Pharmacological and toxicological assessment of innovative self-assembled polymeric micelles as powders for insulin pulmonary delivery

Pharmacological impact of microRNAs in head and neck squamous cell carcinoma: Prevailing insights on molecular pathways, diagnosis, and nanomedicine treatment

Head and neck squamous cell carcinoma is a disease that most commonly produce tumours from the lining of the epithelial cells of the lips, larynx, nasopharynx, mouth, or oro-pharynx. It is one of the most deadly forms of cancer. About one to two percent of all neo-plasm-related deaths are attributed to head and neck squamous cell carcinoma, which is responsible for about six percent of all cancers. MicroRNAs play a critical role in cell proliferation, differentiation, tumorigenesis, stress response, triggering apoptosis, and other physiological process. MicroRNAs regulate gene expression and provide new diagnostic, prognostic, and therapeutic options for head and neck squamous cell carcinoma. In this work, the role of molecular signaling pathways related to head and neck squamous cell carcinoma is emphasized. We also provide an overview of MicroRNA downregulation and overexpression and its role as a diagnostic and prognostic marker in head and neck squamous cell carcinoma. In recent years, MicroRNA nano-based therapies for head and neck squamous cell carcinoma have been explored. In addition, nanotechnology-based alternatives have been discussed as a promising strategy in exploring therapeutic paradigms aimed at improving the efficacy of conventional cytotoxic chemotherapeutic agents against head and neck squamous cell carcinoma and attenuating their cytotoxicity. This article also provides information on ongoing and recently completed clinical trials for therapies based on nanotechnology.

Nano-delivery to the lung - by inhalation or other routes and why nano when micro is largely sufficient?

Respiratory diseases gather a wide range of disorders which are generally difficult to treat, partly due to a poor delivery of drugs to the lung with adequate dose and minimum side effects. With the recent developments of nanotechnology, nano-delivery systems have raised interest. In this review, we detail the main types of nanocarriers that have been developed presenting their respective advantages and limitations. We also discuss the route of administration (systemic versus by inhalation), also considering technical aspects (different types of aerosol devices) with concrete examples of applications. Finally, we propose some perspectives of development in the field such as the nano-in-micro approaches, the emergence of drug vaping to generate airborne carriers in the submicron size range, the development of innovative respiratory models to assess regional aerosol deposition of nanoparticles or the application of nano-delivery to the lung in the treatment of other diseases.

Expanding the arsenal against pulmonary diseases using surface-functionalized polymeric micelles: breakthroughs and bottlenecks

Pulmonary diseases such as lung cancer, asthma and tuberculosis have remained one of the common challenges globally. Polymeric micelles (PMs) have emerged as an effective technique for achieving targeted drug delivery for a local as well as a systemic effect. These PMs encapsulate and protect hydrophobic drugs, increase pulmonary targeting, decrease side effects and enhance drug efficacy through the inhalation route. In the current review, emphasis has been placed on the different barriers encountered by the drugs given via the pulmonary route and the mechanism of PMs in achieving drug targeting. The applications of PMs in different pulmonary diseases have also been discussed in detail.

Insights into Nanomedicine for Head and Neck Cancer Diagnosis and Treatment

Head and neck cancers rank sixth among the most common cancers today, and the survival rate has remained virtually unchanged over the past 25 years, due to late diagnosis and ineffective treatments. They have two main risk factors, tobacco and alcohol, and human papillomavirus infection is a secondary risk factor. These cancers affect areas of the body that are fundamental for the five senses. Therefore, it is necessary to treat them effectively and non-invasively as early as possible, in order to do not compromise vital functions, which is not always possible with conventional treatments (chemotherapy or radiotherapy). In this sense, nanomedicine plays a key role in the treatment and diagnosis of head and neck cancers. Nanomedicine involves using nanocarriers to deliver drugs to sites of action and reducing the necessary doses and possible side effects. The main purpose of this review is to give an overview of the applications of nanocarrier systems to the diagnosis and treatment of head and neck cancer. Herein, several types of delivery strategies, radiation enhancement, inside-out hyperthermia, and theragnostic approaches are addressed.

Colorectal cancer inhibition by BET inhibitor JQ1 is MYC-independent and not improved by nanoencapsulation

Bromodomain and extraterminal domain protein inhibitors (BETi) for cancer treatment did not convince during their first clinical trials. Their epigenetic mechanism of action is still not well understood, even if MYC is generally considered as its main downstream target. In this context, we intended to assess two new nanoformulations of the BETi JQ1 for the treatment of colorectal cancer (CRC). JQ1 was encapsulated at 10 mg/mL in lipid nanocapsules (LNC) or polymeric micelles (PM), both compatible for an intravenous administration. Their effect was compared with free JQ1 on several CRC cell lines in vitro and with daily intraperitoneal cyclodextrin (CD)-loaded JQ1 on the CT26 CRC tumor model in vivo. We showed that LNC preferentially accumulated in tumor, liver, and lymph nodes. LNC-JQ1 and CD-JQ1 similarly delayed tumor growth and increased median survival from 15 to 23 or 20.5 days. JQ1 altered MYC in only two among four CRC cell lines. This MYC-independence found in CT26 was confirmed in vivo by PCR and immunohistochemistry. The main explanation of the JQ1 anticancer effect was an increase in apoptosis. The investigation of its impact on the tumor microenvironment did not show significant effects. Finally, JQ1 association with irinotecan did not synergize in vivo with JQ1 nanoformulations. In conclusion, we demonstrated that the JQ1 anticancer effect was not improved by nanoencapsulation even if their tumor delivery was probably higher. MYC inhibition was not associated to JQ1 efficacy in the case of the CT26 CRC murine model.

Reactive oxygen species-sensitive polymeric nanocarriers for synergistic cancer therapy

Reactive oxygen species (ROS)-responsive nanocarriers have aroused widespread interest in recent years. On the one hand, a high ROS level has been detected in many types of tumor cells. On the other hand, ROS generation is also induced during photodynamic, sonodynamic, or chemodynamic therapy. In addition, multiple types of polymers are sensitive to ROS. Therefore, numerous ROS-responsive polymeric nanocarriers with unique ROS-responsive characteristics have been developed. This review discusses ROS-sensitive polymeric nanocarriers to improve drug delivery efficacy. In particular, ROS-responsive nanocarriers for synergistic cancer therapy are highlighted. The development of novel ROS-sensitive nanocarriers holds great potential for combining ROS-mediated therapy, such as photodynamic therapy, and other therapies to achieve synergistic anticancer efficacy. STATEMENT OF SIGNIFICANCE: Reactive oxygen species (ROS)-responsive nanocarriers aroused widespread interest in recent years. On the one hand, a high level of ROS has been found in many types of tumor cells. On the other hand, the ROS generation can also be induced during the photodynamic, sonodynamic, or chemodynamic therapy. Besides, multiple types of polymers were sensitive to the ROS. Therefore, numerous ROS-responsive polymeric nanocarriers with unique ROS responsive characteristics have been developed. This review focuses on the ROS-sensitive polymeric nanocarriers to improve drug delivery efficacy for synergistic cancer therapy.

Pluronic F127 micelles improve the stability and enhance the anticancer stem cell efficacy of citral in breast cancer

Aim: Improving the stability and anti-cancer stem cell (CSC) activity of citral, a natural ALDH1A inhibitor. Materials & methods: Citral-loaded micelles (CLM) were obtained using Pluronic^® F127 and its efficacy tested on the growth of four breast cancer cell lines. The impact of the CLM on the growth and functional hallmarks of breast CSCs were also evaluated using mammosphere and CSC reporter cell lines. Results: CLM improved the stability and growth inhibitory effects of citral. Importantly, CLM fully blocking the stemness features of CSCs (self-renewal, differentiation and migration) and in combination with paclitaxel CLM sensitized breast cancer cells to the chemotherapy. Conclusion: Targeting CSCs with CLM could improve the treatment of advanced breast cancer in combination with the standard chemotherapy.

Cyclic Dipeptide: A Privileged Molecular Scaffold to Derive Structural Diversity and Functional Utility

Cyclic dipeptides (CDPs) are the simplest form of cyclic peptides with a wide range of applications from therapeutics to biomaterials. CDP is a versatile molecular platform endowed with unique properties such as conformational rigidity, intermolecular interactions, structural diversification through chemical synthesis, bioavailability and biocompatibility. A variety of natural products with the CDP core exhibit anticancer, antifungal, antibacterial, and antiviral activities. The inherent bioactivities have inspired the development of synthetic analogues as drug candidates and drug delivery systems. CDP plays a crucial role as conformation and molecular assembly directing core in the design of molecular receptors, peptidomimetics and fabrication of functional material architectures. In recent years, CDP has rapidly become a privileged scaffold for the design of advanced drug candidates, drug delivery agents, bioimaging, and biomaterials to mitigate numerous disease conditions. This review describes the structural diversification and multifarious biomedical applications of the CDP scaffold, discusses challenges, and provides future directions for the emerging field.

Dry powder pharmaceutical biologics for inhalation therapy

Therapeutic biologics such as genes, peptides, proteins, virus and cells provide clinical benefits and are becoming increasingly important tools in respiratory medicine. Pulmonary delivery of therapeutic biologics enables the potential for safe and effective treatment option for respiratory diseases due to high bioavailability while minimizing absorption into the systemic circulation, reducing off-target toxicity to other organs. Development of inhalable powder formulation requires stabilization of complex biological materials, and each type of biologics may present unique challenges and require different formulation strategy combined with manufacture process to ensure biological and physical stabilities during production and over shelf-life. This review examines key formulation strategies for stabilizing proteins, nucleic acids, virus (bacteriophages) and bacterial cells in inhalable powders. It also covers characterization methods used to assess physicochemical properties and aerosol performance of the powders, biological activity and structural integrity of the biologics, and chemical analysis at the nanoscale. Furthermore, the review includes manufacture technologies which are based on lyophilization and spray-drying as they have been applied to manufacture Food and Drug Administration (FDA)-approved protein powders. In perspective, formulation and manufacture of inhalable powders for biologic are highly challenging but attainable. The key requirements are the stability of both the biologics and the powder, along with the powder dispersibility. The formulation to be developed depends on the manufacture process as it will subject the biologics to different stresses (temperature, mechanical and chemical) which could lead to degradation by different pathways. Stabilizing excipients coupled with the suitable choice of process can alleviate the stability issues of inhaled powders of biologics.

Progress in the Application of Nano- and Micro-based Drug Delivery Systems in Pulmonary Drug Delivery

Nanotechnology is associated with the development of particles in the nano-size range that can be used in a wide range of applications in the medical field. It has gained more importance in the pharmaceutical research field particularly in drug delivery, as it results in enhanced therapeutic drug performance, improved drug solubility, targeted drug delivery to the specific sites, minimized side effects, and prolonged drug retention time in the targeted site. To date, the application of nanotechnology continues to offer several benefits in the treatment of various chronic diseases and results in remarkable improvements in treatment outcomes. The use of nano-based delivery systems such as liposomes, micelles, and nanoparticles in pulmonary drug delivery have shown to be a promising strategy in achieving drug deposition and maintained controlled drug release in the lungs. They have been widely used to minimize the risks of drug toxicity in vivo. In this review, recent advances in the application of nano- and micro-based delivery systems in pulmonary drug delivery for the treatment of various pulmonary diseases, such as lung cancer, asthma, and chronic obstructive pulmonary disease, are highlighted. Limitations in the application of these drug delivery systems and some key strategies in improving their formulation properties to overcome challenges encountered in drug delivery are also discussed.

Excipient-free pulmonary insulin dry powder: Pharmacokinetic and pharmacodynamics profiles in rats

A novel pure insulin spray-dried powder for DPI product (Ins_SD) was studied with respect to physico-chemical stability, in vitro respirability, bioavailability, activity and tolerability. Ins_SD powder exhibited a very high in vitro respirability, independently of the DPI product preparation (manual or semi-automatic). Physico-chemical characteristics of Ins_SD powder remained within the pharmacopoeia limits during 6 months of storage at room temperature. PK/PD profiles were measured in rats that received the pulmonary powders by intratracheal insufflation and compared with Afrezza inhalation insulin. Due to the low drug powder mass to deliver, both insulin powders were diluted with mannitol. Insulin from Ins_SD was promptly absorbed (t_max 15 min and C_maxx4.9 ± 1.5 mU/ml). Afrezza had a slower absorption (t_max 30 min and C_max of 1.8 ± 0.37 mU/ml). After glucose injection, Ins_SD determined a rapid reduction of glucose level, similar to Afrezza. As reference, insulin subcutaneous injection showed a long-lasting hypoglycemic effect due to the slow absorption that prolonged insulin plasma level. In summary, Ins_SD product is suitable for post-prandial glucose control, providing a convenient and compliant product, in particular in the event of using a disposable device. Albeit the product has to be stored in fridge, its stability at room temperature allows the diabetic individual to carry the daily dose in normal conditions.

Intracellular Delivery of Anti-SMC2 Antibodies against Cancer Stem Cells

Structural maintenance of chromosomes protein 2 (SMC2) is a central component of the condensin complex involved in DNA supercoiling, an essential process for embryonic stem cell survival. SMC2 over-expression has been related with tumorigenesis and cancer malignancy and its inhibition is regarded as a potential therapeutic strategy even though no drugs are currently available. Here, we propose to inhibit SMC2 by intracellular delivery of specific antibodies against the SMC2 protein. This strategy aims to reduce cancer malignancy by targeting cancer stem cells (CSC), the tumoral subpopulation responsible of tumor recurrence and metastasis. In order to prevent degradation and improve cellular internalization, anti-SMC2 antibodies (Ab-SMC2) were delivered by polymeric micelles (PM) based on Pluronic^® F127 amphiphilic polymers. Importantly, scaffolding the Ab-SMC2 onto nanoparticles allowed its cellular internalization and highly increased its efficacy in terms of cytotoxicity and inhibition of tumorsphere formation in MDA-MB-231 and HCT116 breast and colon cancer cell lines, respectively. Moreover, in the case of the HCT116 cell line G1, cell-cycle arrest was also observed. In contrast, no effects from free Ab-SMC2 were detected in any case. Further, combination therapy of anti-SMC2 micelles with paclitaxel (PTX) and 5-Fluorouracil (5-FU) was also explored. For this, PTX and 5-FU were respectively loaded into an anti-SMC2 decorated PM. The efficacy of both encapsulated drugs was higher than their free forms in both the HCT116 and MDA-MB-231 cell lines. Remarkably, micelles loaded with Ab-SMC2 and PTX showed the highest efficacy in terms of inhibition of tumorsphere formation in HCT116 cells. Accordingly, our data clearly suggest an effective intracellular release of antibodies targeting SMC2 in these cell models and, further, strong cytotoxicity against CSC, alone and in combined treatments with Standard-of-Care drugs.

Zileuton™ loaded in polymer micelles effectively reduce breast cancer circulating tumor cells and intratumoral cancer stem cells

Tumor recurrence, metastatic spread and progressive gain of chemo-resistance of advanced cancers are sustained by the presence of cancer stem cells (CSCs) within the tumor. Targeted therapies with the aim to eradicate these cells are thus highly regarded. However, often the use of new anti-cancer therapies is hampered by pharmacokinetic demands. Drug delivery through nanoparticles has great potential to increase efficacy and reduce toxicity and adverse effects. However, its production has to be based on intelligent design. Likewise, we developed polymeric nanoparticles loaded with Zileuton™, a potent inhibitor of cancer stem cells (CSCs), which was chosen based on high throughput screening. Its great potential for CSCs treatment was subsequently demonstrated in in vitro and in in vivo CSC fluorescent models. Encapsulated Zileuton™ reduces amount of CSCs within the tumor and effectively blocks the circulating tumor cells (CTCs) in the blood stream and metastatic spread.

Nanotechnology Advanced Strategies for the Management of Diabetes Mellitus

Background:

Medications currently available for the management of diabetes mellitus are inconvenient and have some limitations. Thus, investigations for novel approaches are needed to deliver and target antidiabetics safely to the site of action.

Objective:

The present review emphasizes the limitations of conventional antidiabetics and provides the recent progresses of nanotechnology in the treatment of diabetes mellitus with a special highlight on the novel nanocarriers methodologies employed as antidiabetic drug delivery systems.

Methods:

The potential nanocarriers employed for the treatment of diabetes comprise liposomes, niosomes, self-nanoemulsifying drug delivery systems, polymeric nanoparticles, gold nanoparticles, dendrimers and micelles. Herbal nanomedicine has also emerged to be a promising way for adequate delivery of herbal compounds. Other nanotechnology approaches involve the usage of oral insulin, inhalable insulin, artificial pancreas, and nanopump.

Results:

Nanocarriers have proved to lead a successful delivery of antidiabetic medications, aiming at drug targeting for enhanced efficacy and safety.

Conclusion:

These innovative generations of drug delivery systems have important benefits over conventionally existing ones. The future of nanotechnology in the management of diabetes is still open with several prospects and will be of pronounced significance.

Pulmonary delivery by exploiting doxorubicin and cisplatin co-loaded nanoparticles for metastatic lung cancer therapy

Despite advances in cancer therapy, effective local treatment remains a formidable challenge due to the limit of efficient drug delivery method and the toxicity of chemotherapeutics. In the current study, a combined system was developed for simultaneous delivering doxorubicin (DOX) and cis-platinum (CDDP) to the lungs via pulmonary administration. Methoxy poly(ethylene glycol)-poly(ethylenimine)-poly(l-glutamate) (mPEG-OEI-PLG) copolymers were synthesized as a carrier for the co-delivery of DOX and CDDP. The co-delivery nanoparticles (Co-NPs) were formed with mPEG-OEI-PLG via electrostatic interactions for DOX loading and chelate interactions for CDDP loading, respectively. The results of in vitro cytotoxicity assays against B16F10 cell line showed that Co-NPs exhibited higher cytotoxicity than those treated with either DOX or CDDP alone. In the B16F10 tumor-bearing mice models, local delivery of Co-NPs by pulmonary administration demonstrated that Co-NPs had highly efficient accumulation in the lungs, especially in the tumor tissues of the lungs, but rarely in normal lung tissues. Moreover, Co-NPs exhibited higher anti-tumor efficiency for metastatic lung cancer than that in the single treatment of DOX or CDDP, while no obvious side effects were observed during the pulmonary treatment. The present pulmonary delivery by exploiting co-loaded nanoparticles was proved to be a promising drug delivery strategy for effective lung cancer therapy.

Efficacy of Meglumine Antimoniate in a Low Polymerization State Orally Administered in a Murine Model of Visceral Leishmaniasis

Progress toward the improvement of meglumine antimoniate (MA), commercially known as Glucantime, a highly effective but also toxic antileishmanial drug, has been hindered by the lack of knowledge and control of its chemical composition. Here, MA was manipulated chemically with the aim of achieving an orally effective drug. MA compounds were synthesized from either antimony pentachloride (MA-SbCl₅) or potassium hexahydroxyantimonate [MA-KSb(OH)₆] and prepared under a low polymerization state. These compounds were compared to Glucantime regarding chemical composition, permeation properties across a cellulose membrane and Caco-2 cell monolayer, and uptake by peritoneal macrophages. MA-SbCl₅ and MA-KSb(OH)₆ were characterized as less polymerized and more permeative 2:2 Sb-meglumine complexes than Glucantime, which consisted of a mixture of 2:3 and 3:3 Sb-meglumine complexes. The antileishmanial activities and hepatic uptake of all compounds were evaluated after oral administration in BALB/c mice infected with Leishmania infantum chagasi, as a model of visceral leishmaniasis (VL). The synthetic MA compounds given at 300 mg Sb/kg of body weight/12 h for 30 days significantly reduced spleen and liver parasite burdens, in contrast to those for Glucantime at the same dose. The greater activity of synthetic compounds could be attributed to their higher intestinal absorption and accumulation efficiency in the liver. MA-SbCl₅ given orally was as efficacious as Glucantime by the parenteral route (80 mg Sb/kg/24 h intraperitoneally). These data taken together suggest that treatment with a less-polymerized form of MA by the oral route may be effective for the treatment of VL.

In vitro/in vivo investigation on the potential of Pluronic® mixed micelles for pulmonary drug delivery

In this paper, we shed light on the potential of Pluronic® mixed micelles in lung delivery of poorly water-soluble drugs. To this purpose, Pluronic® P123/F127 mixed micelles (PMM), exhibiting superior stability in biological fluids, were loaded with budesonide (BUD), a model hydrophobic corticosteroid, and fully investigated focusing on their stability in pulmonary-relevant media, transport through the mucus barrier and aerodynamic behaviour in vitro. Then, lung bio-distribution and efficacy were evaluated in vivo, after intra-tracheal administration in rats. PMM showed excellent stability in saline, mucin, artificial airway mucus and simulated interstitial lung fluid. Likely due to their small size coupled with the hydrophilic biofouling shell, PMM did not interact with mucin and consequently diffused through artificial mucus. BUD was loaded with high efficiency in PMM and released at sustained rate in artificial mucus. BUD-PMM dispersion in saline was efficiently delivered through a common jet nebulizer without aggregation. After intratracheal administration in rats, PMM labelled with Rhodamine B persisted in the lung up to 24 h, while serum levels rapidly dropped. Finally, the effects of BUD-PMM in a rat model of lung inflammation induced by intra-tracheal aerosolization of lipopolysaccharide (LPS) from E. coli were investigated. Of note, a single intra-tracheal aerosolization of BUD-PMM significantly reduced bronchoalveolar neutrophil infiltration and the expression of protein/enzymes derived from the arachidonic acid cascade induced by LPS, whereas a control BUD aqueous suspension showed a weaker effect. Overall, this study demonstrates that inhalable formulations of PMM can be considered as a platform for local delivery of hydrophobic drugs at lungs worth of further consideration.

Polymeric mixed micelles as nanomedicines: Achievements and perspectives

During the past few decades, polymeric micelles have raised special attention as novel nano-sized drug delivery systems for optimizing the treatment and diagnosis of numerous diseases. These nanocarriers exhibit several in vitro and in vivo advantages as well as increased stability and solubility to hydrophobic drugs. An interesting approach for optimizing these properties and overcoming some of their disadvantages is the combination of two or more polymers in order to assemble polymeric mixed micelles. This review article gives an overview on the current state of the art of several mixed micellar formulations as nanocarriers for drugs and imaging probes, evaluating their ongoing status (preclinical or clinical stage), with special emphasis on type of copolymers, physicochemical properties, in vivo progress achieved so far and toxicity profiles. Besides, the present article presents relevant research outcomes about polymeric mixed micelles as better drug delivery systems, when compared to polymeric pristine micelles. The reported data clearly illustrates the promise of these nanovehicles reaching clinical stages in the near future.