Hepatitis B virus X protein accelerates the development of hepatoma

The chronic infection of hepatitis B virus(HBV) is closely related to the occurrence and development of hepatocellular carcinoma(HCC). Accumulated evidence has shown that HBV X protein(HBx protein) is a multifunctional regulator with a crucial role in hepatocarcinogenesis. However, information on the mechanism by which HBV induces HCC is lacking. This review focuses on the pathological functions of HBx in HBV-induced hepatocarcinogenesis. As a transactivator, HBx can modulate nuclear factor kappa-light-chain-enhancer of activated B cells(NF-κB) and transcription factor AP-2. Moreover, HBx can affect regulatory non-coding RNAs(ncRNAs) including microRNAs and long ncRNAs(lncRNAs), such as miRNA-205 and highly upregulated in liver cancer(HULC), respectively. HBx is also involved in epigenetic modification, including methylation and acetylation. HBx interacts with various signal-transduction pathways, such as protein kinase B/Akt, Wnt/β-catenin, signal transducer and activator of transcription, and NF-κB pathways. Moreover, HBx affects cellular fate by shifting the balance toward cell survival. HBx may lead to the loss of apoptotic functions or directly contributes to oncogenesis by achieving transforming functions, which induce hepatocarcinogenesis. Additionally, HBx can modulate apoptosis and immune response by direct or indirect interaction with host factors. We conclude that HBx hastens the development of hepatoma.

Suppression of tumorigenesis by human mesenchymal stem cells in a hepatoma model

人的间充质的干细胞(hMSCs ) 装家到肿瘤地点并且禁止肿瘤细胞的生长。很少对内在的分子的机制被知道连接 hMSCs 到肿瘤房间的指向的抑制。在这研究，我们从 hMSCs 用一个动物移植模型，一个合作文化系统和调节媒介在二根人的 hepatoma 房间线(H7402 和 HepG2 ) 上调查了 hMSCs 的效果。当 SCID 老鼠与 H7402 细胞和 Z3 hMSCs 的一个相等的数字被注射时，动物移植研究证明肿瘤形成的潜伏的时间被延长并且肿瘤尺寸更小。当 co 有教养时与 Z3 房间， H7402 细胞增殖减少了，增加的 apoptosis，和 Bcl-2 的表示， c-Myc，原子抗原(PCNA ) 和 survivin 低是的增殖的房间调整了。在有调节媒介的处理源于 Z3 hMSC 文化以后， H4702 房间出现了减少的形成殖民地的能力和减少的增长。Immunoblot 分析证明 beta-catenin， Bcl-2， c-Myc， PCNA 和 survivin 表示是在 H7402 和 HepG2 房间调整的 down。总起来说，我们的调查结果证明 hMSCs 禁止 H7402 和 HepG2 人的肝癌症房间线的恶意的显型，它包括增长，形成殖民地的能力和 oncogene 表示试管内和体内。而且，我们的研究提供表明小径的 Wnt 可以在调停 hMSC 的指向和肿瘤房间抑制有一个角色的证据。

Differential expression of bcl-2 and bax genes during the E.coli-induced apoptosis of human U937 cells

To explore the role of bcl-2 and bax genes in the apoptosis of human U937 cells induced by E.coli, flow cytometry assay with annexinⅤ-FITC/PI double staining was used to determine the condition of apoptosis, and the expressions of mRNA of bcl-2 and bax genes were assayed with RT-PCR. It was found that the apoptosis of human U937 cells could be induced by E.coli at various concentration ratios between cells and bacteria for 30 min in a dose-dependent manner. The apoptotic rates at cell/bacteria ratios of 0, 1∶5, 1∶10, 1∶20, 1∶50 and 1∶100 were 3.16%±0.90%, 9.46%±0.84%, 17.90%±1.41%, 35.59%±3.76%, 38.35%±7.12% and 55.07%±5.82% respectively. Also, there was a tendency of alterations in the expression levels of bcl-2 and bax genes with an increased expression level of bax gene and a reduced expression level of bcl-2 gene. It is concluded that E.coli can induce apoptosis in human U937 cells with a down-regulated expression of Bcl-2 and an up-regulated expression of Bax, and this might be related to the induction of apoptosis of the infected cell.

Cloning and identification of an Ubiquitinconjugating enzyme E2 D2 gene from Japanese lamprey Lampetra japonica

The modification of proteins with ubiquitin is an important cellular mechanism for targeting abnormal or short-lived proteins for degradation.Ubiquitin-conjugating enzyme E2 D2 is a protein that is encoded by the UBE2D2 gene.Here,we report a lamprey(La UBE2D2)gene which contained 441-bp open reading frame(ORF)encoding 147 amino acids with a typical UBC domain.Real-time PCR assay showed that the highest expression of the protein in adult lamprey was in the leukocytes,the lowest expression was in the skin,kidney and liver.The high conservation in amino acid sequence of the La UBE2D2protein with the UBE2D2s from Homo sapiens,Danio rerio,Oreochromis niloticus and Takifugu rubripes,implied that it had similar function with UBE2D2proteins from other species.

Role of neuroinflammation in neurodegeneration development

Studies in neurodegenerative diseases,including Alzheimer’s disease,Parkinson’s disease and Amyotrophic lateral sclerosis,Huntington’s disease,and so on,have suggested that inflammation is not only a result of neurodegeneration but also a crucial player in this process.Protein aggregates which are very common pathological phenomenon in neurodegeneration can induce neuroinflammation which further aggravates protein aggregation and neurodegeneration.Actually,inflammation even happens earlier than protein aggregation.Neuroinflammation induced by genetic variations in CNS cells or by peripheral immune cells may induce protein deposition in some susceptible population.Numerous signaling pathways and a range of CNS cells have been suggested to be involved in the pathogenesis of neurodegeneration,although they are still far from being completely understood.Due to the limited success of traditional treatment methods,blocking or enhancing inflammatory signaling pathways involved in neurodegeneration are considered to be promising strategies for the therapy of neurodegenerative diseases,and many of them have got exciting results in animal models or clinical trials.Some of them,although very few,have been approved by FDA for clinical usage.Here we comprehensively review the factors affecting neuroinflammation and the major inflammatory signaling pathways involved in the pathogenicity of neurodegenerative diseases,including Alzheimer’s disease,Parkinson’s disease,and Amyotrophic lateral sclerosis.We also summarize the current strategies,both in animal models and in the clinic,for the treatment of neurodegenerative diseases.

Discovery of highly immunogenic spleen-resident FCGR3^(+)CD103^(+)cDC1s differentiated by IL-33-primed ST2^(+)basophils

Recombinant interleukin-33(IL-33)inhibits tumor growth,but the detailed immunological mechanism is still unknown.IL-33-mediated tumor suppression did not occur in Batf3^(−/−)mice,indicating that conventional type 1 dendritic cells(cDC1s)play a key role in IL-33-mediated antitumor immunity.A population of CD103^(+)cDC1s,which were barely detectable in the spleens of normal mice,increased significantly in the spleens of IL-33-treated mice.The newly emerged splenic CD103^(+)cDC1s were distinct from conventional splenic cDC1s based on their spleen residency,robust effector T-cell priming ability,and surface expression of FCGR3.DCs and DC precursors did not express Suppressor of Tumorigenicity 2(ST2).However,recombinant IL-33 induced spleen-resident FCGR3^(+)CD103^(+)cDC1s,which were found to be differentiated from DC precursors by bystander ST2+immune cells.Through immune cell fractionation and depletion assays,we found that IL-33-primed ST2^(+)basophils play a crucial role in the development of FCGR3^(+)CD103^(+)cDC1s by secreting IL-33-driven extrinsic factors.Recombinant GM-CSF also induced the population of CD103^(+)cDC1s,but the population neither expressed FCGR3 nor induced any discernable antitumor immunity.The population of FCGR3^(+)CD103^(+)cDC1s was also generated in vitro culture of Flt3L-mediated bone marrow-derived DCs(FL-BMDCs)when IL-33 was added in a pre-DC stage of culture.FL-BMDCs generated in the presence of IL-33(FL-33-DCs)offered more potent tumor immunotherapy than control Flt3L-BMDCs(FL-DCs).Human monocyte-derived DCs were also more immunogenic when exposed to IL-33-induced factors.Our findings suggest that recombinant IL-33 or an IL-33-mediated DC vaccine could be an attractive protocol for better tumor immunotherapy.

The labeling of C57BL/6j derived embryonic stem cells with enhanced green fluorescent protein

Objective To labele MESPU35, a embryonic stem (ES) cell line derived from C57BL/6j mouse, with enhanced green fluorescent protein (EGFP) for further application.Methods The EGFP gene was controlled by the hybrid CA promoter/enhancer (CMV enhancer/ chicken beta-actin promoter/ beta-actin intron) to construct the vector of the transgene, pCA-EGFP. The vector was transfected into MESPU35 by electroporation.Results We generated EGFP expressing ES cells demonstrating normal properties. The green fluorescence of EGFP expressing cells was maintained in propagation of the ES cells for more than 30 passages as well as in differentiated cells. Cultured in suspension, the 'green' ES cells aggregated, and formed embryoid bodies maintaining the green fluorescence at varying developmental stages. The 'green' embryoid bodies could expand and differentiate into various types of cells, exhibiting ubiquitous green fluorescence. Conclusions The hybrid CA promoter/enhancer used to control the EGFP expressing ES cells, resulted in more intense and ubiquitous activity. The EGFP transfected cells yield bright green fluorescence, which can be visualized in real time and in situ. In addition, the ES cells, MESPU35, are derived from C57BL/6j mice, which are the most widely used in oncology, physiology and genetics. Compared to 129 substrains, C57BL/6j mice avoid a number of potential problems apparent in the other strains.

DNA-Binding Domain of AtTRB2 Reveals Unique Features of a Single Myb Histone Protein Family that Binds to Both Arabidopsis- and Human-Type Telomeric DNA Sequences

Dear Editor, Telomeres are specific protein-DNA complexes that pro- tect the ends of eukaryotic chromosomes from fusion and degradation and are maintained by a specialized mecha- nism exerted by telomerase and telomere-binding proteins. Mammalian telomeres contain TTAGGG and are associated with a six-protein （e.g. TRF1, TRF2, TIN2, RAP1, POT1, and TPP1） complex called shelterin （de Lange, 2005）, which was involved in telomere homeostasis. Similarly to mammalian telomeres, telomeres in most plants are maintained by tel- omerase and telomere-associated proteins （e.g. AtTBP1, AtTRP1, AtTRB1, POT1, POT2, KU70, and KU80） and consist of tandem arrays of TTTAGGG. Among telomere-associated proteins in Arabidopsis thaliana, AtTRB proteins belong to the SMH （Single-Myb-Histone）-Iike family, in which proteins are composed of an N-terminal Myb domain, a central his- tone Hl-like globular domain, and a C-terminal coiled-coil region.

Optimization of FRET algorithms for sensitized-emission FRET detection

Sensitized-emission fluorescence resonance energy transfer （FRET） detection method based on three- channel fluorescence microscopy is widely used. Several FRET algorithms, such as NFRET, FRETN, FR, FRETR, and FC/Df, are developed recently to quantitatively gauge and compare FRET signals between different experimental groups. However, the algorithms are difficult to choose and interpret. In this letter, we optimize the suitable yellow fluorescent protein （YFP） to cyan fluorescent protein （CFP） concentration ratio range for the above FRET algorithms. We also test the effect of YFP-to-CFP concentration ratio on the calculated energy transfer efficiency E and use the optimized FRET algorithms in the analysis of fas-associated protein with death domain （FADD） self-association directly in living cells.

DNA Binding Properties and Cytotoxic Activities of Two Trinuclear Ruthenium（Ⅱ） Polypyridyl Complexes

The interactions between two trinuclear Ru（II） complexes and calf thymus DNA（CT DNA） were studied via absorption spectroscopy, reverse salt titrations, binding stoichiometry, DNA melting experiments, as well as viscosity measurement. The results indicate that complexes 1 and 2 bind to DNA via the interaction of the planar π-delocalized system of the complexes with intrinsic binding constants of 4.18 × 10^5 and 3.85 × 10^6 L/tool, respectively, and non-electrostatic binding free energy makes a predominant contribution to the binding free energy. The in vitro cytotoxic activity of complexes 1 and 2 was evaluated by the MTT[3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl- 2H-tetrazolium bromide] method. Complex I shows higher anticancer potency than complex 2 against four tumor cell lines. Further mechanism study indicates that complexes 1 and 2 can cause cell cycle arrest in the G2/M phase.

A pipeline to characterize p53 effectors by integrative cistrome and transcriptome analysis in a genetically-defined organoid model

Tumor-protein 53(p53)is a transcription factor(TF)encoded by TP53(Trp53 in mice)and is a master regulator of tumor-suppressive programs'.Importantly,TP53 is the most frequently mutated gene in human cancer,and its loss of function contributes to tumor development,exemplified by variable p53 mutations detected in 50%-75%of pancreatic cancers.2 From these perceptions,a number of targets transcribed by p53 that confer tumor suppression have been identified.Nevertheless,our understanding of how p53 prevents normal cells from initiating tumorigenesis is still incomplete.To complement this limitation,herein,we established a new approach to identify underlying effectors transcribed by p53 in normal physiology.

TSA1 interacts with CSN1/CSN and may be functionally involved in Arabidopsis seedling development in darkness

The COP9 signalosome （CSN） is a multiprotein complex which participates in diverse cellular and developmental processes. CSN1, one of the subunits of CSN, is essential for assembly of the multiprotein complex via PCI （proteasome, COP9 signalosome and initiation factor 3） domain in the C-terminal half of CSN 1. However, the role of the N-terminal domain （NTD） of CSN 1, which is critical for the function of CSN, is not completely understood. Using a yeast two-hybrid （Y2H） screen, we found that the NTD of CSN1 interacts with TSK-associating protein 1 （TSA1）, a reported CaZ＋-binding protein. The interaction between CSN1 and TSA1 was confirmed by co-immunoprecipitation in Arabidopsis. tsal mutants exhibited a short hypocotyl phenotype in darkness but were similar to wild-type Arabidopsis under white light, which suggested that TSA1 might regulate Arabidopsis hypocotyl development in the dark. Furthermore, the expression of TSA1 was significantly lower in a csnl null mutant （fus6）, while CSN1 expression did not change in a tsal mutant with weak TSAI expression. Together, these findings suggest a functional relationship between TSAI and CSN1 in seedling development.