Intratumoral Hepatic Stellate Cells as a Poor Prognostic Marker and a New Treatment Target?for?Hepatocellular Carcinoma

Hepatic stellate cells (HSCs), a specialized stromal cytotype in the liver, have been demonstrated to actively contribute to hepatocellular carcinoma (HCC) development. However, the previous studies were performed using HSC cell lines, and the prognostic value of intratumoral HSCs (tHSCs) was unclear. Here we isolated tHSCs from fresh human HCC tissues, and analyzed the abilities of tHSCs to promote HCC progression by using in vitro assays for cell viability, migration and invasion as well as epithelial-mesenchymal transition (EMT) phenotype. 252 HCC patients who underwent hepatectomy were enrolled for analysis of tHSCs and E-cadherin expression in tumor tissues, and 55 HCC patients for analysis of tHSCs in tumor tissues and circulating tumor cells (CTCs) in blood. Prognostic factors were then identified. The results showed that coculture of tHSCs with HCC cells had a stronger effect on HCC cell viability, migration and invasion, accompanied with the acquisition of epithelial-mesenchymal transition (EMT) phenotype. In vivo cotransplantation of HCC cells with tHSCs into nude mice more efficiently promoted tumor formation and growth. Icaritin, a known apoptosis inducer of HSCs, was demonstrated to effectively inhibit tHSC proliferation in vitro and tHSC-induced HCC-promoting effects in vivo. Clinical evidence indicated that tHSCs were rich in 45% of the HCC specimens, tHSC-rich subtypes were negatively correlated either with E-cadherin expression in tumor tissues (r = -0.256, p < 0.001) or with preoperative CTCs in blood (r = -0.287, p = 0.033), and were significantly correlated with tumor size (p = 0.027), TNM staging (p = 0.018), and vascular invasion (p = 0.008). Overall and recurrence-free survival rates of tHSC-rich patients were significantly worse than those for tHSC-poor patients. Multivariate analysis revealed tHSC-rich as an independent factor for overall and recurrence-free survival. In conclusion, tHSCs provide a promising prognostic biomarker and a new treatment target for HCC.     

A microRNA miR-34a-Regulated Bimodal Switch Targets Notch in Colon Cancer Stem Cells

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Highlights? miR-34a regulates colon cancer stem cell asymmetric division ? miR-34a generates a sharp threshold response ? miR-34a converts Notch signaling into a toggle switch ? Binary Notch levels specify self-renewal versus differentiation     

Secreted Frizzled-Related Protein 3 Regulates Activity-Dependent Adult Hippocampal Neurogenesis

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Highlights? Wnt inhibitor sFRP3 exhibits activity-dependent expression in the adult hippocampus ? sFRP3 maintains quiescence of adult hippocampal radial glia-like neural stem cells ? sFRP3 inhibits maturation, dendritic development, and spinal formation of new neurons ? sFRP3 partially mediates activity-dependent adult hippocampal neurogenesis     

Biodegradation of Lignocellulose by White-Rot Fungi: Structural Characterization of Water-Soluble Hemicelluloses

In the biological pretreatment process, white-rot fungi are mostly used to degrade lignin and carbohydrates in lignocellulosic biomass. In this study, water-soluble hemicelluloses were recovered from birch wood (Betula alnoides) decayed by white-rot fungi (Ganoderma lucidum C7016) for different durations up to 16 weeks. Accordingly, the dimethyl sulfoxide (DMSO)-soluble hemicelluloses were isolated from the untreated birch wood as a comparison. Results showed that the fungal-degraded polysaccharides were acidic hemicelluloses having a high content of uronic acids ranging from 20.6 to 22.5 %. Gel permeation chromatography analysis demonstrated that the recovered water-soluble hemicelluloses had a lower average molecular weight (M _w, 15,990–27,560 g?mol^?1) than that of the DMSO-soluble hemicelluloses (M _w , 33,960 g?mol^?1). Fourier transform infrared spectroscopy, scanning electron microscopy, one- and two-dimensional nuclear magnetic resonance spectroscopy also revealed significantly changes between those of fungal degraded and DMSO-soluble hemicelluloses. It was proposed that the hemicelluloses with low molecular weights were easily removed from wood by fungal degradation. This research revealed the changes of hemicelluloses in fungal degradation in the natural environment, which may enable the exploration of novel methods in bioconversion of lignocellulosic biomass for the production of biofuels and biopolymers, in addition to the development of new and better ways to protect wood from biodegradation by microorganisms.     

Removal of a C-terminal serine residue proximal to the inter-chain disulfide bond of a human IgG1 lambda light chain mediates enhanced antibody stability and antibody dependent cell-mediated cytotoxicity

Optimization of biophysical properties is a critical success factor for the developability of monoclonal antibodies with potential therapeutic applications. The inter-domain disulfide bond between light chain (Lc) and heavy chain (Hc) in human IgG1 lends structural support for antibody scaffold stability, optimal antigen binding, and normal Fc function. Recently, human IgG1λ has been suggested to exhibit significantly greater susceptibility to reduction of the inter Lc-Hc disulfide bond relative to the same disulfide bond in human IgG1κ. To understand the molecular basis for this observed difference in stability, the sequence and structure of human IgG1λ and human IgG1κ were compared. Based on this Lc comparison, three single mutations were made in the λ Lc proximal to the cysteine residue, which forms a disulfide bond with the Hc. We determined that deletion of S214 (dS) improved resistance of the association between Lc and Hc to thermal stress. In addition, deletion of this terminal serine from the Lc of IgG1λ provided further benefit, including an increase in stability at elevated pH, increased yield from transient transfection, and improved in vitro antibody dependent cell-mediated cytotoxicity (ADCC). These observations support the conclusion that the presence of the terminal serine of the λ Lc creates a weaker inter-chain disulfide bond between the Lc and Hc, leading to slightly reduced stability and a potential compromise in IgG1λ function. Our data from a human IgG1λ provide a basis for further investigation of the effects of deleting terminal serine from λLc on the stability and function of other human IgG1λ antibodies.     

Genetic variants and signatures of selective sweep of Hanwoo population (Korean native cattle)

Although there have been many studies of native Korean cattle, Hanwoo, there have been no selective sweep studies in these animals. This study was performed to characterize genetic variation and identify selective signatures. We sequencedthe genomes of 12 cattle, and identified 15125420 SNPs, 1768114 INDELs, and 3445 CNVs. The SNPs, INDELs, and CNVs were similarly distributed throughout the genome, and highly variable regions were shown to contain the BoLA family and GPR180, which are related to adaptive immunity. We also identified the domestication footprints of the Hanwoo population by searching for selective sweep signatures, which revealed the RCN2 gene related to BPV resistance. The results of this study may contribute to genetic improvement of the Hanwoo population in Korea. [BMB Reports 2013; 46(7):346-351]     

Network-Level Structural Abnormalities of Cerebral Cortex in Type 1 Diabetes Mellitus

Type 1 diabetes mellitus (T1DM) usually begins in childhood and adolescence and causes lifelong damage to several major organs including the brain. Despite increasing evidence of T1DM-induced structural deficits in cortical regions implicated in higher cognitive and emotional functions, little is known whether and how the structural connectivity between these regions is altered in the T1DM brain. Using inter-regional covariance of cortical thickness measurements from high-resolution T1-weighted magnetic resonance data, we examined the topological organizations of cortical structural networks in 81 T1DM patients and 38 healthy subjects. We found a relative absence of hierarchically high-level hubs in the prefrontal lobe of T1DM patients, which suggests ineffective top-down control of the prefrontal cortex in T1DM. Furthermore, inter-network connections between the strategic/executive control system and systems subserving other cortical functions including language and mnemonic/emotional processing were also less integrated in T1DM patients than in healthy individuals. The current results provide structural evidence for T1DM-related dysfunctional cortical organization, which specifically underlie the top-down cognitive control of language, memory, and emotion.     

Real-Time Fluorescence Loop Mediated Isothermal Amplification for the Detection of Acinetobacter baumannii

Background

Detection of Acinetobacter baumannii has been relying primarily on bacterial culture that often fails to return useful results in time. Although DNA-based assays are more sensitive than bacterial culture in detecting the pathogen, the molecular results are often inconsistent and challenged by doubts on false positives, such as those due to system- and environment-derived contaminations. In addition, these molecular tools require expensive laboratory instruments. Therefore, establishing molecular tools for field use require simpler molecular platforms. The loop-mediated isothermal amplification method is relatively simple and can be improved for better use in a routine clinical bacteriology laboratory. A simple and portable device capable of performing both the amplification and detection (by fluorescence) of LAMP in the same platform has been developed in recent years. This method is referred to as real-time loop-mediated isothermal amplification. In this study, we attempted to utilize this method for rapid detection of A. baumannii.

Methodology and Significant Findings

Species-specific primers were designed to test the utility of this method. Clinical samples of A. baumannii were used to determine the sensitivity and specificity of this system compared to bacterial culture and a polymerase chain reaction method. All positive samples isolated from sputum were confirmed to be the species of Acinetobacter by 16S rRNA gene sequencing. The RealAmp method was found to be simpler and allowed real-time detection of DNA amplification, and could distinguish A. baumannii from Acinetobacter calcoaceticus and Acinetobacter genomic species 3. DNA was extracted by simple boiling method. Compared to bacterial culture, the sensitivity and specificity of RealAmp in detecting A. baumannii was 98.9% and 75.0%, respectively.

Conclusion

The RealAmp assay only requires a single unit, and the assay positivity can be verified by visual inspection. Therefore, this assay has great potential of field use as a molecular tool for detection of A. baumannii.