Salinomycin-loaded Nanofibers for Glioblastoma Therapy

Co-loading of Temozolomide with Oleuropein or rutin into polylactic acid core-shell nanofiber webs inhibit glioblastoma cell by controlled release

Glioblastoma (GB) has susceptibility to post-surgical recurrence. Therefore, local treatment methods are required against recurrent GB cells in the post-surgical area. In this study, we developed a nanofiber-based local therapy against GB cells using Oleuropein (OL), and rutin and their combinations with Temozolomide (TMZ). The polylactic acid (PLA) core-shell nanofiber webs were encapsulated with OL (PLAOL), rutin (PLArutin), and TMZ (PLATMZ) by an electrospinning process. A SEM visualized the morphology and the total immersion method determined the release characteristics of PLA webs. Real-time cell tracking analysis for cell growth, dual Acridine Orange/Propidium Iodide staining for cell viability, a scratch wound healing assay for migration capacity, and a sphere formation assay for tumor spheroid aggressiveness were used. All polymeric nanofiber webs had core-shell structures with an average diameter between 133 ± 30.7-139 ± 20.5 nm. All PLA webs promoted apoptotic cell death, suppressed cell migration, and spheres growth (p < 0.0001). PLAOL and PLATMZ suppressed GB cell viability with a controlled release that increased over 120 h, while PLArutin caused rapid cell inhibition (p < 0.0001). Collectively, our findings suggest that core-shell nano-webs could be a novel and effective therapeutic tool for the controlled release of OL and TMZ against recurrent GB cells.

The Golgi Apparatus as an Anticancer Therapeutic Target

Although the discovery of the Golgi apparatus (GA) was made over 125 years ago, only a very limited number of therapeutic approaches have been developed to target this complex organelle. The GA serves as a modification and transport center for proteins and lipids and also has more recently emerged as an important store for some ions. The dysregulation of GA functions is implicated in many cellular processes associated with cancer and some GA proteins are indeed described as cancer biomarkers. This dysregulation can affect protein modification, localization, and secretion, but also cellular metabolism, redox status, extracellular pH, and the extracellular matrix structure. Consequently, it can directly or indirectly affect cancer progression. For these reasons, the GA is an appealing anticancer pharmacological target. Despite this, no anticancer drug specifically targeting the GA has reached the clinic and few have entered the clinical trial stage. Advances in nanodelivery approaches may help change this scenario by specifically targeting tumor cells and/or the GA through passive, active, or physical strategies. This article aims to examine the currently available anticancer GA-targeted drugs and the nanodelivery strategies explored for their administration. The potential benefits and challenges of modulating and specifically targeting the GA function in the context of cancer therapy are discussed.

A facile, flexible, and multifunctional thermo-chemotherapy system for customized treatment of drug-resistant breast cancer

Anticancer drug resistance invariably emerges and poses a significant barrier to curative therapy for various breast cancers. This results in a lack of satisfactory therapeutic medicine for cancer treatment. Herein, a universal vector system for drug-resistance breast cancer was designed to meet the needs of reversed multidrug resistance, thermo-chemotherapy, and long-term drug release behavior. The vector system comprises polycaprolactone (PCL) nanofiber mesh and magnetic nanoparticles (MNPs). PCL has excellent biocompatibility and electrospinning performance. In this study, MNPs were tailored to be thermogenic in response to an alternating magnetic field (AMF). PCL nanofiber can deliver various chemotherapy drugs, and suitable MNPs encapsulated in the nanofiber can generate hyperthermia and synergistic effect with those chemotherapy drugs. Therefore, a more personalized treatment system can be developed for different breast malignancies. In addition, the PCL nanofiber mesh (NFM) enables sustained release of the drugs for up two months, avoiding the burden on patients caused by repeated administration. Through model drugs doxorubicin (DOX) and chemosensitizers curcumin (CUR), we systematically verified the therapeutic effect of DOX-resistance breast cancer and inhibition of tumor generation in vivo. These findings represent a multifaceted platform of importance for validating strategic reversed MDR in pursuit of promoted thermo-chemotherapeutic outcomes. More importantly, the low cost and excellent safety and efficacy of this nanofiber mesh demonstrate that this can be customized multi-function vector system may be a promising candidate for refractory cancer therapy in clinical.

Electrospun Drug-Loaded and Gene-Loaded Nanofibres: The Holy Grail of Glioblastoma Therapy?

To date, GBM remains highly resistant to therapies that have shown promising effects in other cancers. Therefore, the goal is to take down the shield that these tumours are using to protect themselves and proliferate unchecked, regardless of the advent of diverse therapies. To overcome the limitations of conventional therapy, the use of electrospun nanofibres encapsulated with either a drug or gene has been extensively researched. The aim of this intelligent biomaterial is to achieve a timely release of encapsulated therapy to exert the maximal therapeutic effect simultaneously eliminating dose-limiting toxicities and activating the innate immune response to prevent tumour recurrence. This review article is focused on the developing field of electrospinning and aims to describe the different types of electrospinning techniques in biomedical applications. Each technique describes how not all drugs or genes can be electrospun with any method; their physico-chemical properties, site of action, polymer characteristics and the desired drug or gene release rate determine the strategy used. Finally, we discuss the challenges and future perspectives associated with GBM therapy.

Nanotechnology-based approaches overcome lung cancer drug resistance through diagnosis and treatment

Lung cancer continues to be a malignant tumor with high mortality. Two obstacles interfere with curative therapy of lung cancer: (i) poor diagnosis at the early stages, as symptoms are not specific or asymptomatic; and (ii) invariably emerging drug resistance after treatment. Some factors contributing to drug resistance include preexisting genetic/genomic drug-resistant alteration(s); activation of adaptive drug resistance pathways; remodeling of the tumor microenvironment; and pharmacological mechanisms or activation of drug efflux pumps. Despite the mechanisms explored to better understand drug resistance, a gap remains between molecular understanding and clinical application. Therefore, facilitating the translation of basic science into the clinical setting is a great challenge. Nanomedicine has emerged as a promising tool for cancer treatment. Because of their excellent physicochemical properties and enhanced permeability and retention effects, nanoparticles have great potential to revolutionize conventional lung cancer diagnosis and combat drug resistance. Nanoplatforms can be designed as carriers to improve treatment efficacy and deliver multiple drugs in one system, facilitating combination treatment to overcome drug resistance. In this review, we describe the difficulties in lung cancer treatment and review recent research progress on nanoplatforms aimed at early diagnosis and lung cancer treatment. Finally, future perspectives and challenges of nanomedicine are also discussed.

Fabrication and Modelling of a Reservoir-Based Drug Delivery System for Customizable Release

Localized therapy approaches have emerged as an alternative drug administration route to overcome the limitations of systemic therapies, such as the crossing of the blood–brain barrier in the case of brain tumor treatment. For this, implantable drug delivery systems (DDS) have been developed and extensively researched. However, to achieve an effective localized treatment, the release kinetics of DDS needs to be controlled in a defined manner, so that the concentration at the tumor site is within the therapeutic window. Thus, a DDS, with patient-specific release kinetics, is crucial for the improvement of therapy. Here, we present a computationally supported reservoir-based DDS (rDDS) development towards patient-specific release kinetics. The rDDS consists of a reservoir surrounded by a polydimethylsiloxane (PDMS) microchannel membrane. By tailoring the rDDS, in terms of membrane porosity, geometry, and drug concentration, the release profiles can be precisely adapted, with respect to the maximum concentration, release rate, and release time. The release is investigated using a model dye for varying parameters, leading to different distinct release profiles, with a maximum release of up to 60 days. Finally, a computational simulation, considering exemplary in vivo conditions (e.g., exchange of cerebrospinal fluid), is used to study the resulting drug release profiles, demonstrating the customizability of the system. The establishment of a computationally supported workflow, for development towards a patient-specific rDDS, in combination with the transfer to suitable drugs, could significantly improve the efficacy of localized therapy approaches.

Pharmaceutical Aspects of Nanocarriers for Smart Anticancer Therapy

Drug delivery to tumor sites using nanotechnology has been demonstrated to overcome the drawbacks of conventional anticancer drugs. Altering the surface shape and geometry of nanocomposites alters their chemical properties, which can confer multiple attributes to nanocarriers for the treatment of cancer and their use as imaging agents for cancer diagnosis. However, heterogeneity and blood flow in human cancer limit the distribution of nanoparticles at the site of tumor tisues. For targeted delivery and controlled release of drug molecules in harsh tumor microenvironments, smart nanocarriers combined with various stimuli-responsive materials have been developed. In this review, we describe nanomaterials for smart anticancer therapy as well as their pharmaceutical aspects including pharmaceutical process, formulation, controlled drug release, drug targetability, and pharmacokinetic or pharmacodynamic profiles of smart nanocarriers. Inorganic or organic-inorganic hybrid nanoplatforms and the electrospinning process have also been briefly described here.

Salinomycin-Based Drug Delivery Systems: Overcoming the Hurdles in Cancer Therapy

Cancer stem cells (CSCs) are reportedly responsible for the initiation and propagation of cancer. Since CSCs are highly resistant to conventional chemo- and radiotherapy, they are considered the main cause of cancer relapse and metastasis. Salinomycin (Sali), an anticoccidial polyether antibiotic, has emerged as a promising new candidate for cancer therapy, with selective cytotoxicity against CSCs in various malignancies. Nanotechnology provides an efficient means of delivering Sali to tumors in view of reducing collateral damage to healthy tissues and enhancing the therapeutic outcome. This review offers an insight into the most recent advances in cancer therapy using Sali-based nanocarriers.

Electrospun Nanofibrous Scaffolds: Review of Current Progress in the Properties and Manufacturing Process, and Possible Applications for COVID-19

Over the last twenty years, researchers have focused on the potential applications of electrospinning, especially its scalability and versatility. Specifically, electrospun nanofiber scaffolds are considered an emergent technology and a promising approach that can be applied to biosensing, drug delivery, soft and hard tissue repair and regeneration, and wound healing. Several parameters control the functional scaffolds, such as fiber geometrical characteristics and alignment, architecture, etc. As it is based on nanotechnology, the concept of this approach has shown a strong evolution in terms of the forms of the materials used (aerogels, microspheres, etc.), the incorporated microorganisms used to treat diseases (cells, proteins, nuclei acids, etc.), and the manufacturing process in relation to the control of adhesion, proliferation, and differentiation of the mimetic nanofibers. However, several difficulties are still considered as huge challenges for scientists to overcome in relation to scaffolds design and properties (hydrophilicity, biodegradability, and biocompatibility) but also in relation to transferring biological nanofibers products into practical industrial use by way of a highly efficient bio-solution. In this article, the authors review current progress in the materials and processes used by the electrospinning technique to develop novel fibrous scaffolds with suitable design and that more closely mimic structure. A specific interest will be given to the use of this approach as an emergent technology for the treatment of bacteria and viruses such as COVID-19.

A Smart Hyperthermia Nanofiber-Platform-Enabled Sustained Release of Doxorubicin and 17AAG for Synergistic Cancer Therapy

This study demonstrates the rational fabrication of a magnetic composite nanofiber mesh that can achieve mutual synergy of hyperthermia, chemotherapy, and thermo-molecularly targeted therapy for highly potent therapeutic effects. The nanofiber is composed of biodegradable poly(ε-caprolactone) with doxorubicin, magnetic nanoparticles, and 17-allylamino-17-demethoxygeldanamycin. The nanofiber exhibits distinct hyperthermia, owing to the presence of magnetic nanoparticles upon exposure of the mesh to an alternating magnetic field, which causes heat-induced cell killing as well as enhanced chemotherapeutic efficiency of doxorubicin. The effectiveness of hyperthermia is further enhanced through the inhibition of heat shock protein activity after hyperthermia by releasing the inhibitor 17-allylamino-17-demethoxygeldanamycin. These findings represent a smart nanofiber system for potent cancer therapy and may provide a new approach for the development of localized medication delivery.

Clinical applications of nanomedicines in lung cancer treatment

Lung cancer is the leading cause of cancer mortality worldwide. Owing to a lack of early-stage diagnosis, most lung cancers are detected in advanced stages, limiting the available therapeutic options. Moreover, extensive systemic chemotherapy of lung tumors is often associated with severe off-target toxicity and drug resistance of cancer cells, thus diminishing the outcomes of chemotherapy modalities. In this light, nanomedicines have opened an alternative avenue to develop more efficacious therapeutic platforms while addressing several current challenges. Clinical findings have revealed that nanomedicines improve the pharmacokinetics and biodistribution of the therapeutic agents while decreasing their systemic toxicity. This review provides an update on nanomedicines that have been clinically approved or are undergoing clinical trials for treatment of lung cancer. By discussing the clinical findings of the current nanoformulations, this review provides prospects for the development of more efficacious nanomedicines to improve the clinical outcomes of lung cancer treatment.

Salinomycin-loaded injectable thermosensitive hydrogels for glioblastoma therapy

Local drug delivery approaches for treating brain tumors not only diminish the toxicity of systemic chemotherapy, but also circumvent the blood-brain barrier (BBB) which restricts the passage of most chemotherapeutics to the brain. Recently, salinomycin has attracted much attention as a potential chemotherapeutic agent in a variety of cancers. In this study, poly (ethylene oxide)/poly (propylene oxide)/poly (ethylene oxide) (PEO-PPO-PEO, Pluronic F127) and poly (dl-lactide-co-glycolide-b-ethylene glycol-b-dl-lactide-co-glycolide) (PLGA-PEG-PLGA), the two most common thermosensitive copolymers, were utilized as local delivery systems for salinomycin in the treatment of glioblastoma. The Pluronic and PLGA-PEG-PLGA hydrogels released 100% and 36% of the encapsulated salinomycin over a one-week period, respectively. While both hydrogels were found to be effective at inhibiting glioblastoma cell proliferation, inducing apoptosis and generating intracellular reactive oxygen species, the Pluronic formulation showed better biocompatibility, a superior drug release profile and an ability to further enhance the cytotoxicity of salinomycin, compared to the PLGA-PEG-PLGA hydrogel formulation. Animal studies in subcutaneous U251 xenograftednudemice also revealed that Pluronic + salinomycin hydrogel reduced tumor growth compared to free salinomycin- and PBS-treated mice by 4-fold and 6-fold, respectively within 12 days. Therefore, it is envisaged that salinomycin-loaded Pluronic can be utilized as an injectable thermosensitive hydrogel platform for local treatment of glioblastoma, providing a sustained release of salinomycin at the tumor site and potentially bypassing the BBB for drug delivery to the brain.

Injectable biomaterials for treatment of glioblastoma

Despite ongoing advancements in the field of medicine, glioblastoma multiforme (GBM) is presently incurable, making this advanced brain tumor the deadliest tumor type in the central nervous system. The primary treatment strategies for GBM (i.e. surgical resection, radiation therapy, chemotherapy, and newly incorporated targeted therapies) fail to overcome the challenging characteristics of highly aggressive GBM tumors and are presently given with the goal of increasing the quality of life for patients. With the aim of creating effective treatment solutions, research has shifted toward utilizing injectable biomaterial adjuncts to minimize invasiveness of treatment, provide spatiotemporal control of therapeutic delivery, and engage with cells through material-cell interfaces. This review aims to summarize the limitations of the current standard of care for GBM, discuss how these limitations can be addressed by local employment of injectable biomaterial systems, and highlight developments in the field of biomaterials for these applications.

Salinomycin nanocrystals for colorectal cancer treatment through inhibition of Wnt/β-catenin signaling

Salinomycin (SAL) is one of the first discovered inhibitors of human cancer stem cells (CSCs), which acts via blocking the Wnt/β-catenin pathway. However, SAL has not been clinically used to treat human diseases due to its poor aqueous solubility and considerable toxicity. In this study, we developed salinomycin nanocrystals (SAL NCs) to treat colorectal cancer through the inhibitory enhancement of Wnt/β-catenin signaling. The as-prepared SAL NCs exhibited excellent size distribution, stability, and improved water solubility. In vitro cellular uptake and in vivo fluorescence imaging studies showed that SAL NCs increased cellular uptake efficiency compared with free SAL. As a result, SAL NCs exhibited significant higher cytotoxicity, 1.5-3 times better Wnt inhibitory effect, and 10 times better cancer stem cell inhibitory effect than free SAL. Furthermore, compared with free SAL, SAL NCs exhibited 2 times better anti-colon tumor effect in APC^min/+ transgenic mice through oral administration. Our results indicated that SAL NCs with enhanced cellular internalization and tumor tissue accumulation may be a promising agent for colorectal cancer management.

Doxorubicin-loaded iron oxide nanoparticles for glioblastoma therapy: a combinational approach for enhanced delivery of nanoparticles

Although doxorubicin (DOX) is an effective anti-cancer drug with cytotoxicity in a variety of different tumors, its effectiveness in treating glioblastoma multiforme (GBM) is constrained by insufficient penetration across the blood–brain barrier (BBB). In this study, biocompatible magnetic iron oxide nanoparticles (IONPs) stabilized with trimethoxysilylpropyl-ethylenediamine triacetic acid (EDT) were developed as a carrier of DOX for GBM chemotherapy. The DOX-loaded EDT-IONPs (DOX-EDT-IONPs) released DOX within 4 days with the capability of an accelerated release in acidic microenvironments. The DOX-loaded EDT-IONPs (DOX-EDT-IONPs) demonstrated an efficient uptake in mouse brain-derived microvessel endothelial, bEnd.3, Madin–Darby canine kidney transfected with multi-drug resistant protein 1 (MDCK-MDR1), and human U251 GBM cells. The DOX-EDT-IONPs could augment DOX’s uptake in U251 cells by 2.8-fold and significantly inhibited U251 cell proliferation. Moreover, the DOX-EDT-IONPs were found to be effective in apoptotic-induced GBM cell death (over 90%) within 48 h of treatment. Gene expression studies revealed a significant downregulation of TOP II and Ku70, crucial enzymes for DNA repair and replication, as well as MiR-155 oncogene, concomitant with an upregulation of caspase 3 and tumor suppressors i.e., p53, MEG3 and GAS5, in U251 cells upon treatment with DOX-EDT-IONPs. An in vitro MDCK-MDR1-GBM co-culture model was used to assess the BBB permeability and anti-tumor activity of the DOX-EDT-IONPs and DOX treatments. While DOX-EDT-IONP showed improved permeability of DOX across MDCK-MDR1 monolayers compared to DOX alone, cytotoxicity in U251 cells was similar in both treatment groups. Using a cadherin binding peptide (ADTC5) to transiently open tight junctions, in combination with an external magnetic field, significantly enhanced both DOX-EDT-IONP permeability and cytotoxicity in the MDCK-MDR1-GBM co-culture model. Therefore, the combination of magnetic enhanced convective diffusion and the cadherin binding peptide for transiently opening the BBB tight junctions are expected to enhance the efficacy of GBM chemotherapy using the DOX-EDT-IONPs. In general, the developed approach enables the chemotherapeutic to overcome both BBB and multidrug resistance (MDR) glioma cells while providing site-specific magnetic targeting.

Gold Nanoparticles in Glioma Theranostics

Despite many endeavors to treat malignant gliomas in the last decades, the median survival of patients has not significantly improved. The infiltrative nature of high-grade gliomas and the impermeability of the blood-brain barrier to the most therapeutic agents remain major hurdles, impeding an efficacious treatment. Theranostic platforms bridging diagnosis and therapeutic modalities aim to surmount the current limitations in diagnosis and therapy of glioma. Gold nanoparticles (AuNPs) due to their biocompatibility and tunable optical properties have widely been utilized for an assortment of theranostic purposes. In this Review, applications of AuNPs as imaging probes, drug/gene delivery systems, radiosensitizers, photothermal transducers, and multimodal theranostic agents in malignant gliomas are discussed. This Review also aims to provide a perspective on cancer theranostic applications of AuNPs in future clinical trials.

Salinomycin-Loaded Iron Oxide Nanoparticles for Glioblastoma Therapy

Salinomycin is an antibiotic introduced recently as a new and effective anticancer drug. In this study, magnetic iron oxide nanoparticles (IONPs) were utilized as a drug carrier for salinomycin for potential use in glioblastoma (GBM) chemotherapy. The biocompatible polyethylenimine (PEI)-polyethylene glycol (PEG)-IONPs (PEI-PEG-IONPs) exhibited an efficient uptake in both mouse brain-derived microvessel endothelial (bEnd.3) and human U251 GBM cell lines. The salinomycin (Sali)-loaded PEI-PEG-IONPs (Sali-PEI-PEG-IONPs) released salinomycin over 4 days, with an initial release of 44% ± 3% that increased to 66% ± 5% in acidic pH. The Sali-IONPs inhibited U251 cell proliferation and decreased their viability (by approximately 70% within 48 h), and the nanoparticles were found to be effective in reactive oxygen species-mediated GBM cell death. Gene studies revealed significant activation of caspases in U251 cells upon treatment with Sali-IONPs. Furthermore, the upregulation of tumor suppressors (i.e., p53, Rbl2, Gas5) was observed, while TopII, Ku70, CyclinD1, and Wnt1 were concomitantly downregulated. When examined in an in vitro blood–brain barrier (BBB)-GBM co-culture model, Sali-IONPs had limited penetration (1.0% ± 0.08%) through the bEnd.3 monolayer and resulted in 60% viability of U251 cells. However, hyperosmotic disruption coupled with an applied external magnetic field significantly enhanced the permeability of Sali-IONPs across bEnd.3 monolayers (3.2% ± 0.1%) and reduced the viability of U251 cells to 38%. These findings suggest that Sali-IONPs combined with penetration enhancers, such as hyperosmotic mannitol and external magnetic fields, can potentially provide effective and site-specific magnetic targeting for GBM chemotherapy.

Recent advances in the combination delivery of drug for leukemia and other cancers

Introduction: Combination therapy has been explored for its potential to reduce or eliminate multidrug resistance in treating different types of cancer including leukemia. Nutraceutical, small molecular drugs, and small interfering ribonucleic acid (siRNA) are some of the effective drugs. In order to avoid off-site targeting, reduce the dosage required, and increase the half-life of the drug in the circulation system, drug delivery vehicles, such as nanoparticles and microfibers have been explored.Areas covered: This review summarizes various therapies utilized in treating leukemia based on their effectiveness in inducing protein inhibition and/or apoptosis. In particular, treatment effectiveness using combination therapy using various devices is addressed. Recently explored drug delivery methods are reviewed, providing examples and their applications in cancer treatment. The drug listing, delivery systems classifications, along with the general modeling approach in this review, provide, to a full extent, a basis for cancer drug delivery future studies.Expert opinion: The reviewer's opinion tackles the potential of using a multi-delivery system to deliver multiple drugs, providing better control upon drug release and targeting. Both local and systemic delivery are considered and explored for their potential targets. Researchers are advised to pre-consider all aspects associated with their desired delivery method.

Doxycycline, salinomycin, monensin and ivermectin repositioned as cancer drugs

Chemotherapy is one of the standard methods for the treatment of malignant tumors. It aims to cause lethal damage to cellular structures, mainly DNA. Noteworthy, in recent years discoveries of novel anticancer agents from well-known antibiotics have opened up new treatment pathways for several cancer diseases. The aim of this review article is to describe new applications for the following antibiotics: doxycycline (DOX), salinomycin (SAL), monensin (MON) and ivermectin (IVR) as they are known to show anti-tumor activity, but have not yet been introduced into standard oncological therapy. To date, these agents have been used for the treatment of a broad-spectrum of bacterial and parasitic infectious diseases and are widely available, which is why they were selected. The data presented here clearly show that the antibiotics mentioned above should be recognised in the near future as novel agents able to eradicate cancer cells and cancer stem cells (CSCs) across several cancer types.