Reflectance structured illumination imaging of internalized cerium oxide nanoparticles modulating dose-dependent reactive oxygen species in breast cancer cells

Green synthesis of cerium oxide nanoparticles using zucchini peel extract for cytotoxic and photocatalytic properties

The aim of this study is the green synthesis of cerium oxide nanoparticles (CeO₂-NPs) using a natural capping agent and its application in water and wastewater treatment. This study presents the biosynthesis of CeO₂-NPs by the exertion of a green method using zucchini (Cucurbita pepo) extract as a capping agent. Synthesized CeO₂-NPs were distinguished through TGA/DTA, FT-IR, XRD, FESEM/TEM and EDX/PSA, and DRS procedures. According to the XRD pattern of NPs, the crystallinity structure was a face-centered cubic (fcc) with an Fm3m space group and the size was estimated at 30 nm. The spherical morphology of NPs was confirmed through FESEM/TEM images. In the following, the photocatalytic property of NPs was investigated by the decolorization of methylene blue (MB) dye within UV-A light. Also, the cytotoxicity of NPs on the CT26 cell line was evaluated through the MTT test, and no toxicity was observed in the results, which indicates their biocompatibility.

Cerium oxide nanoparticles exert antitumor effects and enhance paclitaxel toxicity and activity against breast cancer cells

Cerium oxide nanoparticles (CeONPs) displayed cytotoxic properties against some cancer cells. However, there is very limited data about the possible antitumoral potential of them in breast cancer cells when used alone and/or together with a chemotherapeutic drug. We investigated the effects of CeONPs alone or in combination with paclitaxel (PAC) on healthy or carcinoma breast cells. After human breast cancer cells (MCF-7) treated with CeONPs alone or together with PAC for 24, 48, and 72 h, the effects of CeONPs on cell viability, apoptosis, migration, and adhesion were investigated. All cell viability and IC50 values of CeONPs and PAC treatments in healthy breast cells (HTERT-HME1) were higher than MCF-7 cells. They showed higher cytotoxicity against MCF-7 cells. CeONPs (10, 20, and 30 mM) and/or abraxane (AB) (2 μM) significantly decreased cell viability values in MCF-7 cells. All CeONPs concentrations increased the number of apoptotic MCF-7 cells. CeONPs (20 and 30 mM) alone or in combination with AB for 72 h treatment also significantly increased the apoptosis in compared to AB alone. CeONPs and/or AB can significantly inhibit the migratory ability of breast cancer cells. The migration rates in co-treated groups with CeONPs and AB were lower than CeONPs treatments. Higher concentrations of CeONPs alone or together with AB inhibited cell adhesion. Our results showed CeONPs can increase cytotoxicity and apoptosis and decrease cell migration and cell adhesion when used alone or together with AB. Therefore, combination of chemotherapeutics with CeONPs may provide a good strategy against cancer.

Preparation and Surface Characterization of Cerium Dioxide for Separation of 68Ge/68Ga and Other Medicinal Radionuclides

The overall need for the preparation of new medicinal radionuclides has led to the fast development of new sorption materials, extraction agents, and separation methods. Inorganic ion exchangers, mainly hydrous oxides, are the most widely used materials for the separation of medicinal radionuclides. One of the materials that has been studied for a long time is cerium dioxide, a competitive sorption material for the broadly used titanium dioxide. In this study, cerium dioxide was prepared through calcination of ceric nitrate and fully characterized using X-ray powder diffraction (XRPD), infrared spectrometry (FT-IR), scanning and transmission electron microscopy (SEM and TEM), thermogravimetric and differential thermal analysis (TG and DTA), dynamic light scattering (DLS), and analysis of surface area. In order to estimate the sorption mechanism and capacity of the prepared material, characterization of surface functional groups was carried out using acid-base titration and mathematical modeling. Subsequently, the sorption capacity of the prepared material for germanium was measured. It can be stated that the prepared material is prone to exchange anionic species in a wider range of pH than titanium dioxide. This characteristic makes the material superior as a matrix in 68Ge/68Ga radionuclide generators, and its suitability should be further studied in batch, kinetic, and column experiments.

Recent Developments in Metallic Nanomaterials for Cancer Therapy, Diagnosing and Imaging Applications

Cancer continues to represent a global health concern, imposing an ongoing need to research for better treatment alternatives. In this context, nanomedicine seems to be the solution to existing problems, bringing unprecedented results in various biomedical applications, including cancer therapy, diagnosing, and imaging. As numerous studies have uncovered the advantageous properties of various nanoscale metals, this review aims to present metal-based nanoparticles that are most frequently employed for cancer applications. This paper follows the description of relevant nanoparticles made of metals, metal derivatives, hybrids, and alloys, further discussing in more detail their potential applications in cancer management, ranging from the delivery of chemotherapeutics, vaccines, and genes to ablative hyperthermia therapies and theranostic platforms.

Internalized Nanoceria Modify the Radiation-Sensitivity Profile of MDA MB231 Breast Carcinoma Cells

Owing to its unique redox properties, cerium oxide (nanoceria) nanoparticles have been shown to confer either radiosensitization or radioprotection to human cells. We investigated nanoceria's ability to modify cellular health and reactive oxygen species (ROS) at various absorbed doses (Gray) of ionizing radiation in MDA-MB231 breast carcinoma cells. We used transmission electron microscopy to visualize the uptake and compartmental localization of nanoceria within cells at various treatment concentrations. The effects on apoptosis and other cellular health parameters were assessed using confocal fluorescence imaging and flow cytometry without and with various absorbed doses of ionizing radiation, along with intracellular ROS levels. Our results showed that nanoceria were taken up into cells mainly by macropinocytosis and segregated into concentration-dependent large aggregates in macropinosomes. Confocal imaging and flow cytometry data showed an overall decrease in apoptotic cell populations in proportion to increasing nanoparticle concentrations. This increase in cellular health was observed with a corresponding reduction in ROS at all tested absorbed doses. Moreover, this effect appeared pronounced at lower doses compared to unirradiated or untreated populations. In conclusion, internalized nanoceria confers radioprotection with a corresponding decrease in ROS in MDA-MB231 cells, and this property confers significant perils and opportunities when utilized in the context of radiotherapy.

Strategies for the treatment of breast cancer: from classical drugs to mathematical models

Breast cancer is one of the most common cancers and generally affects women. It is a heterogeneous disease that presents different entities, different biological characteristics, and differentiated clinical behaviors. With this in mind, this literature review had as its main objective to analyze the path taken from the simple use of classical drugs to the application of mathematical models, which through the many ongoing studies, have been considered as one of the reliable strategies, explaining the reasons why chemotherapy is not always successful. Besides, the most commonly mentioned strategies are immunotherapy, which includes techniques and therapies such as the use of antibodies, cytokines, antitumor vaccines, oncolytic and genomic viruses, among others, and nanoparticles, including metallic, magnetic, polymeric, liposome, dendrimer, micelle, and others, as well as drug reuse, which is a process by which new therapeutic indications are found for existing and approved drugs. The most commonly used pharmacological categories are cardiac, antiparasitic, anthelmintic, antiviral, antibiotic, and others. For the efficient development of reused drugs, there must be a process of exchange of purposes, methods, and information already available, and for their better understanding, computational mathematical models are then used, of which the methods of blind search or screening, based on the target, knowledge, signature, pathway or network and the mechanism to which it is directed, stand out. To conclude it should be noted that these different strategies can be applied alone or in combination with each other always to improve breast cancer treatment.

Bifunctional Diblock DNA-Mediated Synthesis of Nanoflower-Shaped Photothermal Nanozymes for a Highly Sensitive Colorimetric Assay of Cancer Cells

The activity of a nanozyme is closely related to its surface area-to-volume ratio and the surrounding temperature. To acquire highly active nanozymes, one-pot metallization-like synthesis of novel nanoflower-shaped photothermal nanostructures was conducted using polyadenine-containing diblock DNA as the scaffold. The nanoflower-shaped structures with a high surface area-to-volume ratio and photothermal performance exhibited excellent peroxidase-mimicking activity, and the biorecognition capability was retained by the capping agent of diblock DNA. The functionalized nanostructures were used for a proof-of-concept colorimetric assay of cancer cells in vitro. Upon incorporation of 808 nm laser irradiation, high sensitivity and selectivity for the cancer cell assay were achieved with the lowest detection level of 10 cells/mL. Relative to spherical gold nanostructures, the nanoflower-shaped photothermal nanozyme exhibited higher assay sensitivity, paving the way for the construction of nanozyme-based colorimetric sensors for point-of-care testing.