Search results for "way"
showing 10 items of 3116 documents
Polyphosphate as a metabolic fuel in Metazoa: A foundational breakthrough invention for biomedical applications
2015
In animals, energy-rich molecules like ATP are generated in the intracellular compartment from metabolites, e.g. glucose, taken up by the cells. Recent results revealed that inorganic polyphosphates (polyP) can provide an extracellular system for energy transport and delivery. These polymers of multiple phosphate units, linked by high-energy phosphoanhydride bonds, use blood platelets as transport vehicles to reach their target cells. In this review it is outlined how polyP affects cell metabolism. It is discussed that polyP influences cell activity in a dual way: (i) as a metabolic fuel transferring metabolic energy through the extracellular space; and (ii) as a signaling molecule that amp…
Temporal quantitative phosphoproteomics of ADP stimulation reveals novel central nodes in platelet activation and inhibition
2017
Adenosine diphosphate (ADP) enhances platelet activation by virtually any other stimulant to complete aggregation. It binds specifically to the G-protein-coupled membrane receptors P2Y1 and P2Y12, stimulating intracellular signaling cascades, leading to integrin aIIbb3 activation, a process antagonized by endothelial prostacyclin. P2Y12 inhibitors are among the most successful antiplatelet drugs, however, show remarkable variability in efficacy. We reasoned whether a more detailed molecular understanding of ADP-induced protein phosphorylation could identify (1) critical hubs in platelet signaling toward aggregation and (2) novel molecular targets for antiplatelet treatment strategies. We ap…
Disruption of TCF/β-Catenin Binding Impairs Wnt Signaling and Induces Apoptosis in Soft Tissue Sarcoma Cells
2017
Abstract Soft tissue sarcomas (STS) are malignant tumors of mesenchymal origin and represent around 1% of adult cancers, being a very heterogeneous group of tumors with more than 50 different subtypes. The Wnt signaling pathway is involved in the development and in the regulation, self-renewal, and differentiation of mesenchymal stem cells, and plays a role in sarcomagenesis. In this study, we have tested pharmacologic inhibition of Wnt signaling mediated by disruption of TCF/β-catenin binding and AXIN stabilization, being the first strategy more efficient in reducing cell viability and downstream effects. We have shown that disruption of TCF/β-catenin binding with PKF118-310 produces in vi…
Intratumoral Heterogeneity and Longitudinal Changes in Gene Expression Predict Differential Drug Sensitivity in Newly Diagnosed and Recurrent Gliobla…
2020
Background: Inevitable recurrence after radiochemotherapy is the major problem in the treatment of glioblastoma, the most prevalent type of adult brain malignancy. Glioblastomas are notorious for a high degree of intratumor heterogeneity manifest through a diversity of cell types and molecular patterns. The current paradigm of understanding glioblastoma recurrence is that cytotoxic therapy fails to target effectively glioma stem cells. Recent advances indicate that therapy-driven molecular evolution is a fundamental trait associated with glioblastoma recurrence. There is a growing body of evidence indicating that intratumor heterogeneity, longitudinal changes in molecular biomarkers and spe…
Targeting chemoresistant colorectal cancer via systemic administration of a BMP7 variant
2020
Abstract Despite intense research and clinical efforts, patients affected by advanced colorectal cancer (CRC) have still a poor prognosis. The discovery of colorectal (CR) cancer stem cell (CSC) as the cell compartment responsible for tumor initiation and propagation may provide new opportunities for the development of new therapeutic strategies. Given the reduced sensitivity of CR-CSCs to chemotherapy and the ability of bone morphogenetic proteins (BMP) to promote colonic stem cell differentiation, we aimed to investigate whether an enhanced variant of BMP7 (BMP7v) could sensitize to chemotherapy-resistant CRC cells and tumors. Thirty-five primary human cultures enriched in CR-CSCs, includ…
Regulation of GSK-3 activity by curcumin, berberine and resveratrol: Potential effects on multiple diseases.
2017
Natural products or nutraceuticals promote anti-aging, anti-cancer and other health-enhancing effects. A key target of the effects of natural products may be the regulation of the PI3K/PTEN/Akt/mTORC1/GSK-3 pathway. This review will focus on the effects of curcumin (CUR), berberine (BBR) and resveratrol (RES), on the PI3K/PTEN/Akt/mTORC1/GSK-3 pathway, with a special focus on GSK-3. These natural products may regulate the pathway by multiple mechanisms including: reactive oxygen species (ROS), cytokine receptors, mirco-RNAs (miRs) and many others. CUR is present the root of turmeric (Curcuma longa). CUR is used in the treatment of many disorders, especially in those involving inflammatory p…
NRF2 through RPS6 Activation Is Related to Anti-HER2 Drug Resistance in HER2-Amplified Gastric Cancer
2019
Abstract Purpose: Despite the clinical advantage of the combination of trastuzumab and platinum-based chemotherapy in HER2-amplified tumors, resistance will eventually develop. The identification of molecular mechanisms related to primary and acquired resistance is needed. Experimental Design: We generated lapatinib- and trastuzumab-resistant clones deriving from two different HER2-amplified gastric cancer cell lines. Molecular changes such as protein expression and gene-expression profile were evaluated to detect alterations that could be related to resistance. Functional studies in vitro were corroborated in vivo. The translational relevance of our findings was verified in a patient cohor…
HMG-CoA reductase promotes protein prenylation and therefore is indispensible for T-cell survival.
2017
AbstractStatins are a well-established family of drugs that lower cholesterol levels via the competitive inhibition of the enzyme 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR). In addition, the pleiotropic anti-inflammatory effects of statins on T cells make them attractive as therapeutic drugs in T-cell-driven autoimmune disorders. Since statins do not exclusively target HMGCR and thus might have varying effects on different cell types, we generated a new mouse strain allowing for the tissue-specific deletion of HMGCR. Deletion of HMGCR expression in T cells led to a severe decrease in their numbers with the remaining cells displaying an activated phenotype, with an increased pro…
Lactate and Acidity in the Cancer Microenvironment
2020
Fermentative glycolysis, an ancient evolved metabolic pathway, is exploited by rapidly growing tissues and tumors but also occurs in response to the nutritional and energetic demands of differentiated tissues. The lactic acid it produces is transported across cell membranes through reversible H+/lactate−symporters (MCT1 and MCT4) and is recycled in organs as a major metabolic precursor of gluconeogenesis and an energy source. Concentrations of lactate in the tumor environment, investigated utilizing an induced metabolic bioluminescence imaging (imBI) technique, appear to be dominant biomarkers of tumor response to irradiation and resistance to treatment. Suppression of lactic acid formation…
From ancient herb to modern drug: Artemisia annua and artemisinin for cancer therapy.
2017
Artemisia annua L. is used throughout Asia and Africa as tea and press juice to treat malaria and related symptomes (fever, chills). Its active ingredient, artemisinin (ARS), has been developed as antimalarial drug and is used worldwide. Interestingly, the bioactivity is not restricted to malaria treatment. We and others found that ARS-type drugs also reveal anticancer in vitro and in vivo. In this review, we give a systematic overview of the literature published over the past two decades until the end of 2016. Like other natural products, ARS acts in a multi-specific manner against tumors. The cellular response of ARS and its derivatives (dihydroartemisinin, artesunate, artemether, arteeth…