Search results for "FACTOR"
showing 10 items of 17757 documents
2018
Abstract TNFα is a prominent proinflammatory cytokine and a critical mediator for the development of many types of cancer such as breast, colon, prostate, cervical, skin, liver, and chronic lymphocytic leukemia. Binding of TNFα to TNFR1 can lead to divergent signaling pathways promoting predominantly NF-κB activation but also cell death. We report here that the nitric oxide (NO) donor glyceryl trinitrate (GTN) converts TNFα, generated from immune cells or cancer cells stimulated by chemotherapy, into a prodeath mediator in colon and mammary cancer cells. GTN-mediated S-nitrosylation of cIAP1 on cysteines 571 and 574 inhibited its E3 ubiquitin ligase activity, which in turn reduced Lys63-lin…
Molecular Engineering Strategies Tailoring the Apoptotic Response to a MET Therapeutic Antibody
2020
The MET oncogene encodes a tyrosine kinase receptor involved in the control of a complex network of biological responses that include protection from apoptosis and stimulation of cell growth during embryogenesis, tissue regeneration, and cancer progression. We previously developed an antagonist antibody (DN30) inducing the physical removal of the receptor from the cell surface and resulting in suppression of the biological responses to MET. In its bivalent form, the antibody displayed a residual agonist activity, due to dimerization of the lingering receptors, and partial activation of the downstream signaling cascade. The balance between the two opposing activities is variable in different…
Yeast Cth2 protein represses the translation of ARE-containing mRNAs in response to iron deficiency
2018
In response to iron deficiency, the budding yeast Saccharomyces cerevisiae undergoes a metabolic remodeling in order to optimize iron utilization. The tandem zinc finger (TZF)-containing protein Cth2 plays a critical role in this adaptation by binding and promoting the degradation of multiple mRNAs that contain AU-rich elements (AREs). Here, we demonstrate that Cth2 also functions as a translational repressor of its target mRNAs. By complementary approaches, we demonstrate that Cth2 protein inhibits the translation of SDH4, which encodes a subunit of succinate dehydrogenase, and CTH2 mRNAs in response to iron depletion. Both the AREs within SDH4 and CTH2 transcripts, and the Cth2 TZF are es…
Tumor-Associated Fibroblasts Promote HER2-Targeted Therapy Resistance through FGFR2 Activation
2020
AbstractPurpose:Despite the therapeutic success of existing HER2-targeted therapies, tumors invariably relapse. This study aimed at identifying new mechanisms responsible for HER2-targeted therapy resistance.Experimental Design:We have used a platform of HER2-targeted therapy–resistant cell lines and primary cultures of healthy and tumor-associated fibroblasts (TAF) to identify new potential targets related to tumor escape from anti-HER2 therapies.Results:We have shown that TAFs promote resistance to HER2-targeted therapies. TAFs produce and secrete high levels of FGF5, which induces FGFR2 activation in the surrounding breast cancer cells. FGFR2 transactivates HER2 via c-Src, leading to res…
Nut1/Hos1 and Sas2/Rpd3 control the H3 acetylation of two different sets of osmotic stress-induced genes
2019
Epigenetic information is able to interact with the cellular environment and could be especially useful for reprograming gene expression in response to a physiological perturbation. In fact the genes induced or repressed by osmotic stress undergo significant changes in terms of the levels of various histone modifications, especially in the acetylation levels of histone H3. Exposing yeast to high osmolarity results in the activation of stress-activated protein kinase Hog1, which plays a central role in gene expression control. We evaluated the connection between the presence of Hog1 and changes in histone H3 acetylation in stress-regulated genes. We found a parallel increase in the acetylati…
HGF/MET Axis Induces Tumor Secretion of Tenascin-C and Promotes Stromal Rewiring in Pancreatic Cancer
2021
Simple Summary It has been previously shown that activation of the MET receptor by its ligand, the hepatocyte growth factor (HGF), modulates the tumor-stroma cross-talk in models of pancreatic cancer. We now wish to cast light on the molecular mechanisms by which this ligand/receptor pair sustains the interaction between cancer cells and the tumor microenviroment. To this end, we compared data obtained by large-scale analysis of gene expression in pancreatic cancer cells grown in the presence of HGF versus cells grown in the presence of HGF and treated with specific inhibitors of HGF/MET signaling. By clustering differentially expressed genes according to functional groups, we identified ca…
Targeting COPZ1 non-oncogene addiction counteracts the viability of thyroid tumor cells
2017
Abstract Thyroid carcinoma is generally associated with good prognosis, but no effective treatments are currently available for aggressive forms not cured by standard therapy. To find novel therapeutic targets for this tumor type, we had previously performed a siRNA-based functional screening to identify genes essential for sustaining the oncogenic phenotype of thyroid tumor cells, but not required to the same extent for the viability of normal cells (non-oncogene addiction paradigm). Among those, we found the coatomer protein complex ζ1 (COPZ1) gene, which is involved in intracellular traffic, autophagy and lipid homeostasis. In this paper, we investigated the mechanisms through which COPZ…
Chronic Sulforaphane Application Does Not Induce Resistance in Renal Cell Carcinoma Cells.
2018
Background/aim Since the natural compound sulforaphane (SFN) has been shown to stop tumor growth, renal cell carcinoma (RCC) patients often use this drug in addition to their prescribed oncotherapy. The aim of this study was to examine whether resistance to SFN may develop after long-term application. Materials and methods Several RCC cell lines were incubated with SFN for short periods of time (24-72 h) or long periods of time (8 weeks) and cell growth, proliferation, and cell-cycle proteins were analyzed. Results Both short- and long-term application of SFN distinctly reduced RCC cell growth and proliferation. However, differences in the distribution of cells in each phase of the cell cyc…
Inhibition of colon cancer growth by docosahexaenoic acid involves autocrine production of TNFα
2016
IF 7.932; International audience; The omega-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) has anti-inflammatory and anti-cancer properties. Among pro-inflammatory mediators, tumor necrosis factor a (TNF alpha) plays a paradoxical role in cancer biology with induction of cancer cell death or survival depending on the cellular context. The objective of the study was to evaluate the role of TNFa in DHA-mediated tumor growth inhibition and colon cancer cell death. The treatment of human colorectal cancer cells, HCT-116 and HCT-8 cells, with DHA triggered apoptosis in autocrine TNF alpha-dependent manner. We demonstrated that DHA-induced increased content of TNF alpha mRNA occurred thr…