Publications by authors named "Tsui-Yao Chen"

Depleting regulatory T cells (T cells) to counteract immunosuppressive features of the tumor microenvironment (TME) is an attractive strategy for cancer treatment; however, autoimmunity due to systemic impairment of their suppressive function limits its therapeutic potential. Elucidating approaches that specifically disrupt intratumoral T cells is direly needed for cancer immunotherapy. We found that CD36 was selectively upregulated in intrautumoral T cells as a central metabolic modulator.

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In the version of this article initially published, the bars were not aligned with the data points or horizontal axis labels in Fig. 5d, and the labels along each horizontal axis of Fig. 5j-l indicating the presence (+) or absence (-) of doxycycline (Dox) were incorrectly included with the labels below that axis.

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Immune checkpoint blockade therapy has shifted the paradigm for cancer treatment. However, the majority of patients lack effective responses due to insufficient T cell infiltration in tumors. Here we show that expression of mitochondrial uncoupling protein 2 (UCP2) in tumor cells determines the immunostimulatory feature of the tumor microenvironment (TME) and is positively associated with prolonged survival.

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Significant pesticide residues are among the most serious problems for sustainable agriculture. In the beekeeping environment, pesticides not only impact a honey bee's survival, but they also contaminate bee products. Taiwan's agricultural environment has suffered from pesticide stress that was higher than that found in Europe and America.

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Activated T cells engage aerobic glycolysis and anabolic metabolism for growth, proliferation, and effector functions. We propose that a glucose-poor tumor microenvironment limits aerobic glycolysis in tumor-infiltrating T cells, which suppresses tumoricidal effector functions. We discovered a new role for the glycolytic metabolite phosphoenolpyruvate (PEP) in sustaining T cell receptor-mediated Ca(2+)-NFAT signaling and effector functions by repressing sarco/ER Ca(2+)-ATPase (SERCA) activity.

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More than 10% of the world's population is chronically infected with HIV, hepatitis C virus (HCV) or hepatitis B virus (HBV), all of which can cause severe disease and death. These viruses persist in part because continuous antigenic stimulation causes the deterioration of virus-specific cytotoxic T lymphocyte (CTL) function and survival. Additionally, antiviral CTLs autonomously suppress their responses to limit immunopathology by upregulating inhibitory receptors such as programmed cell death 1 (PD-1).

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During the course of many chronic viral infections, the antiviral T cell response becomes attenuated through a process that is regulated in part by the host. While elevated expression of the immunosuppressive cytokine IL-10 is involved in the suppression of viral-specific T cell responses, the relevant cellular sources of IL-10, as well as the pathways responsible for IL-10 induction, remain unclear. In this study, we traced IL-10 production over the course of chronic lymphocytic choriomeningitis virus (LCMV) infection in an IL-10 reporter mouse line.

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B-Raf(V600E) inhibitors have been suggested to promote tumor regression with the help of host immunity, but this hypothesis has not been examined directly in detail. In this study, we profiled immunologic changes in the tumor microenvironment and tumor-infiltrating lymphocytes (TIL) in a B-RafV600E/Pten-driven murine model of melanoma after administration of the B-Raf(V600E) small molecule inhibitor PLX4720. In this model, we found that as tumors developed, they gradually acquired immunosuppressive features, including accumulation of regulatory T cells (Treg) and CD11b(+)/Gr-1(+) myeloid cells and loss of Th1 effector functions on CD4(+) TILs, such as CD40L and IFNγ expression.

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Tolerance to endotoxins that is triggered by prior exposure to Toll-like receptor (TLR) ligands provides a mechanism with which to dampen inflammatory cytokines. The receptor-interacting protein RIP140 interacts with the transcription factor NF-κB to regulate the expression of genes encoding proinflammatory cytokines. Here we found lipopolysaccharide stimulation of kinase Syk-mediated tyrosine phosphorylation of RIP140 and interaction of the NF-κB subunit RelA with RIP140.

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The physiological signal activating cytoplasmic accumulation of nuclear receptor interacting protein 140 (RIP140) in adipocytes was unclear. We uncover that endothelin-1 (ET-1) promotes cytoplasmic accumulation of RIP140 in 3T3-L1 adipocytes. We determine ET-1's signal transduction pathway in adipocytes, which is by activating ET(A) receptor-PLCβ-nuclear PKCε.

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We report the first example of a coordinated dual action of epidermal growth factor (EGF) in stimulating the nuclear-cytoplasmic export and translation of a select messenger RNA (mRNA). The effect of EGF is mediated by the RNA-binding protein Grb7 (growth factor receptor-bound protein 7), which serves as an adaptor for a specific mRNA-protein export complex and a translational regulator. Using the kappa-opioid receptor (OR [KOR]) as a model, we demonstrate that EGF activates nuclear SHP-2 (Src homology region 2-containing tyrosine phosphatase), which dephosphorylates Grb7 in the nucleus.

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Epidermal growth factor (EGF), a mitogen, also stimulates neurite extension during development, but the underlying mechanism is elusive. This study reveals a functional role for kappa opioid receptor (KOR) in EGF-stimulated neurite extension, and the underlying mechanism. EGF and activated EGF receptor (EGFR) levels are elevated in embryonic spinal cords during late gestation stages, with concurrent rise in protein levels of KOR and axon extension markers, growth-associated protein 43 (GAP43), and transient axonal glycoprotein-1 (TAG-1).

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Receptor-interacting protein 140 (RIP140), a nuclear receptor corepressor, is important for lipid and glucose metabolism. In adipocytes, RIP140 can be phosphorylated by protein kinase C epsilon (PKCvarepsilon), followed by arginine methylation, and exported to the cytoplasm. This study demonstrates for the first time a cytoplasmic function for RIP140: to counteract insulin-stimulated glucose transporter 4 (GLUT4) membrane partitioning and glucose uptake in adipocytes.

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Human coxsackievirus (CV) belongs to the picornavirus family, which consists of over 200 medically relevant viruses. In picornavirus, a chymotrypsin-like protease (3C(pro)) is required for viral replication by processing the polyproteins, and thus it is regarded as an antiviral drug target. A 3C-like protease (3CL(pro)) also exists in human coronaviruses (CoV) such as 229E and the one causing severe acute respiratory syndrome (SARS).

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Receptor-interacting protein 140 is a co-regulator for many transcription factors. Previous mass spectrometry studies showed that either phosphorylation or lysine acetylation of RIP140 directly enhanced its trans-repressive activity. In this study, we first identified p300 as a specific lysine acetyltransferase, and extracellular-signal-related kinase 2 (Erk2) as a specific kinase for threonine phosphorylation, of RIP140 in vivo.

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The ethanolic extract of I-Tiao Gung (GT-E) (Glycine tomentella root extract) was found to reduce the oxidative rate and prolonged lag phase of LDL in human (Homo sapiens) and tilapia (Oreochromis mossambicus). The in vivo effect of GT-E was determined using tilapia as a model. Hyperlipidemia and hypercholesterolemia were induced in fish by feeding commercial feed daily at 2% body mass for 8 weeks, or at 1% body mass for 12 weeks.

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I-Tiao-Gung, Glycine tomentella, has been used extensively as a traditional herbal medicine to relieve physical pain, but its bioactivity has not been studied systematically. Ninety-five percent ethanol extracts of G. tomentella (GT-E) showed antioxidant activity in human plasma by prolonging the lag phase (+Tlag) of Cu2+-induced LDL oxidation and were dose dependent.

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The anti-oxidative and anti-inflammatory activities of two different species of traditional Chinese medicines that shared the same name have been studied. The extracts of Glycine radix have higher activities in free radical-scavenging activity determined with DPPH, reduction in hemoglobin-catalyzed lipid auto-oxidation and inhibition of the lipoxygenase (LOX) and cyclooxygenase (COX)-catalyzed arachidonate oxidation compared to the activities of extract of Flemingia. One of the significant bioactive constituents of Glycine radix has been isolated and identified as daidzein.

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