Biochemistry and Cell Biology
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Published since 1929, this bimonthly journal explores every aspect of general biochemistry.
Below is a collection of manuscripts accepted for publication in BCB. These manuscripts have not undergone copy editing or page composition.
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Below is a collection of manuscripts accepted for publication in BCB. These manuscripts have not undergone copy editing or page composition.
By using TSpace for its journal article repository, CSP grants University of Toronto Libraries a universal non-exclusive license to distribute and preserve all content that CSP deposits in the repository. Copyright of all articles in CSP journals remains with the authors, or the authors' organization, unless specified otherwise, TSpace users must follow the usage rights set out on CSP's web site. Refer to CSP's License to Publish Forms for information on current licensing.
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Item Open Access 1 E-Cadherin knockdown induces cancer stem cell-like phenotype and drug resistance(Canadian Science Publishing, 2021-02-05) Sharma, Anuka; Kaur, Harmandeep; De, Renaissa; Srinivasan, Radhika; Pal, Arnab; Bhattacharyya, ShalmoliCervical cancer is one of the leading causes of mortality amongst women in developing countries and therapy resistance is the main reason for its treatment failure. Recent advances suggest that cancer stem cells (CSCs) are critically involved in regulating the chemo resistant behavior of cervical cancer cells. In our study the CSC phenotype cells were isolated and the expression of stem cell marker and epithelial-mesenchymal transition (EMT) associated gene was confirmed by various assays. However, these CSC phenotype cells cannot be cultured for further cytotoxicity studies. So, we tried to establish a CSC model in cervical cancer cells. We performed the siRNA-mediated knockdown of E-cadherin (E-cad) in these cells and studied EMT associated stem cell-like properties in them. We also performed dose dependent cell viability assay using clinically relevant drugs such as cisplatin, cyclopamine and GANT58 to analyze the drug resistant behavior of these cancer cells. We found that E-cad knockdown induces EMT in cervical cancer cells imparting stem-cell like characteristics along with enhanced tumorsphere formation, migration, invasion ability and drug resistance. This is the first study to establish a CSC model in cervical cancer cells by knockdown of E-cad which can be utilized for development of anti-cancer therapies.Item Open Access 40th International Asilomar Chromatin, Chromosomes and Epigenetics Conference(Canadian Science Publishing, 2019-04-01) Gillespie, Zoe E; Bakhshi, Tanner; Sosa Ponce, Maria Laura; Georgel, Philippe T.; Ausio, JuanThe 40th International Asilomar Chromatin, Chromosomes and Epigenetics Conference was held in the Asilomar Conference Grounds, Pacific Groove California, USA on December 6Th-9th 2018. The organizing committee consisted of established scientists in the fields of chromatin and epigenetics: Sally Pasion and Michael Goldman from the Biology Department, San Francisco State University, CA, USA, Philippe Georgel from the Department of Biological Sciences, Marshal University, WV, USA, Juan Ausiรณ from the Biochemistry and Microbiology, University of Victoria, BC, Canada and Christopher Eskiw from the Department of Biochemistry, University of Saskatchewan, SK, Canada. The meeting had two keynote speakers: Jessica Tyler and Jennifer Mitchell and it covered topics on transcription, replication and repair, epigenetics, cell differentiation and disease, telomeres and centromeres and it had two sessions devoted to nuclear and genomic organization. It encompassed the enthusiastic presentations of excellent trainees within the breathtaking natural setting of Pacific Grove.Item Open Access 43rd International Asilomar Chromatin, Chromosomes, and Epigenetics Conference(Canadian Science Publishing, 2022-06-13) Brown, Joshua A. R.; Cui, Jieying Hazel; Ling, Maggie Y.M.; Gao, Ellia X.C.; Howe, LeAnn J; Teves, Sheila S.The 43rd Asilomar Chromatin, Chromosomes, and Epigenetics Conference was held in an entirely online format from December 9-11, 2021. The conference enabled presenters at various career stages to share promising new findings, and presentations covered modern chromatin research across an array of model systems. Topics ranged from the fundamental principles of nuclear organization and transcription regulation to key mechanisms underlying human disease. The meeting featured five keynote speakers from diverse backgrounds and was organized by: Juan Ausió, University of Victoria (British Columbia, Canada), James Davie, University of Manitoba (Manitoba, Canada), Philippe T. Georgel, Marshall University (West Virginia, USA), Michael Goldman, San Francisco State University (California, USA), LeAnn Howe, University of British Columbia (British Columbia, Canada), Jennifer A. Mitchell, University of Toronto (Ontario, Canada), and Sally G. Pasion, San Francisco State University (California, USA).Item Open Access A Canadian perspective on severe acute respiratory syndrome coronavirus 2 infection and treatment: how prevalent underlying inflammatory disease contributes to pathogenesis(Canadian Science Publishing, 2020-09-16) Willows, Steven Derald; Alam, Syed Benazir; Sandhu, Jagdeep K.; Kulka, MariannaThe coronavirus disease 2019 (COVID-19), a serious respiratory illness caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has emerged as a global pandemic. Canada reported its first case of COVID-19 on 25th January 2020. By March 2020 the virus had spread within Canadian communities reaching the most frail and vulnerable elderly population in long-term care facilities. The majority of cases were reported in the provinces of Quebec, Ontario, Alberta and British Columbia and the highest mortality was seen among individuals aged 65 years or older. Canada has the highest prevalence and incidence rates of several chronic inflammatory diseases, such as multiple sclerosis, inflammatory bowel disease and Parkinson’s disease. Many elderly Canadians also live with comorbid medical illnesses, such as hypertension, diabetes, cardiovascular disease and chronic lung disease and are more likely to suffer from severe COVID-19 with a poor prognosis. It is becoming increasingly evident that underlying inflammatory disease contributes to SARS-CoV-2 pathogenesis. Here, we review the mechanisms of SARS-CoV-2 infection and the host inflammatory responses that lead to resolution or progression to severe COVID-19 disease. Furthermore, we discuss the landscape of COVID-19 therapeutics that are currently in development in Canada.Item Open Access A comparative, cross-species investigation of the properties and roles of transferrin- and lactoferrin-binding protein B from pathogenic bacteria(Canadian Science Publishing, 2016-08-03) Ostan, Nicholas; Morgenthau, Ari; Yu, Rong-hua; Gray-Owen, Scott; Schryvers, Anthony BernardPathogenic bacteria from the families Neisseriaeceae and Moraxellaceae acquire iron from their host using surface receptors that have the ability to hijack iron from the iron-sequestering host proteins, transferrin (Tf) and lactoferrin (Lf). The process of acquiring iron from Tf has been well characterized, including the role of the surface lipoprotein, transferrin-binding protein B (TbpB). In contrast, the only well-defined role for the homologue, LbpB, is in its protection against cationic antimicrobial peptides, which is mediated by regions present in some LbpBs that are highly enriched in glutamic or aspartic acid. In this study we compare the Tf -TbpB and the Lf-LbpB interactions and examine the protective effect of LbpB against extracts from human and transgenic mouse neutrophils to gains insights into the physiological roles of LbpB. The results indicate that, in contrast to the Tf-TbpB interaction, Lf-LbpB interaction is sensitive to pH and salt levels and varies between species. In addition, the results with transgenic mouse neutrophils raise the question of whether there is species specificity in the cleavage of Lf to generate cationic antimicrobial peptides or differences in the potency of peptides derived from mouse and human Lf. .Item Open Access A crosslinked and ribosylated actin trimer does not interact productively with myosin(Canadian Science Publishing, 2018-09-05) Sidhu, Navneet; Dawson, John F.A purified F-actin derived actin trimer that interacts with end-binding proteins did not activate or bind the side-binding protein myosin under rigor conditions. Remodeling of the actin trimer by the binding of gelsolin did not rescue myosin binding, nor did the use of different means of inhibiting the polymerization of the trimer. Our results demonstrate that ADP-ribosylation on all actin subunits of an F-actin derived trimer inhibits myosin binding and that the binding of DNase-I to the pointed end subunits of a crosslinked trimer also remodels the myosin binding site. Taken together, this work highlights the need for a careful balance between modification of actin subunits and maintaining protein-protein interactions to produce a physiologically-relevant short F-actin complex.Item Open Access A deletion variant partially complements a porin-less strain of Neurospora crassa(Canadian Science Publishing, 2016-10-16) Ferens, Fraser G.; Spicer, Victor; Krokhin, Oleg V; Motnenko, Anna; Summers, William A.T.; Court, Deborah AMitochondrial porin, the voltage-dependent anion channel, plays an important role in metabolism and other cellular functions within eukaryotic cells. To further the understanding of porin structure and function, Neurospora crassa wild-type porin was replaced with a deletion variant lacking residues 238-242 (238porin). 238porin was assembled in the mitochondrial outer membrane, but the steady state levels were only about 3% of those of the wild-type protein. The strain harbouring 238porin displayed cytochrome deficiencies and expressed alternative oxidase. Nonetheless, it exhibited an almost normal linear growth rate. Analysis of mitochondrial proteomes from a wild-type strain FGSC 9718, a strain lacking porin (Î Por-1) and that expressing 238porin revealed that the major differences between the variant strains were in the levels of subunits of the NADH:ubiquinone oxidoreductase (complex I) of the electron transport chain, which were reduced only in Î Por-1 strain. These, and other proteins related to electron flow and mitochondrial biogenesis, are differentially affected by relative porin levels.Item Open Access A microplate assay for measuring cell death in C2C12 cells(Canadian Science Publishing, 2018-03-13) Lima, Tanes; Silveira, LeonardoThe main goal of this study was to develop a straightforward and rapid microplate assay for measuring propidium iodide (PI) in C2C12 cells. The PI method proves to be an efficient quantitative assay for analyzing cell viability through PI fluorescence analysis. Importantly, the protocol takes less than 30 minutes, and the results are reproducible. C2C12 cells were exposed to an increasing concentration of palmitate for a period of 24 hours to induce cell death, and the PI fluorescence increased in a concentration-dependent manner. Evaluation of mitochondrial function and reactive oxygen species production validated the deleterious effects of palmitate treatment. Also, the microplate PI assay demonstrated high sensitivity as indicated by the detection of modest fluctuations in cell viability in response to catalase overexpression in palmitate-treated cells. The microplate PI assay, therefore, offers an accurate method to be used for in vitro studies.Item Open Access A prospective on multiple biological activities of lactoferrin contributing to piglet welfare(Canadian Science Publishing, 2020-06-19) Hao, Ya; Wang, Jianhua; Teng, Da; Wang, Xiumin; Mao, Ruoyu; Yang, Na; Ma, XuanxuanPiglets, especially weaning piglets, show a lower level of immunity and higher morbidity and mortality, owing to their rapid growth, physiological immaturity, and gradual reduction of maternal antibodies, which seriously affects their growth and thus, value. It is important that piglets adapt to nutrient digestion and absorption and develop sound intestinal function and colonization with gut microbiota as soon as possible during their early life stage. Lactoferrin is a natural glycoprotein polypeptide that is part of the transferrin family. It is widely found in mucosal secretions such as saliva and tears, and most highly in milk and colostrum. As a multifunctional bioactive protein and a recommended food additive, lactoferrin is a potential alternative therapy to antibiotics and health promoting additive for piglet nutrition and development. It is expected that lactoferrin, as a natural food additive, could play an important role in maintaining pig health and development. This review examines the following known beneficial effects of lactoferrin: improves the digestion and capacity for absorption in the intestinal tract; promotes the absorption of iron and reduces the incidence of iron deficiency anemia; regulates intestinal function and helps to balance the microbial biota; and enhances the resistance to disease of the piglets via modulating and enhancing the immune system.Item Open Access A-kinase Anchoring Protein 5 Anchors Protein Kinase A to Mediate PLN/SERCA to Reduce Cardiomyocyte Apoptosis Induced by Hypoxia and Reoxygenation(Canadian Science Publishing, 2022-01-09) wang, zhi; Zhang, Xu; Zhu, Feng; Zhou, Simin; Wang, Qiushu; Wang, HeguiA-kinase anchoring protein (AKAP) 5 has a variety of biological activities. This study explored whether AKAP5 is involved in cardiomyocyte apoptosis induced by H/R and its possible mechanism. H9C2 cells were used to construct an H/R model in vitro, followed by overexpression of AKAP5 in the cells. Flow cytometry was used to detect the rate of cardiomyocyte apoptosis. The expression of phospholamban (PLN) phosphorylation, SERCA2a and apoptosis-related proteins were determined by western blot. Immunofluorescence staining and immunoprecipitation were used to detect the distribution of and interaction between AKAP5, PKA, and PLN. After H/R induction, H9C2 cells had significantly reduced expression of AKAP5 protein. Upregulation of AKAP5 promoted cell survival and significantly reduced LDH level and apoptosis rate of H9C2 cells. In addition, the overexpression of AKAP5 was accompanied by the activation of the PLN/SERCA2a signaling pathway and a reduction in apoptosis. Immunofluorescence staining and immunoprecipitation revealed that AKAP5 colocalized and interacted with PLN and PKA.Interestingly,St-Ht31 inhibited the effect of AKAP5 overexpression on H/R-induced apoptosis in H9C2 cardiomyocytes. AKAP5 overexpression alleviated H/R-induced cardiomyocyte apoptosis, possibly through anchoring to PKA to mediate the PLN/SERCA pathway, suggesting that AKAP5 is a potential therapeutic target for the prevention and treatment of ischemia-reperfusion injury.Item Open Access Aberrant sphingomyelin 31P-NMR signatures in giant cell tumour of bone(Canadian Science Publishing, 2021-06-01) Quiroz-Acosta, Tayde; Flores-Martinez, Yazmin Montserrat; Becerra-Martnez, Elvia; Prez-Hernndez, Elizabeth; Prez-Hernndez, Nury; Bauelos-Hernndez, Angel ErnestoAn understanding of the biochemistry of the giant cell tumour of bone (GCTB) provides an opportunity for the development of prognostic markers and identification of therapeutic targets. Based on metabolomic analysis, we proposed glycerophospholipid metabolism as the altered pathway in GCTB and the objective of this study was to identify these altered metabolites. Using phosphorus-31 nuclear magnetic resonance spectroscopy (Item Open Access Active vitamin D activates chondrocyte autophagy to reduce osteoarthritis via mediating the AMPK–mTOR signaling pathway(Canadian Science Publishing, 2019-11-24) Kong, Chunyu; Wang, Changlei; Shi, Yuquan; Yan, Lei; Xu, Junhua; Qi, WufangOsteoarthritis (OA) is a common joint degenerative disease. Vitamin D (VD) is essential for bone health. We hypothesized that active VD could be used as a therapeutic treatment for OA. Low serum levels of 25-hydroxyvitamin D [25(OH)D] have been found in patients with OA, and thus the serum level of VD could be diagnostic of OA. To test this, we established a mouse model of OA. The results from staining with hematoxylin–eosin and Safranin O – Fast Green indicated that active VD reduced the symptoms of OA in mice. The results from Western blotting indicated that treatment with VD increased the activity of the p-AMPK–AMPK signaling pathway and decreased the p-mTOR–mTOR pathway; it also increased the ratio of LC3II:LC3I antibodies and the protein expression levels of Beclin-1, but decreased the level of p62. Further, treatment with VD reduced the levels of tumor necrosis factor-α and interleukin-6 both in cartilage tissues and in chondrocytes. Administration of the AMPK inhibitor compound C and autophagy inhibitor 3-methyladenine (3-MA) reversed these changes following VD treatment. In addition, the results from transfection with mRFP-GFP-LC3 indicated that active VD led to autophagosome aggregation in OA chondrocytes. 3-MA inhibited cell autophagy and promoted inflammation in OA. This study provides evidence that active VD activate chondrocyte autophagy to reduce OA inflammation via activating the AMPK–mTOR signaling pathway. Treatment with active VD could be a novel therapeutic option for OA.Item Open Access Adaptations to Excess Choline in Insulin Resistant and Pcyt2 Deficient Skeletal Muscle(Canadian Science Publishing, 2016-08-18) Taylor, Adrian; Schenkel, Laila Cigana; Yokich, Maiya; Bakovic, MaricaIt was hypothesized that choline supplementation in insulin resistant (IR) CTP:phosphoethanolamine cytidylyltransferase deficient (Pcyt2+/-) mice would ameliorate muscle function by remodeling glucose and fatty acid (FA) metabolism. Pcyt2+/- mice either received no treatment or were allowed access to 2 mg/ml choline in drinking water for 4 weeks. Skeletal muscle was harvested from choline treated and untreated mice. Lipid analysis and metabolic gene expression and signaling pathways were compared between untreated Pcyt2+/- mice, treated Pcyt2+/- mice and Pcyt2+/+ mice. The major positive effect of choline supplementation on IR muscle was the reduction of glucose utilization for FA and TAG synthesis and increased muscle glucose storage as glycogen. Choline reduced the expression of genes for FA and TAG formation (Scd1, Fas, Srebp1c, Dgat1/2), upregulated the genes for FA oxidation (Cpt1, PparÎą, Pgc1Îą) and had minor effects on phospholipid and lipolysis genes. Pcyt2+/- muscle had reduced insulin signaling (IRS1), autophagy (LC3) and choline transport (CTL1) proteins that were restored by choline treatment. Additionally, choline activated AMPK and Akt while inhibiting mTORC1 phosphorylation. These data established that choline supplementation could restore muscle glucose metabolism by reducing lipogenesis and improving mitochondrial and intracellular signaling for protein and energy metabolism in insulin resistant Pcyt2 deficient mice.Item Open Access Advances in lactoferrin research concerning bovine mastitis(Canadian Science Publishing, 2016-11-13) Shimazaki, Kei-ichi; Kawai, KazuhiroLactoferrin is a multi-functional, iron-binding glycoprotein found in milk and other exocrine secretions. Lactoferrin in milk plays vital roles in the healthy development of newborn mammals and is also an innate resistance factor involved in the prevention of mammary gland infection by microorganisms. Inflammation of the udder due to bacterial infection is referred to as mastitis. There have been many investigations into the relationships between lactoferrin and mastitis, which fall into several categories. The main categories are fluctuations in the lactoferrin concentration of milk, lactoferrin activities against mastitis pathogens, elucidation of the processes underlying the onset of mastitis, participation of lactoferrin in the immune system, and utilization of lactoferrin in mastitis treatment and prevention. This review article describes lactoferrin research concerning bovine mastitis. In the 1970s, many researchers reported that the lactoferrin concentration fluctuates in milk from cows with mastitis. From the late 1980s, many studies clarified the infection-defense mechanism in the udder and the contribution of lactoferrin to the immune system. After 2000, the processes underlying the onset of mastitis were elucidated in vivo and in vitro, and lactoferrin was applied for the treatment and prevention of mastitis.Item Open Access Aerosolized bovine lactoferrin reduces neutrophils and pro-inflammatory cytokines in mouse models of Pseudomonas aeruginosa lung infections(Canadian Science Publishing, 2016-07-01) Valenti, Piera; Frioni, Alessandra; Rossi, Alice; Ranucci, Serena; De Fino, Ida; Cutone, Antimo; Rosa, Luigi; Bragonzi, Alessandra; Berlutti, FrancescaLactoferrin (Lf), an iron-chelating glycoprotein of the innate immunity, produced by exocrine glands and neutrophils in infection/inflammation sites, is one of the most abundant defence molecules in airway secretions. Lf, a pleiotropic molecule, exerts antibacterial and anti-inflammatory functions. These properties may play a relevant role in airway infections characterized by exaggerate inflammatory response as in Pseudomonas aeruginosa lung infection in cystic fibrosis (CF) subjects. To verify the Lf role in Pseudomonas aeruginosa lung infection, here we evaluated the efficacy of aerosolized bovine Lf (bLf) in mouse models of P. aeruginosa acute and chronic lung infections. C57BL/6NCrl mice were challenged with 106 CFUs of P. aeruginosa PAO1 (acute infection) or MDR-RP73 strain (chronic infection) by intra-tracheal administration. In both acute and chronic infections, aerosolized bLf determined not-significant reduction of bacterial load but significant decrease of the neutrophil recruitment and pro-inflammatory cytokine levels. Moreover, in chronic infection the bLf-treated mice recovered the body weight faster and at higher extent than the control mice. These findings add new insights into the benefits of bLf as a mediator of general health and its potential therapeutic applications.Item Open Access Age-Related Differences in Neuropsychological Assessment of Fetal Alcohol Spectrum Disorder: A Cross-sectional Study(Canadian Science Publishing, 2017-08-03) Taylor, Nicole; Enns, LeahThis cross-sectional study examined six key areas of neuropsychological functioning (cognitive, academic, attention, executive function, adaptive skills) comparing adolescents and school-age children with prenatal alcohol exposure (PAE). The aims were: (1) to examine which neuropsychological measures were predictive of an FASD diagnosis in adolescents and school-age children with PAE, and (2) to compare the neuropsychological performance of adolescents and children diagnosed with FASD. Hierarchical logistic regressions determined that the Full-Scale IQ, Verbal Comprehension and Perceptual Reasoning indices, basic reading and math skills, adaptive functioning at school, and components of executive functioning (dependent on age) improved the probability of an accurate FASD diagnosis in both groups: 9.1% to 19.2% for adolescence and 10.9% to 19.4% for school-age (61.5%-80.9% correct classifications overall). For the age comparison analyses (ANOVAs/MANOVAs), a significant difference was observed in the cognitive domain, as well as with basic math skills (trend) in the FASD diagnosed sample, with lower scores observed for adolescents across these measures. These findings provide further evidence for age differences in neuropsychological assessment as well as increased neuropsychological difficulties in adolescence compared to childhood with FASD. Longitudinal studies will be needed in order to make further inferences about developmental changes in neuropsychological functioning in FASD.Item Open Access Alanyl-glutamine ameliorates lipopolysaccharide-induced inflammation and barrier function injury in bovine jejunum epithelial cells(Canadian Science Publishing, 2019-01-11) Zhang, Xianglun; Tan, Xiuwen; Liu, Yifan; You, Wei; Liu, Guifen; Liu, Xiaomu; Jin, Qing; Wei, Chen; Wan, Fachun; Zhao, HongboThe aim of this study was to investigate the effects of alanyl-glutamine (Ala-Gln) on the regulation of lipopolysaccharide (LPS)-induced inflammation and barrier function in bovine jejunum epithelial cells (BJECs). BJECs were exposed (or not) to 1 μg/mL LPS for 24 h to generate a pro-inflammatory model. The cells were then treated with different concentrations of Ala-Gln (0.25, 0.5, 1.0, 2.0, or 4.0 mmol/L) to detect any regulatory effects on the inflammation and barrier function of BJECs. LPS decreased cell viability and enhanced the production of the pro-inflammatory cytokines interleukin (IL)-6 and IL-8. LPS induced inflammation and damaged the barrier function of BJECs, as evidenced by up-regulated mRNA and protein expression of inflammatory factors and down-regulated expression of tight junction proteins. Conversely, Ala-Gln rescued the decrease in cell viability and prevented the accumulation of ILs after LPS exposure by reducing the mRNA and protein expression levels of inflammatory factors. In addition, Ala-Gln induced the mRNA and protein expression of multiple tight junction proteins, and thus reconstituted the barrier function of BJECs. In conclusion, Ala-Gln attenuates injury from inflammation and repairs damaged intestinal barrier induced with LPS, suggesting its potential as a therapeutic agent against intestinal inflammation in mammals.Item Open Access Alloimperatorin activates apoptosis, ferroptosis and oxeiptosis to inhibit the growth and invasion of breast cancer cells in vitro(Canadian Science Publishing, 2022-02-15) Zhang, Jing; Gao, Run-fang; Li, Jie; Yu, Ke-da; Bi, Kai-xinBreast cancer is the most common malignant tumour in women. Our research on alloimperatorin from Angelica dahurica showed that alloimperatorin inhibited breast cancer cell viability in a concentration- and time-dependent manner; it also showed that apoptosis and ferroptosis inhibitors significantly weakened the anti-survival effect of alloimperatorin. Alloimperatorin clearly induced breast cancer cell apoptosis and increased the activities of Caspase-3, Caspase-8, Caspase-9 and PARP; it also caused significant mitochondrial shrinkage, promoted the accumulation of Fe2+, ROS and MDA, and significantly reduced mRNA and protein expression levels of SLC7A11 and GPX4, indicating that alloimperatorin induces ferroptosis. In addition, alloimperatorin significantly promoted Keap1 expression; although it did not affect the expression of PGAM5 and AIFM1, it significantly reduced the phosphorylation level of AIFM1. After downregulating the expression of Keap1, PGAM5 or AIFM1, the inhibitory effect of alloimperatorin on cell viability was significantly weakened, indicating that alloimperatorin regulates the Keap1/PGAM5/AIFM1 pathway to promote oxeiptosis. Alloimperatorin significantly inhibited the invasion of breast cancer cells, while Keap1 siRNA or GPX4 overexpression vectors significantly enhanced cell invasion and effectively reversed the anti-invasive effect of alloimperatorin. Therefore, alloimperatorin induces breast cancer cell apoptosis, ferroptosis and oxeiptosis, thereby inhibiting cell growth and invasion.Item Open Access Alteration of Bcl11b upon stimulation of both MAP Kinase- and Gsk3-dependent signaling pathways in double negative thymocytes(Canadian Science Publishing, 2018-10-17) Selman, Wisam Hussein; Esfandiari, Elahe; Filtz, Theresa MBcl11b is a transcription factor critical for thymocyte development. We previously characterized the kinetic post-translational modifications (PTMs) of Bcl11b in double positive (DP) thymocytes during stimulation of the T cell receptor-activated MAP kinase pathway. However, the PTMs of Bcl11b in thymocytes from other developmental stages in the thymus, primarily double negative (DN) cells, have not been previously identified. We found that kinetic modifications of Bcl11b in DN cells are somewhat different than the patterns observed in DP cells. Distinct from DP thymocytes, phosphorylation and sumoylation of Bcl11b in DN cells were not oppositely regulated in response to activation of MAP kinase, even though hyper-phosphorylation of Bcl11b coincided with near complete desumoylation. Additionally, prolonged stimulation of the MAP kinase pathway in DN cells, unlike DP thymocytes, did not alter Bcl11b levels of sumoylation or ubiquitinylation, or stability. On the other hand, activation of Wnt/Gsk3-dependent signaling in DN cells resulted in composite dephosphorylation and sumoylation of Bcl11b. Moreover, stimulation of MAP kinase and/or Wnt signaling pathways differentially affects gene expression of some Bcl11b target and maturation- associated genes. Defining the signaling pathways and regulation of sequence-specific transcription factors (SSTFs) by PTMs at various stages of thymopoiesis may improve our understanding of leukemogenesis.Item Open Access Alteration of DACH1 methylation patterns in lung cancer contributes to cell proliferation and migration(Canadian Science Publishing, 2018-03-23) Feng, Yongjie; Wang, Lin; Wang, MingyongLung cancer is the most common cause of cancer-related death. Non-small cell lung cancer (NSCLC) accounts for 80â 85% of total lung cancer cases. Dachshund homolog 1, or DACH1, is a protein encoded by the DACH1 gene in humans. DACH1 inhibits lung adenocarcinoma invasion and tumor growth, but has a lower expression in NSCLC. To investigate the mechanisms of decreased DACH1 expression, its DNA methylation patterns were investigated. The results showed a higher methylation rate in NSCLC compared to in adjacent normal lung tissues. Cell transfection experiments showed that increased methylation impaired transcription factor transactivation. In vivo demethylation treatment and overexpression DACH1 increased apoptosis and decreased migration and invasion in NSCLC A549 cells. Our research provides new insight into NSCLC pathogenesis and identifies a new therapeutic target.