Citations

Human adipose‐derived mesenchymal stromal cells (AMSCs) grown in platelet lysate are promising agents for therapeutic tissue regeneration. Here, we investigated whether manipulation of epigenetic events by the clinically relevant histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA) alters differentiation of AMSCs. The multipotency of AMSCs was validated by their ability to differentiate into osteogenic, chondrogenic, and adipogenic lineages. High‐throughput RNA sequencing and RT‐qPCR established that human histone deacetylases (HDAC1 to HDAC11, and SIRT1 to SIRT7) are differentially expressed in AMSCs. SAHA induces hyper‐acetylation of histone H3 and H4, stimulates protein expression of the HDAC‐responsive gene SLC9A3R1/NHERF1 and modulates the AKT/FOXO1 pathway. Biologically, SAHA interferes with osteogenic, chondrogenic and adipogenic lineage commitment of multipotent AMSCs. Mechanistically, SAHA‐induced loss of differentiation potential of uncommitted AMSCs correlates with multiple changes in the expression of principal transcription factors that control mesenchymal or pluripotent states. We propose that SAHA destabilizes the multi‐potent epigenetic state of uncommitted human AMSCs by hyper‐acetylation and perturbation of key transcription factor pathways. Furthermore, AMSCs grown in platelet lysate may provide a useful biological model for screening of new HDAC inhibitors that control the biological fate of human mesenchymal stromal cells. J. Cell. Physiol. 230: 52–62, 2015. © 2014 Wiley Periodicals, Inc.

AbstractBackground & AimsSurvival of patients with hepatocellular carcinoma (HCC) is determined by hepatic function and tumour extent. Recently, a new Model to Estimate Survival in Ambulatory HCC patients (MESIAH) was proposed to predict overall survival in ambulatory HCC patients. This study aimed to evaluate the prognostic performance of the MESIAH score in an independent cohort of HCC patients.MethodsA cohort of 1969 patients newly diagnosed with HCC at the National Cancer Center, Korea between January 2004 and December 2009 was used for validation of the MESIAH score. The model's performance was assessed using C‐statistics, the likelihood ratio (LR) χ2 value and Akaike information criterion (AIC).ResultsPatients in the cohort had a median age of 56 years and 83.2% were men. Hepatitis B virus infection was present in 74.6 and 81.6% had a Child–Pugh class A. The median overall survival was 21.4 months. The MESIAH score had a higher degree of discrimination, with a C‐statistic of 0.792 [95% confidence interval (CI), 0.782–0.803], when compared with the Barcelona Clinic Liver Cancer (BCLC) staging system [0.665 (95% CI, 0.653–0.678), P < 0.001]. The LR χ2 value and the AIC of MESIAH were also better than those of BCLC, Cancer of the Liver Italian Program, Japan Integrated Scoring and Tokyo score. The observed survival in the cohort closely matched that predicted by the MESIAH score.ConclusionsThe new prognostication model MESIAH accurately estimated the overall survival of Korean HCC patients and may be useful in future research as well as individual patient care.

AbstractRunx2 is the master transcription factor for bone formation. Haploinsufficiency of RUNX2 is the genetic cause of cleidocranial dysplasia (CCD) that is characterized by hypoplastic clavicles and open fontanels. In this study, we found that Pin1, peptidyl prolyl cis–trans isomerase, is a critical regulator of Runx2 in vivo and in vitro. Pin1 mutant mice developed CCD‐like phenotypes with hypoplastic clavicles and open fontanels as found in the Runx2+/− mice. In addition Runx2 protein level was significantly reduced in Pin1 mutant mice. Moreover Pin1 directly interacts with the Runx2 protein in a phosphorylation‐dependent manner and subsequently stabilizes Runx2 protein. In the absence of Pin1, Runx2 is rapidly degraded by the ubiquitin‐dependent protein degradation pathway. However, Pin1 overexpression strongly attenuated uniquitin‐dependent Runx2 degradation. Collectively conformational change of Runx2 by Pin1 is essential for its protein stability and possibly enhances the level of active Runx2 in vivo. J. Cell. Physiol. 228: 2377–2385, 2013. © 2013 Wiley Periodicals, Inc.

In order to develop novel, effective therapies for central nervous system regeneration, it is essential to better understand the role of neurotrophic factors and to design, accordingly, better artificial scaffolds to support both neurite outgrowth and synapse formation. Both nerve growth factor and brain-derived neurotrophic factor are major factors in neural survival, development, synaptogenesis, and synaptic connectivity of primary cultured neurons. As a prime candidate coating material for such neural cultures, carbon nanotubes offer unique structural, mechanical, and electrical properties. In this study, carbon nanotubes coated glass-coverslips were used as the matrix of a primary neural culture system used to investigate the effects of carbon nanotubes on neurite outgrowth and nerve growth factor/brain-derived neurotrophic factor release and expression. For these purposes, we performed comparative analyses of primary cultured neurons on carbon nanotubes coated, non-coated, and Matrigel-coated coverslips. The morphological findings showed definite carbon nanotubes effects on the neurite outgrowths and synaptogenic figures in both cortical and hippocampal neurons when compared with the non-coated negative control. Although the carbon nanotubes did not change neurotrophin expression levels, it stimulated brain-derived neurotrophic factor release into the media from both types of neurons. Accordingly, we suggest a different mechanism of action between carbon nanotubes and Matrigel in relation to the specific neurotrophic factors. Since carbon nanotubes supply long-term extracellular molecular cues for the survival and neurite outgrowths of cultured neurons, the results from this study will contribute to an understanding of carbon nanotubes biological effects and provide new insight into their role in the secretion of neurotrophic factors.

Abstract A previous lectin binding study demonstrated the presence of high molecular-mass mucin-like glycoproteins (HMGP) on the surface of hamster tracheal surface epithelial (HTSE) secretory cells (Proc. Natl. Acad. Sci. USA 1987;84:9304). In the present study, we intended to isolate and characterize these HMGP from the plasma membrane of the primary HTSE cells and then to determine whether or not these membrane HMGP are Muc-1 mucins, a type of mucins originally discovered on the surface of some carcinomas. A subcellular fraction enriched with the plasma membrane was obtained using a sucrose density gradient centrifugation. This fraction contained high molecular-mass glycoconjugates which were excluded from Sepharose CL-4B gel. Biochemical characterization of these glycoconjugates revealed the following characteristics: (1) susceptibility to both pronase and mild alkaline treatments, but totally resistant to proteoglycan-digesting enzymes; (2) partitioning in the detergent phase of Triton X-114 and resistance to digestion by phosphatidylinositol phospholipase C or D; (3) a buoyant density of 1.5 g/ml based on CsCl density gradient centrifugation; (4) polydispersity in terms of both size and charge density; and (5) lack of immunoreactivity with an anti-Muc-1 mucin antibody. We conclude that the plasma membrane of HTSE cells at confluence contains HMGP, which seem to be the integral membrane proteins but different from Muc-1 mucins, and that these membrane HMGP appear to share some similarities with secreted mucins in terms of size and charge.

Background and Purpose— Although thrombolysis in cerebral infarction (TICI) 2b/3 has been regarded as a successful angiographic outcome, the definition or subclassification of TICI 2 has differed between the original (o-TICI) and modified TICI (m-TICI). We sought to compare interobserver variability for both scores and analyze the subgroups of the TICI 2. Methods— Five readers interpreted angiographies independently using a 6-point scale as follows: grade 0, no antegrade flow; grade 1, flow past the initial occlusion without tissue reperfusion; grade 2, partial reperfusion in <50% of the affected territory; grade 3, partial reperfusion in 50% to 66%; grade 4, partial reperfusion in ≥67%; grade 5, complete perfusion. Readings using this scale were then converted into o-TICI and m-TICI score. Statistical analysis was performed according to TICI 2 subgroups. Results— Interobserver agreement was good for the o-TICI and m-TICI scores (intraclass correlation coefficient, 0.73 and 0.67, respectively). Our grade 3 (partial perfusion with 50% to 66%) occupied 19% of total readings, which would have been classified as grade 2a in o-TICI, but as 2b in m-TICI. The m-TICI was more likely to predict good clinical outcome than o-TICI (odds ratio, 2.01 versus 1.63, in reads with TICI 2b/3 versus 0/2a). Conclusions— Both TICI scales showed good agreement among readers. However, the variability in partial perfusion thresholds leads to different grading in ≈20% of cases and may result in significantly different rates of accurate outcome prediction.