Fibrosis-4 index stratifies risks of hepatocellular carcinoma in patients with chronic hepatitis C.

BACKGROUND AND AIMS: Risk stratification for patients with a higher risk of hepatocellular carcinoma (HCC) is crucial. We aimed to investigate the role of the Fibrosis-4 (FIB-4) index in predicting chronic hepatitis C (CHC)-related HCC. METHODS: A retrospective cohort study consecutively included treatment-naive CHC patients receiving longitudinal follow-up at the National Taiwan University Hospital from 1986 to 2014. The clinical data were collected and traced for HCC development. Multivariable Cox proportional hazard regression analysis was used to investigate the predictors for HCC. RESULTS: A total of 1285 patients in the ERADICATE-C cohort were included. The median age was 54, 56% were females, and 933 had HCV viremia. There were 33%, 38%, and 29% of patients having FIB-4 index <1.45, 1.45-3.25, and ≥3.25, respectively. After a median of 9-year follow-up, 186 patients developed HCC. Multivariable analysis revealed that older age, AFP≥20 ng/mL, cirrhosis, and a higher FIB-4 index were independent predictors for HCC. Compared with patients with FIB-4 index <1.45, those with FIB-4 1.45-3.25 had a 5.51-fold risk (95% confidence interval [CI]: 2.65-11.46), and those with FIB-4 ≥ 3.25 had 7.45-fold risk (95% CI: 3.46-16.05) of HCC. In CHC patients without viremia, FIB-4 index 1.45-3.25 and FIB-4 ≥ 3.25 increased 6.78-fold and 16.77-fold risk of HCC, respectively, compared with those with FIB-4 < 1.45. CONCLUSION: The baseline FIB-4 index can stratify the risks of HCC in untreated CHC patients, even those without viremia. The FIB-4 index should thus be included in the management of CHC.

In situ vaccination followed by intramuscular poly-ICLC injections for the treatment of hepatocellular carcinoma in mouse models.

The efficacy of treatment for advanced hepatocellular carcinoma (HCC) has remained limited. Polyinosinic-polycytidylic acid-poly-L-lysine carboxymethylcellulose (poly-ICLC) is a synthetic double-stranded RNA that serves as a viral mimic and induces an immune response. Intratumoral (IT) poly-ICLC injections can induce an autovaccination effect and prime the immune system, whereas intramuscular (IM) injection of poly-ICLC can attract and maintain tumor-specific cytotoxic T lymphocytes in tumors. We found that IT injection of poly-ICLC upregulated the expression of CD83 and CD86 on conventional type 1 dendritic cells in tumors. Combination therapy with IT followed by IM injections of poly-ICLC significantly inhibited tumor growth and increased the tumor-infiltrating CD8+ T cells in two syngeneic mouse models of HCC. Depletion of CD8+ T cells attenuated the antitumor effect. An IFN-γ enzyme-linked immunospot of purified tumoral CD8+ T cells revealed a significant proportion of tumor-specific T cells. Finally, the sequential poly-ICLC therapy induced abscopal effects in two dual-tumor models. This study provides evidence that the sequential poly-ICLC therapy significantly increased infiltration of tumor-specific CD8+ T cells in the tumors and induced CD8+ T cell-dependent inhibition of tumor growth, as well as abscopal effects.

Nerve-mediated expression of histone deacetylases regulates limb regeneration in axolotls.

Axolotls have amazing abilities to regenerate their lost limbs. Nerve and wound epidermis have great impacts on this regeneration. Histone deacetylases (HDACs) have been shown to play roles in the regeneration of amphibian tails and limbs. In this study, a bi-phasic up-regulation of HDAC1 was noted before early differentiation stage of axolotl limb regeneration. Limb regeneration was delayed in larvae incubated with an HDAC inhibitor MS-275. Local injection of MS-275 or TSA, another HDAC inhibitor, into amputation sites of the juveniles did not interfere with wound healing but more profoundly inhibited local HDAC activities and blastema formation/limb regeneration. Elevation of HDAC1 expression was more apparent in wound epidermis than in mesenchyme. Prior denervation prohibited this elevation and limb regeneration. Supplementation of nerve factors BMP7, FGF2, and FGF8 in the stump ends after amputation on denervated limbs not only enabled HDAC1 up-regulation but also led to more extent of limb regeneration. In conclusion, nerve-mediated HDAC1 expression is required for blastema formation and limb regeneration.

Therapeutic Potential of Plasma Proteins Derived from Umbilical Cord Blood for Acute Liver Failure.

There are very limited clinically viable treatment options for acute liver failure, a life-threatening condition that rapidly progresses to loss of liver function. In this study, we aim to evaluate the therapeutic potential of UCBP for acute liver failure induced in a rat model by D-galactosamine (GalN). F344 rats were randomly divided into two groups (control and UCBP-treated) after GalN injection. The therapeutic effects of UCBP were evaluated based on survival rate, H&E staining, TUNEL, PCNA staining, and in vivo BrdU labeling. Hepatocyte proliferation and the therapeutic mechanisms of UCBP were examined with BrdU and Western blot assay in vitro. The survival rate in the UCBP-treated group was found to be increased compared to the control group (85 vs 55%, P = 0.029). UCBP treatment significantly decreased apoptosis and increased cell proliferation. These effects may be secondary to specific bioactive molecules in UCBP. In vitro experiments revealed that adiponectin is one of the key biologically active components of UCBP in facilitating this result and promoting hepatocyte proliferation. Furthermore, this effect is mediated by p38/ERK mitogen-activated protein kinase (MAPK) signaling pathways. Therefore, this uncomplicated and clinically accessible approach may serve as effective bridge therapy for acute liver failure.

Cytoophidium assembly reflects upregulation of IMPDH activity.

Cytidine triphosphate synthase (CTPS) and inosine monophosphate dehydrogenase (IMPDH) (both of which have two isoforms) can form fiber-like subcellular structures termed 'cytoophidia' under certain circumstances in mammalian cells. Although it has been shown that filamentation of CTPS downregulates its activity by disturbing conformational changes, the activity of IMPDH within cytoophidia is still unclear. Most previous IMPDH cytoophidium studies were performed under conditions involving inhibitors that impair GTP synthesis. Here, we show that IMPDH forms cytoophidia without inhibition of GTP synthesis. First, we find that an elevated intracellular CTP concentration or treatment with 3'-deazauridine, a CTPS inhibitor, promotes IMPDH cytoophidium formation and increases the intracellular GTP pool size. Moreover, restriction of cell growth triggers the disassembly of IMPDH cytoophidia, implying that their presence is correlated with active cell metabolism. Finally, we show that the presence of IMPDH cytoophidia in mouse pancreatic islet cells might correlate with nutrient uptake in the animal. Collectively, our findings reveal that formation of IMPDH cytoophidia reflects upregulation of purine nucleotide synthesis, suggesting that the IMPDH cytoophidium plays a role distinct from that of the CTPS cytoophidium in controlling intracellular nucleotide homeostasis.

All-trans retinoic acid ameliorates glycemic control in diabetic mice via modulating pancreatic islet production of vascular endothelial growth factor-A.

Patients with type 1 diabetes mellitus are associated with impairment in vitamin A metabolism. This study evaluated whether treatment with retinoic acid, the biologically active metabolite of vitamin A, can ameliorate diabetes. All-trans retinoic acid (atRA) was used to treat streptozotocin (STZ)-induced diabetic mice which revealed atRA administration ameliorated blood glucose levels of diabetic mice. This hyperglycemic amelioration was accompanied by an increase in the amount of ß cells co-expressed Pdx1 and insulin and by restoration of the vascular laminin expression. The atRA-induced production of vascular endothelial growth factor-A from the pancreatic islets was possibly the key factor that mediated the restoration of islet vascularity and recovery of ß-cell mass. Furthermore, the combination of islet transplantation and atRA administration significantly rescued hyperglycemia in diabetic mice. These findings suggest that vitamin A derivatives can potentially be used as a supplementary treatment to improve diabetes management and glycemic control.

Protection against acetaminophen-induced acute liver failure by omentum adipose tissue derived stem cells through the mediation of Nrf2 and cytochrome P450 expression.

BACKGROUND: Acetaminophen (APAP) overdose causes acute liver failure (ALF) in animals and humans via the rapid depletion of intracellular glutathione (GSH) and the generation of excess reactive oxygen species (ROS) that damage hepatocytes. Stem cell therapy is a potential treatment strategy for ALF. METHODS: We isolated mesenchymal stem cells (MSCs) from mice omentum adipose tissue-derived stem cells (ASCs) and transplanted them into a mouse model of APAP-induced ALF to explore their therapeutic potential. In addition, we performed in vitro co-culture studies with omentum-derived ASCs and primary isolated hepatocytes to demonstrate the hepatoprotective effect of omentum-derived ASCs on hepatocytes that were subjected to APAP-induced damage. RESULT: ASC transplantation significantly improved the survival rate of mice with ALF and attenuated the severity of APAP-induced liver damage by suppressing cytochrome P450 activity to reduce the accumulation of toxic nitrotyrosine and the upregulation of NF-E2-related factor 2 (Nrf2) expression, resulting in an increase in the subsequent antioxidant activity. These effects protected the hepatocytes from APAP-induced damage through the suppression of downstream MAPK signal activation and inflammatory cytokine production. CONCLUSIONS: our results demonstrate that omentum-derived ASCs are an alternative source of ASCs that regulate the antioxidant response and may represent a beneficial therapeutic strategy for ALF.

The specificity and accuracy of (111)In-hexavalent lactoside in estimating liver reserve and its threshold value for mortality in mice.

BACKGROUND & AIMS: The asialoglycoprotein receptor on hepatocyte membranes recognizes the galactose residues of glycoproteins. We investigated the specificity, accuracy and threshold value of asialoglycoprotein receptor imaging for estimating liver reserve via scintigraphy using (111)In-hexavalent lactoside in mouse models. METHODS: (111)In-hexavalent lactoside scintigraphy for asialoglycoprotein receptor imaging was performed on groups of normal mice, orthotopic SK-HEP-1-bearing mice, subcutaneous HepG2-bearing mice, mice with 20-80% partial hepatectomy and mice with acute hepatitis induced by acetaminophen. Liver reserve was measured by relative liver uptake and compared with normal mice. Asialoglycoprotein receptor blockade was performed via an in vivo asialofetuin competitive binding assay. RESULTS: A total of 73.64±7.11% of the injection dose accumulated in the normal liver tissue region, and radioactivity was barely detected in the hepatoma region. When asialoglycoprotein receptor was blocked using asialofetuin, less than 0.41±0.04% of the injection dose was detected as background in the liver. Asialoglycoprotein receptor imaging data revealed a linear correlation between (111)In-hexavalent lactoside binding and residual liver mass (R(2)=0.8548) in 20-80% of partially hepatectomized mice, demonstrating the accuracy of (111)In-hexavalent lactoside imaging for measuring the functional liver mass. Asialoglycoprotein receptor imaging data in mice with liver failure induced using 600mg/kg acetaminophen revealed 19-45% liver reserve relative to normal mice and a fatal threshold value of 25% liver reserve. CONCLUSION: The (111)In-hexavalent lactoside imaging method appears to be a good, specific, visual and quantitative predictor of functional liver reserve. The diagnostic threshold for survival was at 25% liver reserve in mice.

Ectopic DNMT3L triggers assembly of a repressive complex for retroviral silencing in somatic cells.

UNLABELLED: Mammalian genomes are replete with retrotransposable elements, including endogenous retroviruses. DNA methyltransferase 3-like (DNMT3L) is an epigenetic regulator expressed in prospermatogonia, growing oocytes, and embryonic stem (ES) cells. Here, we demonstrate that DNMT3L enhances the interaction of repressive epigenetic modifiers, including histone deacetylase 1 (HDAC1), SET domain, bifurcated 1 (SETDB1), DNA methyltransferase 3A (DNMT3A), and tripartite motif-containing protein 28 (TRIM28; also known as TIF1ß and KAP1) in ES cells and orchestrates retroviral silencing activity with TRIM28 through mechanisms including, but not limited to, de novo DNA methylation. Ectopic expression of DNMT3L in somatic cells causes methylation-independent retroviral silencing activity by recruitment of the TRIM28/HDAC1/SETDB1/DNMT3A/DNMT3L complex to newly integrated Moloney murine leukemia virus (Mo-MuLV) proviral DNA. Concurrent with this recruitment, we also observed the accumulation of histone H3 lysine 9 trimethylation (H3K9me3) and heterochromatin protein 1 gamma (HP1γ), as well as reduced H3K9 and H3K27 acetylation at Mo-MuLV proviral sequences. Ectopic expression of DNMT3L in late-passage mouse embryonic fibroblasts (MEFs) recruited cytoplasmically localized HDAC1 to the nucleus. The formation of this epigenetic modifying complex requires interaction of DNMT3L with DNMT3A as well as with histone H3. In fetal testes at embryonic day 17.5, endogenous DNMT3L also enhanced the binding among TRIM28, DNMT3A, SETDB1, and HDAC1. We propose that DNMT3L may be involved in initiating a cascade of repressive epigenetic modifications by assisting in the preparation of a chromatin context that further attracts DNMT3A-DNMT3L binding and installs longer-term DNA methylation marks at newly integrated retroviruses. IMPORTANCE: Almost half of the mammalian genome is composed of endogenous retroviruses and other retrotransposable elements that threaten genomic integrity. These elements are usually subject to epigenetic silencing. We discovered that two epigenetic regulators that lack enzymatic activity, DNA methyltransferase 3-like (DNMT3L) and tripartite motif-containing protein 28 (TRIM28), collaborate with each other to impose retroviral silencing. In addition to modulating de novo DNA methylation, we found that by interacting with TRIM28, DNMT3L can attract various enzymes to form a DNMT3L-induced repressive complex to remove active marks and add repressive marks to histone proteins. Collectively, these results reveal a novel and pivotal function of DNMT3L in shaping the chromatin modifications necessary for retroviral and retrotransposon silencing.

De novo transcriptome sequencing of axolotl blastema for identification of differentially expressed genes during limb regeneration.

BACKGROUND: Salamanders are unique among vertebrates in their ability to completely regenerate amputated limbs through the mediation of blastema cells located at the stump ends. This regeneration is nerve-dependent because blastema formation and regeneration does not occur after limb denervation. To obtain the genomic information of blastema tissues, de novo transcriptomes from both blastema tissues and denervated stump ends of Ambystoma mexicanum (axolotls) 14 days post-amputation were sequenced and compared using Solexa DNA sequencing. RESULTS: The sequencing done for this study produced 40,688,892 reads that were assembled into 307,345 transcribed sequences. The N50 of transcribed sequence length was 562 bases. A similarity search with known proteins identified 39,200 different genes to be expressed during limb regeneration with a cut-off E-value exceeding 10-5. We annotated assembled sequences by using gene descriptions, gene ontology, and clusters of orthologous group terms. Targeted searches using these annotations showed that the majority of the genes were in the categories of essential metabolic pathways, transcription factors and conserved signaling pathways, and novel candidate genes for regenerative processes. We discovered and confirmed numerous sequences of the candidate genes by using quantitative polymerase chain reaction and in situ hybridization. CONCLUSION: The results of this study demonstrate that de novo transcriptome sequencing allows gene expression analysis in a species lacking genome information and provides the most comprehensive mRNA sequence resources for axolotls. The characterization of the axolotl transcriptome can help elucidate the molecular mechanisms underlying blastema formation during limb regeneration.

Therapeutic Effects of Anti-PD1 Immunotherapy on Hepatocellular Carcinoma Under Administration of Tacrolimus.

BACKGROUND: Liver transplantation (LT) is the treatment of choice for patients with hepatocellular carcinoma (HCC). Recurrence of HCC after LT occurs in 10% to 20% of cases. Preclinical studies to evaluate immune checkpoint inhibitors in conjunction with immunosuppressant treatment in transplant recipients have been lacking. Here, we evaluated the efficacy, safety, and mechanism of programmed cell death-1 (PD1) blockade under tacrolimus treatment in transplant recipients. METHODS: We used a murine allogeneic skin transplantation model and murine syngeneic subcutaneous and orthotopic HCC models and measured the tumor volume and the change in tumor-infiltrating lymphocytes under PD1 blockade and tacrolimus treatment. RESULTS: Tacrolimus treatment prolonged allograft survival in the allogeneic transplantation model and enhanced tumor growth in both subcutaneous and orthotopic HCC models. PD1 blockade suppressed tumor growth and lung metastasis in correlation with the number of infiltrating CD8 + T cells. Under tacrolimus treatment, PD1 blockade still resulted in an antitumor effect accompanied by a significant increase in tumor-infiltrating CD8 + T cells, natural killer cells, dendritic cells, and natural killer T cells. Tacrolimus treatment rescued the acceleration of transplant rejection induced by PD1 blockade in the allogeneic transplantation model. CONCLUSIONS: Our data suggest that treatment with high-dose tacrolimus in conjunction with PD1 blockade has an antitumor effect and reduces transplant rejection in mouse models of allograft skin transplantation and HCC. Thus, these results suggest that a clinical trial of PD1 inhibitors for HCC in LT merits consideration.

Neoantigen vaccination augments antitumor effects of anti-PD-1 on mouse hepatocellular carcinoma.

Immune checkpoint inhibitors are groundbreaking resources for cancer therapy. However, only a few patients with hepatocellular carcinoma (HCC) have shown positive responses to anti-PD-1 therapy. Neoantigens are sequence-altered proteins resulting from somatic mutations in cancer. This study identified the neoantigens of Hep-55.1C and Dt81 Hepa1-6 HCCs by comparing their whole exome sequences with those of a normal C57BL/6 mouse liver. Immunogenic long peptides were pooled as peptide vaccines. The vaccination elicited tumor-reactive immune responses in C57BL/6 mice, as demonstrated by IFN-γ ELISPOT and an in vitro killing assay of splenocytes. In the treatment of three mouse HCC models, combined neoantigen vaccination and anti-PD-1 resulted in more significant tumor regression than monotherapies. Flow cytometry of the tumor-infiltrating lymphocytes showed decreased Treg cells and monocytic myeloid-derived suppressor cells, increased CD8+ T cells, enhanced granzyme B expression, and reduced exhaustion-related markers PD-1 and Lag-3 on CD8+ T cells in the combination group. These findings provide a strong rationale for conducting clinical studies of using neoantigen vaccination in combination with anti-PD-1 to treat patients with HCC.

Dynamic contrast-enhanced magnetic resonance imaging with Gd-EOB-DTPA for the evaluation of liver fibrosis in chronic hepatitis patients.

OBJECTIVES: To develop a non-invasive MRI method for evaluation of liver fibrosis, with histological analysis as the reference standard. METHODS: The study protocol was approved by the Institutional Review Board for Human Studies of our hospital, and written informed consent was obtained from all subjects. Seventy-nine subjects who received dynamic contrast-enhanced MRI (DCE-MRI) with Gd-EOB-DTPA were divided into three subgroups according to Metavir score: no fibrosis (n = 30), mild fibrosis (n = 34), and advanced fibrosis (n = 15). The DCE-MRI parameters were measured using two models: (1) dual-input single-compartment model for arterial blood flow (F (a)), portal venous blood flow, total liver blood flow, arterial fraction (ART), distribution volume, and mean transit time; and (2) curve analysis model for Peak, Slope, and AUC. Statistical analysis was performed with Student's t-test and the nonparametric Kruskal-Wallis test. RESULTS: Slope and AUC were two best perfusion parameters to predict the severity of liver fibrosis (>F2 vs. ≦F2). Four significantly different variables were found between non-fibrotic versus mild-fibrotic subgroups: F (a), ART, Slope, and AUC; the best predictor for mild fibrosis was F (a) (AUROC:0.701). CONCLUSIONS: DCE-MRI with Gd-EOB-DTPA is a noninvasive imaging, by which multiple perfusion parameters can be measured to evaluate the severity of liver fibrosis.

Hepatocellular carcinoma with duodenal invasion and metastasis.

BACKGROUND AND AIM: Hepatocellular carcinoma (HCC) is the leading cause of cancer-related deaths in Taiwan. HCC with duodenal involvement are rare and are associated with a poor prognosis. The purpose of this retrospective study was to collect clinical information and data regarding survival following various treatments. METHODS: Between 1996 and 2009, 21 cases (17 men) were diagnosed with HCC and duodenal invasion and metastases by diagnostic imaging, endoscopy with biopsy, or surgically collected specimens sent to pathology. The clinical course was analyzed from the patients' medical records. RESULTS: Gastrointestinal bleeding was reported in 18/21 patients. Diagnostic imaging showed that the majority of cases involved direct tumor invasion (predominantly from the right liver lobe) and six cases from metastasis. Tumor mass and ulcerations were the most common features noted on endoscopy. In addition to the component therapy and medication treatment, panendoscopic hemostasis, surgery, transcatheter arterial embolization, and radiotherapy were performed for the management of duodenal involvement and gastrointestinal bleeding. Survival duration after duodenal involvement ranged from 0.2 to 57.8 months (mean 10.5 months). CONCLUSIONS: Gastrointestinal bleeding in advanced HCC should raise suspicions of duodenal involvement. HCC can involve the duodenum by direct invasion (from either the left or right liver lobes) or metastasis. The prognosis for HCC patients with duodenal involvement is poor, but is improved by supportive care and application of various treatment modalities.

Green tea extract supplementation ameliorates CCl4-induced hepatic oxidative stress, fibrosis, and acute-phase protein expression in rat.

BACKGROUND/PURPOSE: We evaluated the long-term effects of green tea extract (GTE) supplementation on oxidative stress, biliary acute phase protein expression, and liver function in CCl(4)-induced chronic liver injury. METHODS: We evaluated the antioxidant activity of GTE in comparison with those of vitamin C, vitamin E, and ß-carotene in vitro by using an ultrasensitive chemiluminescence analyzer. Chronic liver injury was induced by intraperitoneally administering carbon tetrachloride (CCl(4)) (1 mL/kg body weight, twice weekly) to female Wistar rats for 8 weeks. The effects of low (4 mg/kg body weight per day) and high (20 mg/kg body weight per day) doses of intragastric GTE on CCl(4)-induced liver dysfunction and fibrosis were examined by measuring the bile and blood reactive oxygen species levels and biochemical parameters by using Western blot and two-dimensional polyacrylamide gel electrophoresis techniques. RESULTS: GTE has greater scavenging activity against O(2)(-), H(2)O(2), and Hypochlorous acid (HOCl) in vitro than vitamin C, vitamin E, and ß-carotene do. In vivo, CCl(4) markedly increased bile and blood reactive oxygen species production, lipid accumulation, number of infiltrated leukocytes, fibrosis, hepatic hydroxyproline content, and plasma alanine aminotransferase and aspartate aminotransferase activities, and reduced plasma albumin levels. Two-dimensional polyacrylamide gel electrophoresis revealed that CCl(4) increased the acute-phase expression of six biliary proteins and decreased hepatic B-cell lymphoma 2 (Bcl-2), catalase, and CuZn superoxide dismutase protein expression. GTE supplementation attenuated CCl(4)-enhanced oxidative stress, levels of biochemical parameters, pathology, and acute-phase protein secretion, and preserved antioxidant/antiapoptotic protein expression. CONCLUSION: GTE supplementation attenuates CCl(4)-induced hepatic oxidative stress, fibrosis, acute phase protein excretion, and hepatic dysfunction via the antioxidant and antiapoptotic defense mechanisms.

Timing Does Matter: Nerve-Mediated HDAC1 Paces the Temporal Expression of Morphogenic Genes During Axolotl Limb Regeneration.

Sophisticated axolotl limb regeneration is a highly orchestrated process that requires highly regulated gene expression and epigenetic modification patterns at precise positions and timings. We previously demonstrated two waves of post-amputation expression of a nerve-mediated repressive epigenetic modulator, histone deacetylase 1 (HDAC1), at the wound healing (3 days post-amputation; 3 dpa) and blastema formation (8 dpa onward) stages in juvenile axolotls. Limb regeneration was profoundly inhibited by local injection of an HDAC inhibitor, MS-275, at the amputation sites. To explore the transcriptional response of post-amputation axolotl limb regeneration in a tissue-specific and time course-dependent manner after MS-275 treatment, we performed transcriptome sequencing of the epidermis and soft tissue (ST) at 0, 3, and 8 dpa with and without MS-275 treatment. Gene Ontology (GO) enrichment analysis of each coregulated gene cluster revealed a complex array of functional pathways in both the epidermis and ST. In particular, HDAC activities were required to inhibit the premature elevation of genes related to tissue development, differentiation, and morphogenesis. Further validation by Q-PCR in independent animals demonstrated that the expression of 5 out of 6 development- and regeneration-relevant genes that should only be elevated at the blastema stage was indeed prematurely upregulated at the wound healing stage when HDAC1 activity was inhibited. WNT pathway-associated genes were also prematurely activated under HDAC1 inhibition. Applying a WNT inhibitor to MS-275-treated amputated limbs partially rescued HDAC1 inhibition, resulting in blastema formation defects. We propose that post-amputation HDAC1 expression is at least partially responsible for pacing the expression timing of morphogenic genes to facilitate proper limb regeneration.

Pancreatic carcinoma cells stimulate proliferation and matrix synthesis of hepatic stellate cells.

BACKGROUND/AIMS: Pancreatic ductal carcinoma cells induce fibrosis by stimulating pancreatic stellate cells to proliferate and synthesize matrix. Desmoplastic reaction has also been observed in liver metastases of pancreatic carcinoma. Hepatic stellate cells are similar to pancreatic stellate cells and may contribute to the desmoplasia associated with liver metastases of pancreatic cancer. The aim of this study was to determine the role of hepatic stellate cells in metastasis. METHODS: Markers of the desmoplastic reaction in tumors induced in nude mice (n=6) by subcutaneously injecting pancreatic carcinoma cells with and without hepatic stellate cells were monitored immunohistochemically. Paracrine stimulation was studied by measuring matrix synthesis (collagen type I and c-fibronectin protein) and cell proliferation. RESULTS: Supernatants of pancreatic carcinoma cells stimulated proliferation of cultured hepatic stellate cells and synthesis of collagen I and c-fibronectin. Preincubation of the supernatants with neutralizing antibodies against fibroblast growth factor 2, transforming growth factor-beta1, and platelet-derived growth factor significantly reduced these stimulatory effects. Subcutaneous injection of hepatic stellate cells induced earlier onset and faster-growth of subcutaneous fibrotic pancreatic tumors in nude mice. CONCLUSIONS: Hepatic stellate cells enhance tumor growth in nude mouse and may play an important role in metastasis formation.

Global gene expression profiling reveals a key role of CD44 in hepatic oval-cell reaction after 2-AAF/CCl4 injury in rodents.

Liver progenitors, so-called oval cells, proliferate remarkably from periportal areas after severe liver injury when hepatocyte regeneration is compromised. These cells invade far into the liver parenchyma. Molecular mechanisms underlying these behaviors of oval cells remain poorly understood. In this study, we treated rats with 2-acetylaminofluorene/carbon tetrachloride to induce hepatic oval cells. By expression microarray analysis, we investigated global gene expression profiles in liver tissue, with an emphasis on adhesion molecules, extracellular matrix proteins, matrix metalloproteinases (MMPs), growth factors/cytokines, and receptors that might contribute to the distinct behaviors of oval cells. Genes upregulated at least twofold were selected. We then performed immunostaining to verify the microarray results and identified expression of MMP-7 and CD44 in oval cells. Staining of cytokeratin (CK)-19, an oval-cell marker, was similar between oval cells located next to periportal areas and those located far within the parenchyma. In contrast, CD44 staining was more intense in the parenchyma than in periportal areas, suggesting a role of CD44 in oval-cell invasion. Moreover, newly differentiated CK-19+ hepatocytes within foci did not show CD44 staining, suggesting that CD44 is related to the undifferentiated oval-cell phenotype. We then investigated oval-cell reactivity in CD44-deficient mice fed an oval cell-inducing diet of 3,5-diethoxycarbonyl-1,4-dihydrocollidine. Results showed significantly reduced oval-cell reactivity in CD44-deficient mice. Thus, oval cells express MMP-7 and CD44, and CD44 appears to play critical roles in the proliferation, invasion, and differentiation of hepatic oval cells in rodents.

Green tea extract supplement reduces D-galactosamine-induced acute liver injury by inhibition of apoptotic and proinflammatory signaling.

Oxidative stress and inflammation contributed to the propagation of acute liver injury (ALI). The present study was undertaken to determine whether D-galactosamine (D-GalN) induces ALI via the mitochondrial apoptosis- and proinflammatory cytokine-signaling pathways, and possible mechanism(s) by which green tea (GT) extract modulates the apoptotic and proinflammatory signaling in rat. D-GalN induced hepatic hypoxia/hypoperfusion and triggered reactive oxygen species (ROS) production from affected hepatocytes, infiltrated leukocytes, and activated Kupffer cells. D-GalN evoked cytosolic Bax and mitochondrial cytochrome C translocation and activated proinflammatory nuclear factor-kappa B (NF-kappaB) and activator protein-1 (AP-1) translocation, contributing to the increase of intercellular adhesion molecule-1 expression, terminal deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL)-positive hepatocytes, multiple plasma cytokines and chemokines release, and alanine aminotransferase (ALT) activity. An altered biliary secretion profile of several acute phase proteins directly indicates oxidative stress affecting intracellular trafficking in the hepatocyte. GT pretreatment attenuated ROS production, mitochondrial apoptosis- and proinflammatory cytokine-signaling pathway, plasma ALT and cytokines levels, biliary acute phase proteins secretion and hepatic pathology by the enhancement of anti-apoptotic mechanisms. In conclusion, D-GalN induced ALI via hypoxia/hypoperfusion-enhanced mitochondrial apoptosis- and proinflammatory cytokine-signaling pathway, contributing to oxidative stress and inflammation in the liver. GT can counteract the D-GalN-induced ALI via the attenuation of apoptotic and proinflammatory signaling by the upregulation of anti-apoptotic mechanism.

Clinical manifestations and survival of hepatocellular carcinoma patients with peritoneal metastasis.

BACKGROUND AND AIM: Peritoneal metastasis is an uncommon manifestation of hepatocellular carcinoma (HCC). The aim of the present paper was to investigate the characteristics and survival of HCC patients with peritoneal metastases. METHODS: From January 1985 to December 2004, we retrospectively reviewed the records of 53 Taiwanese HCC patients with peritoneal metastases. RESULTS: Peritoneal metastases were detected at the time of HCC diagnosis (synchronously) in 10 patients and after the initial therapy for the primary tumors (metachronously) in 43 patients. The mean time for development of the metachronous peritoneal metastases was similar whether the primary cancer was treated with surgery (24 months) or transarterial chemoembolization (22.2 months). The single patient whose primary cancer was treated with supportive care alone developed peritoneal metastasis only 7.5 months after detection of the primary cancer. Surgical resection of the peritoneal metastases was possible in two-thirds of the 43 metachronous patients. The median survival for those who received surgery for these metastases was 12.5 months vs. 2.1 months for those without surgery (P = 0.0013). However, there was no difference in survival if patients were stratified to Child-Pugh grade. CONCLUSIONS: Peritoneal metastases of HCC are rare and can occur synchronously or metachronously. Though increased long-term survival was found in patients who had surgical removal of peritoneal metastases, the main determinant of better survival is Child-Pugh grade.