Publications by authors named "Kyoung-Hwa Jung"

The multikinase inhibitor sorafenib is the standard first-line treatment for advanced hepatocellular carcinoma (HCC), but many patients become sorafenib-resistant (SR). This study investigated the efficacy of another kinase inhibitor, regorafenib (Rego), as a second-line treatment. We produced SR HCC cells, wherein the PI3K-Akt, TNF, cAMP, and TGF-beta signaling pathways were affected.

View Article and Find Full Text PDF

Rat primitive extraembryonic endoderm (pXEN) stem cell lines indefinitely preserve the characteristic features of the early extraembryonic endoderm (ExEn) in vitro, but require unknown serum factors and exhibit a hybrid (mesenchymal-epithelial) phenotype. We report two chemically defined conditions that differ by the addition of the cytokine leukemia inhibitory factor (Lif) and the β-catenin-stabilizing drug Chir99021, and enable permanent self-renewal as mesenchymal and epithelial morphotypes, respectively. The morphotypes are interconvertible and equipotent, as shown by the formation of well-differentiated organoids.

View Article and Find Full Text PDF

Background: Long non-coding RNAs (lncRNAs) are emerging as key modulators of inflammatory gene expression, but their roles in neuroinflammation are poorly understood. Here, we identified the inflammation-related lncRNAs and correlated mRNAs of the lipopolysaccharide (LPS)-treated human microglial cell line HMC3. We explored their potential roles and interactions using bioinformatics tools such as gene ontology (GO), kyoto encyclopedia of genes and genomes (KEGG), and weighted gene co-expression network analysis (WGCNA).

View Article and Find Full Text PDF

The epigenetic reader, bromodomain-containing 4 (BRD4), is overexpressed in hepatocellular carcinoma (HCC), and BRD4 inhibition is considered as a new therapeutic approach. The BRD inhibitor JQ1 is known to inhibit the enrichment of BRD4 at enhancer sites. Gene network analyses have implicated long non-coding RNAs (lncRNAs) in the effects of JQ1, but the precise molecular events remain unexplored.

View Article and Find Full Text PDF

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and poor prognosis. Emerging evidence suggests that epigenetic alterations play a crucial role in HCC, suggesting epigenetic inhibition as a promising therapeutic approach. Indeed, the bromodomain and extra-terminal (BET) inhibitors inhibit the proliferation and invasion of various cancers but still lack a strong mechanistic rationale.

View Article and Find Full Text PDF

The proto-oncogene MYC is important for development and cell growth, however, its abnormal regulation causes cancer. Recent studies identified distinct enhancers of MYC in various cancers, but any MYC enhancer(s) in hepatocellular carcinoma (HCC) remain(s) elusive. By analyzing H3K27ac enrichment and enhancer RNA (eRNA) expression in cultured HCC cells, we identified six putative MYC enhancer regions.

View Article and Find Full Text PDF

Hepatocellular carcinoma (HCC) is one of the most prevalent and poorly responsive cancers worldwide. Bromodomain and extraterminal (BET) inhibitors, such as JQ1 and OTX-015, inhibit BET protein binding to acetylated residues in histones. However, the physiological mechanisms and regulatory processes of BET inhibition in HCC remain unclear.

View Article and Find Full Text PDF

Microglia, resident macrophages of the brain that act as primary immune cells, play essential roles in innate immunity and neuroinflammatory pathologies. Microglial cells are rapidly activated in response to infection and inflammation/injury, associated with the expression of proinflammatory genes and secretion of cytokines. The bromodomain and extra-terminal (BET) inhibitor JQ1 has been shown to be an epigenetic agent that reduces inflammation.

View Article and Find Full Text PDF

Background: Toll-like receptor 4 (TLR4) ligands such as lipopolysaccharide (LPS) activate immunomodulatory functions and the migration of human mesenchymal stromal cells (hMSCs). Here, we study the migration-related gene expression of LPS-stimulated hMSCs and the role and regulation of one of the upregulated genes, encoding the interferon-induced transmembrane protein 1 (IFITM1).

Methods: Gene expression profiles were determined by whole-transcriptome analysis (RNA-seq) and quantitative real-time PCR (qRT-PCR).

View Article and Find Full Text PDF

Cultured rat primitive extraembryonic endoderm (pXEN) cells easily form free-floating multicellular vesicles , exemplifying a poorly studied type of morphogenesis. Here, we reveal the underlying mechanism and the identity of the vesicles. We resolve the morphogenesis into vacuolization, vesiculation and maturation, and define the molecular characteristics and requirements of each step.

View Article and Find Full Text PDF

This in vitro study examined the sealing ability of different desensitizing agents under a chemo-mechanical stress condition. For the study, a total of 144 extracted, caries-free human third molars were used to produce 1 mm-thick dentin discs. The specimens were divided randomly into four groups: Superseal (SS), Gluma (GL), Gluma Self-etch (GS), and Tooth Coat (TC).

View Article and Find Full Text PDF

Recent studies have reported an increased incidence of inflammatory bowel disease (IBD) in patients with pulmonary diseases. Despite clinical and epidemiological studies of the interplay between colitis and asthma, the diseases' related underlying mechanisms remain unclear. In this study, we evaluated the development of colitis in a model of allergic airway inflammation.

View Article and Find Full Text PDF

Mesenchymal stromal cells (MSCs) can potently regulate the functions of immune cells and are being investigated for the management of inflammatory diseases. Toll-like receptor 3 (TLR3)-stimulated human MSCs (hMSCs) exhibit increased migration and chemotaxis within and toward damaged tissues. However, the regulatory mechanisms underlying these migratory activities are unclear.

View Article and Find Full Text PDF

Mouse blastocysts contain the committed precursors of the extraembryonic endoderm (ExEn), which express the key transcription factor Oct4, depend on LIF/LIF-like factor-driven Jak/Stat signaling, and initially exhibit lineage plasticity. Previously described rat blastocyst-derived ExEn precursor-like cell lines (XENP cells/HypoSCs) also show these features, but equivalent mouse blastocyst-derived cell lines are lacking. We now present mouse blastocyst-derived cell lines, named primitive XEN (pXEN) cells, which share these and additional characteristics with the XENP cells/HypoSCs, but not with previously known mouse blastocyst-derived XEN cell lines.

View Article and Find Full Text PDF

Macrophages are the prime innate immune cells of the inflammatory response, and the combination of multiple signaling inputs derived from the recognition of host factors [e.g., interferon-g (IFN-γ)] and invading pathogen products (e.

View Article and Find Full Text PDF

The increased incidence of Crohn's disease in smokers has been recently reported, suggesting a strong association of cigarette smoke (CS) with colitis. However, the mechanism of the action of CS on colitis has not yet been explored. Here, we demonstrate that CS exposure is sufficient to induce colitis in mice.

View Article and Find Full Text PDF

This study examined the effects of different application times of sodium ascorbate (SA) on the bond strength of composite resin to bleached dentin. Specimens with an exposed dentin surface were divided into 3 groups according to the type of bleaching agent used: Group A, mixture of sodium perborate (SP) and distilled water (DW); Group B, mixture of SP and hydrogen peroxide (HP); control group, no bleaching. Each group was classified into 10 subgroups.

View Article and Find Full Text PDF

Ethanol is well known for its teratogenic effects during fetal development. Maternal alcohol consumption allows the developing fetus to experience the detrimental effects of alcohol exposure. Alcohol-mediated teratogenic effects can vary based on the dosage and the length of exposure.

View Article and Find Full Text PDF

The effects of dentin wetness on the bond strength and adhesive interface morphology of universal adhesives have been investigated using micro-tensile bond strength (μTBS) testing and confocal laser scanning microscopy (CLSM). Seventy-two human third molars were wet ground to expose flat dentin surfaces. They were divided into three groups according to the air-drying time of the dentin surfaces: 0 (without air drying), 5, and 10 s.

View Article and Find Full Text PDF

Histone-modifying enzymes are key players in the field of cellular differentiation. Here, we used GSK-J4 to profile important target genes that are responsible for neural differentiation. Embryoid bodies were treated with retinoic acid (10 μM) to induce neural differentiation in the presence or absence of GSK-J4.

View Article and Find Full Text PDF
Article Synopsis
  • The study examines how epigenetic factors influence gene expression and cell fate during the differentiation of cells, specifically focusing on the effects of ethanol on this process.
  • Researchers used a model of early neural differentiation to assess how 50mM ethanol alters mRNA expression, identifying 147 differentially expressed genes, with 78 up-regulated and 69 down-regulated.
  • The analysis highlighted important molecular regulators involved in protein modification and gene expression changes due to ethanol, establishing a platform for further research on ethanol's impact during cellular differentiation.
View Article and Find Full Text PDF
Article Synopsis
  • * GSK-J4 has immunosuppressive effects in macrophages and when tested on microglial cells, it selectively suppresses LPS-induced expression of various pro-inflammatory cytokines, chemokines, and genes related to inflammation.
  • * The study indicates that GSK-J4 modulates inflammatory gene expression by influencing key transcription factors and alterations in histone modifications, suggesting its potential as a therapeutic option for neuroinflammatory conditions.
View Article and Find Full Text PDF
Article Synopsis
  • Alcohol is a teratogenic agent that can lead to long-lasting developmental disorders, especially through epigenetic mechanisms like altered microRNA expression.
  • Non-coding RNAs, particularly microRNAs, play a crucial role in how alcohol affects gene expression, but the specific connections between these changes and diseases are not well understood.
  • This review compiles existing research on how alcohol disrupts microRNA expression during fetal development, aiming to guide future studies in prenatal alcohol toxicity and potential therapies.
View Article and Find Full Text PDF

Ethanol is well known as a teratogenic factor that is capable of inducing a wide range of developmental abnormalities if the developing fetus is exposed to it. Duration and dose are the critical parameters of exposure that affect teratogenic variation to the developing fetus. It is suggested that ethanol interferes with epigenetic processes especially DNA methylation.

View Article and Find Full Text PDF

Multiple studies have documented that Enhancer of zeste homolog 2 (EZH2) could play a role in inflammation and a wide range of malignancies; however, the underlying mechanisms remain largely unaddressed. Microglial activation is a key process in the production and release of numerous pro-inflammatory mediators that play important roles in inflammation and neurodegeneration in the central nervous system (CNS). Therefore, our aim was to investigate whether inhibition of EZH2 with the selective small molecule inhibitor EPZ-6438 protects against neonatal microglial activation.

View Article and Find Full Text PDF