Development of transferrin-modified poly(lactic-co-glycolic acid) nanoparticles for glioma therapy

Targeted Polymeric Nanoparticles as a Strategy for the Treatment of Glioblastoma: A Review

Glioblastoma multiforme is the most common and aggressive malignant tumor that affects the central nervous system, with high mortality and low survival. Glioblastoma multiforme treatment includes resection tumor surgery, followed by radiotherapy and chemotherapy adjuvants. However, the drugs used in chemotherapy present some limitations, such as the difficulty of crossing the bloodbrain barrier and resisting the cellular mechanisms of drug efflux. The use of polymeric nanoparticles has proven to be an effective alternative to circumvent such limitations, as it allows the exploration of a range of polymeric structures that can be modified in order to control the biodistribution and cytotoxic effect of the drug delivery systems. Nanoparticles are nanometric in size and allow the incorporation of targeting ligands on their surface, favoring the transposition of the blood-brain barrier and the delivery of the drug to specific sites, increasing the selectivity and safety of chemotherapy. The present review has described the characteristics of chitosan, poly(vinyl alcohol), poly(lactic-coglycolic acid), poly(ethylene glycol), poly(β-amino ester), and poly(ε-caprolactone), which are some of the most commonly used polymers in the manufacture of nanoparticles for the treatment of glioblastoma multiforme. In addition, some of the main targeting ligands used in these nanosystems are presented, such as transferrin, chlorotoxin, albumin, epidermal growth factor, and epidermal growth factor receptor blockers, explored for the active targeting of antiglioblastoma agents.

Effect of Transferrin-Modified Fe3O4 Nanoparticle Targeted Delivery miR-15a-5p Combined With Photothermal Therapy on Lung Cancer

BACKGROUND

Existing studies have shown that transferrin receptor (TfR) is highly expressed on the surface of lung cancer cells, and nanoparticles (NPs) have been widely used as delivery vehicles. The aim of this study was to investigate the effect of the targeted delivery of Fe3O4 NPs modified with transferrin (Tf) compared with photothermal treatment for lung cancer.

METHODS

The morphology and properties of Fe3O4 NPs modified with Tf were tested by internal morphological characterization experiments including transmission electron microscopy, particle size meter infrared spectrometer and other experiments. The delivery of materials was investigated by cell proliferation and apoptosis experiments, and western blot experiment was used to detect yes-associated protein 1(YAP1) protein expression changes after delivering miR-15a-5p. In addition, animal models were constructed to further explore the targeting properties of the material.

RESULTS

The results demonstrated that the nanomaterial has good stability and targeting properties. Meanwhile, we also discovered that the miR-15a-5p carried by NPs can inhibit cell growth after its entry to the lung cancer cells. The effect became more evident when the nanomaterials were assisted with laser therapy, as verified by in vivo and in vitro experiments. In terms of the related mechanism, miR-15a-5p inhibited YAP1 expression, which affected cell proliferation and apoptosis.

CONCLUSION

In this study, Fe3O4 NPs modified with Tf delivered miR-15a-5p in combination with photothermal therapy for lung cancer. In future research, the targeted delivery of Tf and the photothermal synergy of nanomaterials will provide a theoretical basis for cancer treatment.

Surface Modification of Mesoporous Silica Nanoparticles for Application in Targeted Delivery Systems of Antitumour Drugs

The problem of tumour therapy has attracted the attention of many researchers for many decades. One of the promising strategies for the development of new dosage forms to improve oncology treatment efficacy and minimise side effects is the development of nanoparticle-based targeted transport systems for anticancer drugs. Among inorganic nanoparticles, mesoporous silica deserves special attention due to its outstanding surface properties and drug-loading capability. This review analyses the various factors affecting the cytotoxicity, cellular uptake, and biocompatibility of mesoporous silica nanoparticles (MSNs), constituting a key aspect in the development of safe and effective drug delivery systems. Special attention is paid to technological approaches to chemically modifying MSNs to alter their surface properties. The stimuli that regulate drug release from nanoparticles are also discussed, contributing to the effective control of the delivery process in the body. The findings emphasise the importance of modifying MSNs with different surface functional groups, bio-recognisable molecules, and polymers for their potential use in anticancer drug delivery systems.

Dual-targeted transferrin and AS1411 aptamer conjugated micelles for improved therapeutic efficacy and imaging of brain cancer

Brain tumors represent an aggressive form of cancer, posing significant challenges in achieving complete remission. Development of advanced therapies is crucial for improving clinical outcomes in cancer patients. This study aimed to create a novel treatment approach using dual-targeted transferrin (TF) and AS1411 conjugated micelles, designed to enhance therapeutic effectiveness of docetaxel (DTX) and facilitate gadolinium (Gd) based imaging in brain cancer. Micelles were prepared using a slightly modified solvent-casting method, and the dual-targeting ligands were attached to the micelle's surface through a physical adsorption process. Average particle size of micelles ranged from 117.49 ± 3.90-170.38 ± 3.39 nm, with a low polydispersity index. Zeta potential ranged from - 1.5 ± 0.02 to - 18.7 ± 0.04 mV. Encapsulation efficiency of DTX in micelles varied from 92.64 ± 4.22-79.77 ± 4.13 %. Simultaneously, encapsulation of Gd in micelles was found to be 48.27 ± 3.18-58.52 ± 3.17, respectively. In-vitro drug release studies showed a biphasic sustained release profile, with DTX and Gd release continuing up to 72 h with their t50 % at 4.95, 11.29, and 24.14 h for GDTP, GDTP-TF and GDTP-TF-AS1411 micelles, respectively. Cytotoxicity effect of GDTP-TF-AS1411 micelles has shown significant improvement (P < 0.001) and reduced IC50 value up to 0.19 ± 0.14 μg/ml compared to Taxotere® (2.73 ± 0.73 μg/ml). Theranostic study revealed higher accumulation of GDTP-TF and GDTP-TF-AS1411 micelles free GD treated animal brains. The AUC of GDTP-TF-AS1411 micelles exhibited 23.79 ± 17.82 μg.h/ml higher than Taxotere® (14.14 ± 10.59 μg.h/ml). These findings direct enhanced effectiveness in brain cancer therapy leading to improved therapeutics in brain cancer patients. The combined targeted ligands and therapeutic agents strategy can direct advancement in brain cancer therapy and offer improved therapy for patients.

Nanoparticle Strategies to Improve the Delivery of Anticancer Drugs across the Blood-Brain Barrier to Treat Brain Tumors

Primary brain and central nervous system (CNS) tumors are a diverse group of neoplasms that occur within the brain and spinal cord. Although significant advances in our understanding of the intricate biological underpinnings of CNS neoplasm tumorigenesis and progression have been made, the translation of these discoveries into effective therapies has been stymied by the unique challenges presented by these tumors' exquisitely sensitive location and the body's own defense mechanisms (e.g., the brain-CSF barrier and blood-brain barrier), which normally protect the CNS from toxic insult. These barriers effectively prevent the delivery of therapeutics to the site of disease. To overcome these obstacles, new methods for therapeutic delivery are being developed, with one such approach being the utilization of nanoparticles. Here, we will cover the current state of the field with a particular focus on the challenges posed by the BBB, the different nanoparticle classes which are under development for targeted CNS tumor therapeutics delivery, and strategies which have been developed to bypass the BBB and enable effective therapeutics delivery to the site of disease.

Focused Delivery of Chemotherapy to Augment Surgical Management of Brain Tumors

Chemotherapy as an adjuvant therapy that has largely failed to significantly improve outcomes for aggressive brain tumors; some reasons include a weak blood brain barrier penetration and tumor heterogeneity. Recently, there has been interest in designing effective ways to deliver chemotherapy to the tumor. In this review, we discuss the mechanisms of focused chemotherapies that are currently under investigation. Nanoparticle delivery demonstrates both a superior permeability and retention. However, thus far, it has not demonstrated a therapeutic efficacy for brain tumors. Convection-enhanced delivery is an invasive, yet versatile method, which appears to have the greatest potential. Other vehicles, such as angiopep-2 decorated gold nanoparticles, polyamidoamine dendrimers, and lipid nanostructures have demonstrated efficacy through sustained release of focused chemotherapy and have either improved cell death or survival in humans or animal models. Finally, focused ultrasound is a safe and effective way to disrupt the blood brain barrier and augment other delivery methods. Clinical trials are currently underway to study the safety and efficacy of these methods in combination with standard of care.

Polymeric Nanoparticles in Brain Cancer Therapy: A Review of Current Approaches

Translation of novel therapies for brain cancer into clinical practice is of the utmost importance as primary brain tumors are responsible for more than 200,000 deaths worldwide each year. While many research efforts have been aimed at improving survival rates over the years, prognosis for patients with glioblastoma and other primary brain tumors remains poor. Safely delivering chemotherapeutic drugs and other anti-cancer compounds across the blood-brain barrier and directly to tumor cells is perhaps the greatest challenge in treating brain cancer. Polymeric nanoparticles (NPs) are powerful, highly tunable carrier systems that may be able to overcome those obstacles. Several studies have shown appropriately-constructed polymeric NPs cross the blood-brain barrier, increase drug bioavailability, reduce systemic toxicity, and selectively target central nervous system cancer cells. While no studies relating to their use in treating brain cancer are in clinical trials, there is mounting preclinical evidence that polymeric NPs could be beneficial for brain tumor therapy. This review includes a variety of polymeric NPs and how their associated composition, surface modifications, and method of delivery impact their capacity to improve brain tumor therapy.

Recent Advances in the Surface Functionalization of PLGA-Based Nanomedicines

Therapeutics are habitually characterized by short plasma half-lives and little affinity for targeted cells. To overcome these challenges, nanoparticulate systems have entered into the disease arena. Poly(d,l-lactide-co-glycolide) (PLGA) is one of the most relevant biocompatible materials to construct drug nanocarriers. Understanding the physical chemistry of this copolymer and current knowledge of its biological fate will help in engineering efficient PLGA-based nanomedicines. Surface modification of the nanoparticle structure has been proposed as a required functionalization to optimize the performance in biological systems and to localize the PLGA colloid into the site of action. In this review, a background is provided on the properties and biodegradation of the copolymer. Methods to formulate PLGA nanoparticles, as well as their in vitro performance and in vivo fate, are briefly discussed. In addition, a special focus is placed on the analysis of current research in the use of surface modification strategies to engineer PLGA nanoparticles, i.e., PEGylation and the use of PEG alternatives, surfactants and lipids to improve in vitro and in vivo stability and to create hydrophilic shells or stealth protection for the nanoparticle. Finally, an update on the use of ligands to decorate the surface of PLGA nanomedicines is included in the review.

Combined Ultrasound Treatment with Transferrin-Coupled Nanoparticles Improves Active Targeting of 4T1 Mammary Carcinoma Cells

Objective: Conventional chemotherapy remains the mainstay treatment for many breast cancer patients, but its effectiveness is limited by toxic side effects. Incorporating drugs such as docetaxel into nanoparticle medicines can reduce toxicity but further improvements are required. To facilitate more active tumor targeting, we prepared transferrin-docetaxel-loaded pegylated-albumin nanoparticles (Tf-PEG-DANPS). Methods: The growth inhibitory effects and the ability of unmodified DANPS or PEG-DANPS to induce apoptosis in 4T1 mouse mammary cancers were compared to Tf-PEG-DANPS treatment using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry. These experiments were extended in vivo to the intravenous treatment of 4T1 tumors where PEG-DANPS was compared to Tf-PEG-DANPS alone or Tf-PEG-DANPS combined with ultrasound (US + Tf-PEG-DANPS). Histological assessments using hematoxylin and eosin (HE) sections were performed to examine antitumor activity, metastasis to lung and liver, and body weight measurements taken as an indicator of toxicity. Results: MTT experiments show that, in the normal and low concentration interval, the inhibition ability of the Tf-PEG-DANPS is higher than that of other drug-giving groups, and the flow cytometry show that the proportion of induced apoptosis in each given group is 2.88%, 42.95%, 48.23%, and 57.89%, indicating that the Tf-PEG-DANPS group has more significant ability to induce apoptosis than other drug-giving groups. From the pathological HE staining and semiquantitative analysis, US+Tf-PEG-DANPS can effectively inhibit the growth of breast cancer transplanted tumors and suppress metastases, it also has smaller toxic side effects on mice. Conclusion: The antitumor effect of US+Tf-PEG-DANPS represents an effective combination that exhibits increased antitumor activity and metastasis reduction with an improved side-effect profile.

Improving temozolomide biopharmaceutical properties in glioblastoma multiforme (GBM) treatment using GBM-targeting nanocarriers

Glioblastoma multiforme (GBM) is the most common primary brain cancer. GBM has aggressive development, and the pharmacological treatment remains a challenge due to GBM anatomical characteristics' (the blood-brain barrier and tumor microenvironment) and the increasing resistance to marketed drugs, such as temozolomide (TMZ), the first-line drug for GBM treatment. Due to physical-chemical properties such as short half-life time and the increasing resistance shown by GBM cells, high doses and repeated administrations are necessary, leading to significant adverse events. This review will discuss the main molecular mechanisms of TMZ resistance and the use of functionalized nanocarriers as an efficient and safe strategy for TMZ delivery. GBM-targeting nanocarriers are an important tool for the treatment of GBM, demonstrating to improve the biopharmaceutical properties of TMZ and repurpose its use in anti-GBM therapy. Technical aspects of nanocarriers will be discussed, and biological models highlighting the advantages and effects of functionalization strategies in TMZ anti-GBM activity. Finally, conclusions regarding the main findings will be made in the context of new perspectives for the treatment of GBM using TMZ as a chemotherapy agent, improving the sensibility and biological anti-tumor effect of TMZ through functionalization strategies.

Thermosensitive magnetic nanoparticles exposed to alternating magnetic field and heat-mediated chemotherapy for an effective dual therapy in rat glioma model

The goal of this study was to develop a new method based on Oncothermia with concomitant use of the temozolomide (TMZ)-loaded magnetic nanoparticles conjugated with folic acid (TMZ/MNPs-FA) and alternative magnetic field (AMF) and evaluate its efficacy in the treatment of C6 glioma in rats. TMZ/MNPs-FA were prepared and evaluated for their size, surface charge, magnetic saturation, hemolysis and in vitro AMF-triggered release. The glioma rat models were treated with free TMZ, MNPs-FA and TMZ/MNPs-FA in the presence or absence of AMF (43 °C). The results confirmed that a combinatorial therapy consisting of AFM hyperthermia and thermosensitive TMZ/MNPs-FA could significantly suppress tumor growth, increase survival rate and promote apoptosis (P < 0.0001). Therefore, this treatment strategy may be a powerful modality for treatment of cancer, as the thermal and mechanical effects of magnetic nanoparticles exposed to AMF can increase the therapeutic efficacy of conventional chemotherapy.