Zobrazení zdroje stránky Gustafssonstrickland7872

Epithelial ovarian cancer (EOC) is the most lethal gynecological malignancy, with an overall 5-year survival rate of only 30%. EOC is associated with drug resistance, frequent recurrence, and poor prognosis. A major contributor toward drug resistance might be cancer stem cells (CSCs), which may remain after chemotherapy. Here, we aimed to find therapeutic agents that target ovarian CSCs. We performed a high-throughput screening using the Clinical Compound Library with a sphere culture of A2780 EOCs. Poziotinib, a pan-human epidermal growth factor receptor (HER) inhibitor, decreased sphere formation, viability, and proliferation, and induced G1 cell cycle arrest and apoptosis in ovarian CSCs. In addition, poziotinib suppressed stemness and disrupted downstream signaling of Wnt/β-catenin, Notch, and Hedgehog pathways, which contribute to many characteristics of CSCs. Interestingly, HER4 was overexpressed in ovarian CSCs and Poziotinib reduced the phosphorylation of STAT5, AKT, and ERK, which are regulated by HER4. Our results suggest that HER4 may be a promising therapeutic target for ovarian CSCs, and that poziotinib may be an effective therapeutic option for the prevention of ovarian cancer recurrence. SARS-CoV-2 causes the recent global COVID-19 public health emergency. ACE2 is the receptor for both SARS-CoV-2 and SARS-CoV. To predict the potential host range of SARS-CoV-2, we analyzed the key residues of ACE2 for recognizing S protein. We found that most of the selected mammals including pets (dog and cat), pangolin and Circetidae mammals remained the most of key residues for association with S protein from SARS-CoV and SARS-CoV-2. The interaction interface between cat/dog/pangolin/Chinese hamster ACE2 and SARS-CoV/SARS-CoV-2 S protein was simulated through homology modeling. We identified that N82 in ACE2 showed a closer contact with SARS-CoV-2 S protein than M82 in human ACE2. Our finding will provide important insights into the host range of SARS-CoV-2 and a new strategy to design an optimized ACE2 for SARS-CoV-2 infection. Gadolinium-based contrast agents (GBCAs) are widely used in clinical magnetic resonance imaging (MRI). Free gadolinium ions (Gd3+) released from GBCAs potentially increase the risk of GBCA-related toxicity. However, the cellular responses to Gd3+ and the underlying mechanisms responsible for protection against Gd3+ remain poorly understood. Recently, autophagy has been considered a cell survival mechanism against various toxic metals. Here, we investigated the relationship between Gd3+ and autophagy, as well as the effect of autophagy inhibition on the survival of cells exposed to Gd3+. We found that the increased expression of microtubule-associated protein 1 light chain 3 (LC3)-II, a marker protein of autophagy, in Gd3+-exposed human embryonic kidney 293 (HEK293) cells. Moreover, we found a greater accumulation of LC3-II after exposure to an autophagy inhibitor, chloroquine (CQ), combined with Gd3+ than that after exposure to CQ alone, suggesting that Gd3+ activated autophagy in HEK293&nbsp;cells. Furthermore, we found that Gd3+ reduced cell viability, which was more pronounced after CQ treatment. Our findings indicated that autophagy exerted a cytoprotective effect against Gd3+ toxicity, suggesting a potential link between autophagy and GBCA-associated adverse events. Echinacoside, a small molecule derived from the natural herbs Cistanche and Echinacea, shows effective anticancer abilities, but the mechanism remains unclear. By using colony formation, scratch, and transwell assays in MDA-MB-231 breast cancer cells, we confirmed the anti-breast cancer ability of Echinacoside in&nbsp;vitro. In addition, we found that Echinacoside can dose-dependently reduce phosho-LRP6, total LRP6, phosho-Dvl2, active β-catenin, and total β-catenin protein expression level in MDA-MB-231 and MDA-MB-468&nbsp;cells by western blot. We also detected well-known Wnt targets genes, including LEF1, CD44, and cyclin D1 by real-time PCR and western blot, and Echinacoside significantly shows inhibition effect in these two breast cancer cell lines. Furthermore, we investigated its anti-breast cancer ability in an MDA-MB-231 xenograft model in&nbsp;vivo. Echinacoside treatment significantly reduced tumor growth, which was accompanied by a reduction in Wnt/β-catenin signaling. In summary, our results demonstrate that Echinacoside can effectively inhibit Wnt/β-catenin signaling, and therefore, it may be a promising therapeutic target to treat breast cancer. Upon detection of viral DNA, the cytoplasmic DNA sensor cyclic GMP-AMP (cGAMP) synthase (cGAS) utilizes GTP and ATP as substrates to synthesize the second messenger molecule 2'3'cyclic GMP-AMP (cGAMP), which binds to the ER-associated adaptor protein MITA/STING to signal innate antiviral response to DNA virus. How the cGAS-MITA pathways are post-translationally regulated is not fully understood. In this study, we identified the tyrosine kinase CSK as a positive regulator of cGAS-MITA mediated innate antiviral response. CSK-deficiency inhibits DNA virus-triggered induction of downstream antiviral effector genes. Following DNA virus infection, CSK phosphorylates MITA at Y240 and Y245, which is important for its activation. These results suggest that CSK plays a role in modulating innate immune response to DNA virus. Collagen type I (Col I) is one of the major extracellular matrix proteins in the cancer tissue. Previously, we have reported that Col I induces epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) resistance by mTOR activation through Akt and ERK1/2 independent pathway. In this study, we aimed to elucidate the molecular mechanism of Col I induced EGFR-TKI resistance. First, we demonstrated the uptake of fluorescently labeled Col I by EGFR-mutated lung cancer cell line PC-9&nbsp;cells using confocal microscopy and flow cytometry. Metabolome analysis revealed that the metabolic profiles of PC-9&nbsp;cells was influenced by Col I treatment. Uptake of Col I into PC-9&nbsp;cells was not inhibited by MMP inhibitor, GM6001, and endocytosis inhibitors, Pitstop2 and Dyngo4a; however, macropinocytosis inhibitor EIPA prevented its uptake. Moreover, the combination of EIPA and EGFR-TKI abrogated Col I-induced EGFR-TKI resistance in PC-9&nbsp;cells. Inhibition of Rac1, which is essential for micropinocytosis, also decreased the uptake of Col I in PC-9&nbsp;cells and restored their sensitivity to EGFR-TKI. Thus, EGFR mutated lung cancer cells could develop EGFR-TKI resistance by Col I uptake by macropinocytosis route. Autophagy is an essential process to maintain cell survival and homeostasis under various stress conditions. Here, we report that lysine-specific demethylase 3A (KDM3A) plays an important role in starvation-induced autophagy. Using Kdm3a knockout mice, we demonstrate that KDM3A is crucial for proper hepatic autophagy in&nbsp;vivo. Hepatic mRNA expression analysis and ChIP assay in WT and Kdm3a knockout mouse livers reveal that KDM3A activates autophagy genes by reducing histone H3K9me2 levels upon fasting. Together, our finding represents previously unidentified function of KDM3A as a key regulator of autophagy, implicating potential therapeutic approaches for autophagy-related diseases. The Notch signaling pathway is highly conserved and essential in animal development and tissue homeostasis. Regulation of Notch signaling is a crucial process for human health. Ligands initiate a signal cascade by binding to Notch receptors expressed on the neighboring cell. Notch receptors interact with ligands through their epidermal growth factor-like repeats (EGF repeats). Most EGF repeats are modified by O-glycosylation with residues, such as O-linked N-acetylglucosamine (O-GlcNAc), O-fucose, and O-glucose. A recent study revealed the distinct roles of these O-glycans in ligand binding, processing, and trafficking of Notch receptors. In particular, O-GlcNAc glycans are essential for Delta-like (DLL) ligand-mediated Notch signaling. In this study, we showed that O-GlcNAc promotes Notch1 trafficking to the cell surfaces under the condition that O-fucose and O-glucose are removed from consecutive EGF repeats of Notch1. Through in&nbsp;vitro experiments, we showed that O-GlcNAc mediates the stability of EGF domains in the same manner as O-fucose and O-glucose. Thus, O-GlcNAc on EGF domains possesses a shared function in the stability of EGF domains and Notch1 trafficking. Nitric oxide (NO)-mediated production of cyclic guanosine 3',5'-monophosphate (cGMP) is a crucial signaling pathway that controls a wide array of neuronal functions, including exocytotic neurotransmitter release. A novel nitrated derivative of cGMP, 8-nitro-cGMP, not only activates cGMP-dependent protein kinase (PKG), but also has membrane permeability and redox activity to produce superoxide and S-guanylated protein. To date, no studies have addressed the effects of 8-nitro-cGMP on exocytotic kinetics. Here, we aimed to assess the 8-nitro-cGMP-mediated modulation of the depolarization-evoked catecholamine release from bovine chromaffin cells. 8-Nitro-cGMP was produced in bovine chromaffin cells dependent on NO donor. Amperometric analysis revealed that 8-nitro-cGMP modulated the kinetic parameters of secretory spikes from chromaffin cells, particularly decreased the speed of individual spikes, resulting in a reduced amperometric spike height, slope β, and absolute value of slope γ. The modulatory effects were independent of the PKG signal and superoxide production. This is the first study to demonstrate that 8-nitro-cGMP modulates exocytosis and provide insights into a novel regulatory mechanism of exocytosis. INTRODUCTION The impact of minimally invasive endodontic procedures on root canal disinfection has not been determined. This ex&nbsp;vivo study compared root canal disinfection and shaping in teeth with contracted or conventional endodontic cavities. METHODS Mandibular incisors with oval-shaped canals were selected and anatomically matched based on micro-computed tomographic (micro-CT) analysis and distributed into 2 groups. Conservative and conventional access cavities were prepared, and the canals were contaminated with a pure culture of Enterococcus faecalis for 30 days. [https://www.selleckchem.com/products/LBH-589.html NVP-LBH589] Root canal preparation in both groups was performed using the XP-endo Shaper instrument (FKG Dentaire, La Chaux-de-Fonds, Switzerland) and 2.5% sodium hypochlorite irrigation. Intracanal bacteriologic samples were taken before and after preparation, and DNA was extracted and subjected to quantitative polymerase chain reaction. Micro-CT scans taken before and after preparation were used for shaping evaluation. Bacteriologic data were analyzed by the Poisson regression model and the chi-square test with Yates correction. Micro-CT data were analyzed by the Wilcoxon, Mann-Whitney, and Student t tests with the significance level set at 5%. RESULTS All initial samples were positive for E. faecalis. After preparation, the number of bacteria-positive samples was significantly higher in the contracted cavity group (25/29, 86%) than in the conventional cavity group (14/28, 50%) (P less then .01). Intergroup quantitative comparison showed that the reduction in bacterial counts was also significantly higher in the group of conventional cavities (P less then .01). Micro-CT data revealed no significant difference in the amount of unprepared areas between groups. CONCLUSIONS Our findings showed that although shaping using an adjustable instrument was similar between groups, disinfection was significantly compromised after root canal preparation of teeth with contracted endodontic cavities.