Overcoming blood brain barrier with a dual purpose Temozolomide loaded Lactoferrin nanoparticles for combating glioma (SERP-17-12433).
ABSTRACT: Targeted delivery of drugs to the brain is challenging due to the restricted permeability across the blood brain barrier (BBB). Gliomas are devastating cancers and their positive treatment outcome using Temozolomide (TMZ) is limited due to its short plasma half-life, systemic toxicity and limited access through the blood-brain barrier (BBB). Nanoparticles made of Lactoferrin (Lf) protein, have been shown to enhance the pharmacological properties of drugs. Here, we report the specific ability of Lf nanoparticles to cross BBB and target over-expressed Lf receptors on glioma for enhanced TMZ delivery. TMZ-loaded Lf nanoparticles (TMZ-LfNPs) were prepared by our previously reported sol-oil method. While the Lf protein in the NP matrix aids in transcytosis across the BBB and preferential tumor cell uptake, the pH responsiveness leads to TMZ release exclusively in the tumor microenvironment. Delivery through LfNPs results in an enhanced and sustained intracellular concentration of TMZ in GL261 cells in vitro along with improving its in vivo pharmacokinetics and brain accumulation. TMZ-LfNPs treatment results in a significant reduction of tumor volume, higher tumor cell apoptosis and improved median survival in glioma bearing mice. These results demonstrate that LfNPs present an efficient TMZ delivery platform for an effective treatment of gliomas.
Project description:Focused ultrasound (FUS) exposure with the presence of microbubbles has been shown to transiently open the blood-brain barrier (BBB), and thus has potential to enhance the delivery of various kinds of therapeutic agents into brain tumors. The purpose of this study was to assess the preclinical therapeutic efficacy of FUS-BBB opening for enhanced temozolomide (TMZ) delivery in glioma treatment. FUS exposure with microbubbles was delivered to open the BBB of nude mice that were either normal or implanted with U87 human glioma cells. Different TMZ dose regimens were tested, ranging from 2.5 to 25 mg/kg. Plasma and brain samples were obtained at different time-points ranging from 0.5 to 4 hours, and the TMZ concentration within samples was quantitated via a developed LC-MS/MS procedure. Tumor progression was followed with T2-MRI, and animal survival and brain tissue histology were conducted. Results demonstrated that FUS-BBB opening caused the local TMZ accumulation in the brain to increase from 6.98 to 19 ng/mg. TMZ degradation time in the tumor core was found to increase from 1.02 to 1.56 hours. Improved tumor progression and animal survival were found at different TMZ doses (up to 15% and 30%, respectively). In conclusion, this study provides preclinical evidence that FUS-BBB opening increases the local concentration of TMZ to improve the control of tumor progression and animal survival, suggesting the potential for clinical application to improve current brain tumor treatment.
Project description:Penetration of the blood-brain barrier (BBB) and the blood-brain tumor barrier (BBTB) remains a significant challenge for the delivery of drugs in the treatment of glioma. Therefore, the development of targeted preparations with the ability to penetrate the BBB and BBTB, and target gliomas, is an important approach if we are to improve the efficacy of glioma treatment. In the current study, an active targeting preparation based on PLGA nanoparticles coated with erythrocyte membranes (RBCNPs) and dual-modified with DWSW and NGR peptide ligands (DWSW/NGR-RBCNPs). Euphorbia factor L1 (EFL1) extracted from euphorbiae semen was used as the model drug. The final nanoparticles were characterized by in vivo and in vitro tests. In vitro results showed that EFL1-loaded DWSW/NGR-RBCNPs were taken up by cells and had the ability to penetrate the BBB and BBTB and produce cytotoxic effects. Furthermore, in vivo studies in mice showed that when injected intravenously, these specialized NPs could enter the brain, target tumor tissue, and significantly extend life span. The results showed that dual-targeting EFL1-loaded DWSW/NGR-RBCNPs have significant potential as a nanotherapeutic tool for the treatment of brain glioma.
Project description:The addition of temozolomide (TMZ) to radiotherapy (RT) improves survival of patients with glioblastoma (GBM). However, TMZ?+?RT causes excess toxicity in patients. In this study, we prepared angiopep-2 (A2) modified lipid-poly (hypoxic radiosensitized polyprodrug) nanoparticles for TMZ delivery (A2-P(MIs)25/TMZ) to achieve synergistic effects against glioma. This A2-P(MIs)25/TMZ display highly promising advantages: (1) a hydrophobic P-(MIs)25 core where poorly water-soluble TMZ can be encapsulated; (2) nitro groups of the hydrophobic P-(MIs)25 core that are converted into hydrophilic amino groups (P(NH<sub>2</sub>s)25) under low oxygen conditions to mimic the oxygen-increased sensitization to RT; (3) a lipid monolayer at the interface of the core and the shell to modify the A2 (a specific ligand for low-density lipoprotein receptor-related protein-1 (LRP-1), which are expressed in the blood-brain barrier (BBB) and human glioma cells), thereby enhancing the drug encapsulation efficiency in glioma. These nanoparticles appear as a promising and robust nanoplatforms for TMZ and hypoxic cell radiosensitization delivery.
Project description:Systemically administered chemotherapeutic drugs are often ineffective in the treatment of invasive brain tumors due to poor therapeutic index. Within gliomas, despite the presence of heterogeneously leaky microvessels, dense extracellular matrix and high interstitial pressure generate a "blood-tumor barrier" (BTB), which inhibits drug delivery and distribution. Meanwhile, beyond the contrast MRI-enhancing edge of the tumor, invasive cancer cells are protected by the intact blood-brain barrier (BBB). Here, we tested whether brain-penetrating nanoparticles (BPN) that possess dense surface coatings of polyethylene glycol (PEG) and are loaded with cisplatin (CDDP) could be delivered across both the blood-tumor and blood-brain barriers with MR image-guided focused ultrasound (MRgFUS), and whether this treatment could control glioma growth and invasiveness. To this end, we first established that MRgFUS is capable of significantly enhancing the delivery of ~60nm fluorescent tracer BPN across the blood-tumor barrier in both the 9L (6-fold improvement) gliosarcoma and invasive F98 (28-fold improvement) glioma models. Importantly, BPN delivery across the intact BBB, just beyond the tumor edge, was also markedly increased in both tumor models. We then showed that a CDDP loaded BPN formulation (CDDP-BPN), composed of a blend of polyaspartic acid (PAA) and heavily PEGylated polyaspartic acid (PAA-PEG), was highly stable, provided extended drug release, and was effective against F98 cells in vitro. These CDDP-BPN were delivered from the systemic circulation into orthotopic F98 gliomas using MRgFUS, where they elicited a significant reduction in tumor invasiveness and growth, as well as improved animal survival. We conclude that this therapy may offer a powerful new approach for the treatment invasive gliomas, particularly for preventing and controlling recurrence.
Project description:Gliomas are the most common tumor of the central nervous system. However, the presence of the brain barrier blocks the effective delivery of drugs and leads to the treatment failure of various drugs. The development of a nanoparticle drug delivery system (NDDS) can solve this problem. In this review, we summarized the brain barrier (including blood-brain barrier (BBB), blood-brain tumor barriers (BBTB), brain-cerebrospinal fluid barrier (BCB), and nose-to-brain barrier), NDDS of glioma (such as passive targeting systems, active targeting systems, and environmental responsive targeting systems), and NDDS efficacy improvement strategies and deficiencies. The research prospect of drug-targeted delivery systems for glioma is also discussed.
Project description:The purpose of this study is to assess the preclinical therapeutic efficacy of magnetic resonance imaging (MRI)-monitored focused ultrasound (FUS)-induced blood-brain barrier (BBB) disruption to enhance Temozolomide (TMZ) delivery for improving Glioblastoma Multiforme (GBM) treatment. MRI-monitored FUS with microbubbles was used to transcranially disrupt the BBB in brains of Fisher rats implanted with 9L glioma cells. FUS-BBB opening was spectrophotometrically determined by leakage of dyes into the brain, and TMZ was quantitated in cerebrospinal fluid (CSF) and plasma by LC-MS\MS. The effects of treatment on tumor progression (by MRI), animal survival and brain tissue histology were investigated. Results demonstrated that FUS-BBB opening increased the local accumulation of dyes in brain parenchyma by 3.8-/2.1-fold in normal/tumor tissues. Compared to TMZ alone, combined FUS treatment increased the TMZ CSF/plasma ratio from 22.7% to 38.6%, reduced the 7-day tumor progression ratio from 24.03 to 5.06, and extended the median survival from 20 to 23 days. In conclusion, this study provided preclinical evidence that FUS BBB-opening increased the local concentration of TMZ to improve the control of tumor progression and animal survival, suggesting its clinical potential for improving current brain tumor treatment.
Project description:BACKGROUND: Effective transvascular delivery of nanoparticle-based chemotherapeutics across the blood-brain tumor barrier of malignant gliomas remains a challenge. This is due to our limited understanding of nanoparticle properties in relation to the physiologic size of pores within the blood-brain tumor barrier. Polyamidoamine dendrimers are particularly small multigenerational nanoparticles with uniform sizes within each generation. Dendrimer sizes increase by only 1 to 2 nm with each successive generation. Using functionalized polyamidoamine dendrimer generations 1 through 8, we investigated how nanoparticle size influences particle accumulation within malignant glioma cells. METHODS: Magnetic resonance and fluorescence imaging probes were conjugated to the dendrimer terminal amines. Functionalized dendrimers were administered intravenously to rodents with orthotopically grown malignant gliomas. Transvascular transport and accumulation of the nanoparticles in brain tumor tissue was measured in vivo with dynamic contrast-enhanced magnetic resonance imaging. Localization of the nanoparticles within glioma cells was confirmed ex vivo with fluorescence imaging. RESULTS: We found that the intravenously administered functionalized dendrimers less than approximately 11.7 to 11.9 nm in diameter were able to traverse pores of the blood-brain tumor barrier of RG-2 malignant gliomas, while larger ones could not. Of the permeable functionalized dendrimer generations, those that possessed long blood half-lives could accumulate within glioma cells. CONCLUSION: The therapeutically relevant upper limit of blood-brain tumor barrier pore size is approximately 11.7 to 11.9 nm. Therefore, effective transvascular drug delivery into malignant glioma cells can be accomplished by using nanoparticles that are smaller than 11.7 to 11.9 nm in diameter and possess long blood half-lives.
Project description:Chemotherapy outcomes for the treatment of glioma remains unsatisfactory due to the inefficient drug transport across the blood-brain barrier (BBB) and insufficient drug accumulation in the tumor region. Although many approaches, including various nanosystems, have been developed to promote the distribution of chemotherapeutics in the brain tumor, the delivery efficiency and the possible damage to the normal brain function still greatly restrict the clinical application of the nanocarriers. Therefore, it is urgent and necessary to discover more safe and effective BBB penetration and glioma-targeting strategies. In the present study, menthol, one of the strongest BBB penetration enhancers screened from traditional Chinese medicine, was conjugated to casein, a natural food protein with brain targeting capability. Then the conjugate self-assembled into the nanoparticles to load anti-cancer drugs. The nanoparticles were characterized to have appropriate size, spheroid shape and high loading drug capacity. Tumor spheroid penetration experiments demonstrated that penetration ability of menthol-modified casein nanoparticles (M-CA-NP) into the tumor were much deeper than that of unmodified nanoparticles. In vivo imaging further verified that M-CA-NPs exhibited higher brain tumor distribution than unmodified nanoparticles. The median survival time of glioma-bearing mice treated with HCPT-M-CA-NPs was significantly prolonged than those treated with free HCPT or HCPT-CA-NPs. HE staining of the organs indicated the safety of the nanoparticles. Therefore, the study combined the advantages of traditional Chinese medicine strategy with modern delivery technology for brain targeting, and provide a safe and effective approach for glioma therapy.
Project description:Malignant glioma is one of the most untreatable cancers because of the formidable blood-brain barrier (BBB), through which few therapeutics can penetrate and reach the tumors. Biologics have been booming in cancer therapy in the past two decades, but their application in brain tumor has long been ignored due to the impermeable nature of BBB against effective delivery of biologics. Indeed, it is a long unsolved problem for brain delivery of macromolecular drugs, which becomes the Holy Grail in medical and pharmaceutical sciences. Even assisting by targeting ligands, protein brain delivery still remains challenging because of the synthesis difficulties of ligand-modified proteins. Herein, we propose a rocket-like, multistage booster delivery system of a protein toxin, trichosanthin (TCS), for antiglioma treatment. TCS is a ribosome-inactivating protein with the potent activity against various solid tumors but lack of specific action and cell penetration ability. To overcome the challenge of its poor druggability and site-specific modification, intein-mediated ligation was applied, by which a gelatinase-cleavable peptide and cell-penetrating peptide (CPP)-fused recombinant TCS toxin can be site-specifically conjugated to lactoferrin (LF), thus constructing a BBB-penetrating, gelatinase-activatable cell-penetrating nanohybrid TCS toxin. This nanohybrid TCS system is featured by the multistage booster strategy for glioma dual-targeting delivery. First, LF can target to the BBB-overexpressing low-density lipoprotein receptor-related protein-1 (LRP-1), and assist with BBB penetration. Second, once reaching the tumor site, the gelatinase-cleavable peptide acts as a separator responsive to the glioma-associated matrix metalloproteinases (MMPs), thus releasing to the CPP-fused toxin. Third, CPP mediates intratumoral and intracellular penetration of TCS toxin, thereby enhancing its antitumor activity. The BBB penetration and MMP-2-activability of this delivery system were demonstrated. The antiglioma activity was evaluated in the subcutaneous and orthotopic animal models. Our work provides a useful protocol for improving the druggability of such class of protein toxins and promoting their <i>in-vivo</i> application for targeted cancer therapy.