In this paper, the potential use of either amine-functionalized or hydroxyl-functionalized magnesium ferrite (MgFe2O4) nanoparticles (NPs) as Congo red nanoad­sorbents is explored and compared. The amine-functionalized MgFe2O4 NPs (denoted as MgFe2O4–NH2 NPs) were synthesized by a one-pot coprecipitation method using ethanolamine as a surface modifier, while the hydroxyl-functionalized MgFe2O4 NPs (denoted as MgFe2O4–OH NPs) were prepared by a hydrothermal method. In general, both nanoadsorbents can be successfully produced without calcination and were found to possess superparamagnetic properties with high saturation magnetization (M s). In particular, MgFe2O4–OH NPs exhibit a higher M s value of ∼53 emu g–1, promoting the rapid separation ability of the NPs from the treated solution using an external permanent magnet. The Congo red removal performance of these nanoadsorbents was investigated as a function of the pH of the aqueous solution and contact time. The removal efficiency of Congo red by MgFe2O4–NH2 NPs was found to be ∼96% within 180 min at pH 6, while MgFe2O4–OH NPs provided a removal efficiency at ∼88% within 420 min at pH 8. In addition, the maximum adsorption capacities (q m) calculated using the Langmuir isotherm equation were found to be 71.4 and 67.6 mg g–1 for MgFe2O4–NH2 and MgFe2O4–OH NPs, respectively. The higher q m value of MgFe2O4–NH2 NPs could be attributed to stronger electrostatic interactions with the sulfonate groups of Congo red formed by larger numbers of protonated amine groups than protonated hydroxyl groups of the adsorbents under the performed conditions. Moreover, reusability experiments also revealed that MgFe2O4–NH2 NPs offered a higher removal efficiency than MgFe2O4–OH NPs for the same cycles tested. Therefore, this study demonstrates that MgFe2O4–NH2 NPs synthesized by a simple one-pot synthetic method are applicable as reusable magnetic nanoadsorbents for Congo red removal in current practice.

The three-dimensional (3D) cell culture model has been increasingly used to study cancer biology and screen for anticancer agents due to its close mimicry to in vivo tumor biopsies. In this study, 3D calcium(Ca)-alginate scaffolds were developed for human glioblastoma cell culture and an investigation of the responses to two anticancer agents, doxorubicin and cordycepin. Compared to the 2D monolayer culture, glioblastoma cells cultured on these 3D Ca-alginate scaffolds showed reduced cell proliferation, increased tumor spheroid formation, enhanced expression of cancer stem cell genes (CD133, SOX2, Nestin, and Musashi-1), and improved expression of differentiation potential-associated genes (GFAP and β-tubulin III).Additionally, the vascularization potential of the 3D glioblastoma cells was increased, as indicated by a higher expression of tumor angiogenesis biomarker (VEGF) than in the cells in 2D culture. To highlight the application of Ca-alginate scaffolds, the 3D glioblastomas were treated with anticancer agents, including doxorubicin and cordycepin. The results demonstrated that the 3D glioblastomas presented a greater resistance to the tested anticancer agents than that of the cells in 2D culture. In summary, the 3D Ca-alginate scaffolds for glioblastoma cells that were developed in this study offer a promising platform for anticancer agent screening and the discovery of drug-resistant mechanisms of cancer. K E Y W O R D S3D brain cancer, 3D calcium-alginate scaffolds, anticancer drug screening, brain cancer model, glioblastoma

Curcumin is a natural polyphenolic compound, isolated from Curcuma longa, and is an important ingredient of Asian foods. Curcumin has revealed its strong activities of anti-inflammatory, antioxidant, and anticancer. The efficient amount of curcumin could induce differentiation of stem cells and promoted the differentiation of glioma-initiating cells; however, the mechanisms underlying neural induction of curcumin have not yet been revealed. In this study, neural-inducing ability of curcumin was explored by using human pluripotent embryonal carcinoma cells, NTERA2 cells. The cells were induced toward neural lineage with curcumin and were compared with a standard neutralizing agent (retinoic acid). It was found that, after 14 days of the induction by curcumin, NTERA2 cells showed neuronal morphology and expressed neural-specific genes, including NeuroD, TUJ1, and PAX6. Importantly, curcumin activated neurogenesis of NTERA2 cells via the activation of autophagy, since autophagy-related genes, such as LC3, LAMP1, and ATG5, were upregulated along with the expression of neural genes. The inhibition of autophagy by chloroquine suppressed both autophagy and neural differentiation, highlighting the positive role of autophagy during neural differentiation. This autophagy-mediated neural differentiation of curcumin was found to be an ROS-dependent manner; curcumin induced ROS generation and suppressed antioxidant gene expression. Altogether, this study proposed the neural-inducing activity of curcumin via the regulation of autophagy within NTERA2 cells and underscored the health beneficial effects of curcumin for neurodegenerative disorders, such as Alzheimer's disease and Parkinson's disease.

Background/Aim: Among various types of brain tumors, glioblastoma is the most malignant and highly aggressive brain tumor that possesses a high resistance against anticancer drugs. To understand the underlined mechanisms of tumor drug resistance, a new and more effective research approach is required. The three dimensional (3D) in vitro cell culture models could be a potential approach to study cancer features and biology, as well as screen for anticancer agents due to the close mimicry of the 3D tumor microenvironments. Materials and Methods: With our developed 3D alginate scaffolds, Ilumina RNA-sequencing was used to transcriptomically analyze and compare the gene expression profiles between glioblastoma cells in traditional 2-dimensional (2D) monolayer and in 3D Ca-alginate scaffolds at day 14. To verify the reliability and accuracy of Illumina RNA-Sequencing data, ATP-binding cassette transporter genes were chosen for quantitative real-time polymerase chain reaction) verification. Results: The results showed that 7,411 and 3,915 genes of the 3D glioblastoma were up-regulated and down-regulated, respectively, compared with the 2D-cultured glioblastoma. Furthermore, the Kyoto Encyclopaedia of Genes and Genomes pathway analysis revealed that genes related to the cell cycle and DNA replication were enriched in the group of down-regulated gene. On the other hand, the genes involved in mitogen-activated protein kinase signaling, autophagy, drug metabolism through cytochrome P450, and ATP-binding cassette transporter were found in the up-regulated gene collection. Conclusion: 3D glioblastoma tumoroids might potentially serve as a powerful platform for exploring glioblastoma biology. They can also be valuable in anti-glioblastoma drug screening, as well as the identification of novel molecular targets in clinical treatment of human glioblastoma.

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