bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gemcitabine Sensitivity is Improved in Pancreatic Cancer by CYR61/CCN1‐Depletion‐Mediated Upregulation of dCK and Suppression of CTGF
Authors: Ghosh Arnab , Maity Gargi , Gupta Vijaylaxmi , Haque Inamul , Sarkar Sandipto , Das Amlan , Dhar Kakali , Bhavanasi Sneha , Gunewardena Sumedha S , Von Hoff Daniel D , Mallik Sanku , Kambhampati Suman , Banerjee Sushanta , Banerjee Snigdha 
Published: June 2021

IntroductionPancreatic ductal adenocarcinoma (PDAC) develops resistance (both extrinsic and intrinsic) by preventing chemotherapeutic agents from entering inside the cells by promoting desmoplastic reactions (DR) and metabolic malfunctions of the drugs. Resistance to gemcitabine (GEM) is associated with these responses. However, the mechanism by which these resistant pathways function in the pancreatic cancer cells remains poorly understood.ObjectiveIn this study, we have shown that CYR61/CCN1‐signaling plays a vital role in making pancreatic cancer cells resistant to GEM in vitro and in‐vivo (tumor xenograft model).ResultWe have shown that the catastrophic effect of GEM could significantly be increased in GEM‐resistant PDAC cells when CYR61/CCN1 is depleted, while this effect can be suppressed in GEM‐sensitive neoplastic cells by treating them with CYR61/CCN1 recombinant protein. On the other hand, non‐transformed pancreatic cells, which are sensitive to GEM, cannot be resistant to GEM by CYR61/CCN1 protein treatment, showing a unique feature of CYR61/CCN‐signaling that only influences PDAC cells to become resistant. Additionally, we demonstrated that CYR61/CCN1 suppresses the expression of the GEM‐activating enzyme dCK while it induces the expression of a DR‐promoting factor CTGF (connective tissue growth factor) in pancreatic cancer cells in vitro and in vivo.ConclusiondCK and CTGF pathway mediated mechanisms for GEM resistance may act as a novel target for CYR61/CCN1, that protect pancreatic cancer cells from GEM. Collectively, these studies reveal a novel paradigm in which CYR61/CCN1 regulates both extrinsic and intrinsic GEM‐resistance in PDAC cells by employing unique signaling pathways.Support or Funding InformationThe work is supported by Merit review grant from Department of Veterans Affairs (Sushanta K. Banerjee, 5I01BX001989‐04 and Snigdha Banerjee, I01BX001002‐05).This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Enteropathogenic E. coli Hijacks Programmed Host‐Cell Death Pathways by Interfering with the Higher Order Oligomerization of Immune System Proteins
Authors: Monserrat‐Martinez Ana , Redpath Gregory , Govendir Matt Alfred , O'Carroll Ailis , de Andrés Murillo Andrea , Sierecki Emma , Gambin Yann 
Published: June 2021

During an infection, pathogens operate by hijacking or promoting crucial intracellular pathways within their hosts. In the case of Enteropathogenic Escherichia coli (EPEC) infection, bacterial proteins interact with host proteins to alter programmed cell death pathways. Recently, it has been found that many proteins from the immune system polymerise to transduce these death signals, forming higher order assembly structures.The aim of this project is to study how EPEC effector proteins interfere with the higher order assembly of immune proteins involved in signal transduction in inflammation, apoptosis and cell survival pathways.A selection of immune system proteins involved in signal transduction in different cell pathways was chosen to perform an in vitro screen against EPEC effector proteins by confocal spectroscopy. It was observed that espF (a bacterial effector protein) was able to change TRAF2 oligomerization/aggregation propensity. TRAF2 is a cytosolic protein involved in signal transduction in the cell death pathway. In cases of infection or stress, the protein forms higher order assembly structures to transduce the signal downstream. Further experiments performed in HeLa cells transfected with TRAF2 showed an increase in these structures in stressed cells when compared with the control group. When espF and TRAF2 were co‐transfected, co‐localization of both proteins was observed in distinct punctate intracellular structures reminiscent of higher order assemblies, together with other changes that are still under investigation.The bacterial protein espF appears to be hijacking the cell death pathway when there is an EPEC infection by avoiding TRAF2 self‐aggregation. Understanding precisely this host‐pathogen interaction could give us information useful for future drug development against EPEC infection.Support or Funding InformationEMBL Australia, University International Postgraduate Award (UIPA), University of New South WalesThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Dissecting the mechanism of host shutoff by SARS coronavirus
Authors: Nag Anita , Gomez Garret G. 
Published: June 2021

Down regulation of host gene expression during viral infection, known as host shutoff, involves destabilization of host mRNA. Several viruses, including Kaposi's sarcoma virus, Epstein B virus, severe acute respiratory syndrome coronavirus (SARS CoV) and Middle Eastern respiratory syndrome coronavirus inhibit host gene expression by stalling the ribosome on mRNA and subsequently cleaving and degrading host mRNA. In SARS‐CoV, nsp1 is the key factor in virus‐induced down‐regulation of host gene expression. In infected cells, nsp1 engages in a multi‐pronged mechanism to inhibit host gene expression by binding to the 40S ribosomal subunit to stall further ribosome assembly and inducing endonucleolytic cleavage and degradation of host mRNAs. We identified a previously undetected mechanism by which nsp1 exploits the nuclear pore complex and disrupts nuclear‐cytoplasmic transport of biomolecules. Using quantitative proteomics we identified members of the nuclear pore complex from nsp1‐associated protein assembly. Expression of nsp1 in HEK cells disrupts Nup93 localization around the nuclear envelope without triggering proteolytic degradation of the protein while other nucleoporins and the nuclear lamina remain unperturbed, suggesting significant alteration of the nuclear pore complex in the presence of nsp1. Furthermore, Nup93 reconvenes to the nuclear pore when nsp1 is removed. Consistent with its role in host shutoff, nsp1 alters the nuclear‐cytoplasmic distribution of a RNA binding protein, nucleolin. Our results suggest that nsp1 alone can regulate multiple steps of gene expression including nuclear‐cytoplasmic transport.Support or Funding InformationSC INBRE Bioinformatics Pilot Project AwardSCICUThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Translational Fusion of a G‐protein Coupled‐Receptor from the Hookworm Ancylostoma ceylanicum Expressed in Caenorhabditis elegans
Authors: Norman Brandon , DeLong Lauren , Dickey Myra , Jewell Mollie , Erickson Patti T. , Ratnappan Ramesh , O'Halloran Damien , Hawdon John M. 
Published: June 2021

Hookworms are infectious parasites that affect more than 500 million people worldwide, causing extensive morbidity and economic burden in developing countries. Mass drug administration is a current control method, but resistance is of concern. Many hookworm species, including those in the genus Ancylostoma, are specialists and require specific host signals to continue development upon infection. Little is known about the signaling mechanisms, although evolutionary conservation between parasitic nematodes and the model organism C. elegans suggests that G‐protein coupled receptors (GPCRs) expressed in amphid neurons are chemosensory detection candidates. The amphid neurons of C. elegans are exposed to the environment, even during the dauer stage, an alternate phase of larval development that is similar to the parasitic infective juvenile stage. Previous experiments involving A. ceylanicum transcriptional GFP fusions in C. elegans identified putative GPCR genes expressed in neurons during dauer stage. To confirm that hookworm proteins are neuronally localized under dauer conditions, a translational GFP fusion of a putative hookworm GPCR was generated. The entire coding sequence, plus introns, was cloned using homologous recombination‐based, yeast assembly methods to create a C‐terminal GFP fusion. The putative A. ceylanicum promoter consisted of the upstream intergenic region, which is approximately 5000 base pairs, and the transcriptional terminator from C. elegans unc‐54 was used. To generate the expression plasmid, amplicons containing homology to the adjacent segment in the assembly were amplified using polymerase chain reaction (PCR) and transformed into yeast. The plasmid was verified by junction‐confirming PCR analysis, restriction enzyme mapping, and sequencing. After microinjection, GFP expression in amphid neurons of stably transformed C. elegans during the dauer stage would support the hypothesis that this putative GPCR plays a role in reception of host signaling molecules and may provide a possible therapeutic target.Support or Funding InformationThis work was supported by the Salisbury University Faculty Mini‐Grant Program.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Determination of Antimicrobial Activity and Secondary Metabolites in Acacia rigidula and Acacia berlandieri
Authors: Gonzalez David Israel 
Published: June 2021

There is continuous interest in the antimicrobial activities of different extracts obtained from plants especially traditional medicinal plants. There are more than 20,000 species of plants used in traditional medicines. Therapeutic drugs can be derived from natural products, which are usually secondary metabolites and their derivatives. Drugs derived from these secondary metabolites can be used to fight against the increased presence of antibiotic‐resistant bacteria. Therefore, finding new antimicrobial agents is important for the continuing development of new therapeutic drugs. In this study, plants found in South Texas have been a focus of interest in terms of antimicrobial activity present in their secondary metabolites. Studies have indicated that Acacia species, such as Acacia nilotica, have displayed antimicrobial activity. The objectives of this study were to determine the presence of antimicrobial activities and qualitatively determine the secondary metabolites of plant extracts from Acacia rigidula (Blackbrush) and Acacia berlandieri (Guajillo). The extracts were subjected to acetone, methanol, acetic acid to extract secondary metabolites. To test the antimicrobial activities of the species, the disk diffusion method was employed against gram‐positive and gram‐negative bacteria such as: Escherichia coli, Staphylococcus aureus, Serratia marcescens, Enterococcus faecalis, and Enterobacter aerogenes. Qualitative determinations of the presence of phenols, tannins, terpenoids, alkaloids, and flavonoids were done. Thus, this study will report the antimicrobial activities of A. rigidula and A. berlandieri extracts. Preliminary results of the disk diffusion method indicate the presence of antimicrobial activity against E. coli found in the bark of A. rigidula extracted with acetic acid and the leaves of A. berlandieri extracted with acetone. The zone of inhibition measured was 14.9 mm and 15.1 mm respectively. To compare with a positive control, streptomycin displayed a zone of inhibition of 16.5 mm against the E. Coli confirming the antimicrobial activity from the two species. Future results will establish the antimicrobial activity further once tested against different bacteria. This study will also report the secondary metabolites present in the extracts understudy. The findings of this study will provide researchers with the basis to derive potential medications against antibiotic‐resistant bacteria.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Generation of a Difluoromethylornithine (DFMO) Resistant Cell Line in a Polyamine Depletion Strategy
Authors: Noureddine Sarah , Dobrovolskaite Aiste , Phanstiel Otto , von Kalm Laurence 
Published: June 2021

Polyamines are essential growth factors for normal and malignant cells. Cells obtain polyamines via biosynthesis or transport from the extracellular environment and polyamine depletion therapy is an attractive option to inhibit the growth of cancer cells. Previous reports have indicated that depletion therapy (e.g. androgen depletion in prostate cancer) can lead to epigenetic changes resulting in resistance to the therapy and aggressive metastatic cancer. We were interested to know if polyamine depletion driven by treatment with the polyamine biosynthesis inhibitor difluoromethylornithine (DFMO) could lead to similar outcomes. The pancreatic cancer cell line Panc‐1 was passaged for 10 generations on IC50 and IC75 concentrations of DFMO, after which a decreased sensitivity to DFMO was observed. Our results indicate the need for further investigation into the mechanism of resistance to DFMO, and it's potential consequences for clinical outcomes.Support or Funding InformationUniversity of Central Florida, College of Sciences Seed AwardThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Docosahexaenoic acid (DHA) as an adjunctive therapeutic agent for the treatment of cancer
Authors: Rahman Mizanur , Ouhtit Allal , Saleh Haissam Abou 
Published: June 2021

Breast and prostate cancers are the leading causes of cancer‐related death among women and men respectively. A significant challenge in treating these cancers is the limited array of therapeutic options and the rapid development of resistance to existing agents as well as severe side effects associated with these agents. Thus, finding new natural compounds would of great interest to improve the effectiveness of current agents, decrease the emergence of resistance, and increase side effects‐free survival. To this end, docosahexaenoic acid (DHA), a marine derived non toxic natural lipid (approved by FDA as generally recognized as safe (GRAS)), has been shown to enhance the cytotoxicity of various anticancer drugs to a variety of cancer cell lines or tumors in animal models. We first demonstrated if DHA can enhance the breast cancer cell killing by doxorubicin (Dox) using human breast adenocarcinoma cell line. Interestingly, DHA augmented the Dox induced inhibition of breast cancer cell proliferation, and invasion and Dox induced stimulation of cell cycle arrest at G2/M phase and apoptosis. Moreover, DHA boosted the chemosensitization of doxorubicin‐resistant human breast adenocarcinoma to doxorubicin. This improved chemosensitization was accompanied with enhanced accumulation of doxorubicin, reduction of P‐glycoprotein (P‐gp)‐ a classical multi drug resistance (MDR) transporter, and TG2‐ a tumor survival factor under stress condition, and induction of lipid peroxidation, and pro‐apoptotic markers Bak1 and caspase 3 in drug resistant breast cancer cell. In a separate study, we also determined if DHA can augment the anticancer effect of an FDA approved histone deacetylase inhibitor, valproic acid (VPA). Several phase 1 and 2 clinical trials demonstrated that VPA delayed the prostate cancer recurrence but exhibiting severe side effects at its effective dose. Using in vitro cell culture model, we demonstrated that VPA dose could be reduced down to half when combined with DHA to achieve same level of prostate cancer cell killing as seen with VPA alone at high dose. Our findings demonstrated that DHA might be a promising natural adjunctive therapeutic natural compound to improve the efficacy of existing cancer drugs and to reduce the toxic side effects associated with these drugs. Further preclinical, clinical, and mechanistic studies are required to establish the DHA as an adjunctive natural therapy to augment the efficacy of existing cancer drugs.Support or Funding InformationQatar University grant QUUG‐CAS‐DBES‐15/16‐23This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Fatty Acid‐Induced Hepatocellular Carcinoma Growth is Mediated by Decreasing Mitochondrial H2O2 Emission Coupled to Increased Glutathione Levels
Authors: Turnbull Patrick C. , Dehghani Ali C. , Perry Christopher G. R. 
Published: June 2021

Rationale and HypothesisHigh fat diets are associated with increased hepatocellular carcinoma (HCC) risk, as well as increased HCC growth rates. Accelerated HCC growth in response to fatty acid challenges has been attributed to a variety of signalling pathways, but the role of metabolic and redox flexibility in mediating a pro‐growth environment in this context has not been examined. Here we examined the direct effect of fatty acid challenges on HCC growth in relation to altered metabolic and redox homeostasis.Experimental approachThe HCC cell line HepG2 was incubated with 0μM, 50μM and 100μM palmitoylcarnitine (PCarn) for up to 48 hrs. We measured clonogenic survival, mitochondrial H2O2 emission and glutathione following PCarn incubations with and without the glutathione depleting agent buthionine sulfoximine (BSO) and inhibition of uncoupling protein‐2 (UCP2) activity by genipin.Results100μM PCarn increased clonogenic survival in HepG2 by 8% more than control (p<0.05) at 48 hrs which represents a marked early effect considering the population doubling time of HepG2 cells is ~48 hrs. This was associated with an increase in both reduced and oxidized glutathione at both 24 and 48 hrs (p<0.05). Depleting glutathione with BSO prevented PCarn‐stimulated growth (p<0.05). In a separate experiment, acute incubations of 100μM PCarn increased H2O2 emission within the first 10 minutes (p<0.05) followed by a decrease in H2O2 at 1 hr that remained lower at 24 hrs (p<0.05). The acute increase in H2O2 followed by a more chronic depression in H2O2 suggested PCarn might have triggered a compensatory mechanism. In support of this notion, inhibition of UCP2 with genipin sensitized HepG2 cells to PCarn‐induced decreases in clonogenic survival (p<0.05) without a change in UCP2 protein content.ConclusionCollectively, this data suggests that PCarn‐induced HCC growth is in part attributed to elevated glutathione. Increases in glutathione may be a result of UCP2 rapidly attenuating PCarn‐induced H2O2 emission which may permit greater glutathione synthetic rates and creation of a pro‐growth redox environment.Support or Funding InformationFunding was provided to C.G.R.P. by National Science and Engineering Research Council (#436138‐2013) with infrastructure supported by Canada Foundation for Innovation, Ontario Research Fund and the James H. Cummings Foundation. P. C. T. was supported by an NSERC CGS‐D scholarship.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Inflammatory and Nutritional Biomarkers in the Plasma of Women in Zambia Reflect Low DHA and HIV Status
Authors: Kisling Sophia , Majid Sonoor , Wood Charles , Chunda Catherine , DiRusso Concetta 
Published: June 2021

Docosahexanenoic Acid (DHA) is a fatty acid that is abundant in the brain, retina, and cerebral cortex. It is critical in fetal brain development and is implicated in resolution of inflammation. In recent years, there has been a growing concern that low dietary levels of DHA in pregnancy may lead to poor birth outcomes and delayed or reduced cognitive function in children after birth. Uncontrolled HIV infection may lead to cognitive impairments as well as reduced immune function. Therefore, for pregnant women living with food insecurity and HIV infection, these problems may be compounded and health risks to their infants high. To evaluate these concerns, a pre‐clinical trial was conducted in pregnant women in Zambia, a country where malnutrition and HIV are endemic. The study participants included 91 women in the second trimester of pregnancy, 46 of which were HIV seropositive and 45 HIV seronegative. Among the HIV positive participants 11 had high viral load. The overarching study goal was to determine if plasma DHA levels were low relative to global averages and if they correlated with inflammation and HIV status. Hematological assessment included measurement of biomarkers for nutritional status, HIV status and viral load, as well as inflammation. Plasma lipids were assessed using the Folch extraction method, fatty acid methyl esters were prepared and analyzed by gas chromatography/mass spectrometry. Protein biomarkers data were measured using commercial ELISA kits. Overall, DHA levels were low at 2.16±0.75 mass percent of total fatty acids but did not vary significantly with HIV status. Averages of the nutritional biomarkers insulin and leptin were low and high, respectively, compared to global averages when comparing all participants. Insulin was not significantly different based on HIV status. Leptin was reduced in HIV seropositive participants compared to those who were seronegative and this correlated, as expected, with pre‐pregnancy BMI. For the inflammatory markers CRP and LCN2, only LCN2 was significantly different dependent on HIV status, and levels were on average lower in seropositive individuals. Within the HIV positive participants, the 11 with high vial load did not have levels of insulin, leptin, CRP or LCN2 that were significantly different from those with low viral load. These data demonstrate that select protein biomarkers for inflammation and nutrition are variably affected by HIV and nutritional status. Currently, these studies are being expanded to understand the role of dietary fatty acids in contributing to health outcomes in pregnancy and dependent upon HIV status.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.