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14‐3‐3ζ, a phosphopeptide‐binding molecule, is reportedly overexpressed in the cancerous tissues of patients with hepatocellular carcinoma (HCC). Hepatitis B virus (HBV) protein X (HBx) draws intensive attention in HBV‐related HCC because it not only regulates HBV replication, but also promotes carcinogenesis by interacting with various tumor or antitumor molecules. This study is performed to investigate whether and how 14‐3‐3ζ interacts with HBx. The coimmunoprecipitation (Co‐IP) results showed that 14‐3‐3ζ bond to HBx in HBV‐infected Hep3B HCC cells and CSQT‐2 portal vein tumor thrombosis (PVTT) cells. By performing Co‐IP assay in HBV‐free Huh7 cells expressing wild‐type HBx, mutant HBx‐S31A, or HBx‐S31D (serine31 was mutated into alanine31 or aspartic acid31), we found that the phosphorylated serine31 with its near amino acid residues constituted a RPLphosphoS31 GP (R, arginine; P, proline; L, leucine; S, serine; G, glycine) motif in HBx for 14‐3‐3ζ docking. This 14‐3‐3ζ‐HBx interaction was partly impaired when Akt signaling transduction was blocked by LY294002. Furthermore, 14‐3‐3ζ silencing augmented HBx ubiquitination and decreased its expression in cancer cells and xenograft tumor. The migratory and invasive abilities of CSQT‐2 cells were inhibited upon 14‐3‐3ζ silencing, whereas partly restored by HBx overexpression. Additionally, 14‐3‐3ζ positively correlated with HBx to be overexpressed in the primary HCC tissues (r = 0.344) and metastatic PVTT (r = 0.348). In summary, findings of this study reveal a novel 14‐3‐3ζ‐HBx interaction in HCC cells and suggest 14‐3‐3ζ as a candidate target for treating HBV‐related HCC.

Adequate hepatopetal portal vein blood flow is obligatory to ensure proper liver function after liver transplantation. Large collateral veins as shunts impair portal vein flow and even cause hepatofugal blood flow and portal steal syndrome. In particular, splenorenal shunts in liver transplant recipients can lead to allograft dysfunction and possible allograft loss or hepatic encephalopathy. Restoration of portal flow through left renal vein ligation (LRVL) is a treatment option, which is much easier compared to splenectomy, renoportal anastomosis and shunt closure, but bears the risk of moderate and temporary impairment of renal function. In addition, a patent portal vein is mandatory for LRVL. However, although LRVL has been reported to be an effective, safe and easy method to control portacaval shunts and increase hepatopetal flow in some studies, indications and safety are still not clear. In this review, we summarize existing studies on LRVL during liver transplantation.

Decellularized whole organs represent ideal scaffolds for engineering new organs and/or cell transplantation. Here, we investigate whether decellularized liver scaffolds provide cell-friendly biocompatible three-dimensional (3-D) environment to support the proliferation and differentiation of hepatic progenitor cells. Mouse liver tissues are efficiently decellularized through portal vein perfusion. Using the reversibly immortalized mouse fetal hepatic progenitor cells (iHPCs), we are able to effectively recellularize the decellularized liver scaffolds. The perfused iHPCs survive and proliferate in the 3-D scaffolds in vitro for 2 weeks. When the recellularized scaffolds are implanted into the kidney capsule of athymic nude mice, cell survival and proliferation of the implanted scaffolds are readily detected by whole body imaging for 10 days. Furthermore, epidermal growth factor (EGF) is shown to significantly promote the proliferation and differentiation of the implanted iHPCs. Histologic and immunochemical analyzes indicate that iHPCs are able to proliferate and differentiate to mature hepatocytes upon EGF stimulation in the scaffolds. The recellularization of the biomaterial scaffolds is accompanied with vascularization. Taken together, these results indicate that decullarized liver scaffolds effectively support the proliferation and differentiation of iHPCs, suggesting that decellularized liver matrix may be used as ideal biocompatible scaffolds for hepatocyte transplantation.

The cell growth, development, and regeneration of tissue and organ are associated with a large number of gene regulation events, which are mediated in part by transcription factors (TFs) binding to cis-regulatory elements involved in the genome. Predicting the binding affinity and inferring the binding specificity of TF–DNA interactions at the genomic level would be fundamentally helpful for our understanding of the molecular mechanism and biological implication underlying sequence-specific TF–DNA recognition. In this study, we report the development of a combination method to characterize the interaction behavior of a 11-mer oligonucleotide segment and its mutations with the Gcn4p protein, a homodimeric, basic leucine zipper TF, and to predict the binding affinity and specificity of potential Gcn4p binders in the genome-wide scale. In this procedure, a position-mutated energy matrix is created based on molecular modeling analysis of native and mutated Gcn4p–DNA complex structures to describe the position-independent interaction energy profile of Gcn4p with different nucleotide types at each position of the oligonucleotide, and the energy terms extracted from the matrix and their interactives are then correlated with experimentally measured affinities of 19 268 distinct oligonucleotides using statistical modeling methodology. Subsequently, the best one of built regression models is successfully applied to screen those of potential high-affinity Gcn4p binders from the complete genome. The findings arising from this study are briefly listed below: (i) The 11 positions of oligonucleotides are highly interactive and non-additive in contribution to Gcn4p–DNA binding affinity; (ii) Indirect conformational effects upon nucleotide mutations as well as associated subtle changes in interfacial atomic contacts, but not the direct nonbonded interactions, are primarily responsible for the sequence-specific recognition; (iii) The intrinsic synergistic effects among the sequence positions of oligonucleotides determine Gcn4p–DNA binding affinity and specificity; (iv) Linear regression models in conjunction with variable selection seem to perform fairly well in capturing the internal dependences hidden in the Gcn4p–DNA system, albeit ignoring nonlinear factors may lead the models to systematically underestimate and overestimate high- and low-affinity samples, respectively.

Background and Aims: Src family kinases have been suggested to be associated with the metastasis of tumors, but their related mechanisms remain unclear. The aims of the present study were to assess the possible mechanisms by which the inhibition of Fyn activation regulates pancreatic cancer metastasis. Methods: We examined the expressions of Fyn in human pancreatic cancer tissues by immunohistochemistry and systematically investigated the relationship between Fyn expression and pancreatic cancer metastasis. A nude mouse xenograft model induced by BxPC3 cells with or without the inhibition of Fyn activation was used to explore the effect of the inhibition of Fyn on metastasis in vivo. Methyl thiazolyl tetrazolium and terminal deoxynucleotidyl transferase-labeling assays were used to examine the effect of the inhibition of Fyn on the cell proliferation of BxPC3 pancreatic cancer cells in vitro. Reverse transcription polymerase chain reaction and Western blot analysis were performed to explore the possible mechanism of Fyn-induced metastasis. Results: We found that the upregulation of Fyn expression was correlated with human pancreatic cancer metastasis. In BxPC3 pancreatic cancer cells, the inhibition of Fyn activation by kinase-dead Fyn transfection decreased liver metastasis in nude mice. Further analyses showed that Fyn activity modulated pancreatic cell metastasis through the regulation of proliferation and apoptosis. Conclusions: Our results suggest a possible mechanism by which Fyn activity regulates cell proliferation and apoptosis that exerts an effect on pancreatic cancer metastasis.

Background Chronic cholangitis caused by hepatolithiasis is a common disease in Southeast Asia. Few studies have addressed the effects of chronic cholangitis on cyclic activity of the sphincter of Oddi (SO). In this study, we investigated the changes of myoelectric activity in rabbits with chronic cholangitis in vivo and in vitro. Methods Chronic cholangitis was induced in rabbits by initially introducing three pieces of 2–0 silk suture and sequentially injecting E. coli into the choledochus through the tube in ductus cysticus. In in vivo experiments, myoelectric activity of SO was recorded by a circular electrode through the jejunum stump in conscious animals. In in vitro experiments, the SO was completely isolated and the myoelectric activity was recorded by a circular electrode in a 10-mL organ bath filled with Krebs solution, with or without addition of cholecystokinin-8 (CCK-8), KCl, ionomycin or induction of capacitative calcium entry (CCE). Key Results In comparison with control and non-infected rabbits, the rabbits with chronic cholangitis showed higher levels of alkaline phosphatase and γ-glutamyltransferase and significant pathological changes including increased inflammatory infiltration and collagen deposition in mucosae or muscular layer. Cyclic myoelectric activity of SO at phases 2 and 3 of migrating motor complex and the excitatory response to CCK-8 were dramatically decreased in animals with chronic cholangitis. Myoelectric activity of SO was also significantly decreased in vitro with or without agonists or with induction of CCE. Conclusions & Inferences Myoelectric activity of SO and its response to agonists are decreased in rabbits with chronic cholangitis both in vivo and in vitro.