Effects of iron oxide nanoparticles on biological responses and MR imaging properties in human mammary healthy and breast cancer epithelial cells

Biodistribution and Tumor Targeted Accumulation of Anti-CEA-loaded Iron Nanoparticles

INTRODUCTION

Active targeting of tumors by nanomaterials favors early diagnosis and the reduction of harsh side effects of chemotherapeuticals.

METHODS

We synthesized magnetic nanoparticles (64 nm; -40 mV) suspended in a magnetic fluid (MF) and decorated them with anti-carcinoembryonic antigen (MFCEA; 144 nm; -39 mV). MF and MFCEA nanoparticles were successfully radiolabeled with technetium-99m (99mTc) and intravenously injected in CEA-positive 4T1 tumor-bearing mice to perform biodistribution studies. Both 99mTc-MF and 99mTc-MFCEA had marked uptake by the liver and spleen, and the renal uptake of 99mTc-MFCEA was higher than that observed for 99mTc-MF at 20h. At 1 and 5 hours, the urinary excretion was higher for 99mTc-MF than for 99mTc-MFCEA.

RESULTS

These data suggest that anti-CEA decoration might be responsible for a delay in renal clearance. Regarding the tumor, 99mTc-MFCEA showed tumor uptake nearly two times higher than that observed for 99mTc-MFCEA. Similarly, the target-nontarget ratio was higher with 99mTc-MFCEA when compared to the group that received the 99mTc-MF.

CONCLUSION

These data validated the ability of active tumor targeting by the as-developed anti- CEA loaded nanoparticles and are very promising results for the future development of a nanodevice for the management of breast cancer and other types of CEA-positive tumors.

Unveiling Nanoparticles: Recent Approaches in Studying the Internalization Pattern of Iron Oxide Nanoparticles in Mono- and Multicellular Biological Structures

Nanoparticle (NP)-based solutions for oncotherapy promise an improved efficiency of the anticancer response, as well as higher comfort for the patient. The current advancements in cancer treatment based on nanotechnology exploit the ability of these systems to pass biological barriers to target the tumor cell, as well as tumor cell organelles. In particular, iron oxide NPs are being clinically employed in oncological management due to this ability. When designing an efficient anti-cancer therapy based on NPs, it is important to know and to modulate the phenomena which take place during the interaction of the NPs with the tumor cells, as well as the normal tissues. In this regard, our review is focused on highlighting different approaches to studying the internalization patterns of iron oxide NPs in simple and complex 2D and 3D in vitro cell models, as well as in living tissues, in order to investigate the functionality of an NP-based treatment.

Biomimetic Magnetoliposomes as Oxaliplatin Nanocarriers: In Vitro Study for Potential Application in Colon Cancer

Current chemotherapy for colorectal cancer (CRC) includes the use of oxaliplatin (Oxa), a first-line cytotoxic drug which, in combination with irinotecan/5-fluorouracil or biologic agents, increases the survival rate of patients. However, the administration of this drug induces side effects that limit its application in patients, making it necessary to develop new tools for targeted chemotherapy. MamC-mediated biomimetic magnetic nanoparticles coupled with Oxa (Oxa-BMNPs) have been previously demonstrated to efficiently reduce the IC₅₀ compared to that of soluble Oxa. However, their strong interaction with the macrophages revealed toxicity and possibility of aggregation. In this scenario, a further improvement of this nanoassembly was necessary. In the present study, Oxa-BMNPs nanoassemblies were enveloped in phosphatidylcholine unilamellar liposomes (both pegylated and non-pegylated). Our results demonstrate that the addition of both a lipid cover and further pegylation improves the biocompatibility and cellular uptake of the Oxa-BMNPs nanoassemblies without significantly reducing their cytotoxic activity in colon cancer cells. In particular, with the pegylated magnetoliposome nanoformulation (a) hemolysis was reduced from 5% to 2%, being now hematocompatibles, (b) red blood cell agglutination was reduced, (c) toxicity in white blood cells was eliminated. This study represents a truly stepforward in this area as describes the production of one of the very few existing nanoformulations that could be used for a local chemotherapy to treat CRC.

Cytotoxicity, cellular uptake and apoptotic responses in human coronary artery endothelial cells exposed to ultrasmall superparamagnetic iron oxide nanoparticles

Ultrasmall superparamagnetic iron oxide nanoparticles (USPION) possess reactive surfaces, are metabolized and exhibit unique magnetic properties. These properties are desirable for designing novel theranostic biomedical products; however, toxicity mechanisms of USPION are not completely elucidated. The goal of this study was to investigate cell interactions (uptake and cytotoxicity) of USPION using human coronary artery endothelial cells as a vascular cell model. Polyvinylpirrolidone-coated USPION were characterized: average diameter 17 nm (transmission electron microscopy [TEM]), average hydrodynamic diameter 44 nm (dynamic light scattering) and zeta potential -38.75 mV. Cells were exposed to 0 (control), 25, 50, 100 or 200 μg/mL USPION. Concentration- and time-dependent cytotoxicity were observed after 3-6 hours through 24 hours of exposure using Alamar Blue and Real-Time Cell Electronic Sensing assays. Cell uptake was evaluated by imaging using live-dead confocal microscopy, actin and nuclear fluorescent staining, and TEM. Phase-contrast, confocal microscopy, and TEM imaging showed significant USPION internalization as early as 3 hours after exposure to 25 μg/mL. TEM imaging demonstrated particle internalization in secondary lysosomes with perinuclear localization. Three orthogonal assays were conducted to assess apoptosis. TUNEL staining demonstrated a marked increase in fragmented DNA, a response pathognomonic of apoptosis, after a 4-hour exposure. Cells subjected to agarose gel electrophoresis exhibited degraded DNA 3 hours after exposure. Caspase-3/7 activity increased after a 3-hour exposure. USPION uptake resulted in cytotoxicity involving apoptosis and these results contribute to further mechanistic understanding of the USPION toxicity in vitro in cardiovascular endothelial cells.

Design and synthesis of aptamer AS1411-conjugated EG@TiO2@Fe2O3nanoparticles as a drug delivery platform for tumor-targeted therapy

AS1411@GMBS@EG@TiO₂@Fe₂O₃nanoparticle is an effective and safe pH-responsive sustained release system for targeted drug delivery into nucleolin-positive cells.

Microwave-Assisted Synthesis of SPION-Reduced Graphene Oxide Hybrids for Magnetic Resonance Imaging (MRI)

Magnetic resonance imaging (MRI) is a useful tool for disease diagnosis and treatment monitoring. Superparamagnetic iron oxide nanoparticles (SPION) show good performance as transverse relaxation (T2) contrast agents, thus facilitating the interpretation of the acquired images. Attachment of SPION onto nanocarriers prevents their agglomeration, improving the circulation time and efficiency. Graphene derivatives, such as graphene oxide (GO) and reduced graphene oxide (RGO), are appealing nanocarriers since they have both high surface area and functional moieties that make them ideal substrates for the attachment of nanoparticles. We have employed a fast, simple and environmentally friendly microwave-assisted approach for the synthesis of SPION-RGO hybrids. Different iron precursor/GO ratios were used leading to SPION, with a median diameter of 7.1 nm, homogeneously distributed along the RGO surface. Good relaxivity (r2*) values were obtained in MRI studies and no significant toxicity was detected within in vitro tests following GL261 glioma and J774 macrophage-like cells for 24 h with SPION-RGO, demonstrating the applicability of the hybrids as T2-weighted MRI contrast agents.

Nanoparticles as contrast agents for brain nuclear magnetic resonance imaging in Alzheimer's disease diagnosis

Nuclear Magnetic Resonance Imaging (MRI) of amyloid plaques is a powerful non-invasive approach for the early and accurate diagnosis of Alzheimer's disease (AD) along with clinical observations of behavioral changes and cognitive impairment. The present article aims at giving a critical and comprehensive review of recent advances in the development of nanoparticle-based contrast agents for brain MRI. Nanoparticles considered for the MRI of AD must comply with a highly stringent set of requirements including low toxicity and the ability to cross the blood-brain-barrier. In addition, to reach an optimal signal-to-noise ratio, they must exhibit a specific ability to target amyloid plaques, which can be achieved by grafting antibodies, peptides or small molecules. Finally, we propose to consider new directions for the future of MRI in the context of Alzheimer's disease, in particular by enhancing the performances of contrast agents and by including therapeutic functionalities following a theranostic strategy.

Enhanced antitumor activity of surface-modified iron oxide nanoparticles and an α-tocopherol derivative in a rat model of mammary gland carcinosarcoma

Maghemite (γ-Fe2O3) nanoparticles were obtained by coprecipitation of ferrous and ferric salts in an alkaline medium followed by oxidation; the nanoparticles were coated with poly(N,N-dimethylacrylamide) (PDMA) and characterized by transmission electron microscopy, attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering, thermogravimetric and elemental analyses, and magnetic measurements in terms of particle morphology, size, polydispersity, amount of coating, and magnetization, respectively. The effects of α-tocopherol (Toc) and its phenolic (Toc-6-OH) and acetate (Toc-6-Ac) derivatives on Fe2+ release from γ-Fe2O3@PDMA, as well as from γ-Fe2O3 and CuFe2O4 nanoparticles (controls), were examined in vitro using 1,10-phenanthroline. The presence of tocopherols enhanced spontaneous Fe2+ release from nanoparticles, with Toc-6-OH exhibiting more activity than neat Toc. All of the nanoparticles tested were found to initiate blood lipid oxidation in a concentration-dependent manner, as determined by analysis of 2-thiobarbituric acid reactive species. Wistar rats with Walker-256 carcinosarcoma (a model of mammary gland carcinosarcoma) received Toc-6-Ac, magnetic nanoparticles, or their combination per os, and the antitumor activity of each treatment was determined in vivo. γ-Fe2O3@PDMA nanoparticles exhibited increased antitumor activity compared to both commercial CuFe2O4 particles and the antitumor drug doxorubicin. Moreover, increased antitumor activity was observed after combined administration of γ-Fe2O3@PDMA nanoparticles and Toc-6-Ac; however, levels of bilirubin, aspartate aminotransferase, and white bloods normalized and did not differ from those of the intact controls. The antitumor activity of the γ-Fe2O3 nanoparticles strongly correlated with Fe2+ release from the nanoparticles but not with nanoparticle-initiated lipid peroxidation in vitro.

The Food and Drug Administration Office of Women's Health: Impact of Science on Regulatory Policy: An Update

The U.S. Food and Drug Administration Office of Women's Health (FDA OWH) has supported women's health research for ∼20 years, funding more than 300 studies on women's health issues, including research on diseases/conditions that disproportionately affect women in addition to the evaluation of sex differences in the performance of and response to medical products. These important women's health issues are studied from a regulatory perspective, with a focus on improving and optimizing medical product development and the evaluation of product safety and efficacy in women. These findings have influenced industry direction, labeling, product discontinuation, safety notices, and clinical practice. In addition, OWH-funded research has addressed gaps in the knowledge about diseases and medical conditions that impact women across the life span such as cardiovascular disease, pregnancy, menopause, osteoporosis, and the safe use of numerous medical products.