Triglyceride is strongly associated with nonalcoholic fatty liver disease among markers of hyperlipidemia and diabetes

The aim of the present study was to reveal the metabolic disorders most commonly associated with nonalcoholic fatty liver disease (NAFLD). Triglyceride (TG), high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL), blood glucose (BG) and hemoglobin A1c (HbA1c) were analyzed. NAFLD was diagnosed using abdominal ultrasound (US), and TG, HDL, LDL, BG and HbA1c were immediately collected on the same day and subjected to multivariate regression analysis. Stepwise analysis was performed to select the variables that were closely associated with NAFLD. The patients who were positive for the hepatitis B antigen and hepatitis C antibody were excluded from the study. Additionally, the patients who were prescribed prednisolone or methotrexate were excluded from the study as these agents may cause NAFLD or liver toxicity. The study included 168 and 125 patients with and without NAFLD, respectively. TG, BG and HbA1c were strongly correlated with NAFLD. Among these parameters, TG was the strongest predictor of NAFLD (χ2=9.89, P=0.0017). TG was the parameter that was most strongly associated with NAFLD. In conclusion, elevated TG was a marker of NAFLD.

Sonoporation: Gene transfer using ultrasound

Genes can be transferred using viral or non-viral vectors. Non-viral methods that use plasmid DNA and short interference RNA (siRNA) have advantages, such as low immunogenicity and low likelihood of genomic integration in the host, when compared to viral methods. Non-viral methods have potential merit, but their gene transfer efficiency is not satisfactory. Therefore, new methods should be developed. Low-frequency ultrasound irradiation causes mechanical perturbation of the cell membrane, allowing the uptake of large molecules in the vicinity of the cavitation bubbles. The collapse of these bubbles generates small transient holes in the cell membrane and induces transient membrane permeabilization. This formation of small pores in the cell membrane using ultrasound allows the transfer of DNA/RNA into the cell. This phenomenon is known as sonoporation and is a gene delivery method that shows great promise as a potential new approach in gene therapy. Microbubbles lower the threshold of cavity formation. Complexes of therapeutic genes and microbubbles improve the transfer efficiency of genes. Diagnostic ultrasound is potentially a suitable sonoporator because it allows the real-time monitoring of irradiated fields.

Insulin inhibits the activation of transcription by a C-terminal fragment of the forkhead transcription factor FKHR. A mechanism for insulin inhibition of insulin-like growth factor-binding protein-1 transcription

The forkhead rhabdomyosarcoma transcription factor (FKHR) is a promising candidate to be the transcription factor that binds to the insulin response element of the insulin-like growth factor-binding protein-1 (IGFBP-1) promoter and mediates insulin inhibition of IGFBP-1 promoter activity. Cotransfection of mouse FKHR increased IGFBP-1 promoter activity 2-3-fold in H4IIE rat hepatoma cells; insulin inhibited FKHR-stimulated promoter activity approximately 70%. A C-terminal fragment of mouse FKHR (residues 208-652) that contains the transcription activation domain fused to a Gal4 DNA binding domain potently stimulated Gal4 promoter activity. Insulin inhibited FKHR fragment-stimulated promoter activity by approximately 70%. Inhibition was abolished by coincubation with the phosphatidylinositol-3 kinase inhibitor, LY294002. The FKHR 208-652 fragment contains two consensus sites for phosphorylation by protein kinase B (PKB)/Akt, Ser-253 and Ser-316. Neither site is required for insulin inhibition of promoter activity stimulated by the FKHR fragment, and overexpression of Akt does not inhibit FKHR fragment-stimulated Gal4 promoter activity. These results suggest that insulin- and phosphatidylinositol-3 kinase-dependent phosphorylation of another site in the fragment by a kinase different from PKB/Akt inhibits transcription activation by the fragment. Phosphorylation of this site also may be involved in insulin inhibition of transcription activation by full-length FKHR, but only after phosphorylation of Ser-253 by PKB/Akt.

Irradiation with ultrasound of low output intensity increased chemosensitivity of subcutaneous solid tumors to an anti-cancer agent

Ultrasound is a possible mechanical method to deliver small molecules into target cells. In order to evaluate the therapeutic potentials provided by ultrasound irradiation, we compared anti-tumor effects of electroporation- and ultrasound-mediated chemotherapy and efficacy of gene transfer by the two methods. Electric pulses (5 Hz, 100 V/cm, 8 square-wave/100 microsec) or ultrasound (1 MHz, 2 W/cm(2), 5 min) was delivered to subcutaneous solid tumors of murine lymphoma after the tumor-bearing mice received an intraperitoneal injection of bleomycin (BLM) (2.5 mg) or intratumoral injection of plasmid DNA containing the luciferase reporter gene. Administration of BLM alone did not affect the subsequent tumor growth but additive treatment with ultrasound irradiation suppressed the growth to the same level as electroporation. The luciferase activity of the DNA-injected tumors showed that ultrasound irradiation achieved better transfection efficiency than plasmid DNA injection alone but the efficacy was not as great as that by electroporation. The low energy level of ultrasound that is currently used for a diagnostic purpose and physical therapy in clinical fields can thereby increase the in vivo chemosensitivity of treated tumors but further modifications are necessary to achieve better efficacy of the ultrasound-mediated gene transfer.

2-Deoxyglucose and sorafenib synergistically suppress the proliferation and motility of hepatocellular carcinoma cells

Cancer cells consume more glucose than normal cells, mainly due to their increased rate of glycolysis. 2-Deoxy-d-glucose (2DG) is an analogue of glucose, and sorafenib is a kinase inhibitor and molecular agent used to treat hepatocellular carcinoma (HCC). The present study aimed to demonstrate whether combining 2DG and sorafenib suppresses tumor cell proliferation and motility more effectively than either drug alone. HLF and PLC/PRF/5 HCC cells were incubated with sorafenib with or without 1 µM 2DG, and subjected to a proliferation assay. A scratch assay was then performed to analyze cell motility following the addition of 2DG and sorafenib in combination, and each agent alone. RNA was isolated and subjected to reverse transcription-quantitative polymerase chain reaction to analyze the expression of cyclin D1 and matrix metalloproteinase-9 (MMP9) following the addition of 2DG and sorafenib in combination and each agent alone. Proliferation was markedly suppressed in cells cultured with 1 µM 2DG and 30 µM sorafenib compared with cells cultured with either agent alone (P<0.05). In addition, levels of Cyclin D1 expression decreased in cells exposed to 3 µM sorafenib and 1 µM 2DG compared with cells exposed to 2DG or sorafenib alone (P<0.05). Scratch assay demonstrated that the distance between the growing edge of the cell sheet and the scratched line was shorter in cells cultured with sorafenib and 2DG than in cells cultured with 2DG or sorafenib alone (P<0.05). Levels of MMP9 expression decreased more in cells treated with both sorafenib and 2DG than in cells treated with 2DG or sorafenib alone (P<0.05). Therefore, 2DG and sorafenib in combination suppressed the proliferation and motility of HCC cells more effectively than 2DG or sorafenib alone, and a cancer treatment combining both drugs may be more effective than sorafenib alone.

Insulin-like growth factor-I receptor in proliferation and motility of pancreatic cancer

AIM

To develop a molecular therapy for pancreatic cancer, the insulin-like growth factor-I (IGF-I) signaling pathway was analyzed.

METHODS

Pancreatic cancer cell lines (MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4) were cultured in media with 10 mL/L fetal bovine serum. Western blotting analysis was performed to clarify the expression of IGF-I receptor (IGF-IR). Picropodophyllin (PPP), a specific inhibitor of IGF-IR, LY294002, a specific inhibitor of phosphatidylinositol 3 kinase (PI3K), and PD98059, a specific inhibitor of mitogen-activated protein kinase, were added to the media. After 72 h, a 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt (MTS) assay was performed to analyze cell proliferation. A wound assay was performed to analyze cell motility with hematoxylin and eosin (HE) staining 48 h after addition of each inhibitor.

RESULTS

All cell lines clearly expressed not only IGF-IR but also phosphorylated IGF-IR. PPP significantly suppressed proliferation of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 cells to 36.9% +/- 2.4% (mean +/- SD), 30.9% +/- 5.5%, 23.8% +/- 3.9%, 37.1% +/- 5.3%, 10.4% +/- 4.5%, 52.5% +/- 4.5% and 22.6% +/- 0.4%, at 2 micromol/L, respectively (P < 0.05). LY294002 significantly suppressed proliferation of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 cells to 44.4% +/- 7.6%, 32.9% +/- 8.2%, 53.9% +/- 8.0%, 52.8% +/- 4.0%, 32.3% +/- 4.2%, 51.8% +/- 4.5%, and 30.6% +/- 9.4%, at 50 micromol/L, respectively (P < 0.05). PD98059 did not significantly suppress cell proliferation. PPP at 2 micromol/L suppressed motility of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 cells to 3.0% +/- 0.2%, 0%, 0%, 2.0% +/- 0.1%, 5.0% +/- 0.2%, 3.0% +/- 0.1%, and 5.0% +/- 0.2%, respectively (P < 0.05). LY294002 at 50 micromol/L suppressed motility of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 to 3.0% +/- 0.2%, 0%, 3.0% +/- 0.2%, 0%, 0%, 0% and 3% +/- 0.1%, respectively (P < 0.05). PD980509 at 20 micromol/L did not suppress motility. Cells were observed by microscopy to analyze the morphological changes induced by the inhibitors. Cells in medium treated with 2 micromol/L PPP or 50 micromol/L LY294002 had pyknotic nuclei, whereas those in medium with 20 micromol/L PD98059 did not show apoptosis.

CONCLUSION

IGF-IR and PI3K are good candidates for molecular therapy of pancreatic cancer.

Hepatocytes deficient in CCAAT/enhancer binding protein alpha (C/EBP alpha) exhibit both hepatocyte and biliary epithelial cell character

To further elucidate the role of CCAAT/Enhancer Binding Protein alpha (C/EBP alpha) in hepatocyte differentiation, we investigated fetal and newborn C/EBP alpha-deficient (C/EBP alpha -/-) mice using confocal microscopy and markers specific for hepatocyte (AFP) and biliary epithelial cell (A6) differentiation. Histologically, in fetal liver of C/EBP alpha -/- mice, pseudoglandular structures appeared starting at 16.5 days of gestation. In newborn livers, the diameters of these structures greatly increased. They were randomly distributed between portal and central veins and interfered with the establishment of normal hepatic plates. However, the portal bile ducts developed normally. The pseudoglandular structures were lined with small hepatocytes with round nuclei and were positive for both AFP and A6 antigens. These data show that C/EBP alpha -/- hepatocytes exhibit biliary epithelial cell characters and suggest an involvement of C/EBP alpha in the control of the switch in the differentiation of bi-potential hepatoblasts along the hepatocyte lineage.

Growth patterns and interstitial invasion of small hepatocellular carcinoma

Twenty-five cases of small hepatocellular carcinoma (HCC; diameter < or = 30 mm) were evaluated for overall morphologic features and growth patterns. The tumors often showed a well-differentiated, normotrabecular histologic pattern and insidious interstitial invasion, which resembled benign hepatocytes scattered in connective tissues. As the tumor grew, a less-differentiated tumor area became predominant. Portal tracts included in small HCC nodules were quantitatively assessed, revealing that they progressively reduced in number with tumor growth. The tumor margin was often reported to be unclear. The present results indicate that the histologic grade of tumor differentiation, capsular formation, existence of liver cirrhosis and patterns of interstitial invasion are important factors for determining the nature of the margin. The score of argyrophilic nuclear organizer regions (AgNOR) was examined in 5 cases showing typical interstitial invasion with the insidious type. In each case, the AgNOR score of the invading tumor cells was lower than that of tumor cells within the HCC nodules, but higher than benign hepatocytes in cirrhotic parenchyma. It clarified that the growth activity of well-differentiated HCC was rather suppressed upon their interstitial invasion.

Niclosamide suppresses Hepatoma cell proliferation via the Wnt pathway

BACKGROUND

The Wnt pathway plays an important role in Hepatocarcinogenesis. We analyzed the association of the Wnt pathway with the proliferation of hepatoma cells using Wnt3a and niclosamide, a drug used to treat tapeworm infection.

METHODS

We performed an MTS assay to determine whether Wnt3a stimulated proliferation of Huh-6 and Hep3B human hepatoma cell lines after 72 hours of incubation with Wnt3a in serum-free medium. The cells were subjected to hematoxylin and eosin staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) after 48 hours of incubation. RNA was isolated 48 hours after addition of Wnt3a or niclosamide, and cyclin D1 expression levels were analyzed by real-time quantitative polymerase chain reaction. The promoter activity of T-cell factor was analyzed by luciferase assay 48 hours after transfection of TOPflash. Western blot analysis was performed with antibodies against β-catenin, dishevelled 2, and cyclin D1.

RESULTS

Cell proliferation increased with Wnt3a. Niclosamide suppressed proliferation with or without Wnt3a. Hematoxylin and eosin and TUNEL staining suggested that apoptosis occurred in cells with niclosamide. Cyclin D1 was upregulated in the presence of Wnt3a and downregulated with addition of niclosamide. The promoter activity of T-cell factor increased with Wnt3a, whereas T-cell factor promoter activity decreased with niclosamide. Western blot analysis showed that Wnt3a upregulated β-catenin, dishevelled 2, and cyclin D1, while niclosamide downregulated them.

CONCLUSION

Niclosamide is a potential candidate for the treatment of hepatoma.

Patient characteristics with high or low blood urea nitrogen in upper gastrointestinal bleeding

AIM

To examine characteristics of patients with blood urea nitrogen (BUN) levels higher and lower than the normal limit.

METHODS

Patient records between April 2011 and March 2014 were analyzed retrospectively. During this time, 3296 patients underwent upper endoscopy. In total, 50 male (69.2 ± 13.2 years) and 26 female (72.3 ± 10.2 years) patients were assessed. Patients were divided into two groups based on BUN levels: higher than the normal limit (21.0 mg/dL) (H) and lower than the normal limit (L). One-way analysis of variance was performed to reveal differences in the variables between the H and L groups. Fisher's exact test was used to compare the percentage of patients with gastric ulcer or gastric cancer in the H and L groups.

RESULTS

White blood cell count was higher in the H group than in the L group (P = 0.0047). Hemoglobin level was lower in the H group than in the L group (P = 0.0307). Glycated hemoglobin was higher in the H group than in the L group (P = 0.0264). The percentage of patients with gastric ulcer was higher in the H group (P = 0.0002). The H group contained no patients with gastric cancer.

CONCLUSION

Patients with BUN ≥ 21 mg/dL might have more severe upper gastrointestinal bleeding.

A promoter region of the midkine gene that is frequently expressed in human hepatocellular carcinoma can activate a suicide gene as effectively as the alpha-fetoprotein promoter

We examined the expression of the midkine (MK) and alpha-fetoprotein (AFP) genes in 15 paired human specimens obtained from hepatocellular carcinoma (HCC) and the corresponding noncancerous regions of the same patients. A total of 14 HCC but none of the noncancerous specimens were positive for the MK mRNA. In contrast, three HCC specimens and one corresponding noncancerous sample out of the three AFP-positive HCC cases expressed the AFP gene. A 2.3-kb genomic fragment in the regulatory region of the MK gene could activate a fused reporter gene in both AFP-producing and -nonproducing HCC lines, and the MK fragment-mediated transcriptional activity was comparable to the AFP enhancer-linked AFP promoter in AFP-producing cell lines. The AFP-producing but not AFP-nonproducing HCC cell lines that were transfected with the MK promoter-linked herpes simplex virus-thymidine kinase (HSV-TK) gene became susceptible to a prodrug ganciclovir to a similar degree of the HCC transfected with the enhancer-linked AFP promoter-fused HSV-TK gene. These data suggest that the MK promoter can activate a therapeutic gene preferentially in HCC and is as useful as the AFP promoter in clinical settings.

Reduced hemoglobin and increased C-reactive protein are associated with upper gastrointestinal bleeding

AIM

To investigate the early upper gastrointestinal endoscopy (endoscopy) significantly reduces mortality resulting from upper gastrointestinal (GI) bleeding.

METHODS

Upper GI bleeding was defined as 1a, 1b, 2a, and 2b according to the Forrest classification. The hemoglobin (Hb), and C-reactive protein (CRP) were examined at around the day of endoscopy and 3 mo prior to endoscopy. The rate of change was calculated as follows: (the result of blood examination on the day of endoscopy - the results of blood examination 3 mo prior to endoscopy)/(results of blood examination 3 mo prior to endoscopy). Receiver operating characteristic curves were created to determine threshold values.

RESULTS

Seventy-nine men and 77 women were enrolled. There were 17 patients with upper GI bleeding: 12 with a gastric ulcer, 3 with a duodenal ulcer, 1 with an acute gastric mucosal lesion, and 1 with gastric cancer. The area under the curve (AUC), threshold, sensitivity, and specificity of Hb around the day of endoscopy were 0.902, 11.7 g/dL, 94.1%, and 77.1%, respectively, while those of CRP were 0.722, 0.5 mg/dL, 70.5%, and 73%, respectively. The AUC, threshold, sensitivity, and specificity of the rate of change of Hb were 0.851, -21.3%, 76.4%, and 82.6%, respectively, while those of CRP were 0.901, 100%, 100%, and 82.5%, respectively.

CONCLUSION

Predictors for upper GI bleeding were Hb < 11.7 g/dL, reduction rate in the Hb > 21.3% and an increase in the CRP > 100%, 3 mo before endoscopy.

Hepatoblast-like cells enriched from mouse embryonic stem cells in medium without glucose, pyruvate, arginine, and tyrosine

In order to enrich hepatocytes differentiated from embryonic stem cells, we developed a novel medium. Since only hepatocytes have the activity of ornithine transcarbamylase, phenylalanine hydroxylase, galactokinase, and glycerol kinase, we expected that hepatocytes would be enriched in a medium without arginine, tyrosine, glucose, and pyruvate, but supplemented with ornithine, phenylanaline, galactose, and glycerol (hepatocyte-selection medium, HSM). Embryoid bodies were transferred onto dishes coated with gelatin in HSM after 4 days of culture. At 18 days after embryoid body formation, a single type of polygonal cell survived with an enlarged intercellular space and micorvilli. These cells were positive for indocyanine green uptake and for mRNAs of albumin, transthyretin, and alpha-feto protein, but negative for mRNAs of tyrosine aminotransferase, alpha1-antitrypsin, glucose-6-phosphatase, and phosphoenol pyruvate carboxykinase. Since cells in HSM were positive for cytokeratin (CK)8 and CK18 (hepatocyte markers) and for CK19 (a marker of bile duct epithelial cells), we concluded that they were hepatoblasts. They showed weaker expression of CCAAT/enhancer-binding protein (C/EBP)alpha than fetal liver (18.5 days of gestation) and expression of C/EBPbeta at a similar level to that of fetal liver. These data support our conclusion that HSM allows the selection of hepatoblast-like cells.

Survival of primary human hepatocytes and death of induced pluripotent stem cells in media lacking glucose and arginine

BACKGROUND

Tumorigenicity is an associated risk for transplantation of hepatocytes differentiated from human induced pluripotent stem (hiPS) cells. Hepatocytes express the enzymes galactokinase and ornithine transcarbamylase (OTC) to aid in their own survival. However, hiPS cells do not express these enzymes, and therefore, are not be expected to survive in a medium containing galactose and ornithine and lacking glucose and arginine.

MATERIALS AND METHODS

Real-time quantitative polymerase chain reaction (PCR) was performed to analyze the expression of galactokinase 1 (GALK1)1 and GALK2, ornithine carbamyltransferase, and phenylalanine hydroxylase (PAH). The hiPS cell line 201B7 was cultured in hepatocyte selection medium (HSM), which lacks glucose and arginine but contains galactose and ornithine. Furthermore, microscopic analysis of the cultured cells was performed after hematoxylin and eosin (H&E) staining, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL). The hiPS cells were immunostained to assess their pluripotency in HSM. In addition, the primary human hepatocytes were cultured with or without hiPS cells in HSM.

RESULTS

The expression levels of GALK1, GALK2, OTC, and PAH in 201B7 were 22.2±5.0 (average ± standard deviation), 14.2% ±1.1%, 1.2% ±0.2%, and 8.4% ±0.7% respectively, compared with those in the adult liver. The hiPS cell population diminished when cultured in HSM and completely disappeared after 3 days. The cultured cells showed condensation or fragmentation of their nuclei, thereby suggesting apoptosis. TUNEL staining confirmed that the cells had undergone apoptosis. The 201B7 cells were positive for Nanog, SSEA-4, and TRA-1-60. The primary human hepatocytes survived when cultured alone in HSM and when co-cultured with hiPS cells.

CONCLUSION

Therefore, HSM is and ideal medium for eliminating hiPS cells and purifying hepatocytes without inducing any damage.

Transcription Factors and Medium Suitable for Initiating the Differentiation of Human-Induced Pluripotent Stem Cells to the Hepatocyte Lineage

Transcription factors and culture media were investigated to determine the condition to initiate the differentiation of human-induced pluripotent stem (iPS) cells most efficiently. The expression of genes in human adult liver was compared with that in 201B7 cells (iPS cells) using cDNA microarray analysis. Episomal plasmids expressing transcription factors were constructed. 201B7 cells were transfected with the episomal plasmids and cultured in ReproFF (feeder-free media maintaining pluripotency), Leibovitz-15 (L15), William's E (WE), or Dulbecco's modified Eagle medium/Nutrient F-12 Ham (DF12) for 7 days. RNA was isolated and subjected to real-time quantitative PCR to analyze the expression of alpha-feto protein (AFP) and albumin. cDNA microarray analysis revealed 16 transcription factors that were upregulated in human adult liver relative to that in 201B7 cells. Episomal plasmids expressing these 16 genes were transfected into 201B7 cells. CCAAT/enhancer-binding protein alpha (CEBPA), CCAAT/enhancer-binding protein beta (CEBPB), forkhead box A1 (FOXA1), and forkhead box A3 (FOXA3) up-regulated AFP and down-regulated Nanog. These four genes were further analyzed. The expression of AFP and albumin was the highest in 201B7 cells transfected with the combination of CEBPA, CEBPB, FOXA1, and FOXA3 and cultured in WE. The combination of CEBPA, CEBPB, FOXA1, and FOXA3 was suitable for 201B7 cells to initiate differentiation to the hepatocyte lineage and WE was the most suitable medium for culture after transfection. J. Cell. Biochem. 117: 2001-2009, 2016. © 2016 Wiley Periodicals, Inc.

Activin A maintains pluripotency markers and proliferative potential of human induced pluripotent stem cells

To investigate the role of Activin A in the embryoid bodies (EBs) of human induced pluripotent stem (iPS) cells, EBs were transferred onto dishes coated with Matrigel after 4 days of incubation with Activin A and observed under a microscope. Alkaline phosphatase staining and immunostaining were performed to analyze the pluripotency of the cells, and the MTS assay was performed to analyze their proliferative potential. Fourteen days after EB formation, cells cultured with Activin A (100 ng/ml) showed no morphological alterations. Cells cultured with 10-100 ng/ml of Activin A were positive for alkaline phosphatase staining, while cells cultured with 0-3 ng/ml showed negative staining. Cells cultured with 10 ng/ml of Activin A were positive for Oct3/4, Nanog, SSEA-4 and TRA-1-60, while cells cultured with 0 ng/ml Activin A were negative. Cells cultured with 3-30 ng/ml of Activin A maintained their proliferative potential, while loss of proliferative potential was observed in cells cultured with 100 ng/ml Activin A. In conclusion, Activin A maintained pluripotency markers in human iPS cells cultured as EBs with Activin A.

Signaling pathway of insulin-like growth factor-II as a target of molecular therapy for hepatoblastoma

AIM

To address the possibility that insulin-like growth factor (IGF)-II is a growth factor and its signaling pathway so as to develop a molecular therapy for hepatoblastoma.

METHODS

Huh-6 and HepG2, human hepatoblastoma cell lines, were used. IGF-II was added to the medium deprived of serum. Western blot analysis was performed to clarify the expression of IGF-I receptor (IGF-IR). Inhibitors of IGF-IR (piclopodophyllin, PPP), phosphatidyl-inositol (PI) 3-kinase (LY294002 and Wortmannin), or mitogen-activated protein (MAP) kinase (PD98059) were added to unveil the signaling pathway of IGF-II. Cells were analyzed morphologically with hematoxylin-eosin staining to reveal the mechanism of suppression of cell proliferation.

RESULTS

IGF-II stimulated cells proliferated to 2.7 (269%+/-76%) (mean+/-SD) (Huh-6) and 2.1 (211%+/-85%) times (HepG2). IGF-IR was expressed in Huh-6 and HepG2. PPP suppressed the cell number to 44%+/-11% (Huh-6) and 39%+/-5% (HepG2). LY294002 and Wortmannin suppressed the cell number to 30%+/-5% (Huh-6), 44%+/-0.4% (HepG2), 49%+/-1.0% (Huh-6) and 46%+/-1.1% (HepG2), respectively. PD98059 suppressed the cell number to 33%+/-11% for HepG2 but not for Huh-6. When cell proliferation was prohibited, many Huh-6 and HepG2 cells were dead with pyknotic or fragmented nuclei, suggesting apoptosis.

CONCLUSION

IGF-II was shown to be a growth factor of hepatoblastoma via IGF-I receptor and PI3 kinase which were good candidates for target of molecular therapy.

Elevated levels of alanine transaminase and triglycerides within normal limits are associated with fatty liver

In the present study, the threshold values of laboratory data for the diagnosis of non-alcoholic fatty liver disease (NAFLD) were investigated. The study enrolled patients who had undergone abdominal ultrasound (US) between April 2013 and August 2013, and for whom laboratory data were available on the same day. NAFLD was diagnosed following observations of a bright liver or hepatorenal echo contrast on the abdominal US scans. Patients were excluded from the study if they had liver diseases or had been prescribed prednisolone or methotrexate. Receiver operating characteristic curves, the Wilcoxon signed-rank test and Fisher's exact probability test were used for data analysis. In total, 80 NAFLD and 94 non-NAFLD patients were enrolled in the study. The threshold levels of alanine aminotransferase (ALT) and triglyceride (TG) for the diagnosis of NAFLD were 19.0 IU/l and 101 mg/dl, respectively. Patients were divided into two groups according to the levels of ALT and TG. Those with ALT levels of >19 IU/l and TG levels of >101 mg/dl were defined as the positive group, while the remaining patients were classified as the negative group. The specificity and positive predictive value using the combined threshold levels of ALT >19 IU/l and TG >101 mg/dl were 80.9 and 75.0%, respectively. Therefore, the results indicated that ALT levels of >19 IU/l or TG levels of >101 mg/dl were useful markers for the screening of NAFLD. However, NAFLD was more strongly suspected in patients with ALT levels of >19 IU/l and TG levels of >101 mg/dl.

Laboratory test variables useful for distinguishing upper from lower gastrointestinal bleeding

AIM

To distinguish upper from lower gastrointestinal (GI) bleeding.

METHODS

Patient records between April 2011 and March 2014 were analyzed retrospectively (3296 upper endoscopy, and 1520 colonoscopy). Seventy-six patients had upper GI bleeding (Upper group) and 65 had lower GI bleeding (Lower group). Variables were compared between the groups using one-way analysis of variance. Logistic regression was performed to identify variables significantly associated with the diagnosis of upper vs lower GI bleeding. Receiver-operator characteristic (ROC) analysis was performed to determine the threshold value that could distinguish upper from lower GI bleeding.

RESULTS

Hemoglobin (P = 0.023), total protein (P = 0.0002), and lactate dehydrogenase (P = 0.009) were significantly lower in the Upper group than in the Lower group. Blood urea nitrogen (BUN) was higher in the Upper group than in the Lower group (P = 0.0065). Logistic regression analysis revealed that BUN was most strongly associated with the diagnosis of upper vs lower GI bleeding. ROC analysis revealed a threshold BUN value of 21.0 mg/dL, with a specificity of 93.0%.

CONCLUSION

The threshold BUN value for distinguishing upper from lower GI bleeding was 21.0 mg/dL.

Single-step protocol for the differentiation of human-induced pluripotent stem cells into hepatic progenitor-like cells

Induced pluripotent stem (iPS) cells are ideal sources of hepatocyte for transplantation into patients experiencing hepatic failure. Growth and transcription factors were analyzed to design a single-step protocol for the differentiation of iPS cells into hepatocytes. The expression of transcription factors was analyzed using reverse transcription-polymerase chain reaction (RT-PCR) and compared among iPS cells, as well as fetal and adult liver cells. iPS cells were cultured with growth factors and RT-PCR was performed to analyze the expression of transcription factors. iPS cells were introduced with transcription factors, cultured with growth factors and subjected to real-time quantitative PCR. Indocyanine green (ICG) was added to the medium as a hepatocyte marker. Sox17, GATA4, GATA6, FoxA2, HEX, HNF4α and C/EBPα were expressed in fetal and adult liver cells, but not in iPS cells. Sox17, GATA6 and HNF4α were expressed after exposure a combination of oncostatin M, epidermal growth factor, retinoic acid, dexamethasone and ITS (OERDITS). When iPS cells were introduced with FoxA2, GATA4, HEX and C/EBPα and cultured with OERDITS for 8 days, the cells expressed α-fetoprotein, δ-like (Dlk)-1 and γ-glutamyl transpeptidase (GTP), and ICG uptake was observed. Exposure to FoxA2, GATA4, HEX and C/EBPα and culturing with OERDITS supplementation potentially serves as a single-step inducer for the differentiation of iPS cells into hepatic progenitor-like cells within 8 days.

An Optimal Medium Supplementation Regimen for Initiation of Hepatocyte Differentiation in Human Induced Pluripotent Stem Cells

Human induced pluripotent stem (hiPS) cells are an ideal source for hepatocytes. Glucose and arginine are necessary for cells to survive. Hepatocytes have galactokinase (GALK), which metabolizes galactose for gluconeogenesis, and ornithine transcarbamylase (OTC), which converts ornithine to arginine in the urea cycle. Hepatocyte selection medium (HSM) lacks both glucose and arginine, but contains galactose and ornithine. Although human primary hepatocytes survive in HSM, all the hiPS cells die in 3 days. The aim of this study was to modify HSM so as to initiate hepatocyte differentiation in hiPS cells within 2 days. Hepatocyte differentiation initiating medium (HDI) was prepared by adding oncostatin M (10 ng/ml), hepatocyte functional proliferation inducer (10 nM), 2,2'-methylenebis (1,3-cyclohexanedione) (M50054) (100 μg/ml), 1× non-essential amino acid, 1× sodium pyruvate, nicotinamide (1.2 mg/ml), L-proline (30 ng/ml), and L-glutamine (0.3 mg/ml) to HSM. HiPS cells (201B7 cells) were cultured in HDI for 2 days. RNA was isolated, used as template for cDNA, and subjected to real-time quantitative polymerase chain reaction. Alpha-fetoprotein, γ-glutamyl transpeptidase, and delta-like 1 were upregulated. Expression of albumin was not observed. Expression of transcription factors specific to hepatocytes was upregulated. The expression of GALK2, OTC, and CYP3A4 were increased. In conclusion, differentiation of 201B7 cells to hepatoblast-like cells was initiated in HDI. Limitations were small number of cells were obtained, and the cells with HDI were not mature hepatocytes.

Sorafenib suppresses the cell cycle and induces the apoptosis of hepatocellular carcinoma cell lines in serum-free media

To suppress the invasion of hepatocellular carcinoma (HCC) cells into surrounding connective tissues during metastasis, we investigated the usefulness of sorafenib. In order to search for model cell lines, cell numbers were counted to reveal cell lines with the potential to proliferate in serum-free media. Cell proliferation and cell motility were analyzed with the MTS and wound assay, respectively. 5-Bromo-2'-deoxyuridine (BrdU) labeling and mitotic and apoptotic indices were analyzed to assess the cell cycle and apoptosis. The expression levels of cyclin D1 and the cleavage of caspase-3 were analyzed by Western blotting. HLF cells exhibited growth in the serum-free medium, while the other cell lines examined did not. Sorafenib suppressed the cell proliferation and motility of the HLF cells in the serum-free media. Both indices of BrdU and mitotic potential decreased and the apoptotic index was increased in the serum-free media with sorafenib, suggesting that the cell cycle was suppressed and apoptosis was induced. The expression levels of cyclin D1 decreased and the cleavage of caspase-3 was noted in the serum-free media with sorafenib. Sorafenib may be suitable for molecular therapy to suppress the metastasis of HCC.

Anti-mitochondrial M2 antibody-positive autoimmune hepatitis

Anti-mitochondrial M2 antibody (AMA-M2) is specific to primary biliary cirrhosis (PBC), but can also be found in certain patients with autoimmune hepatitis (AIH). Effective methods of differentiating between PBC and AIH are required, as their clinical course and management are different. Titers of AMA-M2 were analyzed before and after follow-up in patients with PBC or AIH. Patients who underwent liver biopsy and were diagnosed with either AIH (10 patients) or PBC (3 patients) were enrolled in the study. The AMA-M2 antibody titers of these patients were analyzed upon hospital admission. AMA-M2 reacted with the pyruvate dehydrogenase complex-E2, branched-chain 2-oxo acid dehydrogenase complex and 2-oxoglutaric acid dehydrogenase complex in the assay utilized for this study. The cut-off value for AMA-M2 was 5. Six AIH patients were AMA-M2(-) and 4 were AMA-M2(+). The titer for the AIH patients who were AMA-M2(+) was 24.8±14.8, compared with 324±174 in the patients with PBC (P=0.0138). Three AMA-M2(+) AIH patients were followed-up after liver biopsy. The AMA-M2 levels had decreased in all 3 patients, becoming undetectable in 2 of them. In conclusion, certain patients with AIH in this study were found to be AMA-M2(+), but the titers were significantly lower than those in the patients with PBC. At follow-up, the AIH patients exhibited decreased AMA-M2 titers.

Gastric cancer cell proliferation is suppressed by frizzled-2 short hairpin RNA

In order to identify novel targets for the molecular therapy of gastric cancer (GC), we investigated the mRNA and protein expression of frizzled-2 (Fz2), a Wnt signaling pathway receptor. Reverse-transcriptase polymerase chain reaction (PCR) amplification was utilized to determine the expression patterns of Fz genes in normal stomach and in the GC cell lines MKN45 and MKN74. Immunostaining was performed on surgical specimens of GC using an antibody against Fz2. The 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2- (4-sulfophenyl)-2H-tetrazolium inner salt (MTS) assay was performed on MKN45 cells and MKN74 cells transfected with Fz2 short-hairpin (sh) RNA. Cell motility was analyzed by scratch assay following Fz2 shRNA. Real-time quantitative PCR was performed to analyze the expression levels of cyclin D1 and matrix metallopeptidase 9 (MMP-9). Fz1, 3, 6 and 8 were expressed in normal stomach, and in MKN45 and MKN74 cells. Fz2 was expressed in normal stomach and in MKN45, but not in MKN74 cells. Well-differentiated GC tissue was weakly positive for Fz2 in cell membranes. Fz2 was positive in both the cell membrane and cytoplasm of GC tissues of moderately differentiated and poorly differentiated adenocarcinoma. Signet ring cells were positive for cytoplasmic Fz2. Proliferation of MKN45 and MKN74 cells was suppressed by Fz2 shRNA, and a scratch assay demonstrated that Fz2 shRNA suppressed also MKN45 and MKN74 cell motility. Furthermore, Fz2 shRNA application led to downregulated mRNA expression of both cyclin D1 and MMP-9. Fz2, 3, 6 and 8 were expressed in normal stomach, and in MKN45 and MKN74 GC cells. Fz2 shRNA suppressed cell proliferation and motility of MKN45 and MKN74 cells, and downregulated cyclin D1 and MMP-9 expression in these GC cell lines.

Insulin-like growth factor (IGF)-II regulates CCAAT/enhancer binding protein alpha expression via phosphatidyl-inositol 3 kinase in human hepatoblastoma cell lines

To reveal growth factor and its signal pathway to CCAAT/enhancer binding protein alpha (C/EBPalpha) in hepatocyte differentiation, we used Huh-6 and HepG2, human hepatoblastoma (HBL) cell lines that maintain the expression of genes in hepatoblasts and remain at that stage of differentiation. Insulin-like growth factor (IGF)-II, hepatocyte growth factor (HGF), and dexamethasone (Dex) stimulated HBL cells for Northern blot analysis. Bromodeoxyuridine (BrdU) up-take assay and Western blot analysis on albumin was performed to unveil proliferation and differentiation activity of IGF-II. C/EBPalpha and phosphorylation of Akt were analyzed by Western blot analysis. LY294002 and wortmannin, specific inhibitors of PI3 kinase, and PD98059, a specific inhibitor of mitogen-activated protein (MAP) kinase, were used to examine the signaling pathway of C/EBPalpha upregulated by IGF-II. Luciferase assay was performed to study the promoter activity of C/EBPalpha. Actinomycin D was used to analyze half-life of C/EBPalpha mRNA. IGF-II up-regualted C/EBPalpha by Northern blot and Western blot while HGF and Dex did not by Northern blot. IGF-II promoted proliferation and differentiation by BrdU up-take assay and Western blot analysis on albumin. Akt phosphorylated by IGF-II, suggested that phosphatidyl-inositol (PI) 3 kinase mediated the signaling pathway of IGF-II. LY294002 and wortmannin suppressed expression of C/EBPalpha. IGF-II activated the promoter activity and prolonged half-life of mRNA, suggesting that IGF-II activated promoter and stabilized mRNA. LY294002 and wortmannin suppressed the promoter activity of C/EBPalpha while PD98059 did not, suggesting that activation of the promoter was mediated by PI3 kinase.