bluuebunny/crossref_metadata_2025_split huggingface dataset:
c‐Jun N‐terminal kinase 2 contributes to the tumorigenesis of non‐small cell lung carcinoma through MKK4‐dependent and MKK7‐independent mechanism
Authors: Kaoud Tamer Saad , Du Lili , Tsai Kenneth Y. , Dalby Kevin N. 
Published: November 2023

It had been reported previously that the JNKs require phosphorylation by both MKK4 and MKK7 to become activated. While the JNK2 isoform shows a unique propensity among the JNKs to autophosphorylate in vitro. Recent studies in glioblastoma and lung carcinoma have suggested important roles for constitutive activation of JNK2 (but not JNK1). Here we show that JNK2 autophosphorylation contributes to the proliferation of NSCLC cells under conditions of low serum through an MKK4‐dependent and MKK7‐independent mechanism. Using recombinant activated (MKK4 & MKK7) and inactivated (JNK1 & JNK2), we investigated the mechanism of JNK2 autophosphorylation and found that it has a strong preference to autophosphorylate on Thr‐183, while exhibiting a slower phosphorylation on Tyr‐185. This ability to efficiently autophosphorylate on Thr‐183 distinguishes it from other isoforms and facilitates its activation through a previously unknown mechanism involving MKK4. Phosphorylation of Tyr‐185 by MKK4 synergizes with Thr‐183 autophosphorylation to activate JNK2.Evidence in multiple cell lines including mouse embryonic stem cells lacking MKK4 or MKK7 suggests that autophosphorylation alone activates JNK2 weakly in cells. However, JNK2 autophosphorylates on Thr‐183, to create a pool of JNK2 primed for activation by MKK4, which phosphorylates JNK2 on Tyr‐185 to activate it. Under conditions of low serum JNK2, but not JNK1 exhibits a dose‐dependent dephosphorylation upon treatment of NSCLC cells with the pan‐JNK ATP competitive inhibitors (JNK‐IN‐8 and SP600125), further supporting the notion that active JNK2 results primarily from autophosphorylation of Thr‐183. Under similar conditions of low serum the MKK4‐JNK2 pathway but not MKK7 or JNK1 promotes proliferation of NSCLC through STAT3. This was further investigated in vivo using A549 Xenografts in which either JNK2 or MKK4 were stably knocked down. Taken together the data suggest that JNK2 autophosphorylation primes it for activation by MKK4. This pathway promotes the activation of c‐jun and the proliferation of NSCLC in vivo.Support or Funding InformationSupport by NIH (GM059802, GM106137, and CA167505), the Welch Foundation (F‐1390 and F‐1691), CPRIT (RP101501, RP140648, and RP140649)
Ablation Of Neuropilin 1 in Glioma‐Associated Macrophages Slows Tumor Progression
Authors: Miyauchi Jeremy Tetsuo , Chen Danling , Nissen Jillian , Shroyer Kenneth , Selwood David , Tsirka Stella 
Published: November 2023

Gliomas are the most commonly diagnosed primary tumors of the central nervous system (CNS). Median times of survival are dismal regardless of the treatment approach, underlying the need to develop more effective therapies. Modulation of the immune system is a promising strategy as innate and adaptive immunity play important roles in cancer progression. Microglia, the resident macrophages of the CNS, and peripheral macrophages can comprise over 30% of the cells in glioma biopsies. Gliomas secrete cytokines that suppress the anti‐tumorigenic properties of macrophages, causing them to secrete factors that support the tumor's spread and growth. Neuropilin 1 (Nrp1) is a transmembrane receptor that in mice both amplifies pro‐angiogenic signaling in the tumor microenvironment and affects behavior of innate immune cells; we show here that macrophages associated with gliomas in humans similarly express Nrp1. Using a Cre‐lox system, we generated mice that lack expression of Nrp1 in glioma‐associated microglia and macrophages (GAMs). We demonstrate, using an in vivo orthotopic glioma model, that tumors in mice with Nrp1‐deficient GAMs exhibit less vascularity, grow at a slower pace, and are populated by increased numbers of anti‐tumorigenic GAMs. Moreover, glioma survival times in mice with Nrp1‐deficient GAMs increase significantly. Treating wild‐type mice with a small molecule inhibitor of Nrp1's b1 domain, EG00229, which we show here is selective for Nrp1 over Nrp2, yielded an identical outcome. Nrp1‐deficient or EG00229‐treated wild‐type microglia exhibited a shift towards anti‐tumorigenicity as evidence by altered inflammatory marker profiles in vivo and decreased SMAD2/3 activation when conditioned with glioma‐derived factors. These results provide support for the proposal that pharmacological inhibition of Nrp1 constitutes a potential strategy for suppressing glioma progression.Support or Funding InformationThis work was supported by funding from the following grants: 2T32GM008444, 5T32GM007518, and NMSS PP1815.
Serum Starvation Induces a Rapid Increase of Akt Phosphorylation in Ovarian Cancer Cells
Authors: Dai Shuhang , Gocher Angela , Euscher Lindsey , Edelman Arthur 
Published: November 2023

BackgroundCellular stress responses can prevent cell death and help cells to survive in adverse environments. Such responses are important for cancer cells, which are often exposed to cellular stressors such as growth factor deprivation. Depletion of growth factor stimulation may occur in situations such as: metastasis when cancer cells encounter a poorly vascularized environment, angiogenesis inhibitor treatment to reduce blood supply to the tumor or solid tumors in which the central part is deprived of adequate nutrient supply. In vitro, serum starvation is commonly used to mimic growth factor deprivation to reduce activation of kinases under growth factor control, such as Akt.Akt is an oncogene that is activated by the growth factor receptor/PI3K/PDK1 pathway via phosphorylation at Thr 308 to promote cell proliferation and inhibit apoptosis. Hyperactivation of Akt has been shown to promote resistance to first line platinum therapy in ovarian cancer. The canonical Akt activation pathway can be modulated by angiogenesis inhibitors, which are in clinical trials to treat platinum resistant ovarian cancer patients, by reducing tumor blood supply to decrease Akt activation.Previous research suggests that calcium/calmodulin‐dependent protein kinase kinase 2 (CaMKK2) can directly phosphorylate Akt at Thr 308 in a PDK1 independent manner. This suggests that Akt can maintain its activity during serum starvation through multiple mechanisms helping cancer cells to survive stressful conditions. The objectives of the present studies were to investigate whether Akt was activated by serum deprivation and to evaluate the potential role of the PI3K/PDK1/Akt and CaMKK2/Akt pathway in this process.MethodsOVCAR‐3 cells were serum starved for a series of times, then Akt phosphorylation at Thr 308 and expressions levels of CaMKK2 and PDK1 were assessed by Western Blotting. siRNA mediated knockdown of PDK1 and/or CaMKK2 were used to investigate the role of PI3K/PDK1/Akt and CaMKK2/Akt pathway respectively in serum starvation‐induced cellular responses.ResultsSerum starvation increased Akt phosphorylation up to fold at Thr 308 in a time dependent manner in OVCAR‐3 cells. Akt phosphorylation was associated with changes in the expression levels of CaMKK2 and PDK1. Current studies are in process using knockdown of CaMKK2 and/or PDK1 to assess their roles in serum deprivation‐induced Akt phosphorylation.ConclusionsSerum deprivation in cell culture mimics the cellular stress faced by tumor cells in vivo. We used this model to evaluate the cellular stress response in ovarian cancer cells and observed an increase in Akt phosphorylation as well as changes in expression of its upstream activators CaMKK2 and PDK1. We conclude that Akt activation may be important for cancer cells including ovarian cancer cells to survive stressful environments through multiple activation pathways.Support or Funding InformationUniversity at Buffalo Foundation
Synergism of Aldehydes and Cytotoxic Chemotherapy
Authors: Miles Jana S , Flores‐Rozas Hernan 
Published: November 2023

PURPOSEAnthracyclines are frequently used to treat manycancers as single agents or in combination therapy. Triple negative breast cancer is commonly observed in African‐American women (AA) and tends to be more aggressive, carry worse prognoses and is harder to manage because it lacksmolecular targets required for therapies. This leaves anthracyclines as one of the few therapeutic alternatives. Although effective, the use of anthracyclinescan be limited by serious side‐effects and eventually the development of drug resistance. A genome‐wide genetic screening in S. cerevisiae identified mutants of HOM6 as hypersensitivity to doxorubicin. The sensitivity of this strain appears to result from the accumulation of the threonine intermediate L‐aspartate‐semialdehyde since it is abolished by the inactivation of a priorstep. We hypothesize that the accumulation of L‐aspartate‐semialdehydesensitizes the cells to anthracyclines.METHODSUsing S. cerevisiae, survival assay was done to determine the sensitivity of yeast strains (wild type, hom6, hom3, hom3hom6, ydj1, siz1, and msh2)to aldehydes alone and combined with doxorubicin, cisplatin and etoposide. Statistical significance was set atp<0.05.RESULTSCombination of formaldehyde (2 mM) and doxorubicin was moste ffective at reducing cell survival by between 31 to 39‐fold (in wild type cells) relative to doxorubicin and formaldehyde alone. Combination of acetaldehyde (2 mM) and doxorubicin reduced cell survival by between 3 to5‐fold, 5 to 35‐fold, and 1 to 3‐fold in hom3, hom6, and hom3hom6 respectively. This effect was reliant on thedose‐dependent concentration of doxorubicin. Co‐treatment with formaldehyde and doxorubicin of anthracycline‐resistant strains siz1 and msh2 showed increased toxicity (albeit less pronounced) in these strains compared to the wild type.CONCLUSIONThe potential use of a combination of aldehydes andcytotoxic drugs could potentially lead to applications intended to enhanceanthracycline‐based therapy.Support or Funding InformationResearch supported by National Institutes of Health (NIH)under Award Number G12MD007582
Gender differences in the cardiac action of tyramine but not cathinone in the rat
Authors: Docherty James R , Alsufyani Hadeel A 
Published: November 2023

Cathinone is the major active stimulant ingredient of Khat which is chewed by both males and females in approximately equal numbers in countries around the Horn of Africa. We have previously shown that the cardiac β‐adrenoceptor and vascular α‐adrenoceptor mediated actions of cathinone and, for comparison, methylenedioxymethamphetamine (MDMA) are largely indirect by release of noradrenaline (Alsufyani & Docherty, 2015). Until recently, the vast majority of pharmacological studies of stimulants have been carried out employing only male animals, despite the obvious use of stimulants by both males and females in the human population. We have now investigated gender differences in the cardiac actions of cathinone and MDMA in comparison with tyramine in Wistar rats. Animals were sympathectomised by treatment with 6‐hydroxydopamine or treated with vehicle. Residual responses following sympathectomy are likely to be largely direct. In male (230–300g) and female (190–230g) pentobarbitone anaesthetised rats, all three agonists given intravenously produced significant tachycardia but only tyramine produced a large pressor response, MDMA produced small pressor response, and cathinone produced mixed pressor and depressor responses. Sympathectomy virtually abolished the pressor responses to all three agents, and reduced the tachycardia to all three agents, but there were no differences between sympathectomised male and female rats in cardiac responses to any agonist. The tyramine tachycardia was less affected by sympathectomy, suggesting a direct component to the response. In vehicle treated rats, there was no gender difference in the tachycardia to MDMA or cathinone, but the tachycardia to tyramine, in terms of potency, was significantly greater in male than female rats, with a three fold difference in potency. Tyramine potency (−logED50, μg/kg) was 1.59±0.18 (n=8) in male and 2.08±0.14 (n=8) in female rats or 38.9μg/kg and 120μg/kg, respectively (Analysis of Variance and Bonferroni test: P<0.05). Since the mechanism of the tachycardia to tyramine may differ from those of cathinone and MDMA in terms of relative actions at the noradrenaline transporter and the vesicular transporter (Alsufyani & Docherty, 2015), it is concluded that gender differences occur in this system, and that the indirect tachycardia to tyramine is reduced in female rats. Responses to cathinone were unaffected by gender.Support or Funding InformationHAA is funded by a scholarship from the Saudi Government Ministry of Higher Education, KAU.
GPER‐1 Agonist Reduces Angiotensin‐II Induced Oxidative Stress in Rat Aortic Smooth Muscle Cells
Authors: Duong Jennifer Lee , Baker Tyler Pierce , Katakam Prasad , Lindsey Sarah Hoffman 
Published: November 2023

We previously showed that the G protein‐coupled estrogen (GPER) reduces oxidative stress in the kidneys and aorta of female mRen2 rats, a model of angiotensin (Ang) II‐dependent hypertension. The goal of the current study was to assess the mechanisms by which GPER reduces oxidative stress. We hypothesized that GPER activation reduces Ang II‐mediated oxidative stress in rat aortic smooth muscle cells (ASMC) by inhibiting phosphorylation and translocation of Rac1, a small GTPase that recruits subunits to the NADPH oxidase complex. A7r5 cells were treated overnight with either 100 nM of Ang II in the presence of vehicle or 100 nM G‐1. Superoxide levels were measured via electron spin resonance spectroscopy, and RAC and phospho‐RAC were measured via Western blot. Activation of GPER by the agonist G‐1 significantly reduced Ang II‐induced superoxide levels (P<0.05) in AMSC. While there were no significant changes in RAC expression, phospho‐RAC was reduced with G‐1 treatment (P<0.05). We conclude that GPER exerts vascular protection against Ang II‐mediated superoxide production by reducing the phosphorylation of RAC. This anti‐oxidant action of the novel GPER may be one mechanism by which estrogen protects against cardiovascular disease.Support or Funding InformationThis study was funded by National Institutes of Health grant 4R00HL103974 to S.H.L
Chronic Paroxetine Treatment in Mice Leads to Adiposity and Glucose Intolerance
Authors: Zha Weibin , Wang Joanne 
Published: November 2023

Selective serotonin reuptake inhibitors (SSRIs) are the most widely prescribed class of antidepressants for the treatment of depression and anxiety disorders. Recent epidemiologic results have suggested an association between long term use of SSRIs and an increased risk for type 2 diabetes. However, depression itself has been associated with diabetes, and it therefore is unclear whether the association is solely due to SSRI use, depression, or an interaction of both circumstances. The goal of this study is to determine the effects of chronic paroxetine (a common SSRI) treatment on adiposity and glucose tolerance in wild‐type (WT) mice and mice with targeted disruption of serotonin reuptake transporter (SERT−/−). Three ‐to‐four week old male C57BL/6 mice (n=5–6 per group) were treated with paroxetine (10 mg/kg/day) or control vehicle for 12 weeks. This dose is known to achieve serum concentrations in mice comparable to the therapeutic levels in humans. Compared to vehicle control, paroxetine‐treated WT mice exhibited significantly increased weight gain (+20.4±0.7 vs +17.1±0.4 g, P<0.05 vs. WT‐control), adipose tissue expansion, and pro‐lipogenic gene expression. Glucose and insulin tolerance tests further revealed that paroxetine‐treated WT mice exhibited glucose intolerance [glucoseAUC0–120 min(2 g/kg IP following fasting):30.6±0.7 vs. 26.6±0.7g*min/dl, P<0.05 vs. WT‐control] and insulin resistance [glucose AUC0–120 min(following fasting and insulin0.75 units/kg IP): 24.9±1.2 vs. 20.1±1.2g*min/dl, P<0.05 vs. WT‐control]. In parallel, three to‐four week old male SERT−/− mice (n=5–6 per group) were also treated with paroxetine or control vehicle for 12 weeks. Compared to non‐treated SERT−/− mice, paroxetine‐treated SERT−/− mice showed minimal difference in weight gain and a significant attenuation of fat mass expansion. Collectively, these findings demonstrate that chronic paroxetine treatment at a clinically relevant dose leads to adiposity and glucose intolerance in mice, and this effect is largely SERT‐dependent.Support or Funding InformationThis study is supported by NIH grant R01 GM066233 and the Elmer M. Plein Endowment Research Fund.
A Nutraceutical Formulation Improves Cardiometabolic Parameters in Obese/Overweight Subjects
Authors: Nair Sreejayan , Hua Yinan , Ren Dylan Y , Wang Qiurong , Rasmussen Tyler Pat , Smith Derek T , Robinson Timothy J , Nair Rama P , Muhammed Majeed , Kalyanam Nagabhushanam 
Published: November 2023

Obesity is a growing epidemic worldwide and is an independent risk factor for diabetes and cardiovascular disease. GlycaCare™ ‐Plus is a novel proprietary dietary formulation comprising Pterocarpus masupium extract, cinnamon extract, biotin, piperine, magnesium fumarate, zinc monomethionine, copper lysine, chromium polynicotinate and bimaltoxovanadium.The objective of this study was to evaluate the effect of GlycaCare™‐Plus on glucose tolerance and cardiometabolic parameters in a randomized, double blind, placebo‐controlled study.MethodsOverweight or obese subjects (n=21) were randomly assigned to receive either GlycaCareTM Plus oral (500 mg/day) or placebo (microcrystalline cellulose), twice daily, for 90 days. Multiple endpoints including blood pressure, body weight, oral glucose‐tolerance test, serum glucose, insulin, lipid profile, body‐fat distribution, serum markers of inflammation (C‐reactive peptide, interleukin‐6), and serum oxidative stress (8‐isoprostane) were assessed at baseline and after 90‐days following treatment. Subjects receiving GlyacaCare™‐Plus supplement exhibited attenuated insulin resistance as and attenuation of serum oxidative stress compared to those that received placebo, as evidenced by a reduction in HOMA‐IR and serum 8‐isprostane levels respectively in subjects. The supplement did not alter body mass, fat distribution, inflammatory parameters, serum lipids or glucose disposal.ConclusionPreliminary studies demonstrate that GlyacaCare™‐Plus supplement alleviates insulin resistance and reduces plasma oxidative stress in overweight/obese subjects.Support or Funding InformationFunded by a research grant from Sabinsa Corporation, New Jersey.
The Role of CaMKIId in Angiotensin II‐Induced Cardiac Inflammation and Fibrosis
Authors: Willeford Andrew 
Published: November 2023

The Ca2+/calmodulin‐dependent kinase, CaMKIId, is an established mediator of the development of heart failure and myocardial injury. Cardiac inflammation has been increasingly recognized as an important player in these cardiac pathophysiological changes. We previously demonstrated that CaMKIId contributes to cardiac inflammation induced by ischemia/reperfusion through activation of cardiomyocyte nuclear factor kappa B (NF‐kB). In the current study we ask whether angiotensin II (Ang II) promotes cardiac inflammation through CaMKIId and its effects on NF‐kB activation. In addition, Ang II treatment promotes cardiac fibrosis and we hypothesize that this response is initiated through activation of CaMKIId in the cardiomyocyte and subsequent inflammatory responses. Here, we report on preliminary data demonstrating attenuation of inflammatory gene expression (e.g. MCP‐1, MIP1a, IL‐6, TNFa) in cardiomyocyte‐specific CaMKIId KO (CKO) mice following 1 and 7 days of Ang II infusion. In addition, the expression of fibrotic markers (e.g. col1a1, col3a1, TGFβ, and CTGF) in response to Ang II infusion is decreased in CKO mice following 7 days of infusion. This is associated with attenuated fibrosis as evident in histological analysis of CKO vs control heart sections. To note, we do not see increased expression of fibrotic markers after 1 day Ang II infusion, suggesting that inflammation precedes fibrosis. Furthermore, we have demonstrated that inhibition of CCR2, the receptor for MCP‐1, attenuates inflammatory gene expression induced by 1 day of Ang II infusion. Currently, we are determining whether Ang II acts through CaMKIId in the cardiomyocyte to activate NF‐kB‐mediated MCP‐1 gene transcription and whether blockade of CCR2 is sufficient to attenuate Ang II‐induced fibrosis. Findings from these studies may implicate CaMKIId as a promising therapeutic target for attenuating cardiac fibrosis.Support or Funding InformationPharmacology Training Grant (2T32‐GM007752) and UCSD Skaggs School of Pharmacy and Pharmaceutical Sciences
Kruppel‐Like Factor 15: A Critical Transcriptional Regulator Of Hypoxia Induced Endothelial Arginase 2
Authors: Pandey Deepesh , Hori Daijiro , Santhanam Lakshmi , Berkowitz Dan , Romer Lewis 
Published: November 2023

ObjectiveKruppel Like Factor 15 has recently been shown to be critical for activation of proinflammatory processes in vascular smooth muscle and atherogenesis. Although KLF15 is abundantly expressed in vascular endothelium there is a significant lack of knowledge regarding the role of KLF15 in the regulation of vascular endothelial function. Here we tested the hypothesis that a KLF15 is a critical regulator of Arg2 transcription in response to hypoxia.Approach and ResultsAdenovirally mediated overexpression of KLF15 in human pulmonary microvascular endothelial cells (HPMEC) and in rat pulmonary arteries decreased Arg2 mRNA, protein, and activity. HPMECs exposed to 48 hours of hypoxia exhibited a robust increase in Arg2 protein and mRNA expression and a reciprocal decrease in KLF15 protein levels that remain sustained after 24 hours of reoxygenation. Further, decreased KLF15 protein levels observed in hypoxia exposed HPMEC occurs through augmented conjugation of Ubiquitin to KLF15 that results in enhanced clearance of KLF15 via proteasomal degradation. Chromatin immunoprecipitation indicated direct binding of KLF15 to the Arg2 promoter, which was relieved when HPMEC were exposed to hypoxia, Finally, overexpression of KLF15 reversed hypoxia‐induced augmentation of arginase activity and decrements in Nitric Oxide production in HPMEC, and also reversed hypoxia‐induced endothelial dysfunction in isolated mice aortic and rat pulmonary artery rings were.ConclusionsKLF15 is a critical regulator and repressor of endothelial Arg2 expression, and thereby, NO and pulmonary endothelial function. Overexpression or activation of KLF15 may represent novel therapeutic strategies for pulmonary hypertension.Support or Funding InformationNIH R01‐HL089668 NIH R01‐HL124213 American Heart Association Postdoctoral Fellow Award from American Heart Association (13POST16810011) to D. Pandey