Publications by authors named "Shyang-guang Wang"

The quantitative analysis of cell surface antigens has attracted increasing attention due to the antigenic variation recognition that can facilitate early diagnoses. This paper presents a novel methodology based on the optical "cell-tearing" and the especially proposed "dilution regulations" to detect variations in cell surface antigens. The cell attaches to the corresponding antibody-coated slide surface.

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Pharmacologic intervention to affect the membrane lipid homeostasis of lipid rafts is a potent therapeutic strategy for cancer. Here we showed that gallic acid (GA) caused the complex formation of inactive Ras-related C3 botulinum toxin substrate 1 (Rac1)-phospho (p)-casein kinase 2 α (CK2α) (Tyr 255) in human tongue squamous carcinoma (TSC) cells, which disturbed the lipid raft membrane-targeting of phosphatidylinositol 3-kinase (PI3K)-Rac1-protein kinase B (Akt) signal molecules by inducing the association of p110α-free p85α with unphosphorylated phosphatase tensin homolog deleted on chromosome 10 (PTEN) in lipid rafts. The effects on induction of inactive Rac1-p-CK2α (Tyr 255) complex formation and attenuation of p-Akt (Ser 473), GTP-Rac1, glucose transporter-1 (GLUT-1) lipid raft membrane-targeting, and cell invasive activity by GA were counteracted either by CK2α short hairpin RNA or cellular-Src (c-Src) inhibitor PP1.

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The specialized cholesterol/sphingolipid-rich membrane domains termed lipid rafts are highly dynamic in the cancer cells, which rapidly assemble effector molecules to form a sorting platform essential for oncogenic signaling transduction in response to extra- or intracellular stimuli. Density-based membrane flotation, subcellular fractionation, cell surface biotinylation, and co-immunoprecipitation analyses of bichalcone analog ((E)-1-(4-Hydroxy-3-((4-(4-((E)-3-(pyridin-3-yl)acryloyl)phenyl)piperazin-1-yl)methyl)phenyl)-3-(pyridin-3-yl)prop-2-en-1-one (TSWU-BR4)-treated cancer cells showed dissociation between GRP78 and p85α conferring the recruitment of PTEN to lipid raft membranes associated with p85α. Ectopic expression of GRP78 could overcome induction of lipid raft membrane-associated p85α-unphosphorylated PTEN complex formation and suppression of GRP78PI3KAktGTP-Rac1-mediated and GRP78-regulated PERKNrf2 antioxidant pathway and cancer cell invasion by TSWU-BR4.

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Selective pharmacologic targeting of cell cycle regulators is a potent anti-cancer therapeutic strategy. Here, we show that caspase-3-mediated p21 cleavage involves p53 independent of triptolide (TPL)-induced S phase arrest in human type 1 nasopharyngeal carcinoma (NPC) cells. Coimmunoprecipitation studies demonstrated that TPL causes S phase cell cycle arrest by suppressing the formation of cyclin A-phosphor (p)-cyclin-dependent kinas 2 (CDK2) (Thr 39) complexes.

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Citrate is a key intermediate of the tricarboxylic acid cycle and acts as an allosteric signal to regulate the production of cellular ATP. An elevated cytosolic citrate concentration inhibits growth in several types of human cancer cells; however, the underlying mechanism by which citrate induces the growth arrest of cancer cells remains unclear. The results of this study showed that treatment of human pharyngeal squamous carcinoma (PSC) cells with a growth-suppressive concentration of citrate caused cell cycle arrest at the G/M phase.

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Caloric restriction activates sirtuin 1 (SIRT1) and induces a variety of metabolic effects that are beneficial for preventing age-related disease. The present study screened a commercially available used drug library to develop small molecule activators of SIRT1 as therapeutics for treatment of metabolic disorders. Using an in vitro fluorescence assay, the cancer therapeutic camptothecin increased SIRT1 enzymatic activity by 5.

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Iron or oxygen regulates the stability of hypoxia inducible factor-1α (HIF-1α). We investigated whether ferrous glycinate would affect HIF-1α accumulation, aerobic glycolysis and mitochondrial energy metabolism in human A549 lung cancer cells. Incubation of A549 cells with ferrous glycinate decreased the protein levels of HIF-1α, which was abrogated by proteosome inhibitor, or prolyl hydroxylase inhibitor.

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Healthcare professionals have a high risk of needlestick and sharps injuries (NSIs), which have a high potential for disease transmission. Ambulatory care follow up is essential, but is usually overlooked. This study aimed to investigate the annual and cumulative (age-, sex-, and subtype-specific) incidences of ambulatory care visits after NSIs.

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Aim: To investigate the effects of punicalagin, a polyphenol isolated from Punica granatum, on human U87MG glioma cells in vitro.

Methods: The viability of human U87MG glioma cells was evaluated using MTT assay. Cell cycle was detected with flow cytometry analysis.

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Background: A shift in glucose metabolism from oxidative phosphorylation to anaerobic glycolysis is the biochemical hallmark of malignant cancer cells.

Methods: In the present study, we demonstrated that Nodal stimulated the expression of glycolytic enzymes and decreased reliance on mitochondrial oxidative phosphorylation in human glioma cancer cells. The shift in glucose metabolism was mediated by induction of the hypoxia-inducible factor (HIF).

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Article Synopsis
  • Monacolin K, a natural form of lovastatin from Monascus spp., inhibits cholesterol synthesis by targeting key enzymes.
  • Monacolin K activates the SIRT1/AMPK pathway in HepG2 cells, leading to changes in protein expression that promote lipid breakdown while inhibiting lipid production.
  • The study also found that the effects of monacolin K on lipid reduction were reversed by inhibitors of SIRT1 and AMPK, confirming its mechanism of action in reducing lipid accumulation.
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Background: Musculoskeletal disorders (MSDs) represent the leading causes of occupational injuries among nursing staff. This population-based study was designed to assess the incidence and age-specific incidence of MSDs among a Taiwanese nurse cohort compared with non-nurses.

Description: Data from the Taiwan National Health Insurance Research Database were used to identify MSDs in the study population.

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Fenofibrate, a fibric acid derivative, is known to possess lipid-lowering effects. Although fenofibrate may activate peroxisome proliferator-activated receptor (PPAR)α and regulate the transcription of several genes, the underlying mechanisms are poorly understood. In this study, we demonstrated that incubation of C2C12 myotubes with fenofibrate increased adipose triglyceride lipase (ATGL) expression and suppressed fatty acid synthase (FAS) level, thereby decreasing intracellular triglyceride accumulation when cells were incubated at high-glucose condition.

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Aloe-emodin (AE), extracted from the rhizome of Rheum palmatum, has an anti-proliferative effect on different human cancer cell lines. Nonetheless, the underlying mechanism by which AE inhibits nasopharyngeal carcinoma (NPC) cell invasion is still unclear. The results of this study show that treatment of NPC cells with growth suppressive concentrations of AE caused cell cycle arrest at the S-G(2)/M phase.

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Aloe-emodin (AE), a natural, biologically active compound from the rhizome of Rheum palmatum, has been shown to induce apoptosis in several cancer cell lines in vitro. However, its molecular mechanism of action in the apoptosis induction of human nasopharyngeal carcinoma (NPC) cells has not been explored. This study shows that AE induced G(2)/M phase arrest by increasing levels of cyclin B1 bound to Cdc2, and also caused an increase in apoptosis of NPC cells, which was characterized by morphological changes, nuclear condensation, DNA fragmentation, caspase-3 activation, cleavage of poly (ADP-ribose) polymerase (PARP) and increased sub-G(1) population.

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The human TAO kinase 1 (hTAOK1) is a member of the Ste20 group of kinases with the kinase domain located at the N-terminus. The rat homologue, originally named TAO1, has been demonstrated to be highly expressed in brain. In this study, the human TAO kinase 1 was transfected into human neuroblastoma SH-SY5Y cells and its biological effects on the cell morphology were observed by co-expressing the enhanced green fluorescent protein (EGFP).

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