent ratio on CAR NCCs particle size (PS) could produce ultra-fine NCCs (about 1 nm). The lyophilization of NCCs investigating slow/fast freezing rates, various types and concentrations of cryprotectants and lyoprotectants indicated that PEG and trehalose (5 % w/vconcentration) under slow freezing rate could re-produce the initial PSs successfully. CAR NCCs indicated about 2000 fold increase in solubility compared with pure CAR. DSC and PXRD experiments proved that the formulations containing trehalose led to more crystalline and the ones comprising PEG led to more amorphous structures. Interestingly, the slow freezed PEG protected NCCs were physically stable for at least 18 months. In conclusion, the NCC technology could produce the first safe soluble form of CAR for treating hypertension urgencies easy for industrial scale-up.

Delivery strategies of amphotericin B for invasive fungal infections

Invasive fungal infections (IFIs) represent a growing public concern for clinicians to manage in many medical settings, with substantial associated morbidities and mortalities. Among many current therapeutic options for the treatment of IFIs, amphotericin B (AmB) is the most frequently used drug. AmB is considered as a first-line drug in the clinic that has strong antifungal activity and less resistance. In this review, we summarized the most promising research efforts on nanocarriers for AmB delivery and highlighted their efficacy and safety for treating IFIs. We have also discussed the mechanism of actions of AmB, rationale for treating IFIs, and recent advances in formulating AmB for clinical use. Finally, this review discusses some practical considerations and provides recommendations for future studies in applying AmB for combating IFIs.

Cocrystal engineering of pharmaceutical solids: therapeutic potential and challenges

This highlight presents an overview of pharmaceutical cocrystal production and its potential in reviving problematic properties of drugs in different dosage forms. The challenges and future outlook of its translational development are discussed.

Homotype-Targeted Biogenic Nanoparticles to Kill Multidrug-Resistant Cancer Cells

“Off-targeting” and receptor density expressed at the target sites always compromise the efficacy of the nanoparticle-based drug delivery systems. In this study, we isolated different cell membranes and constructed cell membrane-cloaked biogenic nanoparticles for co-delivery of antitumor paclitaxel (PTX) and multidrug resistance (MDR)-modulator disulfiram (DSF). Consequently, MDR cancer cell membrane (A549/T)-coated hybrid nanoparticles (A549/T CM-HNPs) selectively recognized the source cells and increased the uptake by ninefold via the homotypic binding mechanism. Moreover, the A549/T CM-HNPs sensitized MDR cells to PTX by suppressing P-glycoprotein (P-gp) activity by 3.2-fold and induced effective apoptosis (70%) in homologous A549/T cells. Cell-membrane coating based on the “homotypic binding” is promising in terms of promoting the accumulation of chemotherapeutics in MDR cells and killing them.

Repurposing Disulfiram as An Anti-Cancer Agent: Updated Review on Literature and Patents

BACKGROUND

Despite years of success of most anti-cancer drugs, one of the major clinical problems is inherent and acquired resistance to these drugs. Overcoming the drug resistance or developing new drugs would offer promising strategies in cancer treatment. Disulfiram, a drug currently used in the treatment of chronic alcoholism, has been found to have anti-cancer activity.

OBJECTIVE

To summarize the anti-cancer effects of Disulfiram through a thorough patent review.

METHODS

This article reviews molecular mechanisms and recent patents of Disulfiram in cancer therapy.

RESULTS

Several anti-cancer mechanisms of Disulfiram have been proposed, including triggering oxidative stress by the generation of reactive oxygen species, inhibition of the superoxide dismutase activity, suppression of the ubiquitin-proteasome system, and activation of the mitogen-activated protein kinase pathway. In addition, Disulfiram can reverse the resistance to chemotherapeutic drugs by inhibiting the P-glycoprotein multidrug efflux pump and suppressing the activation of NF-kB, both of which play an important role in the development of drug resistance. Furthermore, Disulfiram has been found to reduce angiogenesis because of its metal chelating properties as well as its ability to inactivate Cu/Zn superoxide dismutase and matrix metalloproteinases. Disulfiram has also been shown to inhibit the proteasomes, DNA topoisomerases, DNA methyltransferase, glutathione S-transferase P1, and O6- methylguanine DNA methyltransferase, a DNA repair protein highly expressed in brain tumors. The patents described in this review demonstrate that Disulfiram is useful as an anti-cancer drug.

CONCLUSION

For years the FDA-approved, well-tolerated, inexpensive, orally-administered drug Disulfiram was used in the treatment of chronic alcoholism, but it has recently demonstrated anti-cancer effects in a range of solid and hematological malignancies. Its combination with copper at clinically relevant concentrations might overcome the resistance of many anti-cancer drugs in vitro, in vivo, and in patients.

Old wine in new bottles: Advanced drug delivery systems for disulfiram-based cancer therapy

Disulfiram (DSF) is an FDA-approved drug that has been repurposed for cancer treatment. It showed excellent anticancer efficacy in combination with copper ions (Cu). Several active clinical trials testing the anticancer efficacy of DSF against various cancers are underway. In this review article, we summarized different delivery strategies for DSF-based cancer therapy. In many studies, DSF and Cu were delivered in two separate formulations. DSF and Cu formed copper diethyldithiocarbamate [Cu(DDC)₂] complex which was reported as a major active anticancer ingredient for DSF/Cu combination therapy. Various delivery systems for DSF and Cu were developed to enhance their delivery into tumors. The administration of preformed Cu(DDC)₂ complex was also explored to achieve better anticancer efficacy. Several studies developed formulations that were capable of delivering Cu(DDC)₂ complex in a single formulation. These novel formulations will address drug delivery challenges and have great potential to improve the efficacy of DSF-based cancer therapy. DSF is an off-patent drug molecule. The novel drug formulations of DSF will also serve as a good strategy for developing intellectual properties which will be critical for product development and commercialization.

Approaches to Targeting Cancer Stem Cells in Solid Tumors

CSCs are a population of self-renewing and tumor repopulating cells that have been observed in hematologic and solid tumors and their presence contributes to the development of drug resistance. The failure to eliminate CSCs with conventional therapy is one of major obstacles in the successful treatment of cancer. Several mechanisms have been described to contribute to CSCs chemoresistance properties that include the adoption of drug-efflux pumps, drug detoxification pathways, changes in metabolism, improved DNA repair mechanisms, and deregulated survival and pro-apoptotic pathways. Thus, CSCs are therefore an attractive target to develop new anti-cancer therapies.

Recent advances in the delivery of disulfiram: a critical analysis of promising approaches to improve its pharmacokinetic profile and anticancer efficacy

BACKGROUND

Disulfiram (DSF) has a long history of being used as a first-line promising therapy for treatment of alcoholism in human. Besides its prominence in the treatment of alcoholism, extensive investigations have been carried out to explore other biomedical and pharmacological effects of DSF. Amongst other biomedical implications, plenty researches have shown evidence of promising anticancer efficacy of this agent for treatment of wide range of cancers such as breast cancer, liver cancer and lung carcinoma.

METHODS

Electronic databases, including Google scholar, PubMed and Web of science were searched with the keywords disulfiram, nanoparticles, cancer, drug delivery systems.

RESULT

Despite its excellent anticancer efficacy, the pharmaceutical significance and clinical applicability of DSF are hampered due to poor stability, low solubility, short plasma half-life, rapid metabolism, and early clearance from systemic circulation. Various attempts have been made to eradicate these issues. Nanotechnology based interventions have gained remarkable recognition in improving pharmacokinetic and pharmacodynamic profile of DSF by improving its stability and avoiding its degradation.

CONCLUSION

The aim of the present review is to critically analyse all recent developments in designing various nanotechnology-based delivery systems, to ponder their relevance in improving stability, pharmacokinetic and pharmacodynamic profile, and achieving target-specific delivery of this agent to cancer cells to effectively eradicate cancer and abolish its metastasis. Nanotechnology is a novel approach for overcoming such obstacles faced presently, the results obtained so far using different novel drug delivery systems seem to be very promising to increase the stability and half-life of DSF. Graphical abstract Nanocrrier mediated drug delivery systems for disulfiram.

Advances in nanomedicine for the treatment of ankylosing spondylitis

Ankylosing spondylitis (AS) is a complex disease characterized by inflammation and ankylosis primarily at the cartilage–bone interface. The disease is more common in young males and risk factors include both genetic and environmental. While the pathogenesis of AS is not completely understood, it is thought to be an immune-mediated disease involving inflammatory cellular infiltrates, and human leukocyte antigen-B27. Currently, there is no specific diagnostic technique available for this disease; therefore conventional diagnostic approaches such as clinical symptoms, laboratory tests and imaging techniques are used. There are various review papers that have been published on conventional treatment approaches, and in this review work, we focus on the more promising nanomedicine-based treatment modalities to move this field forward.

Drug Nanorod-Mediated Intracellular Delivery of microRNA-101 for Self-sensitization via Autophagy Inhibition

Autophagy is closely related to the drug resistance and metastasis in cancer therapy. Nanoparticle-mediated co-delivery of combinatorial therapy with small-molecular drugs and nucleic acids is promising to address drug resistance. Here, a drug-delivering-drug (DDD) platform consisting of anti-tumor-drug nanorods as a vehicle for cytosol delivery of nucleic acid (miR-101) with potent autophagic-inhibition activity is reported for combinatorial therapy. The developed 180-nm nanoplatform, with total drug loading of up to 66%, delivers miR-101 to cancer cells, with threefold increase in intracellular level compared to conventional gene carriers and inhibits the autophagy significantly, along with above twofold reduction in LC3II mRNA and approximately fivefold increase in p62 mRNA over the control demonstrated in the results in vivo. And in turn, the delivery of miR-101 potentiates the drug's ability to kill cancer cells, with a threefold increase in apoptosis over that of chemotherapy alone. The anti-tumor study in vivo indicates the combined therapy that enables a reduction of 80% in tumor volume and > twofold increase in apoptosis than of the single-drug strategy. In summary, via the carrier-free strategy of DDD, this work provides a delivery platform that can be easily customized to overcome drug resistance and facilitates the delivery of combined therapy of small-molecular drugs and nucleic acids.

Drug nanocrystals: Fabrication methods and promising therapeutic applications

The drug nanocrystals (NCs) with unique physicochemical properties are now considered as a promising drug delivery system for poorly water-soluble drugs. So far >20 formulations of NCs have been approved in the market. In this review, we summarized recent advances of NCs with emphasis on their therapeutic applications based on administration route and disease states. At the end, we present a brief description of the future perspectives of NCs and their potential role as a promising drug delivery system. As a strategy for solubilization and bioavailability enhancement, the NCs have gained significant success. Besides this, the function of NCs is still far from developed. The emerging NC-based drug delivery approach would widen the applications of NCs in drug delivery and bio-medical field. Their in vitro and in vivo fate is extremely unclear; and the development of hybrid NCs with environment-sensitive fluorophores may assist to extend the scope of bio-imaging and provide better insight to their intracellular uptake kinetics, in vitro and in vivo.

Drug-delivering-drug approach-based codelivery of paclitaxel and disulfiram for treating multidrug-resistant cancer

Multidrug resistance (MDR) is a common intractable barrier in success of clinical cancer chemotherapy. Codelivery of two drugs using nanocarriers is a commonly used approach to treat the MDR cancer. However, the drug payload in the conventional nanocarriers is low and thus compromises the treatment outcomes. Disulfiram (DSF) is promising to reverse MDR and increases the sensitivity of cancer cells to chemotherapy. While, paclitaxel (PTX) is one of the frequently used anticancer drug. Here, by using a drug-delivering-drug (DDD) strategy based on nanocrystals, hybrid PTX-DSF nanocrystals (PTX-DSF Ns) were developed for codelivery of PTX and DSF to reverse MDR in cancer. The 160-nm PTX-DSF Ns with rod-like morphology had drug-loading up to 43% at mass ratio of 5:1. Interestingly, the nanoparticles entered cells via caveolar endocytosis. By reducing intracellular ATP level and GST activity, PTX-DSF Ns killed the Taxol resistant A549 cells with higher efficiency than PTX alone, exhibiting as 6-fold increase of apoptosis in MDR tumor. The nanoparticles circulated in blood over time, accumulated in tumor efficiently and reduced the tumor volume by 12-fold in MDR tumor-bearing BALB/c nude mice and allowed 12-fold apoptosis in tumor. Additionally, the immunohistochemical examination demonstrated the safety of the nanoparticles. Overall, the DDD strategy-based PTX-DSF Ns have promising potential for the treatment of MDR cancer.

Phytocosmeceutical formulation development, characterization and its in-vivo investigations

Several plants found rich in flavonoid, polyphenols, and antioxidants reported antiaging, oppose inflammation and carcinogenic properties but have rarely been applied in dermatology. The present study was an active attempt to formulate a stable phytocosmetic emulsion system loaded with 2% pre-concentrated Prosopis cineraria bark extract, aiming to revive facial skin properties. In order to obtain potent therapeutic activities, we first prepared extracts of stem, leaves, and bark and screen them on basis of phenolic, flavonoids contents and antioxidant, antibacterial, lipoxygenase and tyrosinase inhibition activities. Furthermore, cytocompatibility of the extract was also determined prior starting in vivo investigations. Then the in vivo performance of 2% bark extract loaded emulsion formulation was determined by using non-invasive probe cutometer and elastometer with comparison to base formulation. The preliminary experiment showed that bark extract has a significant amount of phenolic and flavonoid compounds with eminent antioxidant potential. Furthermore, indicated an efficient antibacterial, lipoxygenase, and tyrosinase enzyme inhibition activities. Importantly, the bark extract did not induce any toxicity or apoptosis, when incubated with HaCat cells. Moreover, the in vivo results showed the formulation (size 3 μm) decreased the skin melanin, erythema and sebum contents up to 2.1-,2.7-and 79%, while increased the skin hydration and elasticity up to 2-folds and 22% as compared to the base, respectively. Owing to enhanced therapeutic effects the phytocosmetic formulation proved to be a potential skin whitening, moisturizer, anti-acne, anti-wrinkle, anti-aging therapy and could actively induce skin rejuvenation and resurfacing.

Amorphous Nanosuspensions Aggregated from Paclitaxel⁻Hemoglobulin Complexes with Enhanced Cytotoxicity

Amorphous nanosuspensions (ANSs) enable rapid release and improved delivery of a poorly water-soluble drug; however, their preparation is challenging. Here, using hemoglobin (Hb) as a carrier, ANSs aggregated from paclitaxel (PTX)⁻Hb complexes were prepared to improve delivery of the hydrophobic anti-cancer agent. An affinity study demonstrated strong interaction between Hb and PTX. Importantly, the complexes could aggregate into <300 nm ANSs with high drug loading, which acidic condition facilitated their formation. Furthermore, the ANSs possessed improved cytotoxicity against cancer cells over the crystalline nanosuspensions. Taken together, ANSs aggregated from PTX⁻Hb complexes were developed, which could kill cancer cells with high efficiency.

A drug-delivering-drug strategy for combined treatment of metastatic breast cancer

Treatment of metastatic cancer continues to be a huge challenge worldwide. Notably, drug nanocrystals (Ns) in nanosuspensions clearly belong to a type of nanoparticle. Therefore, a question arose as to whether these drug particles can also be applied as carriers for drug delivery. Here, we design a novel paclitaxel (PTX) nanocrystal stabilized with complexes of matrix metalloproteinase (MMP)-sensitive β-casein/marimastat (MATT) for co-delivering MATT and PTX and combined therapy of metastatic breast cancer. The prepared Ns (200 nm) with a drug-loading of >50% were potent in treatment of metastatic cancer, which markedly inhibited MMP expression and activity and greatly blocked the lung metastasis and angiogenesis. In conclusion, employing protein-drug complexes as stabilizers, Ns with dual payloads are developed and are a promising strategy for co-delivery. Furthermore, the developed Ns can target the tumor microenvironment and cancer cells and, as a result, enable efficient treatment for breast metastatic cancer.

Pharmaceutical Dispersion Techniques for Dissolution and Bioavailability Enhancement of Poorly Water-Soluble Drugs

Over the past decades, a large number of drugs as well as drug candidates with poor dissolution characteristics have been witnessed, which invokes great interest in enabling formulation of these active ingredients. Poorly water-soluble drugs, especially biopharmaceutical classification system (BCS) II ones, are preferably designed as oral dosage forms if the dissolution limit can be broken through. Minimizing a drug’s size is an effective means to increase its dissolution and hence the bioavailability, which can be achieved by specialized dispersion techniques. This article reviews the most commonly used dispersion techniques for pharmaceutical processing that can practically enhance the dissolution and bioavailability of poorly water-soluble drugs. Major interests focus on solid dispersion, lipid-based dispersion (nanoencapsulation), and liquisolid dispersion (drug solubilized in a non-volatile solvent and dispersed in suitable solid excipients for tableting or capsulizing), covering the formulation development, preparative technique and potential applications for oral drug delivery. Otherwise, some other techniques that can increase the dispersibility of a drug such as co-precipitation, concomitant crystallization and inclusion complexation are also discussed. Various dispersion techniques provide a productive platform for addressing the formulation challenge of poorly water-soluble drugs. Solid dispersion and liquisolid dispersion are most likely to be successful in developing oral dosage forms. Lipid-based dispersion represents a promising approach to surmounting the bioavailability of low-permeable drugs, though the technique needs to traverse the obstacle from liquid to solid transformation. Novel dispersion techniques are highly encouraged to develop for formulation of poorly water-soluble drugs.

Drug-delivering-drug platform-mediated potent protein therapeutics via a non-endo-lysosomal route

Protein therapeutics is playing an increasingly critical role in treatment of human diseases. However, current vectors are captured by the digestive endo-lysosomal system, which results in an extremely low fraction (<2%) of protein being released in the cytoplasm. This paper reports a drug-delivering-drug platform (HA-PNPplex, 200 nm) for potent intracellular delivery of protein and combined treatment of cancer.

Methods: The platform was prepared by loading functional protein on pure drug nanoparticles (PNPs) followed by hyaluronic acid coating and was characterized by dynamic light scattering, transmission electron microscopy, and gel electrophoresis. In vitro, cellular uptake, trafficking, and cytotoxicity were evaluated by flow cytometry and confocal laser microscopy. Protein expression was assayed by western blot. In vivo, blood circulation and biodistribution were studied using a fluorescence imaging system, antitumor efficacy was assessed in a caspase 3-deficient tumor model, and biocompatibility was determined by comparison of hemolytic activity and proinflammatory cytokines and tissue histology.

Results: HA-PNPplex delivered the functional protein, caspase 3, to cells via bypassing endo-lysosomes and raised the caspase-3 level 6.5-fold in caspase 3-deficient cells. Promoted tumor accumulation (1.5-fold) and penetration were exhibited, demonstrating a high tumor-targeting ability of HA-PNPplex. HA-PNPplex rendered a 7-fold increase in caspase 3 in tumor and allowed for a 100% tumor growth inhibition and >60% apoptosis, implying significant antitumor activities.

Conclusions: This platform gains cellular entry without entrapment in the endo-lysosomes and enables efficient intracellular protein delivery and resultant profound cancer treatment. This platform, with extremely high drug-loading, is a valuable platform for combined cancer therapy with small-molecule drugs and proteins. More importantly, this work offers a robust and safe approach for protein therapeutics and intracellular delivery of other functional peptides, as well as gene-based therapy.

Phloroglucinol Derivatives from the Fruits of Eucalyptus globulus and Their Cytotoxic Activities

A new phloroglucinol derivative, named eucalyptin B (1), along with five related known compounds (2 - 6), was isolated from the fruits of Eucalyptus globulus. Their structures were elucidated by means of 1D- and 2D-NMR spectroscopy, with the absolute configuration of 1 determined by electronic circular dichroism (ECD) calculations. All isolated compounds (1 - 6) were evaluated for their cytotoxic activities against lung (A549), breast (4T1), and skin (B16F10) cancer cell lines. On the basis of cell viability assay, the cytotoxic activity of eucalyptin B (1) was further confirmed by apoptosis assay. Additionally, after treatment with eucalyptin B (1), the apoptosis factor proteins (Bcl2 and Bax) and caspase-3 levels in A549 cells were also determined by Western-blot analysis. By cytotoxic assay, eucalyptin B (1) exhibited potent cytotoxicity against A549 cells with an IC₅₀ value of 1.51 μm and induced concentration dependent apoptosis of up to 49%. Additionally, eucalyptin B (1) inhibited 5-fold and increased 10-folds in the level of Bcl2 and Bax, respectively. Furthermore, the 11-fold increase in the level of caspase-3 confirmed eucalyptin B (1) activated caspase dependent apoptosis pathway. In conclusion, the isolated compound eucalyptin B (1) has promising cytotoxic activity in tumor cells, especially in A549.