2^(nd) International Symposium on Adipobiology and Adipopharmacology(ISAA) 23-25 October 2009,Varna,Bulgaria Organized by the Bulgarian Society for Cell Biology

Adipobiology, particularly adipoendocrinology, investigates molecular and cellular processes mediated via adipose tissue in health and disease,

EMBO Workshop: 'Cell Biology of the Neuron'

About the Workshop A forum is provided to present the most recent findings in the field of neuronal development, neuronal plasticity and neuronal regeneration emphasizing the intracellular mechanisms and cell biological aspects within these processes.

Highlights of the 2nd International Symposium on Tribbles and Diseases: tribbles tremble in therapeutics for immunity, metabolism, fundamental cell biology and cancer

The Tribbles(TRIB) family of pseudokinase proteins has been shown to play key roles in cell cycle, metabolic diseases, chronic inflammatory disease, and cancer development. A better understanding of the mechanisms of TRIB pseudokinases could provide new insights for disease development and help promote TRIB proteins as novel therapeutic targets for drug discovery. At the 2 nd International Symposium on Tribbles and Diseases held on May 7–9, 2018 in Beijing, China, a group of leading Tribbles scientists reported their findings and ongoing studies about the effects of the different TRIB proteins in the areas of immunity, metabolism, fundamental cell biology and cancer. Here, we summarize important and insightful overviews from 4 keynote lectures, 13 plenary lectures and 8 short talks that took place during this meeting. These findings may offer new insights for the understanding of the roles of TRIB pseudokinases in the development of various diseases.

Skin appendage-derived stem cells: cell biology and potential for wound repair

Stem cells residing in the epidermis and skin appendages are imperative for skin homeostasis and regeneration.These stem cells also participate in the repair of the epidermis after injuries,inducing restoration of tissue integrity and function of damaged tissue.Unlike epidermis-derived stem cells,comprehensive knowledge about skin appendage-derived stem cells remains limited.In this review,we summarize the current knowledge of skin appendage-derived stem cells,including their fundamental characteristics,their preferentially expressed biomarkers,and their potential contribution involved in wound repair.Finally,we will also discuss current strategies,future applications,and limitations of these stem cells,attempting to provide some perspectives on optimizing the available therapy in cutaneous repair and regeneration.

MiRNAs and lncRNAs in NK cell biology and NK/T-cell lymphoma

The important role of lncRNAs and miRNAs in directing immune responses has become increasingly clear.Recent evidence conforms that miRNAs and lncRNAs are involved in NK cell biology and diseases through RNAeprotein,RNAeRNA,or RNAeDNA interactions.In this view,we summarize the contribution of miRNAs and lncRNAs to NK cell lineage devel-opment,activation and function,highlight the biological significance of functional miRNAs or lncRNAs in NKTL and discuss the potential of these miRNAs and lncRNAs as innovative bio-markers/targets for NKTL early diagnosis,target treatment and prognostic evaluations.

The National Natural Science Foundation of China and the Epithelial Cell Biology Research Center

Although it has been only a couple of years since the establishment of the Epithelial Cell Biology Research Center, the first of its kind ever founded in China , the planning for the center establishment and the involvement of the National Natural Science Foundation of China (NSFC) goes way back to more than

Trametinib and dactolisib but not regorafenib exert antiproliferative effects on rat pancreatic stellate cells

BACKGROUND： Modulation of the stroma response is considered a promising approach for the treatment of chronic pancreatitis and pancreatic cancer. The aim of this study was to evaluate the effects of three clinically available small molecule kinase inhibitors, regorafenib, trametinib and dactolisib, on effector functions of activated pancreatic stellate cells （PSCs）, which play a key role in pancreatic fibrosis.

Uncoupling protein 2 deficiency reduces proliferative capacity of murine pancreatic stellate cells

BACKGROUND： Uncoupling protein 2 （UCP2） has been suggested to inhibit mitochondrial production of reactive oxygen species （ROS） by decreasing the mitochondrial membrane potential. Experimental acute pancreatitis is associated with increased UCP2 expression, whereas UCP2 deficiency retards regeneration of aged mice from acute pancreatitis. Here, we have addressed biological and molecular functions of UCP2 in pancreatic stellate cells （PSCs）, which are involved in pancreatic wound repair and fibrogenesis. METHODS： PSCs were isolated from 12 months old （aged） UCP2^-/- mice and animals of the wild-type （WT） strain C57BL/6. Proliferation and cell death were assessed by em- ploying trypan blue staining and a 5-bromo-2＇-deoxyuridine incorporation assay. Intracellular fat droplets were visualized by oil red O staining. Levels of mRNA were determined by RT-PCR, while protein expression was analyzed by immunoblotting and immunofluorescence analysis. Intracellular ROS levels were measured with 2＇,7＇-dichlorofluorescin diacetate. Expression of senescence-associated β-galactosidase （SA β-Gal） was used as a surrogate marker of cellular senescence. RESULTS： PSCs derived from UCP2^-/- mice proliferated at a lower rate than cells from WT mice. In agreement with this observation, the UCP2 inhibitor genipin displayed dose- dependent inhibitory effects on WT PSC growth. Interestingly, ROS levels in PSCs did not differ between the two strains, and PSCs derived from UCP2^-/- mice did not senesce faster than those from corresponding WT cells. PSCs from UCP2^-/- mice and WT animals were also indistinguishable with respect to the activation-dependent loss of intracellular fat droplets, expression of the activation marker α-smooth muscle actin, type I collagen and the autocrine/paracrine mediators interleukin-6 and transforming growth factor-I~ 1. CONCLUSIONS： A reduced proliferative capacity of PSC from aged UCP2^-/- mice may contribute to the retarded regeneration after acute pancreatitis. Apart from their slower growth, PSC of UCP2^-/- mice displayed no functional abnormalities. The antifibrotic potential of UCP2 inhibitors deserves further attention.

Overexpression of transcription factor 3 drives hepatocarcinoma development by enhancing cell proliferation via activating Wnt signaling pathway

Background:Transcription factor 3(TCF3)plays pivotal roles in embryonic development,stem cell maintenance and carcinogenesis.However,its role in hepatocellular carcinoma(HCC)remains largely unknown.This study aimed to analyze the correlation between TCF3 expression and clinicopathological features of HCC,and further explore the underlying mechanism in HCC progression.Methods:The expression of TCF3 was collected from the Cancer Genome Atlas(TCGA)and the Gene Expression Omnibus(GEO)HCC datasets,and further confirmed by immunostaining and Western blotting assays.The correlation between TCF3 expression and the clinicopathological features was evaluated.Bioinformatical analysis and in vitro experiments were conducted to explore the potential role of TCF3 in HCC development.Results:Both the mRNA and protein levels of TCF3 were significantly higher in HCC tumor tissues compared to tumor adjacent tissues(P<0.001 and P<0.01).Analysis based on TCGA datasets showed that TCF3 was positively correlated with tumor clinical stage and grade,and patients with high TCF3 expression had shorter overall survival(P=0.012),disease-specific survival(P=0.022)and progression-free survival(P=0.013).Similarly,the immunostaining results revealed that the high expression of TCF3 was closely correlated with tumor size(P=0.001)and TNM stage(P=0.002),and TCF3 was an independent risk factor of HCC.In vitro study exhibited that TCF3 knockdown dramatically suppressed cancer cell proliferation,and the underlying mechanism might be that the silencing of TCF3 reduced the expression of critical regulating proteins towards cell cycle and proteins involved in Wnt signaling pathways.Conclusions:TCF3 expression is significantly elevated in HCC and positively associated with the tumor size and TNM stage,as well as poor prognosis of HCC patients.The mechanism might be that TCF3 promotes cancer cell proliferation via activating Wnt signaling pathway.

Microscopic Inspection on Developmental Process of Myeloma Cells

The developmental process of Myeloma cells under a digital optical microscope has been inspected and monitored by using time-lapsed recording technique. Myeloma cells were cultured in medium contained 20% and 50% of Fetal Bovine Serum （FBS）, respectively. Inspection and monitoring for 6 hours showed the effect of the FBS to mobility, proliferation rate, and development of cell cycle phases of Myeloma cells. Using time-lapsed data, the speed of cells was 3.5-6.0 pm/s when using FBS 20% and increased to 5.0-8.0 p.m/s when using FBS 50%. The rate of cells decreases from 2 cells/hr when using FBS 20% to 1/6 cells/br when using FBS 50%. The cells division process is signified by the change in gray level and it took every 50-70 minutes.

Protein lysine crotonylation in cellular processions and disease associations

Protein lysine crotonylation(Kcr)is one conserved form of posttranslational modifications of proteins,which plays an important role in a series of cellular physiological and pathological processes.Lysine e-amino groups are the primary sites of such modification,resulting in four-carbon planar lysine crotonylation that is structurally and functionally distinct from the acetylation of these residues.High levels of Kcr modifications have been identified on both histone and non-histone proteins.The present review offers an update on the research progression regarding protein Kcr modifications in biomedical contexts and provides a discussion of the mechanisms whereby Kcr modification governs a range of biological processes.In addition,given the importance of protein Kcr modification in disease onset and progression,the potential viability of Kcr regulators as therapeutic targets is elucidated.

Molecular mechanism of hepatitis B virus-induced hepatocarcinogenesis

Hepatitis B virus(HBV) infection is a global public health problem with approximately 2 billion people that have been exposed to the virus. HBV is a member of a family of small, enveloped DNA viruses called hepadnaviruses, and has a preferential tropism for hepatocytes of mammals and birds. Epidemiological studies have proved a strong correlation between chronic hepatitis B virus infection and the development of hepatocellular carcinoma(HCC). HCC is the fifth most common malignancy with about 700000 new cases each year, and more than 50% of them arise in HBV carriers. A large number of studies describe the way in which HBV can contribute to HCC development. Multiple mechanisms have been proposed, including the accumulation of genetic damage due to immune-mediated hepatic inflammation and the induction of oxidative stress. There is evidence of the direct effects of the viral proteins HBx and HBs on the cell biology. Integration of HBV-DNAinto the human genome is considered an early event in the carcinogenic process and can induce, through insertional mutagenesis, the alteration of gene expression and chromosomal instability. HBV has also epigenetic effects through the modification of the genomic methylation status. Furthermore, the virus plays an important role in the regulation of microRNA expression. This review will summarize the many mechanisms involved in HBV-related liver carcinogenesis.

Inhibition of vascular adhesion protein-1 modifies hepatic steatosis in vitro and in vivo

BACKGROUND Non-alcoholic fatty liver disease(NAFLD)is associated with obesity,insulin resistance and dyslipidaemia and currently is estimated to affect up to a third of all individuals in developed countries.Current standard of care for patients varies according to disease stage,but includes lifestyle interventions common insulin sensitizers,antioxidants and lipid modifiers.However,to date specific therapies have shown little histological or fibrosis stage improvement in large clinical trials,and there is still no licensed therapy for NAFLD.Given the high prevalence,limited treatment options and significant screening costs for the general population,new treatments are urgently required.AIM To assess the potential for inhibition of the amine oxidase enzyme vascular adhesion protein-1(VAP-1)to modify hepatic lipid accumulation in NAFLD.METHODS We have used immunochemical and qPCR analysis to document expression of VAP-1 and key functional proteins and transporters across the NAFLD spectrum.We then utilised hepatocytes in culture and human precision cut liver slices in concert with selective enzyme activity inhibitors to test the effects of activating the semicarbazide-sensitive amine oxidase activity of VAP-1 on hepatic lipid uptake and triglyceride export.A murine model of NAFLD was also used to determine the consequences of VAP-1 knockout and gene expression arrays were used to quantify the effects of VAP-1 activity on key lipid modifying and proinflammatory gene expression.RESULTS We confirmed that increasing severity of NAFLD and progression to cirrhosis was associated with a significant increase in hepatocellular VAP-1 expression.Hepatocytes in vitro exposed to recombinant VAP-1 and its substrate methylamine showed increased lipid accumulation as determined by quantification of Oil Red O uptake.This was recapitulated using hydrogen peroxide,and lipid accumulation was accompanied by changes in expression of the lipid transporter molecules FABP3,FATP6,insulin receptor subunits and PPARα.Human liver tissue exposed to recombinant VAP-1 or substrates for endo/exogenous VAP-1 produced less triglyceride than untreated tissue and demonstrated an increase in steatosis.This response could be inhibited by using bromoethylamine to inhibit the SSAO activity of VAP-1,and mice deficient in VAP-1/AOC3 also demonstrated reduced steatosis on high fat diet.Exposure of human liver tissue to methylamine to activate VAP-1 resulted in increased expression of FABP2 and 4,FATP3-5,caveolin-1,VLDLR,PPARGC1 and genes associated with the inflammatory response.CONCLUSION Our data confirm that the elevations in hepatic VAP-1 expression reported in nonalcoholic steatohepatitis can contribute to steatosis,metabolic disturbance and inflammation.This suggests that targeting the semicarbazide sensitive amine oxidase capacity of VAP-1 may represent a useful adjunct to other therapeutic strategies in NAFLD.

Quantitative Detection of Screening for Cervical Lesions with ThinPrep Cytology Test

OBJECTIVE To investigate the available parameters in gynecological screening for cervical lesions by liquid-based cytology technology （ThinPrep Cytology Test, TCT） and The Bethesda System （TBS）, also with computer image analysis. METHODS With application of the image analysis system, all grades of cervical lesion cells were detected quantitatively and sorted in atypical squamous cells of undetermined significance （ASCUS）, atypical squamous cells-cannot exclude HSIL （ASC-H）, low-grade squamous intraepithelial lesion （LSIL）, high-grade squamous intraepithelial lesion （HSIL） and cervical squamous cell carcinoma （SCC） with the mean optical density （MOD）, average grey （AG）, positive units （PU）, and nucleus to cytoplasmic ratio （N： C）. Differences between each group of cells were compared and analyzed statistically. RESULTS Apart from four stereologic parameters in LSIL and HSIL groups there were no differences among them, in the other groups, there was statistically significant in differences between MOD, AG and PU values. Differences between them in the ratio of nucleus to cytoplasm were highly statistically significant. CONCLUSION Stereological indexes may serve as a screening tool for cervical lesions. The image analysis system is expected to become a new means of cytological assisted diagnosis.

AB040.Pou2f1/2 are required for the specification of cone photoreceptors in the developing retina

Background:Rods and cones are critical for light detection.Although there has been considerable work done in elucidating the molecular mechanisms involved in rod development,not much is known about how the cone cell fate decision is made by the multipotent retinal progenitor cells during development.Analysis of the promoter regions of Nrl and trβ2,rod and cone differentiation factors respectively,revealed DNA binding motifs of two POU-domain containing transcription factors,Pou2f1 and Pou2f2.Preliminary experiments showed that Pou2f1/2 are expressed during the peak of cone genesis in the embryonic retina.Therefore,we hypothesize that Pou2f1/2 specify cone cell fate in the developing retina.Methods:We used immunofluorescence and in situ hybridization to establish the spatiotemporal expression of Pou2f1/2 during retinogenesis.We performed in vivo electroporation in post-natal mice to misexpress Pou2f1/2 and used antibodies specific to proteins expressed in cones such as Rxrγand S-opsin to count cones.Using ex vivo electroporation of embryonic retinal explants,we knocked out Pou2f1 and Pou2f2 using CRISPR/Cas9 gRNAs at the peak of cone production window.Finally,we transfected post-natal retinal explants with a combination of regulatory elements of Nrl or thrb with control backbone vector,Pou2f1 or Pou2f2 using electroporation.Results:We found that Pou2f1/2 are expressed in retinal progenitor cells in the developing retina and subsequently in the differentiated cones.Pou2f1/2 misexpression outside the cone genesis window led to an increase in cones at the expense of rods.Pou2f1/2 indel knockouts generated by CRISPR/Cas9 gRNAs led to a decrease in cones and a converse increase in rods.Finally,we found that Pou2f1/2 activate the cis-regulatory module(CRM)of the thrb gene and repress the activity of the CRM of Nrl.Conclusions:These results uncover novel players that establish the complex gene regulatory network for cone photoreceptor fate specification in the retinal progenitor cells.We anticipate that this work should help us devise improved replacement therapies in the future utilizing stem cells for retinal degenerative diseases such as aged-related macular degeneration(AMD)and Stargardt’s disease.

红细胞免疫作用对胃癌BGC-823细胞标志物表达的影响

目的 探讨红细胞免疫作用对胃癌BGC - 82 3细胞标志物表达的影响以及淋巴细胞的协同作用。方法 应用红细胞免疫粘附肿瘤细胞花环试验、生物化学及放射免疫等方法 ,检测红细胞粘附胃癌细胞(红细胞组 )花环率及红细胞 +淋巴细胞免疫粘附胃癌细胞 (红淋混合组 )花环率 ,红细胞超氧化物歧化酶(SOD)含量 ,胃癌细胞肿瘤标志物癌胚抗原 (CEA)、乳酸脱氢酶 (LDH)、碱性磷酸酶 (ALP)及谷氨酰转移酶 (r-CT)的表达。结果 红细胞组肿瘤红细胞花环率为 (2 8.4 1± 5 .0 1) % ;红细胞组的红细胞SOD含量较对照组显著增高 (P<0 .0 1)红细胞组胃癌细胞CEA、LDH、ALP及r -GT的表达较对照组显著降低 (P<0 .0 1) ) ;与红细胞组相比 ,红淋混合组总花环率显著高于ATER法肿瘤红细胞花环率 (P <0 .0 1) ,淋巴细胞对红细胞免疫粘附胃癌细胞的促进率为 (16 .3± 6 .8) % ,且红淋混合组中肿瘤红细胞、淋巴细胞混合花环率显著高于肿瘤红细胞花环率 (P <0 .0 1)。另外 ,红淋混合组红细胞SOD含量有进一步增高 ;胃癌细胞CEA、LDH、ALP及r-GT表达进一步降低 (P <0 .0 1)。结论 正常人红细胞可免疫粘附体外培养的胃癌BGC - 82 3细胞 ;通过红细胞的免疫作用 ,红细胞SOD合成增加 ,胃癌细胞标志物的表达减少 ;

A brief view of international conference on plant cell wall biology 2017

The triennial International Conference on Plant Cell Wall Biology has been held 5 times since it was initiated in the United States. PCWB2017 for the first time is organized in China. The conference was attended with more than 220 participants and featured with oral and poster presentations, reflecting the contemporarv status of plant cell wall studies.

Understanding the“SMART”features of hematopoietic stem cells and beyond

Since the huge success of bone marrow transplantation technology in clinical practice,hematopoietic stem cells(HSCs)have become the gold standard for defining the properties of adult stem cells(ASCs).Here,we describe the“self-renewal,multilineage differentiation,apoptosis,rest,and trafficking”or“SMART”model,which has been developed based on data derived from studies of HSCs as the most well-characterized stem cell type.Given the potential therapeutic applications of ASCs,we delineate the key characteristics of HSCs using this model and speculate on the physiological relevance of stem cells identified in other tissues.Great strides are being made in understanding the biology of ASCs,and efforts are now underway to develop safe and effective ASC-based therapies in this emerging area.

Cryo-electron microscopy for structural biology:current status and future perspectives

Recently, significant technical breakthroughs in both hardware equipment and software algorithms have enabled cryo-electron microscopy(cryo-EM) to become one of the most important techniques in biological structural analysis. The technical aspects of cryo-EM define its unique advantages and the direction of development. As a rapidly emerging field, cryo-EM has benefitted from highly interdisciplinary research efforts. Here we review the current status of cryo-EM in the context of structural biology and discuss the technical challenges. It may eventually merge structural and cell biology at multiple scales.

Cellular functions of MLL/SET-family histone H3 lysine 4 methyltransferase components

The MLL/SET family of histone H3 lysine 4 methyltransferases form enzyme complexes with core subunits ASH2L, WDR5, RbBP5, and DPY-30 （often abbreviated WRAD）, and are responsible for global histone H3 iysine 4 methylation, a hallmark of actively transcribed chromatin in mammalian cells. Accordingly, the function of these proteins is required for a wide variety of processes including stem cell differentiation, cell growth and division, body segmentation, and hematopoiesis. While most work on MLL-WRAD has focused on the function this core complex in histone methylation, recent studies indicate that MLL-WRAD proteins interact with a variety of other proteins and IncRNAs and can localize to cellular organelles beyond the nucleus. In this review, we focus on the recently described activities and interacting partners of MLL-WRAD both inside and outside the nucleus.