bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of tobacco‐specific nitrosamine (TSNA) content in smokeless tobacco products in Bangladesh
Authors: Nasrin Shamema , Chen Gang , Watson Christy J , Lazarus Philip 
Published: June 2021

Head and neck cancers are among the most common cancers in Southeast Asia and are likely to face sharp increases in the coming years due to the widespread use of smokeless tobacco (SLT) products. Bangladesh has the second highest oral cancer mortality rate as well as the second highest rate of SLT product usage worldwide. SLT products contain high levels of the highly carcinogenic tobacco‐specific nitrosamines (TSNAs); they include N‐nitrosonornicotine (NNN), 4‐(methylnitrosamino)‐1‐(3‐pyridyl)‐1‐butanone (NNK), N‐nitrosoanatabine (NAT), and N‐nitrosoanabasine (NAB). To date, the amount of TSNAs present in Bangladeshi SLT products has not been reported. The goal of the present study was to develop an efficient TSNA and nicotine extraction method to quantify the levels of TSNAs and nicotine present in 31 Bangladeshi SLT products. The concentration of NNN, NNK, NAT, and NAB in Bangladeshi SLT brands ranged from 1.07–59.18 μg/g SLT, 0.15–33.70 μg/g SLT, 0.79–44.64 μg/g SLT, and 0.03–12.85 μg/g SLT, respectively. Pan Masala, which is labeled as a non‐tobacco product, also contains low levels of TSNAs. Betel nut, a common flavor additive in SLT products in Bangladesh, contained no detectible TSNA levels. Bangladeshi SLT products contained significantly higher (p<0.05) levels of TSNAs as compared to SLT brands from the United States (U.S.), and were higher on average than the levels observed in brands in other regions of southern Asia. NNN and NNK levels were 16 and 19, 2 and 3.5, and 62 and 85 fold higher than U.S., Indian and Pakistani SLT brands, respectively. Additionally, the levels of NNN and NNK measured in U.S. brands in this study were 1.2‐fold higher than previously reported values from 2013. This study demonstrates that the levels of TSNAs, including the major tobacco carcinogens NNN and NNK, are far higher in Bangladeshi SLT brands than they are in other regions of the world. Exposure to such high levels of carcinogens may be the most important contributing factor to the rate of head and neck as well as other tobacco‐related cancers observed in Bangladesh.Support or Funding InformationThis work is supported in part by grants from NIH, National Cancer Institute (grant R01‐ES025460, to P. Lazarus) and the Health Sciences and Services Authority of Spokane, Washington (grant WSU002292, to College of Pharmacy and Pharmaceutical Sciences, Washington State University)This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Oxidative Stability and Antiproliferative Effect of Fish Oil Commercial Supplements on Cultured Human Keratinocytes
Authors: de Oliveira Carvalho Patricia , de Santis Gabrielle Kristine Doratiotto , Franco Yollanda Edwirges Moreira , Barba Fatima Cristine Ribeiro , de Souza dos Santos Gisele Karine , Longato Giovanna Barbarini 
Published: June 2021

Fish oil, due high concentration of n‐3 polyunsaturated fatty acids (n‐3 PUFA), reduce symptoms in many inflammatory skin diseases, limiting the spreading of the inflammatory process. Oxidized derivative was shown to play an important role in the antiproliferative properties of n‐3 PUFA. The objective of this study was to assess the PUFA content, oxidative stability and antiproliferative effects on cultured human keratinocytes of fish oil commercial supplements. Lipid oxidation was measured by colorimetric reactions and the fatty acid composition was measured using gas chromatography. Primary (peroxide), secondary (anisidine), and total oxidation products levels of two supplements exceeded maximum established by international standards of quality. In vitro inhibitory activity against HaCat cell lines, measured with the tetrazolium MTT (3‐(4,5‐dimethylthiazolyl‐2)‐2,5‐diphenyltetrazolium bromide) assay, showed that the supplement of higher oxidation content exerted the most potent antiproliferative effect (IG50 86.54 μg/mL). Our data provide additional information regarding the preferential antiproliferative effect of oxidized derivatives of n‐3 PUFA in cultured human keratinocytesSupport or Funding InformationFAPESP and CAPES (Finance Code 001)This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Functional Characterization of Novel CYP2C9 Variants Found in an Alaska Native Population
Authors: Henderson Lindsay M , McDonald Matthew G , Rettie Allan E , Thummel Kenneth E 
Published: June 2021

Coding‐region variants of CYP2C9 can dramatically influence the pharmacokinetics and drug response of therapeutic agents, an important clinical consideration for commonly used CYP2C9 narrow therapeutic index substrates, including (S)‐warfarin and phenytoin. In the Yup'ik Alaska Native people, novel CYP2C9 protein variants M1L, N218I, and P279T are expressed with higher frequencies than the well‐characterized CYP2C9*2 and CYP2C9*3 alleles. This study's objective was to determine the relative expression of these CYP2C9 variants in HepG2 cells and to characterize the function of the purified reconstituted enzymes expressed in E. coli, towards several CYP2C9 drug substrates.While mRNA expression of the CYP2C9 M1L, N218I, and P279T gene variants and the reference (wildtype) protein in HepG2 cells were similar, the protein was undetectable for the M1L variant. This is expected, due to disruption of the start codon in CYP2C9 M1L. His‐tagged CYP2C9 reference protein and N218I and P279T variants expressed well in E. coli and were highly purified after affinity chromatography. Following reconstitution with cytochrome P450 reductase and cytochrome b5, the N218I and P279T variants metabolized (S)‐warfarin, but not (R)‐warfarin, to the principal 7‐ and 6‐hydroxy metabolites formed by the reference enzyme. Kinetic studies of (S)‐warfarin metabolism demonstrate that the N218I variant has reduced function, with less than 40% of the catalytic efficiency of reference enzyme, while the P279T variant had similar catalytic efficiency to that of reference CYP2C9. Similar, although not identical concentration–rate profiles were obtained for phenytoin, flurbiprofen and naproxen metabolism.The potential of CYP2C9 M1L, N218I, and perhaps even P279T alleles to alter the pharmacokinetics of drugs metabolized by CYP2C9 may put carriers at risk of exacerbated therapeutic effects from drugs that rely predominantly on CYP2C9 for their metabolic clearance. Further clinical implications for the Alaska Native people include phenotypic misclassification from currently available pharmacogenetic tests, which typically screen only for the common CYP2C9*2 (R144C) and CYP2C9*3 (I359T) variants.Support or Funding InformationP01 GM116691, T32 GM 007750This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Nanoparticle‐Mediated Inhibition of Acute Leukemic Stem Cells
Authors: Glass Sterling , Gonzalez‐Fajardo Laura , Lu Xiuling 
Published: June 2021

Chemoresistance accounts for 90% of failed chemotherapeutic treatments. Chemoresistant cancer stem cells (CSC) contribute to these poor outcomes via self‐renewal and non‐tumorigenic differentiation. While CSC subpopulations have been shown to contribute to cancer advancement and recurrence, targeting them has proven difficult. Doxorubicin (DOX) is a potent chemotherapeutic agent used to treat many types of solid and hematologic cancers, including leukemia. Leukemic stem cells (LSC) are associated with chemoresistance, tumor relapse, and poor patient survival. DOX exhibits broad cytotoxicity but is accompanied by severe and sometimes life‐threatening toxicities. We have developed DOX‐loaded polymeric nanoparticles (DOX‐NP) to overcome these problems. These novel, patented nanoparticle delivery systems can diminish adverse effects of DOX administration, such as cardiac toxicity, via improved biodistribution and preferential accumulation in cancer sites. Nanoparticle‐mediated delivery of DOX shows promise as a potential treatment to specifically target LSC. Previous findings from a collaborative effort revealed the ability of low‐dose DOX to specifically inhibit pS552‐β‐catenin, a key mediator of LSC self‐renewal in T‐cell acute lymphocytic leukemia (T‐ALL). Our DOX‐NPs exhibited long circulation times and improved cardiac toxicity compared to free DOX. In vivo, our DOX‐NPs successfully inhibited LSC and promoted normal HSPC recovery with 3‐fold greater median survival than Doxil® (FDA‐approved liposomal DOX) in a patient‐derived xenograft (PDX) model of T‐ALL. In contrast, Doxil® promoted LSC expansion. To identify the mechanisms underlying the DOX‐NP treatment advantages, DOX‐NPs were compared with Doxil® based on in vitro DOX release, cytotoxicity to leukemic cells and bone marrow cells, and in vivo bone marrow accumulation. The DOX‐NPs exhibited slower drug release than Doxil®, which may allow for longer exposure of DOX to LSC. Significant bone marrow accumulation has been observed in both nanoparticle systems. Further understanding of the contribution of DOX accumulation in bone marrow to LSC inhibition in addition to determining the cytotoxicity of both DOX formulations to LSC and leukemic cells will aid in designing an effective drug‐loaded nanotherapeutic to target pS552‐β‐catenin for inhibiting LSC self‐renewal.Support or Funding InformationThis work was supported by the UCONN Academic Plan Grant, the Promising Project Award from the Program in Innovation Therapeutics for Connecticut's Health (PITCH), and the UCONN START PPOC grant.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Venetoclax, a Novel BCL‐2 Inhibitor, Induces Cell Growth Suppression, Apoptosis, Cell Cycle Arrest, and Autophagy in Triple Negative Breast Cancer MDA‐MB‐231 Cells
Authors: Korashy Hesham M. , Alatwi Fahad O. , Alhoshani Ali , El Gamal Heba M. , Shamoon Licia S. , Ghanim Sarah S. , Agouni Abdelali 
Published: June 2021

Venetoclax (VCX), formally known as ABT‐199, is a selective and orally bioavailable small‐molecule B‐cell lymphoma 2 (BCL‐2) Homology 3 (BH3) mimetic, with potential pro‐apoptotic and antineoplastic activities. In April 2016, VCX was approved in the USA to treat patients with chronic lymphocytic leukemia (CLL) with chromosome 17p deletion who have received at least one prior treatment. VCX inhibits the activity of a novel target, Bcl‐2 protein, liberating the BH3‐only proteins and thus restoring apoptotic processes in tumor cells, via activation of BAK/BAX‐mediated apoptosis. The BCL‐2 protein is commonly expressed in several of human cancer including solid tumors, such as breast cancer, ovarian, lung, colorectal, stomach, and prostate cancers, as its expression has been shown to be associated with an aggressive disease course and poor survival. Although, BCL‐2 is expressed in several sub‐types of breast cancer, neither VCX nor any other BCL‐2 inhibitor agents alone or in combination with other chemotherapeutic agents have been tested against triple negative breast cancer (TNBC). Accordingly, we hypothesized that VCX is able to induce TNBC cell growth inhibition via induction of apoptosis, autophagy, and cell cycle arrest. To test this hypothesis, human TNBC MDA‐MB‐231 cells were treated for indicated intervals with increasing concentrations of VCX, thereafter, the effects of VCX on cell proliferation and cell cycle arrest were determined using flow cytometry. Furthermore, the apoptogenic effect of VCX was explored by measuring the percentage of apoptotic cells using flow cytometry and the expression of caspases, BAX, and BCl2 genes at the mRNA, protein, and activity levels. The results of the present study showed that VCX decreased the growth and proliferation of TNBC MDA‐MB‐231 cells in a concentration manner. This growth suppression was associated with a significant increase in the percentage of apoptotic MDA‐MB‐231 cells with a significant increase in the expression of several apoptotic genes, caspase3, caspase7, and BAX in concentration‐dependent manner. Importantly, the VCX‐induced‐apoptosis was accompanied with cell cycle arrest at G0/G1 phase with a concentration‐dependent inhibition of cell cycle proliferator genes, such as Cyclin D1 and E2F1. In addition, VCX treatment induced a significant increase in the level of autophagy marker LC3‐II mRNA and protein expression levels. In conclusion, the present study demonstrates the first evidence that VCX induces human TNBC MDA‐MB‐231 cell growth inhibition through the induction of apoptosis, cell cycle arrest, and autophagy mechanisms.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Evaluation of Sensitivity of Two Triple Negative Breast Cancer Cell Lines to 2, 3‐ dichloro‐5, 8‐dimethoxy‐1, 4‐naphthoquinone and 4 Hydroxy‐Tamoxifen
Authors: Robinson Anastasia G.J. , Copeland Robert Leon 
Published: June 2021

Breast cancer (BC) is a heterogeneous disease and it is one of the leading causes of mortality worldwide in women each year. However, in the United States, there is a disparity in survival between African American (AA) and Caucasian women with AA women having a higher rate of mortality. BC is typically classified based on the expression of the following receptors: Estrogen receptor α (ERα), Progesterone receptor (PR) and Human Epidermal Growth Factor Receptor 2 (HER2). Conventional treatment for BC relies on the expression of ERα for anti‐estrogenic therapy and HER2 for HER2 inhibition. Triple negative breast cancer (TNBC) is a form of breast cancer which lacks expression of ERα, PR and HER2 and affects minority population disproportionately. Potential mechanisms for the loss of ERα expression include hyperactivation of MAPK pathways due to EGFR or HER2 overexpression, estrogen withdrawal, hypoxia and methylation of the CpG island, cytosine‐guanine abundant area, on the ER gene promoter region. Due to lack of targetted treatment for TNBC, alternative treatment options are essential to increase patient survivability. 2, 3‐ dichloro‐5, 8‐dimethoxy‐1, 4‐naphthoquinone (Z285), a 1,4 napthoquinone analog, has demonstrated cytotoxic effects in estrogen positive and estrogen negative cell lines. Previous in silico data showed that this compound may function as an MAPK allosteric inhibitor. MCF7 cells were used as an ERα positive control and two TNBC cell lines, HCC1806, from a AA woman, and MDA MB 231, from a Caucasian woman, were used. Cell viability studies were carried out on cells treated with Z285 alone (0.5–10μM), 4 Hydroxy‐Tamoxifen (4OH‐Tam) alone (3–30μM) for 24,72 and 120hrs. In combination studies, the cells were pretreated with Z285 (2 or 5μM) for 6 hrs followed by 4OH‐Tam (1–15μM) for 24, 72 and 120hrs. These results showed a dose and time‐dependent response with individual treatment. Combinatory studies showed significant decreases in cell viability when compared to individual studies. Cells were treated with 5 μM Z285 and mRNA was collected for RNA microarray analysis to determine changes in mRNA expression profile. These results showed modulation of several genes involved in the MAPK pathway and suggest a mechanism of increased sensitivity of the TNBC cells to 4OH‐Tamoxifen. Therefore, this novel compound which targets the MAPK pathway may offer a model for treating TNBC breast cancers by reactivating ERα expression in these cancers and thus rendering them susceptible to anti‐estrogen therapy.Support or Funding InformationCharles and Mary Latham FundThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Targeted Osmotic Lysis of H28 Mesothelioma Cells
Authors: Edenfield Samantha , Sherman Kelly Jean , Scahill Steven D. , Gould Harry J. , Paul Dennis 
Published: June 2021

Mesothelioma is an aggressive cancer of the pleura cells of the chest cavity commonly linked to asbestos exposure. With a post‐diagnosis prognosis of between 6 and 12 months. Traditional chemotherapy increases survival time by only 11 weeks. Targeted Osmotic Lysis (TOL) is a novel cancer therapeutic that exploits cancer cells' upregulation of Voltage‐Gated Sodium Channels (VGSC) by pairing a pharmacological blocker of Na+, K+‐ATPase (sodium pumps), such as digoxin or ouabain, with electric or magnetic stimulation of VGSCs. The increase in intracellular Na+ causes an osmotic lysis of cells that over‐express VGSCs. TOL has been shown to selectively lyse highly invasive breast cancer cells, such as MDA‐MB 231, while leaving the normal tissue intact. To test the hypothesis that TOL would be an effective treatment for mesothelioma, we incubated H28 mesothelioma cells or MeT‐5A normal pleural effusion cells in 0–500 nM digoxin for 10 min, then activated the VGSCs with a 0–5 VDC electric current for 30 min. Using video microscopy, lysis was assessed by two independent observers with cytosolic extrusion as the measure. TOL effectively lysed H28 cells dose‐ and stimulus‐dependently, with a maximum cell death of 94.2% Less than 5% of cells in the Drug only, Stimulation only, and Non‐treated groups died (p<.0001). MeT‐5A cells did not lyse. Likewise, when we used a pulsed magnetic field (90 mT, 25 pps) to stimulate VGSCs, H28 cells lysed dose‐ and stimulation‐dependently, whereas control treatments and Met‐5a cells did not. Together these results are evidence that TOL causes significant cell death in mesothelioma cells compared to the normal cells. Thus, TOL may be an effective treatment for mesothelioma.Support or Funding InformationThis research was supported by a grant from Oleander Medical TechnologiesThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Differential Impact of RGS6 on GIRK‐dependent Muscarinic and Adenosine Receptor Signaling in Mouse Sinoatrial Nodal Cells
Authors: Anderson Allison , Wickman Kevin 
Published: June 2021

IntroductionParasympathetic slowing of heart rate is largely mediated by muscarinic receptor (M2R) activation of the G protein gated inwardly‐rectifying potassium (GIRK) channel on sinoatrial nodal (SAN) cells and atrial myocytes. The strength of M2R‐GIRK signaling is negatively regulated by regulator of G protein signaling 6, RGS6. Genetic ablation of RGS6 in mice gives rise to enhanced M2R‐GIRK signaling in SAN cells, resulting in both exaggerated M2R‐induced bradycardia and increased susceptibility to pacing‐induced atrial fibrillation. Adenosine, used clinically to both diagnose and treat certain arrhythmias, exerts these actions through adenosine receptor (A1R) activation of cardiac GIRK channels. The extent to which RGS6 regulates A1R‐GIRK signaling, however, is not understood. Here, we investigated and compared the impact of RGS6 on A1R‐GIRK and M2R‐GIRK signaling in mouse SAN cells and heart rate.Methods and ResultsUsing whole‐cell patch‐clamp electrophysiology, we measured the efficacy and potency of M2R‐ and A1R‐GIRK channel signaling in adult SAN cells from wildtype and Rgs6−/− mice. SAN cells from Rgs6−/− mice displayed both prolonged channel deactivation kinetics and increased channel sensitivity to CCh‐induced currents as compared to wild‐type SAN cells. Surprisingly, we found no difference in kinetics or channel sensitivity of A1R‐GIRK responses in Rgs6−/− SAN cells. We did observe a striking, significant increase in the amplitude of the A1R‐GIRK response in Rgs6−/− SAN cells compared to wild‐type controls. Recordings from mice lacking cardiac GIRK channels (Girk4−/−) confirm that M2R‐ and A1R‐induced currents are GIRK‐dependent. Furthermore, occlusion studies in wild‐type SAN cells suggest that M2R activates nearly all of the GIRK channels present in SAN cells, while A1R activates a smaller portion of GIRK channels. Intriguingly, RGS6 ablation seems to allow for the activation of a larger proportion of GIRK channels by A1R. Heart rate measurements from isolated Rgs6−/− hearts show exaggerated bradycardia in response to the same doses of CPA, an A1R agonist, as compared to wild‐type controls. Significantly lower heart rates were observed in response to lower doses of CCh in isolated Rgs6−/− hearts as compared to wild‐type hearts, suggesting a shift in sensitivity.ConclusionsOur results suggest that A1R‐GIRK channel signaling displays distinct differences from M2R‐GIRK channel signaling, resulting in distinct negative regulation by RGS6 in mouse SAN cells and the isolated heart.Support or Funding InformationThis work was supported by NIH grants KW (HL105550) and AA (HL139090).This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
GRK5‐mediated Exacerbation of Ischemic Heart Failure Involves Cardiac Immune and Inflammatory Responses
Authors: de Lucia Claudio , Grisanti Laurel A. , Borghetti Giulia , Ibetti Jessica , Lucchese Anna Maria , Gao Erhe , Rengo Giuseppe , Houser Steven R. , Tilley Douglas , Koch Walter J. 
Published: June 2021

RATIONALECoronary artery disease and subsequent myocardial ischemia (MI) are the most common cause of heart failure (HF) in the US. G protein‐coupled receptor (GPCR) kinase 5 (GRK5) has been shown to be upregulated in failing human myocardium. While the canonical role of GRKs is to desensitize receptors via phosphorylation, GRK5 can also locate to the nucleus of cardiomyocytes where it exerts GPCR‐independent effects that promote maladaptive cardiac hypertrophy after hypertrophic stress. Despite numerous data indicating the importance of GRK5 in hypertrophy, it is still unknown if GRK5 has a role in ischemic heart disease.OBJECTIVEIn this study, we investigated the critical role that GRK5 plays after myocardial ischemic injury with a novel aspect being the regulation of immune and inflammatory responses including recruitment of immune cells to the injured heart.METHODS AND RESULTSCardiac‐specific GRK5 transgenic mice (Tg‐GRK5) and non‐transgenic littermate (NLC) control mice were subjected to MI. Tg‐GRK5‐HF mice showed decreased cardiac function (both global and segmental contractility), augmented left ventricular diameters/volumes and decreased survival rate compared to NLC‐HF mice. Heart weight (HW) to body weight or to tibia length ratios as well as mRNA expression of all major adverse remodeling‐associated biomarkers (ANF, BNP, b‐MHC) were increased in the TgGRK5‐HF compared to NLC‐HF. Cardiac fibrosis in the border zone (BZ) area as well as mRNA levels of Collagen‐1 (Col‐1), Col‐3, MMP2 and CTGF were higher in TgGRK5‐HF compared to NLC‐HF, strongly suggesting increased adverse remodeling. Cardiac inflammatory cytokines (IL‐6 and IL‐1beta), adhesion molecule (VCAM‐1) and chemokines (CCL2, CCL3, CCL5) were augmented in TgGRK5‐HF compared to NLC‐HF and contribute at least in part to increased immune cell recruitment in the heart. In fact, we found neutrophils/macrophages and T‐lymphocytes (T‐cells) respectively augmented at 4 days and 8 weeks after MI in both BZ and infarct zone. Interestingly, cardiac‐specific GRK2 transgenic mice did not show increased cardiac inflammation and chemokine production after MI when compared to NLC‐HF mice.CONCLUSIONSOur study shows that cardiac GRK5 has a detrimental effect during ischemic HF. GRK5 overexpression causes reduced cardiac function and increased immune cell recruitment/inflammation. Further, these results suggest GRK5 as a potential therapeutic target to limit HF development after ischemic injury.Support or Funding InformationThis work was supported by National Institutes of Health (NIH P01 HL091799, NIH R37 HL061690, NIH P01 HL075443 [Project 2]) to W.J.K. and American Heart Association (postdoctoral fellowship 17POST33660942) to C.d.L..This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.