Baicalein inhibits the migration and invasive properties of human hepatoma cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chiu, Yung-Wei; Institute of Medicine, Chung Shan Medical University, Taiwan; Lin, Tseng-Hsi

Flavonoids have been demonstrated to exert health benefits in humans. We investigated whether the flavonoid baicalein would inhibit the adhesion, migration, invasion, and growth of human hepatoma cell lines, and we also investigated its mechanism of action. The separate effects of baicalein and baicalin on the viability of HA22T/VGH and SK-Hep1 cells were investigated for 24 h. To evaluate their invasive properties, cells were incubated on matrigel-coated transwell membranes in the presence or absence of baicalein. We examined the effect of baicalein on the adhesion of cells, on the activation of matrix metalloproteinases (MMPs), protein kinase C (PKC), and p38more » mitogen-activated protein kinase (MAPK), and on tumor growth in vivo. We observed that baicalein suppresses hepatoma cell growth by 55%, baicalein-treated cells showed lower levels of migration than untreated cells, and cell invasion was significantly reduced to 28%. Incubation of hepatoma cells with baicalein also significantly inhibited cell adhesion to matrigel, collagen I, and gelatin-coated substrate. Baicalein also decreased the gelatinolytic activities of the matrix metalloproteinases MMP-2, MMP-9, and uPA, decreased p50 and p65 nuclear translocation, and decreased phosphorylated I-kappa-B (IKB)-{beta}. In addition, baicalein reduced the phosphorylation levels of PKC{alpha} and p38 proteins, which regulate invasion in poorly differentiated hepatoma cells. Finally, when SK-Hep1 cells were grown as xenografts in nude mice, intraperitoneal (i.p.) injection of baicalein induced a significant dose-dependent decrease in tumor growth. These results demonstrate the anticancer properties of baicalein, which include the inhibition of adhesion, invasion, migration, and proliferation of human hepatoma cells in vivo. - Highlight: > Baicalein inhibits several essential steps in the onset of metastasis.« less

Peroxisome proliferators induce apoptosis in hepatoma cells.

PubMed

Canuto, R A; Muzio, G; Bonelli, G; Maggiora, M; Autelli, R; Barbiero, G; Costelli, P; Brossa, O; Baccino, F M

1998-01-01

In the AH-130 hepatoma, a poorly differentiated tumor, maintained by weekly transplantations in rats, a low percentage of cells spontaneously underwent apoptosis, mainly during the transition from logarithmic- to stationary-growth phase. It was possible to induce massive apoptosis of cells by treating them with clofibrate, a peroxisome proliferator and hypolipidemic drug. Similar results were obtained with HepG2 cells. With 1 mM clofibrate, apoptosis began to manifest itself after 1 h of treatment in vitro, and was assessed by morphological analysis, by DNA fragmentation carried out with agarose gel electrophoresis, and with flow cytometric determination of terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling. The mechanisms whereby clofibrate induces apoptosis are still unclear. Since the peroxisome proliferator-activated receptor was expressed at a very low level and was not stimulated by clofibrate in the AH-130 hepatoma cells, its involvement seems unlikely. Moreover, lipid peroxidation was not increased after clofibrate treatment. Phospholipids and cholesterol were significantly decreased. The decreased cholesterol content might suggest an inhibition of the mevalonate pathway and, therefore, of isoprenylation of proteins involved in cell proliferation.

INHIBITORY EFFECT OF CHITOSAN OLIGOSACCHARIDE ON HUMAN HEPATOMA CELLS IN VITRO.

PubMed

Liu, Likun; Xin, Yi; Liu, Jia; Zhang, Ershao; Li, Weiling

2017-01-01

Chitosan oligosaccharide, the degradation products of chitin, was reported to have a wide range of physiological functions and biological activities. In this study, we explored the inhibitory effect of Chitosan oligosaccharide on human hepatoma cells. MTT assay was applied to detect cell viability of the human hepatoma cells treated with Chitosan oligosaccharide. Flow cytometric analysis was used to investigate the apoptosis of the human hepatoma cells treated with Chitosan oligosaccharide. We employed western blot to investigate the underlying mechanisms involved in the apoptosis. Our data indicated that chitosan oligosaccharide dose-dependently inhibited the growth of hepatoma cells and induced apoptosis. On the molecular level, chitosan oligosaccharide decreased Bcl-2 and increased Caspase-3 expression which may be related to the apoptosis of hepatoma cells. Our results provide an experimental basis for the clinical development of Chitosan oligosaccharide as a novel anti-hepatoma drug.

Liver-enriched transcription factors uncoupled from expression of hepatic functions in hepatoma cell lines.

PubMed Central

Chaya, D; Fougère-Deschatrette, C; Weiss, M C

1997-01-01

Among the liver-enriched transcription factors identified to date, only expression of hepatocyte nuclear factor 4 (HNF4) and hepatocyte nuclear factor 1 (HNF1) is in strict correlation with hepatic differentiation in cultured rat hepatoma cells. Indeed, differentiated hepatoma cells that stably express an extensive set of adult hepatic functions express liver-enriched transcription factors, while dedifferentiated cells that have lost expression of all these hepatic functions no longer express HNF4 and HNF1. We describe a new heritable phenotype, designated as uncoupled, in which there is a spontaneous dissociation between the expression of these transcription factors and that of the hepatic functions. Cells presenting this phenotype, isolated from differentiated hepatoma cells, cease to accumulate all transcripts coding for hepatic functions but nevertheless maintain expression of HNF4 and HNF1. Transitory transfection experiments indicate that these two factors present in these cells have transcriptional activity similar to that of differentiated hepatoma cells. Characterization of the appropriate intertypic cell hybrids demonstrates that this new phenotype is recessive to the dedifferentiated state and fails to be complemented by differentiated cells. These results indicate the existence of mechanisms that inhibit transcription of genes coding for hepatocyte functions in spite of the presence of functional HNF4 and HNF1. Cells of the uncoupled phenotype present certain properties of oval cells described for pathological states of the liver. PMID:9343392

Liver-enriched transcription factors uncoupled from expression of hepatic functions in hepatoma cell lines.

PubMed

Chaya, D; Fougère-Deschatrette, C; Weiss, M C

1997-11-01

Among the liver-enriched transcription factors identified to date, only expression of hepatocyte nuclear factor 4 (HNF4) and hepatocyte nuclear factor 1 (HNF1) is in strict correlation with hepatic differentiation in cultured rat hepatoma cells. Indeed, differentiated hepatoma cells that stably express an extensive set of adult hepatic functions express liver-enriched transcription factors, while dedifferentiated cells that have lost expression of all these hepatic functions no longer express HNF4 and HNF1. We describe a new heritable phenotype, designated as uncoupled, in which there is a spontaneous dissociation between the expression of these transcription factors and that of the hepatic functions. Cells presenting this phenotype, isolated from differentiated hepatoma cells, cease to accumulate all transcripts coding for hepatic functions but nevertheless maintain expression of HNF4 and HNF1. Transitory transfection experiments indicate that these two factors present in these cells have transcriptional activity similar to that of differentiated hepatoma cells. Characterization of the appropriate intertypic cell hybrids demonstrates that this new phenotype is recessive to the dedifferentiated state and fails to be complemented by differentiated cells. These results indicate the existence of mechanisms that inhibit transcription of genes coding for hepatocyte functions in spite of the presence of functional HNF4 and HNF1. Cells of the uncoupled phenotype present certain properties of oval cells described for pathological states of the liver.

INHIBITORY EFFECT OF CHITOSAN OLIGOSACCHARIDE ON HUMAN HEPATOMA CELLS IN VITRO

PubMed Central

Liu, Likun; Xin, Yi; Liu, Jia; Zhang, Ershao; Li, Weiling

2017-01-01

Background: Chitosan oligosaccharide, the degradation products of chitin, was reported to have a wide range of physiological functions and biological activities. In this study, we explored the inhibitory effect of Chitosan oligosaccharide on human hepatoma cells Materials and Methods: MTT assay was applied to detect cell viability of the human hepatoma cells treated with Chitosan oligosaccharide. Flow cytometric analysis was used to investigate the apoptosis of the human hepatoma cells treated with Chitosan oligosaccharide. We employed western blot to investigate the underlying mechanisms involved in the apoptosis. Results: Our data indicated that chitosan oligosaccharide dose-dependently inhibited the growth of hepatoma cells and induced apoptosis. On the molecular level, chitosan oligosaccharide decreased Bcl-2 and increased Caspase-3 expression which may be related to the apoptosis of hepatoma cells. Conclusion: Our results provide an experimental basis for the clinical development of Chitosan oligosaccharide as a novel anti-hepatoma drug. PMID:28638890

Cell death induced by Morarah and Khaltita in hepatoma cancer cells (Huh-7).

PubMed

Baig, Saeeda; Alamgir, Mohiuddin

2009-10-01

To compare the combined and isolated growth inhibitory effects of Morarah and Khaltita (herbs) on hepatoma cell lines (Huh-7), through induction of apoptosis or necrosis. Comparative controlled in-vitro study. The Molecular Biology Laboratory, The Aga Khan University, Karachi, from June to December 2006. The growth of hepatoma cell lines (Huh-7) was checked by adding Khaltita and Morarah to the cells before culture in a 24 well plate. Six wells were selected and labeled for each of the four variables (controls, Khaltita, Morarah and mixture). After 2 days, cells were studied under an inverted phase contrast microscope and fields were recorded. Approximately four fields per slide of higher intensity were selected randomly to determine the dead cell density, and the procedure was repeated 10 or more times. Frequency and percentages were calculated for dead or alive cells in controls, Morarah, Khaltita and their mixture. Chi-square was used to compare the qualitative variables. P-values < 0.05 were considered significant. Morarah and Khaltita were found to induce statistically significant (p < 0.001) cell death in hepatoma cell lines (Huh-7). At a magnification of 40x, the controls showed 1% dead cells compared to 91% in Morarah, 83% in Khaltita and 73% in combined mixture of Khaltita and Morarah. At magnification of 20x, the controls showed 4% dead cells compared to 44% in Morarah, 47% in Khaltita and 49% in the combined mixture of Khaltita and Morarah. Morarah and Khaltita induced cell death in cultured hepatoma cells (Huh-7).

Novel role of TRPV2 in promoting the cytotoxicity of H2O2-mediated oxidative stress in human hepatoma cells.

PubMed

Ma, Wenbo; Li, Caiyue; Yin, Shikui; Liu, Jingxin; Gao, Chao; Lin, Zuoxian; Huang, Rongqi; Huang, Jufang; Li, Zhiyuan

2015-12-01

Oxidative stress is important for the initiation and progression of cancers, which confers the cells with a survival advantage by inducing oxidative adaption and drug resistance. Therefore, developing strategies to promote oxidative stress-induced cytotoxicity could be important for cancer therapy. Herein, we found that H2O2-mediated oxidative stress increases TRPV2 expression in human hepatoma (HepG2 and Huh-7) cells. This occurred at the mRNA and protein levels in a dose-dependent manner. The significance of TRPV2 in promoting H2O2-induced cell death was demonstrated in gain and loss of function studies with overexpression and knockdown of TRPV2, respectively. Mechanistically, H2O2-induced cell death involves inhibition of pro-survival signaling proteins (Akt, Nrf2) and activation of pro-death signaling proteins (p38, JNK1). Overexpression of TRPV2 in H2O2-treated hepatoma cells aggravates the inhibition of Akt and Nrf2, while it enhances the activation of p38 and JNK1 at the early stage of cell death. Interestingly, increased expression of TRPV2 in HepG2 cells improved the efficacy of stress-associated chemicals to induce cell death. Our findings suggest that TRPV2 acts as an important enhancer for H2O2-induced cytotoxicity. This process occurred by the inhibition of Akt and Nrf2 as well as the early activation of p38 and JNK1. These findings have important implications for inhibition of oxidative adaption and drug resistance. Copyright © 2015 Elsevier Inc. All rights reserved.

Anti-hepatoma activity of a novel compound glaucocalyxin H in vivo and in vitro.

PubMed

Hai, Guangfan; Zhang, Chong; Jia, Yanlong; Bai, Suping; Han, Jinfen; Guo, Lanqing; Cui, Taizhen; Niu, Bingxuan; Huang, Feng; Song, Yu

2015-06-01

Glaucocalyxin H (GLH) is a new compound isolated from a traditional Chinese medical herb Isodon japonica var. glaucocalyx which has been used for folk medicine. This study was carried out for the first time to investigate the potential role of GLH in anti-hepatoma activity and underlying mechanisms in it. GLH could inhibit the growth of tumor in mice and induce HepG2 cells to death as assessed by the tumor reduction assay, toxic assay, morphological change, and survival rate assay. Many antitumor drugs originated from plants could inhibit the growth of tumor by inducing cells to apoptosis. The morphological changes of HepG2 cells treated with different concentrations of GLH under fluorescence and electron microscope and apoptotic rates were detected to verify its effect on apoptosis. As shown in the study, GLH could induce HepG2 cells to apoptosis in a dose-dependent manner. Bcl2 and Bax proteins played important roles in apoptosis and the disequilibrium between Bcl2 and Bax might result in apoptosis. The expression of Bax protein was upregulated and Bcl2 protein was downregulated in HepG2 cells treated with GLH assessed by Western blotting, and they were in a dose-dependent manner. Taken together, GLH can inhibit the growth of hepatoma cells in vivo and in vitro by inducing cell apoptosis due to the decreased Bcl2 and increased Bax proteins suggesting that GLH could be a potential candidate as an anti-hepatoma agent for the therapeutic treatment of hepatoma.

Comparative Study of Light Scattering from Hepatoma Cells and Hepatocytes

NASA Astrophysics Data System (ADS)

Lin, Xiaogang; Wang, Rongrong; Guo, Yongcai; Gao, Chao; Guo, Xiaoen

2012-11-01

Primary liver cancer is one of the highest mortality malignant tumors in the world. China is a high occurrence area of primary liver cancer. Diagnosis of liver cancer, especially early diagnosis, is essential for improving patients' survival. Light scattering and measuring method is an emerging technology developed in recent decades, which has attracted a large number of biomedical researchers due to its advantages, such as fast, simple, high accuracy, good repeatability, and non-destructive. The hypothesis of this project is that there may be some different light scattering information between hepatoma cells and hepatocyte. Combined with the advantages of the dynamic light scattering method and the biological cytology, an experimental scheme to measure the light scattering information of cells was formulated. Hepatoma cells and hepatic cells were irradiated by a semiconductor laser (532 nm). And the Brookhaven BI-200SM wide-angle light scattering device and temperature control apparatus were adopted. The light scattering information of hepatoma cells and hepatic cells in vitro within the 15°C to 30°C temperature range was processed by a BI-9000AT digital autocorrelator. The following points were found: (a) the scattering intensities of human hepatic cells and hepatoma cells are nearly not affected by the temperature factor, and the former is always greater than the latter and (b) the relaxation time of hepatoma cells is longer than that of hepatic cells, and both the relaxation time are shortened with increasing temperature from 15°C to 25°C. It can be concluded that hepatoma cells could absorb more incident light than hepatic cells. The reason may be that there exists more protein and nucleic acid in cancerous cells than normal cells. Furthermore, based on the length relaxation time, a conclusion can be inferred that the Brownian movement of cancer cells is greater.

Effects of a fish oil-based emulsion on rat hepatoma cell invasion in culture.

PubMed

Hagi, Akifumi; Nakayama, Mitsuo; Miura, Yutaka; Yagasaki, Kazumi

2007-01-01

Total parenteral nutrition containing a lipid emulsion is often employed after surgical tumor resection. This study investigated the effects of a fish oil-based infusion on rat hepatoma cell invasion. Rat ascites hepatoma cell line AH109A was precultured with a fish oil-based or safflower oil-based emulsion for 48 h. Changes in membranous fatty acid composition were evaluated by gas chromatography. The invasiveness of hepatoma cells was assessed by coculturing with mesentery-derived mesothelial cells. To examine ex vivo effects of the fish oil-based infusion on hepatoma invasion, sera were prepared from rats infused with fish oil- or safflower oil-based emulsion and the effects of these sera were assessed. To clarify the mechanism of inhibition of invasion by the fish oil-based emulsion, the effects of prostaglandin (PG) E(2) and PGE(3) on invasion were examined. Pretreatment with the fish oil-based emulsion reduced invasiveness without affecting growth compared with the safflower oil-based emulsion. Pretreatment with the sera from rats infused with the fish oil-based emulsion also reduced invasiveness compared with the sera from rats infused with the safflower oil-based emulsion. The addition of PGE(2) eliminated the inhibitory effect of the fish oil-based emulsion, and the addition of PGE(3) reduced the invasiveness of hepatoma cells pretreated with the safflower oil-based emulsion. These results suggest that the fish oil-based emulsion may have anti-invasive effects. Changes in the membranous fatty acid composition and consequent changes in the prostaglandins produced may be involved in this inhibitory effect.

Epigenetic Targeting of Granulin in Hepatoma Cells by Synthetic CRISPR dCas9 Epi-suppressors.

PubMed

Wang, Hong; Guo, Rui; Du, Zhonghua; Bai, Ling; Li, Lingyu; Cui, Jiuwei; Li, Wei; Hoffman, Andrew R; Hu, Ji-Fan

2018-06-01

The CRISPR-associated Cas9 system can modulate disease-causing alleles both in vivo and ex vivo, raising the possibility of therapeutic genome editing. In addition to gene targeting, epigenetic modulation by the catalytically inactive dCas9 may also be a potential form of cancer therapy. Granulin (GRN), a potent pluripotent mitogen and growth factor that promotes cancer progression by maintaining self-renewal of hepatic stem cancer cells, is upregulated in hepatoma tissues and is associated with decreased tumor survival in patients with hepatoma. We synthesized a group of dCas9 epi-suppressors to target GRN by tethering the C terminus of dCas9 with three epigenetic suppressor genes: DNMT3a (DNA methyltransferase), EZH2 (histone 3 lysine 27 methyltransferase), and KRAB (the Krüppel-associated box transcriptional repression domain). In conjunction with guide RNAs (gRNAs), the dCas9 epi-suppressors caused significant decreases in GRN mRNA abundance in Hep3B hepatoma cells. These dCas9 epi-suppressors initiated de novo CpG DNA methylation in the GRN promoter, and they produced histone codes that favor gene suppression, including decreased H3K4 methylation, increased H3K9 methylation, and enhanced HP1a binding. Epigenetic knockdown of GRN led to the inhibition of cell proliferation, decreased tumor sphere formation, and reduced cell invasion. These changes were achieved at least partially through the MMP/TIMP pathway. This study thus demonstrates the potential utility of using dCas9 epi-suppressors in the development of epigenetic targeting against tumors. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Co-operation of the transcription factor hepatocyte nuclear factor-4 with Sp1 or Sp3 leads to transcriptional activation of the human haem oxygenase-1 gene promoter in a hepatoma cell line.

PubMed Central

Takahashi, Shigeru; Matsuura, Naomi; Kurokawa, Takako; Takahashi, Yuji; Miura, Takashi

2002-01-01

We reported previously that the 5'-flanking region (nucleotides -1976 to -1655) of the human haem oxygenase-1 ( hHO-1 ) gene enhances hHO-1 promoter activity in human hepatoma HepG2 cells, but not in HeLa cells [Takahashi, Takahashi, Ito, Nagano, Shibahara and Miura (1999) Biochim. Biophys. Acta 1447, 231-235]. To define more precisely the regulatory elements involved, in the present study we have functionally dissected this region and localized the enhancer to a 50 bp fragment (-1793 to -1744). Site-direct mutagenesis analysis revealed that two regions were responsible for this enhancer activity, i.e. a hepatocyte nuclear factor-4 (HNF-4) homologous region and a GC box motif homologous region. Mutation in either region alone moderately decreased enhancer activity. However, mutations in both regions reduced promoter activity to the basal level. Electrophoretic mobility-shift assays demonstrated that the P5-2 fragment (-1793 to -1744) interacted with at least two nuclear factors, i.e. HNF-4 and Sp1/Sp3. Co-transfection experiments using Drosophila SL2 cells revealed that HNF-4 and Sp1/Sp3 synergistically stimulated the enhancer activity of the P5-2 fragment. These results indicate that co-operation of HNF-4 with Sp1 or Sp3 leads to the activation of hHO-1 gene expression in hepatoma cells. PMID:12133007

Co-operation of the transcription factor hepatocyte nuclear factor-4 with Sp1 or Sp3 leads to transcriptional activation of the human haem oxygenase-1 gene promoter in a hepatoma cell line.

PubMed

Takahashi, Shigeru; Matsuura, Naomi; Kurokawa, Takako; Takahashi, Yuji; Miura, Takashi

2002-11-01

We reported previously that the 5'-flanking region (nucleotides -1976 to -1655) of the human haem oxygenase-1 ( hHO-1 ) gene enhances hHO-1 promoter activity in human hepatoma HepG2 cells, but not in HeLa cells [Takahashi, Takahashi, Ito, Nagano, Shibahara and Miura (1999) Biochim. Biophys. Acta 1447, 231-235]. To define more precisely the regulatory elements involved, in the present study we have functionally dissected this region and localized the enhancer to a 50 bp fragment (-1793 to -1744). Site-direct mutagenesis analysis revealed that two regions were responsible for this enhancer activity, i.e. a hepatocyte nuclear factor-4 (HNF-4) homologous region and a GC box motif homologous region. Mutation in either region alone moderately decreased enhancer activity. However, mutations in both regions reduced promoter activity to the basal level. Electrophoretic mobility-shift assays demonstrated that the P5-2 fragment (-1793 to -1744) interacted with at least two nuclear factors, i.e. HNF-4 and Sp1/Sp3. Co-transfection experiments using Drosophila SL2 cells revealed that HNF-4 and Sp1/Sp3 synergistically stimulated the enhancer activity of the P5-2 fragment. These results indicate that co-operation of HNF-4 with Sp1 or Sp3 leads to the activation of hHO-1 gene expression in hepatoma cells.

Inhibition of Hepatitis B Virus and Induction of Hepatoma Cell Apoptosis by ASGPR-Directed Delivery of shRNAs

PubMed Central

Yao, Xinxin; Shi, Chuan; Sun, Lifang; Yuan, Lu; Lei, Ping; Zhu, Huifen; Liu, Hongbo; Wu, Xiongwen; Ning, Qin; Zhou, Chun; Shen, Guanxin

2012-01-01

Hepatitis B virus (HBV) infection is a worldwide liver disease and nearly 25% of chronic HBV infections terminate in hepatocellular carcinoma (HCC). Currently, there is no effective therapy to inhibit HBV replication and to eliminate hepatoma cells, making it highly desired to develop novel therapies for these two stages of the HBV-caused detrimental disease. Recently, short hairpin RNA (shRNA) has emerged as a potential therapy for virus-infected disease and cancer. Here, we have generated a shRNA, pGenesil-siHBV4, which effectively inhibits HBV replication in the human hepatoma cell line HepG2.2.15. The inhibitory effects of pGenesil-siHBV4 are manifested by the decrease of both the HBV mRNA level and the protein levels of the secreted HBV surface antigen (HBsAg) and HBV e antigen (HBeAg), and by the reduction of secreted HBV DNA. Using mouse hydrodynamic tail vein injection, we demonstrate that pGenesil-siHBV4 is effective in inhibiting HBV replication in vivo. Because survivin plays a key role in cancer cell escape from apoptosis, we further generated pGenesil-siSurvivin, a survivin-silencing shRNA, and showed its effect of triggering apoptosis of HBV-containing hepatoma cells. To develop targeted shRNA therapy, we have identified that as a specific binder of the asialoglycoprotein receptor (ASGPR), jetPEI-Hepatocyte delivers pGenesil-siHBV4 and pGenesil-siSurvivin specifically to hepatocytes, not other types of cells. Finally, co-transfection of pGenesil-siHBV4 and pGenesil-siSurvivin exerts synergistic effects in inducing hepatoma cell apoptosis, a novel approach to eliminate hepatoma by downregulating survivin via multiple mechanisms. The application of these novel shRNAs with the jetPEI-Hepatocyte targeting strategy demonstrates the proof-of-principle for a promising approach to inhibit HBV replication and eliminate hepatoma cells with high specificity. PMID:23094023

Localization of nuclear subunits of cyclic AMP-dependent protein kinase by the immunocolloidal gold method

PubMed Central

1985-01-01

An immunocolloidal gold electron microscopy method is described allowing the ultrastructural localization and quantitation of the regulatory subunits RI and RII and the catalytic subunit C of cAMP- dependent protein kinase. Using a postembedding indirect immunogold labeling procedure that employs specific antisera, the catalytic and regulatory subunits were localized in electron-dense regions of the nucleus and in cytoplasmic areas with a minimum of nonspecific staining. Antigenic domains were localized in regions of the heterochromatin, nucleolus, interchromatin granules, and in the endoplasmic reticulum of different cell types, such as rat hepatocytes, ovarian granulosa cells, and spermatogonia, as well as cultured H4IIE hepatoma cells. Morphometric quantitation of the relative staining density of nuclear antigens indicated a marked modulation of the number of subunits per unit area under various physiologic conditions. For instance, following partial hepatectomy in rats, the staining density of the nuclear RI and C subunits was markedly increased 16 h after surgery. Glucagon treatment of rats increased the staining density of only the nuclear catalytic subunit. Dibutyryl cAMP treatment of H4IIE hepatoma cells led to a marked increase in the nuclear staining density of all three subunits of cAMP-dependent protein kinase. These studies demonstrate that specific antisera against cAMP-dependent protein kinase subunits may be used in combination with immunogold electron microscopy to identify the ultrastructural location of the subunits and to provide a semi-quantitative estimate of their relative cellular density. PMID:2993318

[IL-12 induces autophagy via AKT/mTOR/STAT3 signaling pathway in human hepatoma cells].

PubMed

Liu, Cuiying; Xie, Changli; Lin, Yan; Wu, Bitao; Wang, Qin; Li, Ziwei; Tu, Zhiguang

2016-07-01

Objective To investigate the effect of IL-12 on autophagy and the relative possible mechanism in HepG2 and SMMC-7721 human hepatoma cells. Methods The hepatoma cells were treated with IL-12 (10 ng/mL) for 6 hours. Western blotting was applied to detect the expressions of microtubule-associated protein 1 light chain 3 (LC-3), Beclin 1 and the phosphorylated levels of protein kinase B (AKT), mammalian target of rapamycin (mTOR), signal transducer and activator of transcription 3 (STAT3); immunofluorescence assay (IFA) and transmission electron microscopy (TEM) were used to observe the formation of autophagosome. After STAT3 was inhibited by STATTIC or siSTAT3 and AKT was activated by insulin-like growth factor (IGF-1), Western blotting and IFA were performed again to analyze the change of IL-12-induced autophagy. After the cells were treated with IL-12 (10 ng/mL) for 1, 2, 3, 4, 5 days, CCK-8 assay was used to determine the growth ability. After the hepatoma cells were treated with IL-12 (10 ng/mL) for 48 hours, trypan blue staining was used to detect the death rate of the cells. After cell autophagy was inhibit by siBeclin 1, CCK-8 assay and trypan blue staining were performed again to study the effect of IL-12 on the proliferation and death of human hepatoma cells. Results IL-12 induced autophagy and inhibited cell growth in the hepatoma cells. Silencing Beclin 1 gene enhanced IL-12-mediated growth inhibition and cell death. Furthermore, IL-12 treatment also decreased the expressions of p-AKT, p-mTOR and p-STAT3. The pretreatment of siSTAT3 or STATTIC inhibited STAT3-enhanced IL-12-induced autophagy. Accordingly, activation of AKT with IGF-1 decreased IL-12-induced autophagy. Conclusion IL-12 could induce autophagy through AKT/mTOR/STAT3 signaling pathways and the induction of autophagy attenuates the growth-inhibitory effect of IL-12 on hepatoma cells.

Thyroid hormone receptor inhibits hepatoma cell migration through transcriptional activation of Dickkopf 4

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chi, Hsiang-Cheng; Liao, Chen-Hsin; Huang, Ya-Hui

Highlights: •T{sub 3} affects DKK4 mRNA and protein expression in HepG2-TR cells. •Regulation of DKK4 by T{sub 3} is at transcriptional level. •DKK4 overexpression suppresses hepatoma cell metastasis. -- Abstract: Triiodothyronine (T{sub 3}) is a potent form of thyroid hormone mediates several physiological processes including cellular growth, development, and differentiation via binding to the nuclear thyroid hormone receptor (TR). Recent studies have demonstrated critical roles of T{sub 3}/TR in tumor progression. Moreover, long-term hypothyroidism appears to be associated with the incidence of human hepatocellular carcinoma (HCC), independent of other major HCC risk factors. Dickkopf (DKK) 4, a secreted protein thatmore » antagonizes the canonical Wnt signaling pathway, is induced by T{sub 3} at both mRNA and protein levels in HCC cell lines. However, the mechanism underlying T{sub 3}-mediated regulation of DKK4 remains unknown. In the present study, the 5′ promoter region of DKK4 was serially deleted, and the reporter assay performed to localize the T{sub 3} response element (TRE). Consequently, we identified an atypical direct repeat TRE between nucleotides −1645 and −1629 conferring T{sub 3} responsiveness to the DKK4 gene. This region was further validated using chromatin immunoprecipitation (ChIP) and electrophoretic mobility shift assay (EMSA). Stable DKK4 overexpression in SK-Hep-1 cells suppressed cell invasion and metastatic potential, both in vivo andin vitro, via reduction of matrix metalloproteinase-2 (MMP-2) expression. Our findings collectively suggest that DKK4 upregulated by T{sub 3}/TR antagonizes the Wnt signal pathway to suppress tumor cell progression, thus providing new insights into the molecular mechanism underlying thyroid hormone activity in HCC.« less

DMFC (3,5-dimethyl-7H-furo[3,2-g]chromen-7-one) regulates Bim to trigger Bax and Bak activation to suppress drug-resistant human hepatoma.

PubMed

Xiang, Jun; Wang, Zhe; Liu, Qianqian; Li, Xia; Sun, Jianguo; Fung, Kwok-Pui; Liu, Feiyan

2017-03-01

3,5-Dimethyl- 7 H-furo[3,2-g]chromen-7-one (DMFC) is a coumarin derivative with anti-cancer activity against human hepatoma cells, but the mechanisms underlying DMFC function in cancer suppression is unknown. In this study, we aimed at elucidating the molecular mechanisms underlying DMFC anti-cancer activity and determining whether DMFC is effective in suppression of drug-resistant human hepatocellular carcinoma. We show here that DMFC effectively suppresses both the parent and the multidrug-resistant hepatoma cell growth in vitro and DMFC suppresses hepatoma cell growth at least in part through inducing tumor cell apoptosis. In the molecular level, we observed that DMFC treatment decreases Bcl-2 level by a post-transcriptional mechanism and activates Bim transcription to increase Bim mRNA and protein level in hepatoma cells. Furthermore, co-immunoprecipitation studies revealed that DMFC-induced Bim interrupts interactions between Bcl-2 and Bax and between Mcl-1 and Bak, resulting in dissociation of Bax from Bcl-2 and Bak from Mcl-1 and subsequent activation of both Bax and Bak. Activation of Bax and Bak leads to mitochondrial outer membrane permeabilization and cytochrome c release. Consistent with its potent apoptosis-inducing activity, DMFC exhibited potent activity against the multidrug-resistant hepatoma xenograft growth in vivo. Therefore, we determine that DMFC suppresses hepatoma growth through decreasing Bcl-2 and increasing Bim to induce tumor cell apoptosis and hold great promise for further development as a therapeutic agent to treat chemoresistant hepatoma.

[Effect of tagalsin on p53 and Bcl-2 expression in hepatoma H(22) tumor-bearing mice].

PubMed

Song, Xiu-qi; Guo, Yun-liang; Wang, Bing-gao; Sun, Shao-jie; Yao, Ru-yong

2011-07-01

To explore the effect and mechanism of tagalsin on hepatoma cells. The animal models were established by transplanting H(22) mouse hepatoma cells to mouse liver, and ten days later the mice were randomly divided into five groups: blank group, carmofur positive group and tagalsin groups, including low-dose, middle-dose and high-dose groups. Then medicine or oil was given to the mice by gastric gavage in consecutive 5 days with a 2-days interval as a course of treatment, two courses in all. All mice were killed at 24 hours after medication, and the survival period, ascites conditions, aggressive conditions intra- or extra-liver, weight changes, tumor volume and spleen index of the tumor-bearing mice were observed. Pathological changes of the tumors were examined. Apoptotic factors p53 and Bcl-2 protien and mRNA were detected by immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR). tagalsin inhibited the hepatoma growth effectively without influencing spleen index to some extent. The tumor inhibition rate of tagalsin low, middle and high dose groups were 17.9%, 63.1% and 71.8%, respectively. Immunohistochemical results showed that the p53 and Bcl-2 protein positive cell counts of the positive control and experimental groups were significantly lower than those of the blank group (P < 0.01). RT-PCR results showed that the p53 mRNA expression was significantly enhanced and Bcl-2 mRNA expression was decreased in the positive control groups and tagalsin treatment groups, especially in the high dose group, compared with those of the blank group (P < 0.05). tagalsin can inhibit the growth of mouse hepatoma cells significantly. The mechanism of its anti-tumor effect may work via up-regulating the wild type p53 gene expression and down-regulating Bcl-2 gene expression and thus regulating tumor cell apoptosis.

Downregulation of miR-210 expression inhibits proliferation, induces apoptosis and enhances radiosensitivity in hypoxic human hepatoma cells in vitro

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Wei, E-mail: detachedy@yahoo.com.cn; Sun, Ting; Cao, Jianping

2012-05-01

Hypoxia is a common feature of solid tumors and an important contributor to tumor radioresistance. miR-210 is the most consistently and robustly induced microRNA under hypoxia in different types of tumor cells and normal cells. In the present study, to explore the feasibility of miR-210 as an effective therapeutic target, lentiviral-mediated anti-sense miR-210 gene transfer technique was employed to downregulate miR-210 expression in hypoxic human hepatoma SMMC-7721, HepG2 and HuH7 cells, and phenotypic changes of which were analyzed. Hypoxia led to an increased hypoxia inducible factor-1{alpha} (HIF-1{alpha}) and miR-210 expression and cell arrest in the G{sub 0}/G{sub 1} phase inmore » all cell lines. miR-210 downregulation significantly suppressed cell viability, induced cell arrest in the G{sub 0}/G{sub 1} phase, increased apoptotic rate and enhanced radiosensitivity in hypoxic human hepatoma cells. Moreover, apoptosis-inducing factor, mitochondrion-associated, 3 (AIFM3) was identified as a direct target gene of miR-210. AIFM3 downregulation by siRNA attenuated radiation induced apoptosis in miR-210 downregulated hypoxic human hepatoma cells. Taken together, these data suggest that miR-210 might be a potential therapeutic target and specific inhibition of miR-210 expression in combination with radiotherapy might be expected to exert strong anti-tumor effect on hypoxic human hepatoma cells. -- Highlights: Black-Right-Pointing-Pointer miR-210 downregulation radiosensitized hypoxic hepatoma. Black-Right-Pointing-Pointer AIFM3 was identified as a direct target gene of miR-210. Black-Right-Pointing-Pointer miR-210 might be a therapeutic target to hypoxic hepatoma.« less

Coordinated pH/redox dual-sensitive and hepatoma-targeted multifunctional polymeric micelle system for stimuli-triggered doxorubicin release: Synthesis, characterization and in vitro evaluation.

PubMed

Wang, Lele; Tian, Baocheng; Zhang, Jing; Li, Keke; Liang, Yan; Sun, Yujie; Ding, Yuanyuan; Han, Jingtian

2016-03-30

Multifunctional polymeric micelles self-assembled from a DOX-conjugated methoxypolyethylene glycols-b-poly (6-O-methacryloyl-D-galactopyranose)-disulfide bond-DOX (mPEG-b-PMAGP-SS-DOX) copolymer were prepared as an antitumor carrier for doxorubicin delivery, of which the chemical modification with disulfide bonds and hydrazone bonds allowed micelles to release doxorubicin (DOX) selectively at acidic pH and high redox conditions. The resulting micelles exhibited coordinated pH/redox dual-sensitive and hepatoma-targeted multifunction with sustaining stability in aqueous media. The multifunctional micelles showed spherical shapes with a mean diameter of 93 ± 2.08 nm, a low polydispersity index (PDI) of 0.21, a low CMC value of 0.095 mg/mL, a high drug grafting degree of 56.9% and a drug content of 39.0%. Remarkably, in vitro drug release studies clearly exhibited a pH and redox dual-sensitive drug release profile with significantly accelerated drug release treated with pH 5.0 and 10mM GSH (88.4% in 72 h) without drug burst release. The tumor proliferation assays indicated that DOX-grafted micelles, along with low cytotoxicity and well biocompatibility to normal cells up to a concentration of 10 μg/mL, inhibited the proliferation of HepG2 cells in a formulation-, time- and concentration-dependent manner in comparison with MCF-7 cells which was similar to free DOX. Anticancer activity releaved that the disulfide-modified micelles possessed much higher anti-hepatoma activity with a low IC50 value of 1.1 μg/mL following a 72 h incubation. Furthermore, the intracellular uptake tested by CLSM and FCM demonstrated that multifunctional polymeric micelles could be more efficiently taken up by HepG2 cells compared with MCF-7 cells, agreed well with MTT assays, suggesting these well-defined micelles provide a potential drug delivery system for dual-responsive controlled drug release and enhanced anti-hepatoma therapy. Copyright © 2016 Elsevier B.V. All rights reserved.

Role of hypoxia-inducible factor-{alpha} in hepatitis-B-virus X protein-mediated MDR1 activation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han, Hyo-Kyung; Han, Chang Yeob; Cheon, Eun-Pa

2007-06-01

The transition from chemotherapy-responsive cancer cells to chemotherapy-resistant cancer cells is mainly accompanied by the increased expression of multi-drug resistance 1 (MDR1). We found that hepatitis-B-virus X protein (HBx) increases the transcriptional activity and protein level of MDR1 in a hepatoma cell line, H4IIE. In addition, HBx overexpression made H4IIE cells more resistant to verapamil-uptake. HBx stabilized hypoxia-inducible factor-1{alpha} (HIF-1{alpha}) and induced the nuclear translocation of C/EBP{beta}. Reporter gene analyses showed that HBx increased the reporter activity in the cells transfected with the reporter containing MDR1 gene promoter. Moreover, the luciferase reporter gene activity was significantly inhibited by HIF-1{alpha} siRNAmore » but not by overexpression of C/EBP dominant negative mutant. These results imply that HBx increases the MDR1 transporter activity through the transcriptional activation of the MDR1 gene with HIF-1{alpha} activation, and suggest HIF-1{alpha} for the therapeutic target of HBV-mediated chemoresistance.« less

H32, a non-quinone sulfone analog of vitamin K3, inhibits human hepatoma cell growth by inhibiting Cdc25 and activating ERK.

PubMed

Kar, Siddhartha; Wang, Meifang; Ham, Seung Wook; Carr, Brian I

2006-10-01

We previously synthesized a K-vitamin derivative, Cpd 5, which was a potent growth inhibitor of human tumor cells, including Hep3B hepatoma cells. However, being a quinone compound, Cpd 5 has the potential for generating toxic reactive oxygen species (ROS). We therefore synthesized a nonquinone sulfone derivative, H32, which has a sufone group substituting the quinone. The IC50 of H32 for Hep3B cells was found to be 2.5 microM, which was 2.5 and 3.2 times more potent than Cpd 5 and vitamin K3 respectively. It induced apoptosis in Hep3B cells but did not generate ROS when compared to Cpd 5. Interestingly, under similar culture conditions, normal rat hepatocytes were 14-fold more and 7-fold more resistant to the growth inhibitory effects of H32 than Hep3B and PLC/PRF5 cells respectively. H32 preferentially inhibited the activities of the cell cycle controlling Cdc25A phosphatase likely by binding to its catalytic cysteine. As a consequence, it induced inhibitory tyrosine phosphorylation of the Cdc25 substrate kinases Cdk2 and Cdk4 in Hep3B cells and the cells undergo an arrest in the G1 phase of the cell cycle. H32 also induced persistent phosphorylation of the MAPK protein ERK1/2, but marginal JNK1/2 and p38 phosphorylation. The ERK inhibitor U0126, added at least 30 min prior to H32, antagonized the growth inhibition induced by H32. However, the JNK and p38 inhibitors, JNKI-II and SB203580, were not able to antagonize H32 induced growth inhibition. Thus, H32 differentially inhibited growth of normal and liver tumor cells by preferentially inhibiting the actions of Cdc25 phosphatases and inducing persistent ERK phosphorylation.

Effects of hypoxia-inducible factor-1α silencing on the proliferation of CBRH-7919 hepatoma cells

PubMed Central

Xu, Lin-Feng; Ni, Jia-Yan; Sun, Hong-Liang; Chen, Yao-Ting; Wu, Yu-Dan

2013-01-01

AIM: To study the effects of hypoxia-inducible factor-1α (HIF-1α) silencing on the proliferation of hypoxic CBRH-7919 rat hepatoma cells. METHODS: The CBRH-7919 rat hepatoma cell line was used in this study and the hypoxic model was constructed using CoCl2. The HIF-1α-specific RNAi sequences were designed according to the gene coding sequence of rat HIF-1α obtained from GeneBank. The secondary structure of the HIF-1α gene sequence was analyzed using RNA draw software. The small interfering RNA (siRNA) transfection mixture was produced by mixing the siRNA and Lipofectamine2000TM, and transfected into the hypoxic hepatoma cells. Real time reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting assay were used to detect the expression levels of mRNA and protein. HIF-1α and vascular endothelial growth factor (VEGF) mRNA was determined using real time RT-PCR; the protein expression levels of AKT, p-AKT, p21 and cyclinD1 were determined using Western blotting. The proliferation of hepatoma cells was observed using the methyl thiazolyl tetrazolium (MTT) assay and the bromodeoxyuridine (BrdU) incorporation cell proliferation assay. RESULTS: Under induced hypoxia, the viability of the hepatoma cells reached a minimum at 800 μmol/L CoCl2; the viability of the cells was relatively high at CoCl2 concentrations between 100 μmol/L and 200 μmol/L. Under hypoxia, the mRNA and protein expression levels of HIF-1α and VEGF were significantly higher than that of hepatoma cells that were cultured in normaxia. HIF-1α-specific RNAi sequences were successfully transfected into hepatoma cells. The transfection of specific siRNAs significantly inhibited the mRNA and protein expression levels of HIF-1α and VEGF, along with the protein expression levels of p-AKT and cyclinD1; the protein expression of p21 was significantly increased, and there was no significant difference in the expression of AKT. The MTT assay showed that the amount of hepatoma cells in S

Effects of β-caryophyllene and Murraya paniculata essential oil in the murine hepatoma cells and in the bacteria and fungi 24-h time-kill curve studies.

PubMed

Selestino Neta, Maria Cipriano; Vittorazzi, Catia; Guimarães, Aline Cristina; Martins, João Damasceno Lopes; Fronza, Marcio; Endringer, Denise Coutinho; Scherer, Rodrigo

2017-12-01

Orange Jessamine [Murraya paniculata L. (Rutaceae)] has been used worldwide in folk medicine as an anti-inflammatory, antibiotic and analgesic. The objective of this study is to investigate the in vitro antioxidant, cytotoxic, antibacterial and antifungal activity and the time-kill curve studies of orange jessamine essential oil and β-caryophyllene, as well as the chemical composition of the essential oil. The cytotoxic activity of M. paniculata and β-caryophyllene (7.8-500 μg/mL) was evaluated using the MTT assay on normal fibroblasts and hepatoma cells. The minimal inhibitory concentration and time-kill curves (24 h) were evaluated against those of Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, Enterococcus faecallis, Aspergillus (niger, fumigates and parasiticum) and F. solani by the broth microdilution method. The antioxidant activity was measured by the DPPH and ABTS assays. Chemical composition was evaluated by GC/MS analyses. GC/MS analyses identified 13 compounds, with β-caryophyllene as the major compound. The oil exhibited moderate antibacterial activity (MIC <1.0 mg/mL) and strong antifungal activity. Time-kill curve studies showed that either the essential oil or β-caryophyllene presented rapid bacterial killing (4 h for S. aureus) and fungicidal effect (2-4 h for F. solani); however, both displayed weak free radical scavenger capacity. The cytotoxic activity exhibited a prominent selective effect against hepatoma cancer cells (IC 50 value =63.7 μg/mL) compared with normal fibroblasts (IC 50 value =195.0 μg/mL), whereas the β-caryophyllene showed low cytotoxicity. The experimental data suggest that the activities of M. paniculata essential oil are due to the synergistic action among its components.

Spontaneous apoptosis in a rat hepatoma cell line and its inhibition by dexamethasone.

PubMed

Chaya, D; Fougère-Deschatrette, C; Weiss, M C

1996-01-01

Cultures of dedifferentiated rat hepatoma Rab1-5-1 cells exhibit spontaneously a high level of mortality during the exponential growth phase. We demonstrate that these cells die by apoptosis, showing chromatin condensation and internucleosomal DNA fragmentation. Cells of the original H4II cell line and of its differentiated and dedifferentiated derivatives also die by apoptosis, but only in heavily confluent cultures. We evaluated mortality with time in Rab1-5-1 cultures by establishing growth curves, including quantification of floating cells, and conclude that up to half of the cells in a culture are lost to apoptosis. The production of apoptotic cells is abolished by the presence of 10(-6) M dexamethasone and this inhibition is reversible in 48 hours. Rab1-5-1 cells that spontaneously die by apoptosis with high frequency represent a novel model to investigate factors that regulate the spontaneous frequency of death, and to study the nature and the kinetics of commitment to the apoptotic pathway.

Species-specific differences in peroxisome proliferation, catalase, and SOD2 upregulation as well as toxicity in human, mouse, and rat hepatoma cells induced by the explosive and environmental pollutant 2,4,6-trinitrotoluene.

PubMed

Naumenko, Ekaterina Anatolevna; Ahlemeyer, Barbara; Baumgart-Vogt, Eveline

2017-03-01

2,4,6-Trinitrotoluene (TNT) has been widely used as an explosive substance and its toxicity is still of interest as it persisted in polluted areas. TNT is metabolized in hepatocytes which are prone to its toxicity. Since analysis of the human liver or hepatocytes is restricted due to ethical reasons, we investigated the effects of TNT on cell viability, reactive oxygen species (ROS) production, peroxisome proliferation, and antioxidative enzymes in human (HepG2), mouse (Hepa 1-6), and rat (H4IIEC3) hepatoma cell lines. Under control conditions, hepatoma cells of all three species were highly comparable exhibiting identical proliferation rates and distribution of their cell cycle phases. However, we found strong differences in TNT toxicity with the lowest IC 50 values (highest cell death rate) for rat cells, whereas human and mouse cells were three to sevenfold less sensitive. Moreover, a strong decrease in cellular dehydrogenase activity (MTT assay) and increased ROS levels were noted. TNT caused peroxisome proliferation with rat hepatoma cells being most responsive followed by those from mouse and human. Under control conditions, rat cells contained fivefold higher peroxisomal catalase and mitochondrial SOD2 activities and a twofold higher capacity to reduce MTT than human and mouse cells. TNT treatment caused an increase in catalase and SOD2 mRNA and protein levels in human and mouse, but not in rat cells. Similarly, human and mouse cells upregulated SOD2 activity, whereas rat cells failed therein. We conclude that TNT induced oxidative stress, peroxisome proliferation and mitochondrial damage which are highest in rat cells rendering them most susceptible toward TNT. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 989-1006, 2017. © 2016 Wiley Periodicals, Inc.

The formation of IIE iron meteorites investigated by the chondrule-bearing Mont Dieu meteorite

NASA Astrophysics Data System (ADS)

van Roosbroek, N.; Debaille, V.; Pittarello, L.; Goderis, S.; Humayun, M.; Hecht, L.; Jourdan, F.; Spicuzza, M. J.; Vanhaecke, F.; Claeys, Ph.

2015-07-01

A 435 kg piece of the Mont Dieu iron meteorite (MD) contains cm-sized silicate inclusions. Based on the concentration of Ni, Ga, Ge, and Ir (8.59 ± 0.32 wt%, 25.4 ± 0.9 ppm, 61 ± 2 ppm, 7.1 ± 0.4 ppm, respectively) in the metal host, this piece can be classified as a IIE nonmagmatic iron. The silicate inclusions possess a chondritic mineralogy and relict chondrules occur throughout the inclusions. Major element analysis, oxygen isotopic analysis (Δ17O = 0.71 ± 0.02‰), and mean Fa and Fs molar contents (Fa15.7 ± 0.4 and Fs14.4 ± 0.5) indicate that MD originated as an H chondrite. Because of strong similarities with Netschaëvo IIE, MD can be classified in the most primitive subgroup of the IIE sequence. 40Ar/39Ar ages of 4536 ± 59 Ma and 4494 ± 95 Ma obtained on pyroxene and plagioclase inclusions show that MD belongs to the old (~4.5 Ga) group of IIE iron meteorites and that it has not been perturbed by any subsequent heating event following its formation. The primitive character of MD sheds light on the nature of its formation process, its thermal history, and the evolution of its parent body.

MiR-30e suppresses proliferation of hepatoma cells via targeting prolyl 4-hydroxylase subunit alpha-1 (P4HA1) mRNA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feng, Guoxing; Shi, Hui; Li, Jiong

Aberrant microRNA expression has been shown to be characteristic of many cancers. It has been reported that the expression levels of miR-30e are decreased in liver cancer tissues. However, the role of miR-30e in hepatocellular carcinoma remains poorly understood. In the present study, we investigated the significance of miR-30e in hepatocarcinogenesis. Bioinformatics analysis reveals a putative target site of miR-30e in the 3′-untranslated region (3′UTR) of prolyl 4-hydroxylase subunit alpha-1 (P4HA1) mRNA. Moreover, luciferase reporter gene assays verified that miR-30e directly targeted 3′UTR of P4HA1 mRNA. Then, we demonstrated that miR-30e was able to reduce the expression of P4HA1 atmore » the levels of mRNA and protein using reverse transcription-polymerase chain reaction and Western blot analysis. Enforced expression of miR-30e suppressed proliferation of HepG2 cells by 5-ethynyl-2-deoxyuridine (EdU) assay and reduced colony formation of these cells by colony formation analysis. Conversely, anti-miR-30e enhanced the proliferation of hepatoma cells in vitro. Interestingly, the ectopic expression of P4HA1 could efficiently rescue the inhibition of cell proliferation mediated by miR-30e in HepG2 cells. Meanwhile, silencing of P4HA1 abolished the anti-miR-30e-induced proliferation of cells. Clinically, quantitative real-time PCR showed that miR-30e was down-regulated in liver tumor tissues relative to their peritumor tissues. The expression levels of miR-30e were negatively correlated to those of P4HA1 mRNA in clinical liver tumor tissues. Thus, we conclude that miR-30e suppresses proliferation of hepatoma cells through targeting P4HA1 mRNA. Our finding provides new insights into the mechanism of hepatocarcinogenesis. - Highlights: • P4HA1 is a novel target gene of miR-30e. • P4HA1 is increased in clinical HCC tissues. • MiR-30e is negatively correlated with P4HA1 in clinical HCC tissues. • MiR-30e suppresses the proliferation of HCC cells

Retinoic acid-related orphan receptor alpha reprograms glucose metabolism in glutamine-deficient hepatoma cells.

PubMed

Byun, Jun-Kyu; Choi, Yeon-Kyung; Kang, Yu Na; Jang, Byoung Kuk; Kang, Koo Jeong; Jeon, Yong Hyun; Lee, Ho-Won; Jeon, Jae-Han; Koo, Seung-Hoi; Jeong, Won-Il; Harris, Robert A; Lee, In-Kyu; Park, Keun-Gyu

2015-03-01

The metabolism of glutamine and glucose is recognized as a promising therapeutic target for the treatment of cancer; however, targeted molecules that mediate glutamine and glucose metabolism in cancer cells have not been addressed. Here, we show that restricting the supply of glutamine in hepatoma cells, including HepG2 and Hep3B cells, markedly increased the expression of retinoic acid-related orphan receptor alpha (RORα). Up-regulation of RORα in glutamine-deficient hepatoma cells resulted from an increase in the level of cellular reactive oxygen species and in the nicotinamide adenine dinucleotide phosphate/nicotinamide adenine dinucleotide phosphate reduced (NADP+ /NADPH) ratio, which was consistent with a reduction in the glutathione/glutathione disulfide (GSH/GSSG) ratio. Adenovirus (Ad)-mediated overexpression of RORα (Ad-RORα) or treatment with the RORα activator, SR1078, reduced aerobic glycolysis and down-regulated biosynthetic pathways in hepatoma cells. Ad-RORα and SR1078 reduced the expression of pyruvate dehydrogenase kinase 2 (PDK2) and inhibited the phosphorylation of pyruvate dehydrogenase and subsequently shifted pyruvate to complete oxidation. The RORα-mediated decrease in PDK2 levels was caused by up-regulation of p21, rather than p53. Furthermore, RORα inhibited hepatoma growth both in vitro and in a xenograft model in vivo. We also found that suppression of PDK2 inhibited hepatoma growth in a xenograft model. These findings mimic the altered glucose utilization and hepatoma growth caused by glutamine deprivation. Finally, tumor tissue from 187 hepatocellular carcinoma patients expressed lower levels of RORα than adjacent nontumor tissue, supporting a potential beneficial effect of RORα activation in the treatment of liver cancer. RORα mediates reprogramming of glucose metabolism in hepatoma cells in response to glutamine deficiency. The relationships established here between glutamine metabolism, RORα expression and signaling, and

Metabolism of the tropine indole-3-carboxylate ICS 205-930 by differentiated rat and human hepatoma cells.

PubMed

Fischer, V; Baldeck, J P; Wiebel, F J

The metabolism of the tropine indole-3-carboxylate ICS 205-930 (ICS), a highly potent and selective antagonist of 5-HT3 receptors, was investigated in continuous cell lines derived from rat or human liver and compared to the in vivo metabolism in rat and human. The well-differentiated rat hepatoma line 2sFou extensively metabolized ICS by hydroxylation of the indole moiety and subsequent conjugation to form the corresponding glucuronides and sulfates. The 2sFou cells also oxidized ICS at the tropinyl moiety to form both N-demethyl and N-oxide derivatives. The relative amount of the various metabolites was dependent on the substrate concentration. Pretreatment of the cells with dexamethasone increased the rate of metabolism for all pathways, while benz[a]anthracene caused an increase in hydroxylation at the indole moiety at the expense of N-oxidation. Phenobarbital pretreatment had no effect on ICS metabolism. The pattern of metabolites formed in 2sFou cells was qualitatively similar to that formed in rat urine. The human hepatoma line HepG2 metabolized ICS only to a small extent. The HepG2 cells failed to form detectable amounts of ICS conjugates found in human urine. The N-oxide-ICS was not found in HepG2 cells or in human urine. Virtually no ICS metabolites were found in human lung adenocarcinoma lines NCI-H358 or NCI-H322. The results suggest that continuous cell lines such as the differentiated rat hepatoma cells 2sFou might be used to mimic the metabolism of xenobiotics in rat and to clarify their complex metabolic pathways.

[Transformation of attached cells derived from fetal umbilical cord blood induced by conditional medium of hepatoma cells].

PubMed

Zhang, Xiao-Dong; Cai, Na; Wang, Hong-Hui; Guo, Shi-Yi; Ye, Li-Hong

2006-01-01

Stem cells derived from fetal umbilical cord blood are of undifferentiated at early stage. They are sensitive to stimulations from the environment, and may be transformed under the effects of carcinogenic factors. This study was to explore the sensitivity of stem cells derived from fetal umbilical cord blood to carcinogenic factors. Mononuclear cells were isolated from fetal umbilical cord blood, and the attached cells were cultured in the medium containing 10% conditional medium of HepG2 hepatoma cells. A new cell line was gained, termed H-UCB. The biological features of H-UCB cells were detected by electron microscopy, karyotype analysis, cell cytometry, Western blot, and colony formation assay. H-UCB cells proliferated faster after passage 3. The cells were fibroblast-like and hepatocyte-like, with the ratio of nucleus to cytoplasm increased. Under electron microscope, many microvilli on the surface and numbers of vacuoles in the cytoplasm of the cells were observed, the nuclei were large and irregular, endocytosis phenomena were noticed. Karyotype analysis indicated that the cells were heteroploid, and the number of chromosomes was between 50 and 70. Flow cytometry data indicated that the proliferation period was 22.9 h, and the karyotype was between diploid and tetraploid. Western blot showed that c-Myc protein and proliferating cell nuclear antigen (PCNA) were overexpressed in H-UCB cells. According to flow cytometry, the positive rates of surface markers of H-UCB cells were 79.0% for CD105, 1.2% for CD34, and 12.2% for CD106; those of control HepG2 cells were 15.0% for CO105, 9.8% for CD34, and 1.4% for CD106. The colony formation rate of H-UCB cells in soft agar was (13.2+/-2.6)%. H-UCB cells are derived from endothelial cells, and are transformed as malignant cells with tumor cell characteristics.

Trichloroethylene toxicity in a human hepatoma cell line

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thevenin, E.; McMillian, J.

1994-12-31

The experiments conducted in this study were designed to determine the usefullness of hepatocyte cultures and a human hepatoma cell line as model systems for assessing human susceptibility to hepatocellular carcinoma due to exposure to trichloroethylene. The results from these studies will then be analyzed to determine if human cell lines can be used to conduct future experiments of this nature.

Morphogenic Protein RodZ Interacts with Sporulation Specific SpoIIE in Bacillus subtilis.

PubMed

Muchová, Katarína; Chromiková, Zuzana; Bradshaw, Niels; Wilkinson, Anthony J; Barák, Imrich

2016-01-01

The first landmark in sporulation of Bacillus subtilis is the formation of an asymmetric septum followed by selective activation of the transcription factor σF in the resulting smaller cell. How the morphological transformations that occur during sporulation are coupled to cell-specific activation of transcription is largely unknown. The membrane protein SpoIIE is a constituent of the asymmetric sporulation septum and is a crucial determinant of σF activation. Here we report that the morphogenic protein, RodZ, which is essential for cell shape determination, is additionally required for asymmetric septum formation and sporulation. In cells depleted of RodZ, formation of asymmetric septa is disturbed and σF activation is perturbed. During sporulation, we found that SpoIIE recruits RodZ to the asymmetric septum. Moreover, we detected a direct interaction between SpoIIE and RodZ in vitro and in vivo, indicating that SpoIIE-RodZ may form a complex to coordinate asymmetric septum formation and σF activation. We propose that RodZ could provide a link between the cell shape machinery and the coordinated morphological and developmental transitions required to form a resistant spore.

Synthesis and cytotoxic activity evaluation of some novel 1-(3-(aryl-4,5-dihydroisoxazol-5-yl)methyl)-4-trihalomethyl-1H-pyrimidin-2-ones in human cancer cells.

PubMed

Lobo, Marcio M; Viau, Cassiana M; Dos Santos, Josiane M; Bonacorso, Helio G; Martins, Marcos A P; Amaral, Simone S; Saffi, Jenifer; Zanatta, Nilo

2015-08-28

The synthesis of a series of 14 new 1-(3-(aryl-4,5-dihydroisoxazol-5-yl)methyl)-4-trihalomethyl-1H-pyrimidin-2-ones from the 1,3-dipolar cycloaddition reaction of 1-allyl-4-(trihalomethyl)pyrimidin-2(1H)-ones with aryl nitrile oxides is described. Also, the antiproliferative activity of the title compounds was tested against five human tumoral cell lines: MCF-7 breast cancer cell line, ER+ (estrogen receptor positive); HepG-2 (hepatoma); T-24 (bladder cancer); HCT-116 cell (colorectal carcinoma); and CACO-2. The preliminary results are promising, since three compounds presented IC50 values below 2 μM, as well as moderate to high selectivity. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Cell surface GRP78 facilitates hepatoma cells proliferation and migration by activating IGF-IR.

PubMed

Yin, Yancun; Chen, Chen; Chen, Jinliang; Zhan, Renhui; Zhang, Qiang; Xu, Xiaoyan; Li, Defang; Li, Minjing

2017-07-01

The 78kDa glucose regulated protein (GRP78) is a multifunctional chaperone that is involved in a variety of cellular processes. Insulin like growth factor I receptor (IGF-IR) often aberrant expresses in many types of tumor cells. The IGF-IR signaling plays key roles in carcinogenesis and maintenance of the malignant phenotype. The crosstalk between GRP78 and IGF-IR molecules has not well been illuminated. Here, we demonstrated a reciprocal regulation of GRP78 expression and IGF-IR pathway activation. IGF-I induced GRP78 expression in hepatoma cells. IGF-IR knockdown or IGF-IR inhibitor repressed GRP78 expression. Both phosphatidylinositol 3-kianase (PI3K) and mitogen-activated protein kinase (MAPK) pathways involved in IGF-I induction of GRP78 expression. Interestingly, treatment of hepatoma cells with IGF-I re-distributes GRP78 from endoplasmic reticulum (ER) to cell surface and promotes its physical interaction with IGF-IR. Also, GRP78 promotes IGF-IR phosphorylation and activation. Blocked of GRP78 by small interfering RNA or inhibition of GRP78 function by (-)-epigallocatechin gallate (EGCG) blocks IGF-I induced IGF-IR phosphorylation and its downstream signaling. Further, blocked cell surface GRP78 with antibody inhibits IGF-I stimulated cellular proliferation and migration. These data reveal an essential role for the molecular chaperone GRP78 in IGF-IR signaling and implicate the use of GRP78 inhibitors in blocking IGF-IR signaling in hepatoma cells. Copyright © 2017 Elsevier Inc. All rights reserved.

Molecular switch of Cre/loxP for radiation modulated gene therapy on hepatoma

NASA Astrophysics Data System (ADS)

Hsieh, Ya-Ju; Chen, Fu-Du; Wang, Fu Hui; Ke, Chien Chih; Wang, Hsin-Ell; Liu, Ren-Shyan

2007-02-01

For the purpose of enhancement of AFP promoter for the use of radiation modulated gene therapy for hepatocellular carcinoma (HCC), we combined hepatitis B virus (HBV) enhancer II with AFP promoter which shows the selectivity to the target cells to control the Cre/loxP system. Different gene constructs, pE4luc, pE4Tk, EIIAPA-Cre, E4CMV-STOP-Tk and chimeric promoters combined with HBV enhancer were constructed and transfected into HepG2, HeLa and NIH-3T3 cell lines. Cell experiments revealed that E4 enhancer responses to radiation best after 60 h irradiation at a dose range of 5-7 Gy in HepG2 stable clone. The EIIAPA promoter provided high specificity to hepatoma and activated the Cre downstream and removed the stop cassette only in hepatoma cells. After removal of the stop cassette, the E4 response to radiation could encode more Tk protein and kill more tumor cells. In summary, the chimeric EIIAPA promoter can stringently control the expression of Cre recombinase only in HCC. The radiation effect of the EIIAPA-Cre and E4CMV-STOP-Tk system shows promising results in terms of cell survival of HCC.

Cytochrome P4501A induction, benzo[a]pyrene metabolism, and nucleotide adduct formation in fish hepatoma cells: Effect of preexposure to 3,3',4,4',5-pentachlorobiphenyl

USGS Publications Warehouse

Smeets, J.M.W.; Voormolen, A.; Tillitt, D.E.; Everaarts, J.M.; Seinen, W.; Vanden Berg, M.D.

1999-01-01

In PLHC-1 hepatoma cells, benzo[a]pyrene (B[a]P) caused a maximum induction of cytochrome P4501A (CYP1A) activity, measured as ethoxyresorufin O-deethylation (EROD), after 4 to 8 h of exposure, depending on the B[a]P concentration. The decline of EROD activity at longer exposure times was probably caused by the rapid metabolism of B[a]P in this system (57% metabolism within 4 h incubation). In subsequent experiments, PLHC-1 cells were preinduced with PCB 126 for 24 h and then received a dose of 10, 100, or 1,000 nM 3H-B[a]P. A 1-nM concentration of PCB 126 caused an 80-fold induction of CYP1A activity, resulting in an increase in B[a]P metabolism of less than 10%, except at the highest concentration of B[a]P (1,000 nM), where a 50% increase was observed. In another experiment, an 80-fold induction of CYP1A activity caused a 20% increase in the metabolism of B[a]P (100 nM), and RNA adduct formation was increased approximately twofold. These results indicate that, at exposure concentrations up to 100 nM B[a]P, CYP1A activity is not rate limiting for B[a]P metabolism. Furthermore, CYP1A seems to also he specifically involved in B[a]P activation in PLHC-1 cells. However, CYP1A induction causes only a relatively small increase in activation, probably because of the action of other enzymes involved in B[a]P activation and deactivation.

Enhanced proliferation of human hepatoma cells by PAR-2 agonists via the ERK/AP-1 pathway.

PubMed

Xie, Liqun; Zheng, Yanmin; Li, Xuan; Zhao, Junyan; Chen, Xiaoyi; Chen, Li; Zhou, Jing; Hai, Ou; Li, Fei

2012-11-01

To investigate the expression and role of PAR-2 in the proliferation of the human hepatoma cell line HepG2, PAR-2 protein and mRNA expression were evaluated by immuno-histochemistry, immunofluorescence and RT-PCR analysis. The signaling pathways downstream of PAR-2 activation that lead to hepatoma cell proliferation were analyzed. The results showed that PAR-2 is expressed in human hepatoma cells and PAR-2 mRNA expression was found to be upregulated in cells treated with trypsin or SLIGKV-NH2 (P<0.001). The proliferation rate of HepG2 cells treated with trypsin or SLIGKV-NH2 was significantly increased (P<0.001). The percentage of S phase, G2/M phase and the proliferation index (PI) of HepG2 cells treated with trypsin or SLIGKV-NH2 were significantly elevated (P<0.001). The proliferative responses of HepG2 to trypsin and SLIGKV-NH2 were associated with the upregulation of c-fos and PCNA, which were significantly blocked by PD98059 pretreatment. In conclusion, our results indicate that PAR-2 enhances proliferation of human hepatoma cells possibly via the ERK/AP-1 pathway.

Mitochondrial aquaporin-8 knockdown in human hepatoma HepG2 cells causes ROS-induced mitochondrial depolarization and loss of viability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marchissio, Maria Julia; Francés, Daniel Eleazar Antonio; Carnovale, Cristina Ester

Human aquaporin-8 (AQP8) channels facilitate the diffusional transport of H{sub 2}O{sub 2} across membranes. Since AQP8 is expressed in hepatic inner mitochondrial membranes, we studied whether mitochondrial AQP8 (mtAQP8) knockdown in human hepatoma HepG2 cells impairs mitochondrial H{sub 2}O{sub 2} release, which may lead to organelle dysfunction and cell death. We confirmed AQP8 expression in HepG2 inner mitochondrial membranes and found that 72 h after cell transfection with siRNAs targeting two different regions of the human AQP8 molecule, mtAQP8 protein specifically decreased by around 60% (p < 0.05). Studies in isolated mtAQP8-knockdown mitochondria showed that H{sub 2}O{sub 2} release, assessedmore » by Amplex Red, was reduced by about 45% (p < 0.05), an effect not observed in digitonin-permeabilized mitochondria. mtAQP8-knockdown cells showed an increase in mitochondrial ROS, assessed by dichlorodihydrofluorescein diacetate (+ 120%, p < 0.05) and loss of mitochondrial membrane potential (− 80%, p < 0.05), assessed by tetramethylrhodamine-coupled quantitative fluorescence microscopy. The mitochondria-targeted antioxidant MitoTempol prevented ROS accumulation and dissipation of mitochondrial membrane potential. Cyclosporin A, a mitochondrial permeability transition pore blocker, also abolished the mtAQP8 knockdown-induced mitochondrial depolarization. Besides, the loss of viability in mtAQP8 knockdown cells verified by MTT assay, LDH leakage, and trypan blue exclusion test could be prevented by cyclosporin A. Our data on human hepatoma HepG2 cells suggest that mtAQP8 facilitates mitochondrial H{sub 2}O{sub 2} release and that its defective expression causes ROS-induced mitochondrial depolarization via the mitochondrial permeability transition mechanism, and cell death. -- Highlights: ► Aquaporin-8 is expressed in mitochondria of human hepatoma HepG2 cells. ► Aquaporin-8 knockdown impairs mitochondrial H{sub 2}O{sub 2} release and increases ROS. �

Esculetin-induced protection of human hepatoma HepG2 cells against hydrogen peroxide is associated with the Nrf2-dependent induction of the NAD(P)H: Quinone oxidoreductase 1 gene

DOE Office of Scientific and Technical Information (OSTI.GOV)

Subramaniam, Sudhakar R.; Ellis, Elizabeth M., E-mail: elizabeth.ellis@strath.ac.uk

Esculetin (6,7-dihydroxy coumarin), is a potent antioxidant that is present in several plant species. The aim of this study was to investigate the mechanism of protection of esculetin in human hepatoma HepG2 cells against reactive oxygen species (ROS) induced by hydrogen peroxide. Cell viability, cell integrity, intracellular glutathione levels, generation of reactive oxygen species and expression of antioxidant enzymes were used as markers to measure cellular oxidative stress and response to ROS. The protective effect of esculetin was compared to a well-characterized chemoprotective compound quercetin. Pre-treatment of HepG2 cells with sub-lethal (10-25 {mu}M) esculetin for 8 h prevented cell deathmore » and maintained cell integrity following exposure to 0.9 mM hydrogen peroxide. An increase in the generation of ROS following hydrogen peroxide treatment was significantly attenuated by 8 h pre-treatment with esculetin. In addition, esculetin ameliorated the decrease in intracellular glutathione caused by hydrogen peroxide exposure. Moreover, treatment with 25 {mu}M esculetin for 8 h increased the expression of NAD(P)H: quinone oxidoreductase (NQO1) at both protein and mRNA levels significantly, by 12-fold and 15-fold, respectively. Esculetin treatment also increased nuclear accumulation of Nrf2 by 8-fold indicating that increased NQO1 expression is Nrf2-mediated. These results indicate that esculetin protects human hepatoma HepG2 cells from hydrogen peroxide induced oxidative injury and that this protection is provided through the induction of protective enzymes as part of an adaptive response mediated by Nrf2 nuclear accumulation.« less

NDRG2 overexpression suppresses hepatoma cells survival during metabolic stress through disturbing the activation of fatty acid oxidation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pan, Tao; Xi'an Medical University, Xi'an, Shaanxi Province; Zhang, Mei

Because of the high nutrient consumption and inadequate vascularization, solid tumor constantly undergoes metabolic stress during tumor development. Oncogenes and tumor suppressor genes participated in cancer cells' metabolic reprogramming. N-Myc downstream regulated gene 2 (NDRG2) is a recently identified tumor suppressor gene, but its function in cancer metabolism, particularly during metabolic stress, remains unclear. In this study, we found that NDRG2 overexpression significantly reduced hepatoma cell proliferation and enhanced cell apoptosis under glucose limitation. Moreover, NDRG2 overexpression aggravated energy imbalance and oxidative stress by decreasing the intracellular ATP and NADPH generation and increasing ROS levels. Strikingly, NDRG2 inhibited the activationmore » of fatty acid oxidation (FAO), which preserves ATP and NADPH purveyance in the absence of glucose. Finally, mechanistic investigation showed that NDRG2 overexpression suppressed the glucose-deprivation induced AMPK/ACC pathway activation in hepatoma cells, whereas the expression of a constitutively active form of AMPK abrogated glucose-deprivation induced AMPK activation and cell apoptosis. Thus, as a negative regulator of AMPK, NDRG2 disturbs the induction of FAO genes by glucose limitation, leading to dysregulation of ATP and NADPH, and thus reduces the tolerance of hepatoma cells to glucose limitation. - Highlights: • NDRG2 overexpression reduces the tolerance of hepatoma cells to glucose limitation. • NDRG2 overexpression aggravates energy imbalance and oxidative stress under glucose deprivation. • NDRG2 overexpression disturbs the activation of FAO in hepatoma cells under glucose limitation. • NDRG2 overexpression inhibits the activation of AMPK/ACC pathway in hepatoma cells during glucose starvation.« less

[Effect of polychromatic visible light combined with infrared radiation on tumorigenicity of murine hepatoma cells and their sensitivity to lytic activity of natural killers].

PubMed

Filatova, N A; Kniazev, N A; Kosheverova, V V; Shatrova, A N; Samoĭlova, K A

2013-01-01

Tumorigenicity of murine hepatoma cells (MH22a) and their sensitivity to lysis by natural killers (NKs) have been studied after exposure to polychromatic visible and infrared light (VIS-IR, 480-3400 nm, 40 mW/cm2), similar to the terrestrial solar spectrum without its minor UV component, in order to elucidate the involvement of this important environmental and physiotherapeutic factor in regulation of the anti-tumor defense system. The MH22 cells were in vitro exposed to VIS-IR light and their sensitivity to lytic activity of NKs was evaluated. We found that sensitivity of MH22a cells to lysis by NKs after exposure to VIS-IR light at a dose of 4.8 J/cm2 increased 1.5-2 times, while it did not change after exposure to a dose of 9.6 J/cm2 at all ratios (1 : 5-1 : 50) of the number of NKs (effectors) to that of hepatoma cells (targets). The increase in the sensitivity of hepatoma cells to NKs was accompanied by structural changes of cell surface: the capability of supramembraneous glycoproteins (glycocalix) to sorb the vital dye alcian blue (AB) was significantly lower as compared with the unexposed cells of control group. However, no changes in AB sorption was revealed in hepatoma cells exposed to the light at a dose 9.6 J/cm2. Tumorigenicity of photo-irradiated MH22a cells has been studied in the in vivo experiments. Light-exposed (4.8 and 9.6 J/cm2) and intact hepatoma cells were transplanted into syngenic mice C3HA. Tumor volumes 25 days after transplantation proved to be smaller after exposure to the light at both doses than in the control group (4-4.5 times and 2.5-4 times, respectively), which correlated with the increase in the sensitivity to lisys by NKs and decrease in the AB sorption only after light exposure at dose 4.8 J/cm2. Using the flow cytometry method we could show that VIS-IR light at the applied doses did not interfere with the distribution of hepatoma cells over the cycle phases and thus deceleration of the tumor growth was not associated with

Characterization of genetically engineered mouse hepatoma cells with inducible liver functions by overexpression of liver-enriched transcription factors.

PubMed

Yamamoto, Hideaki; Tonello, Jane Marie; Sambuichi, Takanori; Kawabe, Yoshinori; Ito, Akira; Kamihira, Masamichi

2018-01-01

New cell sources for the research and therapy of organ failure could significantly alleviate the shortage of donor livers that are available to patients who suffer from liver disease. Liver carcinoma derived cells, or hepatoma cells, are the ideal cells for developing bioartificial liver systems. Such cancerous liver cells are easy to prepare in large quantities and can be maintained over long periods under standard culture conditions, unlike primary hepatocytes. However, hepatoma cells possess only a fraction of the functions of primary hepatocytes. In a previous study, by transducing cells with liver-enriched transcription factors that could be inducibly overexpressed-hepatocyte nuclear factor (HNF)1α, HNF1β, HNF3β [FOXA2], HNF4α, HNF6, CCAAT/enhancer binding protein (C/EBP)α, C/EBPβ and C/EBPγ-we created mouse hepatoma cells with high liver-specific gene expression called the Hepa/8F5 cell line. In the present study, we performed functional and genetic analyses to characterize the Hepa/8F5 cell line. Further, in three-dimensional cultures, the function of these cells improved significantly compared to parental cells. Ultimately, these cells might become a new resource that can be used in basic and applied hepatic research. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Suppressive effects of caraway (Carum carvi) extracts on 2, 3, 7, 8-tetrachloro-dibenzo-p-dioxin-dependent gene expression of cytochrome P450 1A1 in the rat H4IIE cells.

PubMed

Naderi-Kalali, B; Allameh, A; Rasaee, M J; Bach, H-J; Behechti, A; Doods, K; Kettrup, A; Schramm, K-W

2005-04-01

Cytochrome P450 1A1 (CYP1A1) is among the cytochrome P450 classes known to convert xenobiotics and endogenous compounds to toxic and/or carcinogenic metabolites. Suppression of CYP1A1 over expression by certain compounds is implicated in prevention of cancer caused by chemical carcinogens. Chemopreventive agents containing high levels of flavonoids and steroids-like compounds are known to suppress CYP1A1. This study was carried out for assessment of the genomic and proteomic effects of caraway (Carum carvi) extracts containing high levels of both flavonoids and steroid-like substances on ethoxy resorufin dealkylation (EROD) activity and CYP1A1 at mRNA levels. Rat hepatoma cells co-treated with a CYP1A1 inducer i.e. TCDD (2, 3, 7, 8-tetrachlorodibenzo-p-dioxin) and different preparations of caraway extracts at concentrations of 0, 0.13, 1.3, and 13 microM in culture medium. After incubation (37 degrees C and 7% CO2 for 20 h), changes in EROD specific activity recorded and compared in cells under different treatments. The results show that caraway seed extract prepared in three different organic solvents suppressed the enzyme activity in hepatoma cells in a dose-dependent manner. The extracts added above 0.13 microM could significantly inhibit EROD activity and higher levels of each extract (1.3 and 13 microM) caused approximately 10-fold suppression in the enzyme activity. Accordingly, data obtained from the RT-PCR (TaqMan) clearly showed the suppressive effects of plant extract on CYP1A1-related mRNA expression. These data clearly show that substances in caraway seeds extractable in organic solvents can potentially reverse the TCDD-dependent induction in cytochrome P450 1A1.

Bioactive chemical constituents of Curcuma longa L. rhizomes extract inhibit the growth of human hepatoma cell line (HepG2).

PubMed

Abdel-Lateef, Ezzat; Mahmoud, Faten; Hammam, Olfat; El-Ahwany, Eman; El-Wakil, Eman; Kandil, Sherihan; Abu Taleb, Hoda; El-Sayed, Mortada; Hassenein, Hanaa

2016-09-01

The present study was designed to identify the chemical constituents of the methanolic extract of Curcuma longa L. rhizomes and their inhibitory effect on a hepatoma cell line. The methanolic extract was subjected to GC-MS analysis to identify the volatile constituents and the other part of the same extract was subjected to liquid column chromatographic separation to isolate curcumin. The inhibition of cell growth in the hepatoma cell line and the cytopathological changes were studied. GC-MS analysis showed the presence of fifty compounds in the methanolic extract of C. longa. The major compounds were ar-turmerone (20.50 %), β-sesquiphellandrene (5.20 %) and curcumenol (5.11 %). Curcumin was identified using IR, 1H and 13C NMR. The inhibition of cell growth by curcumin (IC50 = 41.69 ± 2.87 μg mL-1) was much more effective than that of methanolic extract (IC50 = 196.12 ± 5.25 μg mL-1). Degenerative and apoptotic changes were more evident in curcumin- treated hepatoma cells than in those treated with the methanol extract. Antitumor potential of the methanolic extract may be attributed to the presence of sesquiterpenes and phenolic constituents including curcumin (0.051 %, 511.39 μg g-1 dried methanol extract) in C. longa rhizomes.

Hot water-extracted Lycium barbarum and Rehmannia glutinosa inhibit proliferation and induce apoptosis of hepatocellular carcinoma cells

PubMed Central

Chao, Jane C-J; Chiang, Shih-Wen; Wang, Ching-Chiung; Tsai, Ya-Hui; Wu, Ming-Shun

2006-01-01

AIM: To investigate the effect of hot water-extracted Lycium barbarum (LBE) and Rehmannia glutinosa (RGE) on cell proliferation and apoptosis in rat and/or human hepatocellular carcinoma (HCC) cells. METHODS: Rat (H-4-II-E) and human HCC (HA22T/VGH) cell lines were incubated with various concentrations (0-10 g/L) of hot water-extracted LBE and RGE. After 6-24 h incubation, cell proliferation (n = 6) was measured by a colorimetric method. The apoptotic cells (n = 6) were detected by flow cytometry. The expression of p53 protein (n = 3) was determined by SDS-PAGE and Western blotting. RESULTS: Crude LBE (2-5 g/L) and RGE (2-10 g/L) dose-dependently inhibited proliferation of H-4-II-E cells by 11% (P < 0.05) to 85% (P < 0.01) after 6-24 h treatment. Crude LBE at a dose of 5 g/L suppressed cell proliferation of H-4-II-E cells more effectively than crude RGE after 6-24 h incubation (P < 0.01). Crude LBE (2-10 g/L) and RGE (2-5 g/L) also dose-dependently inhibited proliferation of HA22T/VGH cells by 14%-43% (P < 0.01) after 24 h. Crude LBE at a dose of 10 g/L inhibited the proliferation of HA22T/VGH cells more effectively than crude RGE (56.8% ± 1.6% vs 70.3% ± 3.1% of control, P = 0.0003 < 0.01). The apoptotic cells significantly increased in H-4-II-E cells after 24 h treatment with higher doses of crude LBE (2-5 g/L) and RGE (5-10 g/L) (P < 0.01). The expression of p53 protein in H-4-II-E cells was 119% and 143% of the control group compared with the LBE-treated (2, 5 g/L) groups, and 110% and 132% of the control group compared with the RGE -treated (5, 10 g/L) groups after 24 h. CONCLUSION: Hot water-extracted crude LBE (2-5 g/L) and RGE (5-10 g/L) inhibit proliferation and stimulate p53-mediated apoptosis in HCC cells. PMID:16874858

Human serum activates CIDEB-mediated lipid droplet enlargement in hepatoma cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singaravelu, Ragunath; National Research Council of Canada, Ottawa, Ontario K1A 0R6; Lyn, Rodney K.

Highlights: •Human serum induced differentiation of hepatoma cells increases cellular lipid droplet (LD) size. •The observed increase in LD size correlates with increased PGC-1α and CIDEB expression. •Induction of CIDEB expression correlates with rescue of VLDL secretion and loss of ADRP. •siRNA knockdown of CIDEB impairs the human serum mediated increase in LD size. •This system represents a cost-efficient model to study CIDEB’s role in lipid biology. -- Abstract: Human hepatocytes constitutively express the lipid droplet (LD) associated protein cell death-inducing DFFA-like effector B (CIDEB). CIDEB mediates LD fusion, as well as very-low-density lipoprotein (VLDL) maturation. However, there are limitedmore » cell culture models readily available to study CIDEB’s role in these biological processes, as hepatoma cell lines express negligible levels of CIDEB. Recent work has highlighted the ability of human serum to differentiate hepatoma cells. Herein, we demonstrate that culturing Huh7.5 cells in media supplemented with human serum activates CIDEB expression. This activation occurs through the induced expression of PGC-1α, a positive transcriptional regulator of CIDEB. Coherent anti-Stokes Raman scattering (CARS) microscopy revealed a correlation between CIDEB levels and LD size in human serum treated Huh7.5 cells. Human serum treatment also resulted in a rapid decrease in the levels of adipose differentiation-related protein (ADRP). Furthermore, individual overexpression of CIDEB was sufficient to down-regulate ADRP protein levels. siRNA knockdown of CIDEB revealed that the human serum mediated increase in LD size was CIDEB-dependent. Overall, our work highlights CIDEB’s role in LD fusion, and presents a new model system to study the PGC-1α/CIDEB pathway’s role in LD dynamics and the VLDL pathway.« less

Thyroid hormone enhanced human hepatoma cell motility involves brain-specific serine protease 4 activation via ERK signaling

PubMed Central

2014-01-01

Background The thyroid hormone, 3, 3′, 5-triiodo-L-thyronine (T3), has been shown to modulate cellular processes via interactions with thyroid hormone receptors (TRs), but the secretory proteins that are regulated to exert these effects remain to be characterized. Brain-specific serine protease 4 (BSSP4), a member of the human serine protease family, participates in extracellular matrix remodeling. However, the physiological role and underlying mechanism of T3-mediated regulation of BSSP4 in hepatocellular carcinogenesis are yet to be established. Methods The thyroid hormone response element was identified by reporter and chromatin immunoprecipitation assays. The cell motility was analyzed via transwell and SCID mice. The BSSP4 expression in clinical specimens was examined by Western blot and quantitative reverse transcription polymerase chain reaction. Results Upregulation of BSSP4 at mRNA and protein levels after T3 stimulation is a time- and dose-dependent manner in hepatoma cell lines. Additionally, the regulatory region of the BSSP4 promoter stimulated by T3 was identified at positions -609/-594. BSSP4 overexpression enhanced tumor cell migration and invasion, both in vitro and in vivo. Subsequently, BSSP4-induced migration occurs through the ERK 1/2-C/EBPβ-VEGF cascade, similar to that observed in HepG2-TRα1 and J7-TRα1 cells. BSSP4 was overexpressed in clinical hepatocellular carcinoma (HCC) patients, compared with normal subjects, and positively associated with TRα1 and VEGF to a significant extent. Importantly, a mild association between BSSP4 expression and distant metastasis was observed. Conclusions Our findings collectively support a potential role of T3 in cancer cell progression through regulation of the BSSP4 protease via the ERK 1/2-C/EBPβ-VEGF cascade. BSSP4 may thus be effectively utilized as a novel marker and anti-cancer therapeutic target in HCC. PMID:24980078

Thyroid hormone enhanced human hepatoma cell motility involves brain-specific serine protease 4 activation via ERK signaling.

PubMed

Chen, Cheng-Yi; Chung, I-Hsiao; Tsai, Ming-Ming; Tseng, Yi-Hsin; Chi, Hsiang-Cheng; Tsai, Chung-Ying; Lin, Yang-Hsiang; Wang, You-Ching; Chen, Chie-Pein; Wu, Tzu-I; Yeh, Chau-Ting; Tai, Dar-In; Lin, Kwang-Huei

2014-07-01

The thyroid hormone, 3, 3', 5-triiodo-L-thyronine (T3), has been shown to modulate cellular processes via interactions with thyroid hormone receptors (TRs), but the secretory proteins that are regulated to exert these effects remain to be characterized. Brain-specific serine protease 4 (BSSP4), a member of the human serine protease family, participates in extracellular matrix remodeling. However, the physiological role and underlying mechanism of T3-mediated regulation of BSSP4 in hepatocellular carcinogenesis are yet to be established. The thyroid hormone response element was identified by reporter and chromatin immunoprecipitation assays. The cell motility was analyzed via transwell and SCID mice. The BSSP4 expression in clinical specimens was examined by Western blot and quantitative reverse transcription polymerase chain reaction. Upregulation of BSSP4 at mRNA and protein levels after T3 stimulation is a time- and dose-dependent manner in hepatoma cell lines. Additionally, the regulatory region of the BSSP4 promoter stimulated by T3 was identified at positions -609/-594. BSSP4 overexpression enhanced tumor cell migration and invasion, both in vitro and in vivo. Subsequently, BSSP4-induced migration occurs through the ERK 1/2-C/EBPβ-VEGF cascade, similar to that observed in HepG2-TRα1 and J7-TRα1 cells. BSSP4 was overexpressed in clinical hepatocellular carcinoma (HCC) patients, compared with normal subjects, and positively associated with TRα1 and VEGF to a significant extent. Importantly, a mild association between BSSP4 expression and distant metastasis was observed. Our findings collectively support a potential role of T3 in cancer cell progression through regulation of the BSSP4 protease via the ERK 1/2-C/EBPβ-VEGF cascade. BSSP4 may thus be effectively utilized as a novel marker and anti-cancer therapeutic target in HCC.

[Ursodeoxycholic acid induced apoptosis of human hepatoma cells HepG2 and SMMC-7721 bymitochondrial-mediated pathway].

PubMed

Wu, Duan; Zhou, Jianyin; Yin, Zhenyu; Liu, Pingguo; Zhao, Yilin; Liu, Jianming; Wang, Xiaomin

2014-12-02

To explore the effects and underlying mechanisms of ursodeoxycholic acid on human hepatoma cells. HepG2 and SMMC-7721 HCC cell lines were respectively treated with ursodeoxycholic acid. And cell proliferation, apoptosis and the expression of Bax/Bcl-2 gene were detected by methyl thiazolyl tetrazolium (MTT), inverted microscopy, fluorescent microscopy, flow cytometry and Western blot. Ursodeoxycholic acid significantly inhibited the proliferation of human hepatoma cells in a concentration- and time-dependent manner. The half maximal inhibitory concentrations (IC50) of HepG2 and SMMC-7721 were 397.3 and 387.7 µg/ml respectively after a 48-hour treatment of 400 µg /ml ursodeoxycholic acid. And it also induced the apoptosis of HepG2 and SMMC-7721 cells, up-regulated Bax gene and down-regulated Bcl-2 gene. Ursodeoxycholic acid inhibits the proliferation of hepatoma cells and induce apoptosis by mitochondrial-mediated pathway.

Galactose-functionalized multi-responsive nanogels for hepatoma-targeted drug delivery

NASA Astrophysics Data System (ADS)

Lou, Shaofeng; Gao, Shan; Wang, Weiwei; Zhang, Mingming; Zhang, Ju; Wang, Chun; Li, Chen; Kong, Deling; Zhao, Qiang

2015-02-01

a combination of enzymatic transesterification and emulsion copolymerization for intracellular drug delivery. The nanogel exhibited redox, pH and temperature-responsive properties, which can be adjusted by varying the monomer feeding ratio. Furthermore, the volume phase transition temperature (VPTT) of the nanogels was close to body temperature and can result in rapid thermal gelation at 37 °C. Scanning electron microscopy also revealed that the P(ODGal-VCL-MAA) nanogel showed uniform spherical monodispersion. With pyrene as a probe, the fluorescence excitation spectra demonstrated nanogel degradation in response to glutathione (GSH). X-ray diffraction (XRD) showed an amorphous property of DOX within the nanogel, which was used in this study as a model anti-cancer drug. Drug-releasing characteristics of the nanogel were examined in vitro. The results showed multi-responsiveness of DOX release by the variation of environmental pH values, temperature or the availability of GSH, a biological reductase. An in vitro cytotoxicity assay showed a higher anti-tumor activity of the galactose-functionalized DOX-loaded nanogels against human hepatoma HepG2 cells, which was, at least in part, due to specific binding between the galactose segments and the asialoglycoprotein receptors (ASGP-Rs) in hepatic cells. Confocal laser scanning microscopy (CLSM) and flow cytometric profiles further confirmed elevated cellular uptake of DOX by the galactose-functionalised nanogels. Thus, we report here a multi-responsive P(ODGal-VCL-MAA) nanogel with a hepatoma-specific targeting ability for anti-cancer drug delivery. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr06714b

Effects of JS-K, a novel anti-cancer nitric oxide prodrug, on gene expression in human hepatoma Hep3B cells.

PubMed

Dong, Ray; Wang, Xueqian; Wang, Huan; Liu, Zhengyun; Liu, Jie; Saavedra, Joseph E

2017-04-01

JS-K is a novel anticancer nitric oxide (NO) prodrug effective against a variety of cancer cells, including the inhibition of AM-1 hepatoma cell growth in rats. To further evaluate anticancer effects of JS-K, human hepatoma Hep3B cells were treated with JS-K and the compound control JS-43-126 at various concentrations (0-100μM) for 24h, and cytotoxicity was determined by the MTS assay. The compound control JS-43-126 was not cytotoxic to Hep3B cells at concentrations up to 100μM, while the LC 50 for JS-K was about 10μM. To examine the molecular mechanisms of antitumor effects of JS-K, Hep3B cells were treated with 1-10μM of JS-K for 24h, and then subjected to gene expression analysis via real time RT-PCR and protein immunostain via confocal images. JS-K is a GST-α targeting NO prodrug, and decreased immunostaining for GST-α was associated with JS-K treatment. JS-K activated apoptosis pathways in Hep3B cells, including induction of caspase-3, caspase-9, Bax, TNF-α, and IL-1β, and immunostaining for caspase-3 was intensified. The expressions of thrombospondin-1 (TSP-1) and the tissue inhibitors of metalloproteinase-1 (TIMP-1) were increased by JS-K at both transcript and protein levels. JS-K treatment also increased the expression of differentiation-related genes CD14 and CD11b, and depressed the expression of c-myc in Hep3B cells. Thus, multiple molecular events appear to be associated with anticancer effects of JS-K in human hepatoma Hep3B cells, including activation of genes related to apoptosis and induction of genes involved in antiangiogenesis and tumor cell migration. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Chronology and Petrology of Silicates From IIE Iron Meteorites: Evidence of a Complex Parent Body Evolution

NASA Technical Reports Server (NTRS)

Bogard, Donald D.; Garrison, Daniel H.; McCoy, Timothy J.

1999-01-01

IIE iron meteorites contain silicate inclusions whose characteristics suggest a parent body similar to that of H-chondrites. However, these silicates show a wide range of alteration, ranging from Netschadvo and Techado, whose inclusions are little altered. to highly differentiated silicates like-those in Kodaikanal, Weekeroo Station and Colomera, which have lost metal and sulfur and are enriched in feldspar. We find these inclusions to show varying degrees of shock alteration. Because only a limited amount of data on - isotopic ages of HE silicates were available, we made Ar-39 - Ar-40 age determinations of Watson, Techado, miles Colomera, and Sombrerete. Watson has an Ar-Ar age of 3.653 +/- 0.012 Gyr, similar to previously reported ages for Kodaikanal and Netschadvo. We suggest that the various determined radiometric ages of these three meteorites were probably reset by a common impact event. The space exposure ages for these three meteorites are also similar to each other and are considerably younger than exposure ages of other IIEs. Ar-39 - Ar-40 ages inferred for the other four meteorites analyzed are considerably older than Watson and are: Techado =4.49 +/- 0.01 Gyr, Miles =4.412 +/- 0.016 Gyr, Colomera =4.469 +/- 0.012 Gyr, and Sombrerete =4.535 +/- 0.005 Gyr. These ages are in fair agreement with previously reported Rb-Sr isochron ages for Colomera and Weekeroo Station. Although several mechanisms to form HE meteorites previously were suggested, it is not obvious that a single mechanism could produce a suite of meteorites with very different degrees of silicate differentiation and with isotopic ages that differ by >0.8 Gyr. We suggest that those IIEs with older isotopic ages are a product of partial melting and differentiation within the parent body, followed by mixing of silicate and metal while both were relatively hot. Netschadvo and Watson may have formed by this same process or by impact mixing about 4.5 Gyr ago, but their isotopic ages were

Biomonitoring of Environmental Status and Trends (BEST) Program: Environmental contaminants and their effects on fish in the Columbia River Basin

USGS Publications Warehouse

Hinck, Jo Ellen; Schmitt, Christopher J.; Bartish, Timothy M.; Denslow, Nancy D.; Blazer, Vicki; Anderson, Patrick J.; Coyle, James J.; Dethloff, Gail M.; Tillitt, Donald E.

2004-01-01

Common carp (Cyprinus carpio), black basses (Micropterus sp.), and largescale sucker (Catostomus macrocheilus) together accounted for 80% of the fish sampled during the study. Fish were weighed and measured then field-examined for external and internal lesions, and liver, spleen, and gonads were weighed to compute somatic indices. Selected tissues and fluids were obtained and preserved for analysis of fish health and reproductive biomarkers. Composite samples of whole fish from each station were grouped by species and gender and analyzed for persistent organic and inorganic contaminants and for dioxin-like activity using H4IIE rat hepatoma cell bioassay.

Recent advances in live cell imaging of hepatoma cells

PubMed Central

2014-01-01

Live cell imaging enables the study of dynamic processes of living cells in real time by use of suitable reporter proteins and the staining of specific cellular structures and/or organelles. With the availability of advanced optical devices and improved cell culture protocols it has become a rapidly growing research methodology. The success of this technique relies mainly on the selection of suitable reporter proteins, construction of recombinant plasmids possessing cell type specific promoters as well as reliable methods of gene transfer. This review aims to provide an overview of the recent developments in the field of marker proteins (bioluminescence and fluorescent) and methodologies (fluorescent resonance energy transfer, fluorescent recovery after photobleaching and proximity ligation assay) employed as to achieve an improved imaging of biological processes in hepatoma cells. Moreover, different expression systems of marker proteins and the modes of gene transfer are discussed with emphasis on the study of lipid droplet formation in hepatocytes as an example. PMID:25005127

Ethanolic Extract of Agaricus blazei Fermentation Product Inhibits the Growth and Invasion of Human Hepatoma HA22T/VGH and SK-Hep-1 Cells

PubMed Central

Tung, Yen-Chen; Su, Zheng-Yuan; Kuo, Min-Liang; Sheen, Lee-Yan

2012-01-01

Hepatoma is a leading cause of death in the world. SK-Hep-1 and HA22T/VGH cells are poorly differentiated human hepatocellular carcinoma cell lines with invasive and migratory abilities. Agaricus blazei (AB) is a mushroom with many biological effects and active ingredients, and the ethanolic extract of AB fermentation product (AB-pE) was demonstrated to inhibit the growth of hepatoma Hep3B and HepG2 cells in our previous study. In this study, we further investigated the anticancer and anti-invasive abctivities of the AB-pE. Results showed that the AB-pE inhibited the growth of SK-Hep1 and HA22T/VGH cells (with IC50 values of 26.8 and 28.7 μg/mL, respectively) and led cells toward apoptosis after 48 h of treatment. Activation of caspase-3 by AB-pE (12.5~200 μg/mL) in a dose-dependent manner was observed in both cell lines using fluorescence microscopy and flow cytometry. The apoptosis triggered by the AB-pE was regulated by the increased expression of Bax, the activation of caspase-3, caspase-9, and PARP, and the decreased expression of Bcl-2. Additionally, the AB-pE showed the potential ability to inhibit invasion of SK-Hep1 and HA22T/VGH cells according to the results of a Matrigel invasion assay. Our results suggested that the AB-pE may be a further developed for its potential against hepatoma due to its antiproliferative (via apoptosis) and anti-invasive activities in hepatoma cells. PMID:24716127

Knockdown of hepatoma-derived growth factor-related protein-3 induces apoptosis of H1299 cells via ROS-dependent and p53-independent NF-κB activation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yun, Hong Shik; Department of Life Science, College of Natural Sciences, Hanyang University, Seoul 133-791; Baek, Jeong-Hwa

2014-07-11

Highlights: • HRP-3 is a radiation- and anticancer drug-responsive protein in H1299 cells. • Depletion of HRP-3 induces apoptosis of radio- and chemoresistant H1299 cells. • Depletion of HRP-3 promotes ROS generation via inhibition of the Nrf2/HO-1 pathway. • ROS generation enhances NF-κB activity, which acts as an upstream signal in the c-Myc/Noxa apoptotic pathway. - Abstract: We previously identified hepatoma-derived growth factor-related protein-3 (HRP-3) as a radioresistant biomarker in p53 wild-type A549 cells and found that p53-dependent induction of the PUMA pathway was a critical event in regulating the radioresistant phenotype. Here, we found that HRP-3 knockdown regulates themore » radioresistance of p53-null H1299 cells through a distinctly different molecular mechanism. HRP-3 depletion was sufficient to cause apoptosis of H1299 cells by generating substantial levels of reactive oxygen species (ROS) through inhibition of the Nrf2/HO-1 antioxidant pathway. Subsequent, ROS-dependent and p53-independent NF-κB activation stimulated expression of c-Myc and Noxa proteins, thereby inducing the apoptotic machinery. Our results thus extend the range of targets for the development of new drugs to treat both p53 wild-type or p53-null radioresistant lung cancer cells.« less

Cell damage of hepatoma-22 cells exposed to continuous wave ultrasound.

PubMed

Wang, Pan; Wang, Xiaobing; Liu, Quanhong

2012-01-01

The cellular response of hepatoma-22 cells to ultrasonic irradiation and the potential cause for the action were evaluated. Hepatoma-22 cells were subjected to ultrasound irradiation at a frequency of 2.17 MHz and a spatial average intensity of 1.6 W/cm2 for variable periods of time, and several biological parameters were analyzed. The terephthalic acid (TA) dosimetry method was used to evaluate the efficacies of irradiation parameters on the acoustic cavitation activity by monitoring hydroxyl radical (OH) production. Lactate dehydrogenase (LDH) leakage was assayed to investigate cell membrane integrity. The polarization value of fluorescent probe 1,6-diphenyl-1,3,5-hexatriene (DPH) was measured to monitor plasma membrane fluidity. The malonaldehyde content in cells was determined to reflect lipid peroxidation. Trypan blue exclusion was used to detect cell viability. Additionally, electron microscopy was used to observe morphological changes. The generation of intracellular reactive oxygen species, mitochondria swelling and the loss of mitochondria membrane potential were also investigated. The results showed that 1) the concentration of ·OH production by ultrasonic irradiation in air-saturated cell suspensions increased as ultrasound exposure time increased; 2) compared with control, lactate dehydrogenase leakage, the polarization value of 1,6-diphenyl-1,3,5-hexatriene, malonaldehyde content and cell lysis were significantly elevated when cells were treated by ultrasound for 60 s; 3) cytotoxicity by ultrasound irradiation was also accompanied by an increase in production of intracellular reactive oxygen species and dissipation of mitochondria membrane potential as well as by mitochondria swelling. Presently available information indicates that the plasma membrane and mitochondria are the main targets for ultrasound treatment, and free radicals formation such as ·OH due to ultrasound cavitation may play an important role in mediating these cellular response

Berberine Suppresses Cyclin D1 Expression through Proteasomal Degradation in Human Hepatoma Cells.

PubMed

Wang, Ning; Wang, Xuanbin; Tan, Hor-Yue; Li, Sha; Tsang, Chi Man; Tsao, Sai-Wah; Feng, Yibin

2016-11-15

The aim of this study is to explore the underlying mechanism on berberine-induced Cyclin D1 degradation in human hepatic carcinoma. We observed that berberine could suppress both in vitro and in vivo expression of Cyclin D1 in hepatoma cells. Berberine exhibits dose- and time-dependent inhibition on Cyclin D1 expression in human hepatoma cell HepG2. Berberine increases the phosphorylation of Cyclin D1 at Thr286 site and potentiates Cyclin D1 nuclear export to cytoplasm for proteasomal degradation. In addition, berberine recruits the Skp, Cullin, F-box containing complex-β-Transducin Repeat Containing Protein (SCF β-TrCP ) complex to facilitate Cyclin D1 ubiquitin-proteasome dependent proteolysis. Knockdown of β-TrCP blocks Cyclin D1 turnover induced by berberine; blocking the protein degradation induced by berberine in HepG2 cells increases tumor cell resistance to berberine. Our results shed light on berberine's potential as an anti-tumor agent for clinical cancer therapy.

Berberine Suppresses Cyclin D1 Expression through Proteasomal Degradation in Human Hepatoma Cells

PubMed Central

Wang, Ning; Wang, Xuanbin; Tan, Hor-Yue; Li, Sha; Tsang, Chi Man; Tsao, Sai-Wah; Feng, Yibin

2016-01-01

The aim of this study is to explore the underlying mechanism on berberine-induced Cyclin D1 degradation in human hepatic carcinoma. We observed that berberine could suppress both in vitro and in vivo expression of Cyclin D1 in hepatoma cells. Berberine exhibits dose- and time-dependent inhibition on Cyclin D1 expression in human hepatoma cell HepG2. Berberine increases the phosphorylation of Cyclin D1 at Thr286 site and potentiates Cyclin D1 nuclear export to cytoplasm for proteasomal degradation. In addition, berberine recruits the Skp, Cullin, F-box containing complex-β-Transducin Repeat Containing Protein (SCFβ-TrCP) complex to facilitate Cyclin D1 ubiquitin-proteasome dependent proteolysis. Knockdown of β-TrCP blocks Cyclin D1 turnover induced by berberine; blocking the protein degradation induced by berberine in HepG2 cells increases tumor cell resistance to berberine. Our results shed light on berberine′s potential as an anti-tumor agent for clinical cancer therapy. PMID:27854312

Toward Streamlined Identification of Dioxin-like Compounds in Environmental Samples through Integration of Suspension Bioassay.

PubMed

Xiao, Hongxia; Brinkmann, Markus; Thalmann, Beat; Schiwy, Andreas; Große Brinkhaus, Sigrid; Achten, Christine; Eichbaum, Kathrin; Gembé, Carolin; Seiler, Thomas-Benjamin; Hollert, Henner

2017-03-21

Effect-directed analysis (EDA) is a powerful strategy to identify biologically active compounds in environmental samples. However, in current EDA studies, fractionation and handling procedures are laborious, consist of multiple evaporation steps, and thus bear the risk of contamination and decreased recoveries of the target compounds. The low resulting throughput has been one of the major bottlenecks of EDA. Here, we propose a high-throughput EDA (HT-EDA) work-flow combining reversed phase high-performance liquid chromatography fractionation of samples into 96-well microplates, followed by toxicity assessment in the micro-EROD bioassay with the wild-type rat hepatoma H4IIE cells, and chemical analysis of bioactive fractions. The approach was evaluated using single substances, binary mixtures, and extracts of sediment samples collected at the Three Gorges Reservoir, Yangtze River, China, as well as the rivers Rhine and Elbe, Germany. Selected bioactive fractions were analyzed by highly sensitive gas chromatography-atmospheric pressure laser ionization-time-of-flight-mass spectrometry. In addition, we optimized the work-flow by seeding previously adapted suspension-cultured H4IIE cells directly into the microplate used for fractionation, which makes any transfers of fractionated samples unnecessary. The proposed HT-EDA work-flow simplifies the procedure for wider application in ecotoxicology and environmental routine programs.

Inhibitory effects of α-pinene on hepatoma carcinoma cell proliferation.

PubMed

Chen, Wei-Qiang; Xu, Bin; Mao, Jian-Wen; Wei, Feng-Xiang; Li, Ming; Liu, Tao; Jin, Xiao-Bao; Zhang, Li-Rong

2014-01-01

Pine needle oil from crude extract of pine needles has anti-tumor effects, but the effective component is not known. In the present study, compounds from a steam distillation extract of pine needles were isolated and characterized. Alpha-pinene was identified as an active anti-proliferative compound on hepatoma carcinoma BEL-7402 cells using the MTT assay. Further experiments showed that α-pinene inhibited BEL-7402 cells by arresting cell growth in the G2/M phase of the cell cycle, downregulating Cdc25C mRNA and protein expression, and reducing cycle dependence on kinase 1(CDK1) activity. Taken together, these findings indicate that α-pinene may be useful as a potential anti-tumor drug.

Fucoxanthin Enhances Cisplatin-Induced Cytotoxicity via NFκB-Mediated Pathway and Downregulates DNA Repair Gene Expression in Human Hepatoma HepG2 Cells

PubMed Central

Liu, Cheng-Ling; Lim, Yun-Ping; Hu, Miao-Lin

2013-01-01

Cisplain, a platinum-containing anticancer drug, has been shown to enhance DNA repair and to inhibit cell apoptosis, leading to drug resistance. Thus, the combination of anticancer drugs with nutritional factors is a potential strategy for improving the efficacy of cisplatin chemotherapy. In this study, we investigated the anti-proliferative effects of a combination of fucoxanthin, the major non-provitamin A carotenoid found in Undaria Pinnatifida, and cisplatin in human hepatoma HepG2 cells. We found that fucoxanthin (1–10 μΜ) pretreatment for 24 h followed by cisplatin (10 μΜ) for 24 h significantly decreased cell proliferation, as compared with cisplatin treatment alone. Mechanistically, we showed that fucoxanthin attenuated cisplatin-induced NFκB expression and enhanced the NFκB-regulated Bax/Bcl-2 mRNA ratio. Cisplatin alone induced mRNA expression of excision repair cross complementation 1 (ERCC1) and thymidine phosphorylase (TP) through phosphorylation of ERK, p38 and PI3K/AKT pathways. However, fucoxanthin pretreatment significantly attenuated cisplatin-induced ERCC1 and TP mRNA expression, leading to improvement of chemotherapeutic efficacy of cisplatin. The results suggest that a combined treatment with fucoxanthin and cisplatin could lead to a potentially important new therapeutic strategy against human hepatoma cells. PMID:23299493

Caveolin-1 Confers Resistance of Hepatoma Cells to Anoikis by Activating IGF-1 Pathway.

PubMed

Tang, Wenqing; Feng, Xuemei; Zhang, Si; Ren, Zhenggang; Liu, Yinkun; Yang, Biwei; lv, Bei; Cai, Yu; Xia, Jinglin; Ge, Ningling

2015-01-01

Anoikis resistance is a prerequisite for hepatocellular carcinoma (HCC) metastasis. The role of Caveolin-1 (CAV1) in anoikis resistance of HCC remains unclear. The oncogenic effect of CAV1 on anchor-independent growth and anoikis resistance was investigated by overexpression and knockdown of CAV1 in hepatoma cells. IGF-1 pathway and its downstream signals were detected by immunoblot analysis. Caveolae invagination and IGF-1R internalization was studied by electron microscopy and (125)I-IGF1 internalization assay, respectively. The role of IGF-1R and tyrosine-14 residue (Y-14) of CAV1 was explored by deletion experiment and mutation experiment, respectively. The correlation of CAV1 and IGF-1R was further examined by immunochemical analysis in 120 HCC specimens. CAV1 could promote anchor-independent growth and anoikis resistance in hepatoma cells. CAV1-overexpression increased the expression of IGF-1R and subsequently activated PI3K/Akt and RAF/MEK/ERK pathway, while CAV1 knockdown showed the opposite effect. The mechanism study revealed that CAV1 facilitated caveolae invagination and (125)I-IGF1 internalization. IGF-1R deletion or Y-14 mutation reversed CAV1 mediated anchor-independent growth and anoikis resistance. In addition, CAV1 expression was positively related to IGF-1R expression in human HCC tissues. CAV1 confers resistance of hepatoma cells to anoikis by activating IGF-1 pathway, providing a potential therapeutic target for HCC metastasis. © 2015 S. Karger AG, Basel.

Genotoxicity and induction of DNA damage responsive genes by food-borne heterocyclic aromatic amines in human hepatoma HepG2 cells.

PubMed

Pezdirc, Marko; Žegura, Bojana; Filipič, Metka

2013-09-01

Heterocyclic aromatic amines (HAAs) are potential human carcinogens formed in well-done meats and fish. The most abundant are 2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 2-Amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-Amino-3,4,8-trimethyl-3H-imidazo[4,5-f]quinoxaline (4,8-DiMeIQx) and 2-Amino-3-methyl-3H-imidazo[4,5-f]quinoline (IQ). HAAs exert genotoxic activity after metabolic transformation by CYP1A enzymes, that is well characterized, however the genomic and intervening responses are not well explored. We have examined cellular and genomic responses of human hepatoma HepG2 cells after 24h exposure to HAAs. Comet assay revealed increase in formation of DNA strand breaks by PhIP, MeIQx and IQ but not 4,8-DiMeIQx, whereas increased formation of micronuclei was not observed. The four HAAs up-regulated expression of genes encoding metabolic enzymes CYP1A1, CYP1A2 and UGT1A1 and expression of TP53 and its downstream regulated genes CDKN1A, GADD45α and BAX. Consistent with the up-regulation of CDKN1A and GADD45α the cell-cycle analysis showed arrest in S-phase by PhIP and IQ, and in G1-phase by 4,8-DiMeIQx and MeIQx. The results indicate that upon exposure to HAAs the cells respond with the cell-cycle arrest, which enables cells to repair the damage or eliminate them by apoptosis. However, elevated expression of BCL2 and down-regulation of BAX may indicate that HAAs could suppress apoptosis meaning higher probability of damaged cells to survive and mutate. Copyright © 2013 Elsevier Ltd. All rights reserved.

Paleomagnetic Evidence for Partial Differentiation of the Silicate-Bearing IIE Iron Meteorite Parent Body

NASA Astrophysics Data System (ADS)

Maurel, C.; Bryson, J. F. J.; Weiss, B. P.; Scholl, A.

2016-12-01

The identification of dozens of petrologically diverse chondritic and achondritic meteoritic groups indicates that a diversity of planetesimals formed in the early solar system. It is commonly thought that planetesimals formed as either unmelted or else fully differentiated bodies, implying that chondrites and achondrites cannot have originated on a single body. However, it has been suggested that partially melted bodies with chondritic crusts and achondritic interiors may also have formed. This alternative proposal is supported by the recent identification of post-accretional remanent magnetization in CV, H chondrites, and also possibly in CM chondrites, which has been interpreted as possible evidence for a core dynamo on their parent bodies. Other piece of evidence suggesting the existence of partially differentiated bodies is the existence of the silicate-bearing IIE iron meteorites. The IIEs are composed of a Fe-Ni alloy matrix containing a mixture of chondritic, primitive achondritic, and chondritic silicate inclusions that likely formed on a single parent body. Therefore, IIEs may sample all three putative layers of a layered, partially differentiated body. On the other hand, the siderophile element compositions of the matrix metal demonstrate that it is not the product of fractional crystallization of a molten core. This suggests that the matrix metal is derived from isolated reservoirs of metal in the mantle and/or crust. It is unknown whether a large-scale metallic core, not represented by known meteorite samples, also formed on the same parent planetesimal. We can search for evidence of a molten, advecting core by assessing whether IIE irons contain remanent magnetization produced by a core dynamo. With this goal, we studied the paleomagnetism of a cloudy zone (CZ) interface in the Fe-Ni matrix of the IIE iron Colomera using X-ray photoelectron emission microscopy (XPEEM). Our initial results suggest that a steady, intense magnetic field was present

Paleomagnetic Evidence for Partial Differentiation of the Silicate-Bearing IIE Iron Meteorite Parent Body

NASA Astrophysics Data System (ADS)

Maurel, C.; Bryson, J. F. J.; Weiss, B. P.; Scholl, A.

2017-12-01

The identification of dozens of petrologically diverse chondritic and achondritic meteoritic groups indicates that a diversity of planetesimals formed in the early solar system. It is commonly thought that planetesimals formed as either unmelted or else fully differentiated bodies, implying that chondrites and achondrites cannot have originated on a single body. However, it has been suggested that partially melted bodies with chondritic crusts and achondritic interiors may also have formed. This alternative proposal is supported by the recent identification of post-accretional remanent magnetization in CV, H chondrites, and also possibly in CM chondrites, which has been interpreted as possible evidence for a core dynamo on their parent bodies. Other piece of evidence suggesting the existence of partially differentiated bodies is the existence of the silicate-bearing IIE iron meteorites. The IIEs are composed of a Fe-Ni alloy matrix containing a mixture of chondritic, primitive achondritic, and chondritic silicate inclusions that likely formed on a single parent body. Therefore, IIEs may sample all three putative layers of a layered, partially differentiated body. On the other hand, the siderophile element compositions of the matrix metal demonstrate that it is not the product of fractional crystallization of a molten core. This suggests that the matrix metal is derived from isolated reservoirs of metal in the mantle and/or crust. It is unknown whether a large-scale metallic core, not represented by known meteorite samples, also formed on the same parent planetesimal. We can search for evidence of a molten, advecting core by assessing whether IIE irons contain remanent magnetization produced by a core dynamo. With this goal, we studied the paleomagnetism of a cloudy zone (CZ) interface in the Fe-Ni matrix of the IIE iron Colomera using X-ray photoelectron emission microscopy (XPEEM). Our initial results suggest that a steady, intense magnetic field was present

Toxicological and chemical investigation of untreated municipal wastewater: Fraction- and species-specific toxicity.

PubMed

Hrubik, Jelena; Glisic, Branka; Tubic, Aleksandra; Ivancev-Tumbas, Ivana; Kovacevic, Radmila; Samardzija, Dragana; Andric, Nebojsa; Kaisarevic, Sonja

2016-05-01

Absence of a municipal wastewater (WW) treatment plant results in the untreated WW discharge into the recipient. The present study investigated toxic effects and chemical composition of water extracts and fractions from untreated WW and recipient Danube River (DR). Samples were prepared by solid-phase extraction and silica gel fractionation and screened for EROD activity and cytotoxicity using aquatic models, comprising of fish liver cells (PLHC-1) and a model of the early development of zebrafish embryos, while rat (H4IIE) and human (HepG2) hepatoma cells served as mammalian models. Polar fraction caused cytotoxicity and increased the EROD activity in PLHC-1 cells, and increased mortality and developmental abnormalities in developing zebrafish embryos. In H4IIE, polar fraction induced inhibition of cell growth and increased EROD activity, whereas HepG2 exerted low or no response to the exposure. Non-polar and medium-polar fractions were ineffective. Tentative identification by GC/MS showed that WW is characterized by the hydrocarbons, alkylphenols, plasticizers, and a certain number of benzene derivatives and organic acids. In DR, smaller number of organic compounds was identified and toxicity was less pronounced than in WW treatments. The present study revealed the potent toxic effect of polar fraction of untreated WW, with biological responses varying in sensitivity across organisms. Obtained results confirmed that fraction- and species-specific toxicity should be considered when assessing health risk of environmental pollution. Copyright © 2016 Elsevier Inc. All rights reserved.

Assessing the ecological risk of soil irrigated with wastewater using in vitro cell bioassays.

PubMed

Yu, Guo; Xiao, Ruiyang; Wang, Donghong; Zhou, Jun; Wang, Zijian

2008-12-01

In the most recent research work, the accumulation of toxicants in soil was always assessed through concentration level of the target contaminants. However, assessments based on chemical analysis were limited in numbers and in their unpredictable bioavailability. An alternative assessment could be based on toxicity assessment. It means that a screening bioassay is a necessary tool for identifying and defining contaminants at the sites, which should warrant further attention. In the present study, three in vitro cell bioassays, including the SOS/umu bioassay for genotoxic effects, human estrogen receptor recombinant yeast bioassay for estrogenic effects, and ethoxyresorfin O-deethylase (EROD) with H4IIE rat hepatoma cells bioassay for Ah-receptor agonistic effects, were used for the evaluation of the accumulation of toxicants in soils irrigated with wastewater in the suburb of Beijing, China. The results indicated that there were significant increases of genotoxic, estrogenic, and Ah-receptor agonistic effects in soils irrigated with wastewater, as compared with soils irrigated with groundwater. There was the decreased effect gradient following the increase of the distances from the inlet of the wastewater. It was concluded that wastewater irrigation could cause accumulation of genotoxic, estrogenic, and Ah-receptor agonistic chemicals in soil.

Analysis of the cytotoxicity of carbon-based nanoparticles, diamond and graphite, in human glioblastoma and hepatoma cell lines.

PubMed

Zakrzewska, Karolina Ewa; Samluk, Anna; Wierzbicki, Mateusz; Jaworski, Sławomir; Kutwin, Marta; Sawosz, Ewa; Chwalibog, André; Pijanowska, Dorota Genowefa; Pluta, Krzysztof Dariusz

2015-01-01

Nanoparticles have attracted a great deal of attention as carriers for drug delivery to cancer cells. However, reports on their potential cytotoxicity raise questions of their safety and this matter needs attentive consideration. In this paper, for the first time, the cytotoxic effects of two carbon based nanoparticles, diamond and graphite, on glioblastoma and hepatoma cells were compared. First, we confirmed previous results that diamond nanoparticles are practically nontoxic. Second, graphite nanoparticles exhibited a negative impact on glioblastoma, but not on hepatoma cells. The studied carbon nanoparticles could be a potentially useful tool for therapeutics delivery to the brain tissue with minimal side effects on the hepatocytes. Furthermore, we showed the influence of the nanoparticles on the stable, fluorescently labeled tumor cell lines and concluded that the labeled cells are suitable for drug cytotoxicity tests.

Hypoxia/hepatoma dual specific suicide gene expression plasmid delivery using bio-reducible polymer for hepatocellular carcinoma therapy.

PubMed

Kim, Hyun Ah; Nam, Kihoon; Lee, Minhyung; Kim, Sung Wan

2013-10-10

Gene therapy is suggested as a promising alternative strategy of hepatocellular carcinoma (HCC, also called hepatoma) therapy. To achieve a successful and safe gene therapy, tight regulation of gene expression is required to minimize side-effects in normal tissues. In this study, we developed a novel hypoxia and hepatoma dual specific gene expression vector. The constructed vectors were transfected into various cell lines using bio-reducible polymer, PAM-ABP. First, pAFPS-Luc or pAFPL-Luc vector was constructed with the alpha-fectoprotein (AFP) promoter and enhancer for hepatoma tissue specific gene expression. Then, pEpo-AFPL-Luc was constructed by insertion of the erythropoietin (Epo) enhancer for hypoxic cancer specific gene expression. In vitro transfection assay showed that pEpo-AFPL-Luc transfected hepatoma cell increased gene expression under hypoxic condition. To confirm the therapeutic effect of dual specific vector, herpes simplex virus thymidine kinase (HSV-TK) gene was introduced for cancer cell killing. The pEpo-AFPL-TK was transfected into hepatoma cell lines in the presence of ganciclovir (GCV) pro-drug. Caspase-3/7, MTT and TUNEL assays elucidated that pEpo-AFPL-TK transfected cells showed significant increasing of death rate in hypoxic hepatoma cells compared to controls. Therefore, the hypoxia/hepatoma dual specific gene expression vector with the Epo enhancer and AFP promoter may be useful for hepatoma specific gene therapy. © 2013.

Veins in Silicates of IIE Iron Mont Dieu II: Melt Migration Caused by Impact?

NASA Astrophysics Data System (ADS)

Van Roosbroek, N.; Debaille, V.; Pittarello, L.; Hecht, L.; Claeys, Ph.

2014-09-01

Mont Dieu II is a ~450kg meteorite classified as IIE iron. The primitive silicate inclusions can be linked to the H-chondrites. Thick metal veins with angular clasts crosscut these inclusions and could point to an impact-melt migration formation.

BWTG3 hepatoma cells can acquire phenylalanine hydroxylase, cystathionine synthase and CPS-I without genetic manipulation, but activation of the silent OTC gene requires cell fusion with hepatocytes.

PubMed

Farmer, A A; Goss, S J

1991-04-01

The mouse hepatoma BWTG3 has been tested for its ability to grow in three different media that select for traits normally expressed in adult liver: homocysteine medium to select for cystathionine synthase (CS), tyrosine-free medium for phenylalanine hydroxylase (PH), and ornithine medium for carbamylphosphate synthetase-I (CPS-I) and ornithine transcarbamylase (OTC). In no case were the cells immediately capable of bulk growth, showing that all these traits were in some degree deficient. However, the cultures in homocysteine medium and in tyrosine-free medium both gave rise, spontaneously, to growing clones with frequencies of approximately 10(-3) and 10(-5), respectively. The deficiencies of CS and PH were accordingly excluded from further study, in view of their inherent instability. In contrast, no colonies ever formed in ornithine medium. Though neither CPS-I nor OTC were detectable in stock BWTG3 cells, it was found that CPS-I was readily inducible by hormones. The deficiency of OTC, however, appeared to be totally stable showing no reversion in response either to hormones or to azacytidine treatment. This deficiency was investigated by fusing the hepatoma to OTC+ liver cells prepared from normal or sparse-fur (spf) mice. Sparse-fur mice were used because their OTC is mutant and has a distinctive pH-dependence. OTC+ hybrids were readily produced, without the need for any specific selection for OTC, and, in one case at least, with only minimal chromosome segregation. In all the OTC+ hybrids made with spf cells, there was clear reactivation of the wild-type, hepatoma-derived OTC gene.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of the Cytotoxicity of Carbon-Based Nanoparticles, Diamond and Graphite, in Human Glioblastoma and Hepatoma Cell Lines

PubMed Central

Wierzbicki, Mateusz; Jaworski, Sławomir; Kutwin, Marta; Sawosz, Ewa; Chwalibog, André; Pijanowska, Dorota Genowefa; Pluta, Krzysztof Dariusz

2015-01-01

Nanoparticles have attracted a great deal of attention as carriers for drug delivery to cancer cells. However, reports on their potential cytotoxicity raise questions of their safety and this matter needs attentive consideration. In this paper, for the first time, the cytotoxic effects of two carbon based nanoparticles, diamond and graphite, on glioblastoma and hepatoma cells were compared. First, we confirmed previous results that diamond nanoparticles are practically nontoxic. Second, graphite nanoparticles exhibited a negative impact on glioblastoma, but not on hepatoma cells. The studied carbon nanoparticles could be a potentially useful tool for therapeutics delivery to the brain tissue with minimal side effects on the hepatocytes. Furthermore, we showed the influence of the nanoparticles on the stable, fluorescently labeled tumor cell lines and concluded that the labeled cells are suitable for drug cytotoxicity tests. PMID:25816103

Coordinated modulation of albumin synthesis and mRNA levels in cultured hepatoma cells by hydrocortisone and cyclic AMP analogs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, P.C.; Papaconstantinou, J.

The treatment of Hepa-2 cells, a permanent mouse hepatoma cell line, for 72 h with hydrocortisone (10/sup -6/ M), N/sup 6/,O/sup 2/-dibutyryl cyclic AMP (10/sup -3/ M), or 8-bromo cyclic AMP(10/sup -3/ M) results in a 2-, 3-, or 4-fold increase, respectively, in rates of synthesis and secretion of mouse serum albumin. Simultaneous treatment with hydrocortisone and N/sup 6/,O/sup 2/-dibutyryl cyclic AMP results in a 10-fold stimulation in these parameters, an effect that is significantly more than additive for the two compounds tested. The number of albumin mRNA sequences, determined by hybridization of total cell RNA to albumin complementary DNA,more » was increased in direct proportion to the increases in albumin synthesis in all experiments. The relative rate of albumin synthesis approaches in vivo levels in cells treated simultaneously with hydrocortisone and N/sup 6/,O/sup 2/-dibutyryl cyclic AMP. We propose that these factors may be necessary to maintain the maximal level of differentiated function in the continuous culture of Hepa-2 cells.« less

Release of overexpressed CypB activates ERK signaling through CD147 binding for hepatoma cell resistance to oxidative stress.

PubMed

Kim, Kiyoon; Kim, Hunsung; Jeong, Kwon; Jung, Min Hyung; Hahn, Bum-Soo; Yoon, Kyung-Sik; Jin, Byung Kwan; Jahng, Geon-Ho; Kang, Insug; Ha, Joohun; Choe, Wonchae

2012-08-01

Cyclophilin, a cytosolic receptor for the immunosuppressive drug cyclosporin A, plays a role in diverse pathophysiologies along with its receptor, CD147. Although the interaction between cyclophilin A and CD147 is well established in inflammatory disease, that of cyclophilin B (CypB) with CD147 has not been fully explored, especially in cancer cell biology, and the exact molecular mechanism underlying such an association is poorly understood. In this study, we first identified high expression levels of CypB in 54 % of hepatocellular carcinoma patient tissues but in only 12.5 % of normal liver tissues. Then, we demonstrated that CypB overexpression protects human hepatoma cells against oxidative stress through its binding to CD147; this protective effect depends on the peptidyl prolyl isomerase activity of CypB. siRNA-mediated knockdown of CypB expression rendered hepatoma cells more vulnerable to ROS-mediated apoptosis. Furthermore, we also determined that a direct interaction between secreted CypB and CD147 regulates the extracellular signal-regulated kinase intracellular signaling pathway and is indispensible for the protective functions of CypB. For the first time, we demonstrated that CypB has an essential function in protecting hepatoma cells against oxidative stress through binding to CD147 and regulating the ERK pathway.

Combined inhibitors of angiogenesis and histone deacetylase: efficacy in rat hepatoma.

PubMed

Ganslmayer, Marion; Zimmermann, Annette; Zopf, Steffen; Herold, Christoph

2011-08-21

To evaluate the antitumoral effect of combined inhibitors of angiogenesis and histone deacetylases in an experimental rat hepatoma model. MH7777A hepatoma cells were injected into the liver of male Buffalo rats. After 7 d treatment with the vascular endothelial growth factor receptor antagonist PTK787/ZK222584 (PTK/ZK), the histone deacetylase inhibitor MS-275, tamoxifen (TAM) and/or retinoic acid was initiated (n ≥ 8 animals/group). Natural tumor development was shown in untreated control groups (control 1 with n = 12, control 2 with n = 8). The control groups were initiated at different time points to demonstrate the stability of the hepatoma model. For documentation of possible side effects, we documented any change in body weight, loss of fur and diarrhea. After 21 d treatment, the rats were euthanized. Main target parameters were tumor size and metastasis rate. Additionally, immunohistochemistry for the proliferating cell nuclear antigen (PCNA) and TdT-mediated dUTP-biotin nick end labeling (TUNEL) assay were performed. The control groups developed large tumor nodules with extrahepatic tumor burden in the lung and abdominal organs (control 1: 6.18 cm(3) ± 4.14 cm(3) and control 2: 8.0 cm(3) ± 4.44 cm(3) 28 d after tumor cell injection). The tumor volume did not differ significantly in the control groups (P = 0.13). As single agents MS-275 and PTK/ZK reduced tumor volume by 58.6% ± 2.6% and 48.7% ± 3.2% vs control group 1, which was significant only for MS-275 (P = 0.025). The combination of MS-275 and PTK/ZK induced a nearly complete and highly significant tumor shrinkage by 90.3% ± 1% (P = 0.005). Addition of TAM showed no further efficacy, while quadruple therapy with retinoic acid increased antitumoral efficacy (tumor reduction by 93 ± 1%) and side effects. PCNA positive cells were not significantly reduced by the single agents, while dual therapy (MS-275 and PTK/ZK) and quadruple therapy reduced the PCNA-positive cell fraction significantly by 9

Formation of the Mont Dieu IIE Non Magmatic Iron Meteorite, and Origin of its Silicate Inclusions

NASA Astrophysics Data System (ADS)

van Roosbroek, N.; Goderis, S.; Debaille, V.; Valley, J. W.; Claeys, Ph.

2012-03-01

Mont Dieu is an IIE nonmagmatic iron meteorite showing primitive features such as preserved chondrules and glass. SEM and geochemical analyses demonstrate that it most likely originated from an H-chondrite parent body impacted by a Fe-Ni projectile.

Watson: A new link in the IIE iron chain

NASA Technical Reports Server (NTRS)

Olsen, Edward; Davis, Andrew; Clarke, Roy S., Jr.; Schultz, Ludolf; Weber, Hartwig W.; Clayton, Robert; Mayeda, Toshiko; Jarosewich, Eugene; Sylvester, Paul; Grossman, Lawrence

1994-01-01

Watson, which was found in 1972 in South Australia, contains the largest single silicate rock mass seen in any known iron meteorite. A comprehensive study has been completed on this unusual meteorite: petrography, metallography, analyses of the silicate inclusion (whole rock chemical analysis, INAA, RNAA, noble gases, and oxygen isotope analysis) and mineral compositions (by electron microprobe and ion microprobe). The whole rock has a composition of an H-chondrite minus the normal H-group metal and troilite content. The oxygen isotope composition is that of the silicates in the IIE iron meteorites and lies along an oxygen isotope fractionation line with the H-group chondrites. Trace elements in the metal confirm Watson is a new IIE iron. Whole rock Watson silicate shows an enrichment in K and P (each approximately 2X H-chondrites). The silicate inclusion has a highly equilibrated igneous (peridotite-like) texture with olivine largely poikilitic within low-Ca pyroxene: olivine (Fa20), opx (Fs17Wo3), capx (Fs9Wo14)(with very fine exsolution lamellae), antiperthite feldspar (An1-3Or5) with less than 1 micron exsolution lamellae (An1-3Or greater than 40), shocked feldspar with altered stoichiometry, minor whitlockite (also a poorly characterized interstitial phosphate-rich phase) and chromite, and only traces of metal and troilite. The individual silicate minerals have normal chondritic REE patterns, but whitlockite has a remarkable REE pattern. It is very enriched in light REE (La is 720X C1, and Lu is 90X C1, as opposed to usual chonditic values of approximately 300X and 100-150X, respectively) with a negative Eu anomaly. The enrichment of whole rock K is expressed both in an unusually high mean modal Or content of the feldspar, Or13, and in the presence of antiperthite.

Cytotoxicity of nitric oxide in Fu5 rat hepatoma cells: evidence for co-operative action with hydrogen peroxide.

PubMed Central

Ioannidis, I; de Groot, H

1993-01-01

The NO-releasing compounds 3-morpholinosydnonimine-N-ethylcarbamide (SIN-1), sodium nitroprusside (SNP) and S-nitroso-N-acetyl-DL-penicillamine (SNAP) mediated a rapid loss of viability of Fu5 rat hepatoma cells. SIN-1 in addition to NO also released the superoxide anion radical (O2-.). Its cytotoxicity, however, was not affected by superoxide dismutase. In contrast, the H2O2-converting enzyme catalase significantly, but not completely, diminished cell damage, indicating participation of H2O2 in the tumoricidal activity of SIN-1. Glucose oxidase (5 m-units/ml), producing similar amounts of H2O2 to 5 mM SIN-1, had no effect on cell viability. When 5 m-units/ml glucose oxidase was added to incubations with 5 mM SNP, which alone initiated cell injury of about 40%, cell damage was significantly increased up to 95%. Similar results were observed with 1 mM SNAP and 20 m-units/ml xanthine oxidase, which mediated cytotoxicity of about 90% when both compounds were added together, compared with 35% and 55% cell injury, respectively, induced by the single compounds. The results indicate that a co-operative action with H2O2 enhances the tumoricidal activity of NO in Fu5 cells. No evidence for an interplay of NO with O2-. in cytotoxicity, e.g. via the peroxynitrite anion (ONOO-), was found. PMID:8257422

Effects of the peroxisome proliferator clofibric acid on superoxide dismutase expression in the human HepG2 hepatoma cell line.

PubMed

Bécuwe, P; Bianchi, A; Keller, J M; Dauça, M

1999-09-15

We examined the effects of clofibric acid, a peroxisome proliferator, on the production of superoxide radicals, on the levels of malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), and on the expression of superoxide dismutases (SODs) in the human HepG2 hepatoma cell line. To this end, HepG2 cells were treated for 1 or 5 days with 0.25, 0.50, or 0.75 mM clofibric acid. The production of superoxide radicals was only enhanced in HepG2 cells exposed for 5 days to the different clofibric acid concentrations. However, this overproduction of superoxide radicals was not accompanied by increased rates of lipid peroxidation, as the MDA and 4-HNE levels did not change significantly. Manganese (Mn) SOD activity was increased when HepG2 cells were treated for 1 day with 0.50 or 0.75 mM clofibric acid. For this duration of treatment, no change was observed in total SOD and copper/zinc (Cu/Zn) SOD activities. For a 5-day treatment, total SOD and MnSOD activities as well as the enzyme apoprotein and MnSOD mRNA levels increased whatever the clofibric acid concentration used. This transcriptional induction of the MnSOD gene was correlated with an activation of the activator protein-1 transcription factor for 1 and 5 days of treatment, but was independent of nuclear factor-kappa B and of peroxisome proliferator-activated receptor. On the other hand, the PP exerted very little effect if any on Cu,ZnSOD expression. In contrast to rodent data, PP treatment of human hepatoma cells induces MnSOD expression.

Synergistic cytotoxicity and mechanism of caffeine and lysozyme on hepatoma cell line HepG2

NASA Astrophysics Data System (ADS)

Yang, Hongchao; Li, Jingjuan; Cui, Lin; Ren, Yanqing; Niu, Liying; Wang, Xinguo; Huang, Yun; Cui, Lijian

2018-03-01

The influences of caffeine, lysozyme and the joint application of them on the hepatoma cell line HepG2 proliferation inhibition and cell apoptosis were observed by 3-(4, 5-dimethyl-2-thiazyl)-2, 5-diphenyl-2H-tetrazolium bromide assay and Hoechst 33342, which showed the proliferation inhibition rate of the joint application on HepG2 cells was 47.21%, significantly higher than caffeine or lysozyme, and the joint application promoted the apoptosis of HepG2 cells obviously. Van't Hoff classical thermodynamics formula, the Föster theory of non-radiation energy transfer and fluorescence phase diagram were used to manifest that the process of lysozyme binding to caffeine followed a two-state model, which was spontaneous at low temperature driven by enthalpy change, and the predominant intermolecular force was hydrogen bonding or Van der Waals force to stabilize caffeine-lysozyme complex with the distance 5.86 nm. The attenuated total reflection-Fourier transform infrared spectra indicated that caffeine decreased the relative contents of α-helix and β-turn, which inferred the structure of lysozyme tended to be "loose". Synchronous fluorescence spectra and ultraviolet spectra supported the above conclusion. The amino acid residues in the cleft of lysozyme were exposed and electropositivity was increased attributing to the loose structure, which were conducive to increasing caffeine concentration on the HepG2 cell surface by electrostatic interaction to show synergistic effect. The great quantities of microvilli on the liver cancer cell membrane surface, is beneficial for the lysozyme-caffeine compound to aggregate on cell surface to increase the concentration of caffeine to play stronger physiological role by electrostatic effect.

Concurrent IMRT and weekly cisplatin followed by GDP chemotherapy in newly diagnosed, stage IE to IIE, nasal, extranodal NK/T-Cell lymphoma.

PubMed

Ke, Q-H; Zhou, S-Q; Du, W; Liang, G; Lei, Y; Luo, F

2014-12-12

On the basis of the benefits of frontline radiation in early-stage, extranodal natural killer (NK)/T-cell lymphoma (ENKTL), we conducted the trial of concurrent chemoradiotherapy (CCRT) followed by three cycles of gemcitabine, dexamethasone and cisplatin (GDP). Thirty-two patients with newly diagnosed, stage IE to IIE, nasal ENKTL received CCRT (that is, all patients received intensity-modulated radiotherapy 56 Gy and cisplatin 30 mg/m(2) weekly, 3-5 weeks). Three cycles of GDP (gemcitabine 1000 mg/m(2) intravenously (i.v.) on days 1 and 8, dexamethasone 40 mg orally on days 1-4 and cisplatin 75 mg/m(2) i.v. on day 1 (GDP), every 21 days as an outpatient were scheduled after CCRT. All patients completed CCRT, which resulted in 100% response that included 24 complete responses (CRs) and eight partial responses. The CR rate after CCRT was 75.0% (that is, 24 of 32 responses). Twenty-eight of the 32 patients completed the planned three cycles of GDP, whereas four patients did not because they withdrew (n = 1) or because they had an infection (n = 3). The overall response rate and the CR rate were 90.6% (that is, 29 of 32 responses) and 84.4% (that is, 27 of 32 responses), respectively. Only two patient experienced grade 3 toxicity during CCRT (nausea), whereas 13 of the 30 patients experienced grade 4 neutropenia. The estimated 3-year overall survival and progression-free rates were 87.50% and 84.38%, respectively. In conclusion, CCRT followed by GDP chemotherapy can be a feasible and effective treatment strategy for stage IE to IIE nasal ENKTL.

Synergistic effects of acyclic retinoid and OSI-461 on growth inhibition and gene expression in human hepatoma cells.

PubMed

Shimizu, Masahito; Suzui, Masumi; Deguchi, Atsuko; Lim, Jin T E; Xiao, Danhua; Hayes, Julia H; Papadopoulos, Kyriakos P; Weinstein, I Bernard

2004-10-01

Hepatoma is one of the most frequently occurring cancers worldwide. However, effective chemotherapeutic agents for this disease have not been developed. Acyclic retinoid, a novel synthetic retinoid, can reduce the incidence of postsurgical recurrence of hepatoma and improve the survival rate. OSI-461, a potent derivative of exisulind, can increase intracellular levels of cyclic GMP, which leads to activation of protein kinase G and induction of apoptosis in cancer cells. In the present study, we examined the combined effects of acyclic retinoid plus OSI-461 in the HepG2 human hepatoma cell line. We found that the combination of as little as 1.0 micromol/L acyclic retinoid and 0.01 micromol/L OSI-461 exerted synergistic inhibition of the growth of HepG2 cells. Combined treatment with low concentrations of these two agents also acted synergistically to induce apoptosis in HepG2 cells through induction of Bax and Apaf-1, reduction of Bcl-2 and Bcl-xL, and activation of caspase-3, -8, and -9. OSI-461 enhanced the G0-G1 arrest caused by acyclic retinoid, and the combination of these agents caused a synergistic decrease in the levels of expression of cyclin D1 protein and mRNA, inhibited cyclin D1 promoter activity, decreased the level of hyperphosphorylated forms of the Rb protein, induced increased cellular levels of the p21(CIP1) protein and mRNA, and stimulated p21(CIP1) promoter activity. Moreover, OSI-461 enhanced the ability of acyclic retinoid to induce increased cellular levels of retinoic acid receptor beta and to stimulate retinoic acid response element-chloramphenicol acetyltransferase activity. A hypothetical model involving concerted effects on p21(CIP1) and retinoic acid receptor beta expression is proposed to explain these synergistic effects. Our results suggest that the combination of acyclic retinoid plus OSI-461 might be an effective regimen for the chemoprevention and chemotherapy of human hepatoma and possibly other malignancies.

Enhanced migration of tissue inhibitor of metalloproteinase overexpressing hepatoma cells is attributed to gelatinases: Relevance to intracellular signaling pathways

PubMed Central

Roeb, Elke; Bosserhoff, Anja-Katrin; Hamacher, Sabine; Jansen, Bettina; Dahmen, Judith; Wagner, Sandra; Matern, Siegfried

2005-01-01

AIM: To study the effect of gelatinases (especially MMP-9) on migration of tissue inhibitor of metalloproteinase (TIMP-1) overexpressing hepatoma cells. METHODS: Wild type HepG2 cells, cells stably transfected with TIMP-1 and TIMP-1 antagonist (MMP-9-H401A, a catalytically inactive matrix metalloproteinase (MMP) which still binds and neutralizes TIMP-1) were incubated in Boyden chambers either with or without Galardin (a synthetic inhibitor of MMP-1, -2, -3, -8, -9) or a specific inhibitor of gelatinases. RESULTS: Compared to wild type HepG2 cells, the cells overexpressing TIMP-1 showed 115% migration (P<0.05) and the cells overexpressing MMP-9-H401A showed 62% migration (P<0.01). Galardin reduced cell migration dose dependently in all cases. The gelatinase inhibitor reduced migration in TIMP-1 overexpressing cells predominantly. Furthermore, we examined intracellular signal transduction pathways of TIMP-1-dependent HepG2 cells. TIMP-1 deactivates cell signaling pathways of MMP-2 and MMP-9 involving p38 mitogen-activated protein kinase. Specific blockade of the ERK pathway suppresses gelatinase expression either in the presence or absence of TIMP-1. CONCLUSION: Overexpressing functional TIMP-1- enhanced migration of HepG2-TIMP-1 cells depends on enhanced MMP-activity, especially MMP-9. PMID:15754388

Specific gene transfer mediated by galactosylated poly-L-lysine into hepatoma cells.

PubMed

Han, J; Il Yeom, Y

2000-07-20

Plasmid DNA/galactosylated poly-L-lysine(GalPLL) complex was used to transfer luciferase reporter gene in vitro into human hepatoma cells by a receptor-mediated endocytosis process. DNA was combined with galPLL via charge interaction (DNA:GalPLL:fusogenic peptide, 1:0.4:5, w/w/w) and the resulting complex was characterized by dynamic light scattering, gel retardation assay and zeta potential analyzer to determine the particle size, electrostatic charge interaction, and apparent surface charge. The complex was tested for the efficiency of gene transfer in cultured human hepatoblastoma cell line Hep G2 and fibroblast cells NIH/3T3 in vitro. The mean diameter of the complex (DNA:GalPLL=1:0.4, w/w) was 256+/-34.8 nm, and at this ratio, it was positively charged (zeta potential of this complex was 10.1 mV). Hep G2 cells, which express a galactose specific membrane lectin, were efficiently and selectively transfected with the RSV Luc/GalPLL complex in a sugar-dependent manner. NIH/3T3 cells, which do not express the galactose-specific membrane lectin, showed only a marginal level of gene expression. The transfection efficiency of GalPLL-conjugated DNA complex into Hep G2 cells was greatly enhanced in the presence of fusogenic peptide that can disrupt endosomes, where the GalPLL-DNA complex is entrapped with the fusogenic peptide. With the fusogenic peptide KALA, the luciferase activity in Hep G2 cells was ten-fold higher than that of cells transfected in the absence of the fusogenic peptide. Our gene transfer formulation may find potential application for the gene therapy of liver diseases.

30Ar-40Ar Ages of Silicates from IIE Iron Meteorites

NASA Astrophysics Data System (ADS)

Garrison, D. H.; Bogard, D. D.

1995-09-01

Several IIE iron meteorites contain small silicate inclusions, dispersed within metal, which suggest formation by a common process involving different degrees of heating and silicate fractionation from a chondrite-like parent (see discussion and references in McCoy [1]). The isotope chronology of IIE meteorites addresses two major questions concerning their origin. How many formation events are required, and do the isotopic ages also represent the times of silicate differentiation in some meteorites, or do they represent later impact heating events? We have determined ^39Ar-^40Ar ages of whole silicate samples of Watson, Techado, and Miles [1]. Although each meteorite gives a complex Ar age spectrum, each spectrum gives a well-defined age plateau over a significant (55-65%) portion of the total ^39Ar release. The ^39Ar-^40Ar degassing ages derived are 3.656 +/-0.005 Ga for Watson, 4.482 +/-0.025 Ga for Techado, and 4.408 +/-0.011 Ga for Miles (one-sigma errors). Absolute ages have an additional ^-0.5% uncertainty arising from the hornblende age monitor used. None of our Ar-Ar spectra show any significant evidence for an age older than those given, and only Miles shows modest evidence for recent diffusive loss of ^40Ar (affecting ^-10% of the ^39Ar release). Previous studies of Kodaikanal gave these ages: Rb-Sr = 3.7 +/-0.1 Ga [2], Pb-Pb = 3.676 +/-0.003 Ga [3], and K-^40Ar = 3.5 Ga [4]. Netschaevo gave a ^39Ar-^40Ar age of 3.74 Ga +/-0.03 Ga [5], and Watson gave a K-^40Ar age of 3.5 Ga [6]. (Some ages have been adjusted for changes in decay and irradiation constants.) All three meteorites suggest a common formation age of ^-3.70 +/-0.05 Ga. The ^39Ar-^40Ar age for Techado is identical to a ^39Ar-^40Ar age of 4.49 +/-0.03 Ga reported for Weekeroo Station [5] and to a Rb-Sr age of 4.51 Ga for Colomera [7]. These ages resemble ^39Ar-^40Ar ages of unshocked ordinary chondrites, and suggest that metal-silicate mixing and cooling to closure for Ar diffusion occurred

[Effect of ERK/AP-1 signaling pathway on proliferation of hepatoma cells induced by PAR-2 agonists].

PubMed

Zheng, Yan-min; Xie, Li-qun; Li, Xuan; Zhao, Jun-yan; Chen, Xiao-yi; Chen, Li; Zhou, Jing; Li, Fei

2009-12-01

To investigate the expression of protease activated receptor-2 (PAR-2) in human HepG2 hepatoma cells and elucidate the effects of trypsin and PAR-2 agonist peptide SLIGKV-NH(2) upon the proliferation of hepatoma cells and its intracellular signaling mechanism. PAR-2 protein and mRNA expression were detected by immunofluorescence and RT-PCR. The cells were treated with SLIGKV-NH(2), trypsin, reverse PAR-2 agonist peptide VKGILS-NH(2) or PD98059. The changes of cell cycle distribution were evaluated by flow cytometry. The proliferative potential of HepG2 cells was estimated by MTT. The changes of PAR-2, c-fos and PCNA mRNA expression were detected by RT-PCR. The changes of c-fos and PCNA protein expression were detected by Western blotting. PAR-2 protein and mRNA were expressed in HepG2 cells. PAR-2 mRNA expression (PAR-2/beta-actin) were 0.70 +/- 0.04 and 0.99 +/- 0.05 respectively in cells treated with trypsin and SLIGKV-NH(2). They were both significantly higher than that in the control group (0.35 +/- 0.05, F = 135.534, P < 0.01). Percent G(0)/G(1) phase of HepG2 cells treated with trypsin or SLIGKV-NH(2) were significantly lower than those in the control group [(56.11 +/- 0.85)%, (57.85 +/- 0.46)% vs (79.12 +/- 0.67)%, both P < 0.01] Percent S phase, G(2)/M phase and proliferation index (PI) of HepG2 cells treated with trypsin or SLIGKV-NH(2) were significantly elevated (P < 0.01). The proliferation-enhancing effects and the up-regulation of mRNA and protein of c-fos and PCNA induced by trypsin or SLIGKV-NH(2) were significantly blocked by pretreatment with PD98059 (P < 0.01). There was no statistical significance in proliferation of HepG2 cells between the reverse PAR-2 agonist peptide VKGILS-NH(2) and control group (P > 0.05). PAR-2 is expressed in HepG2 hepatoma cells. PAR-2 activation induced by trypsin or SLIGKV-NH(2) promotes the proliferation of HepG2 cells partially via the ERK/AP-1 pathway.

AMF/PGI transactivates the MMP-3 gene through the activation of Src-RhoA-phosphatidylinositol 3-kinase signaling to induce hepatoma cell migration.

PubMed

Shih, Wen-Ling; Liao, Ming-Huei; Yu, Feng-Ling; Lin, Ping-Yuan; Hsu, Hsue-Yin; Chiu, Shu-Jun

2008-11-08

We have previously shown that AMF/PGI induces hepatoma cell migration through the induction of MMP-3. This work investigates how AMF/PGI activates the MMP-3 gene. We demonstrated that AMF/PGI transactivates the MMP-3 gene promoter through AP-1. The transactivation and induction of cell migration effect of AMF/PGI directly correlates with its enzymatic activity. Various analyses showed that AMF/PGI stimulated the Src-RhoA-PI3-kinase signaling pathway, and these three signaling molecules could form a complex. Our results demonstrate a new mechanism of AMF/PGI-induced cell migration and a link between Src-RhoA-PI3-kinase, AP-1, MMP-3 and hepatoma cell migration.

[Cytotoxicity of the secondary metabolites of Marine Mangrove Fungus Paecilomyces sp. tree 1-7 on human hepatoma cell line HepG2].

PubMed

Cai, Xiao-Ling; Gao, Jun-Ping; Li, Qing; Wen, Lu; She, Zhi-Gang; Lin, Yong-Cheng

2008-06-01

To study the cytotoxicity of the secondary metabolites of Marine Mangrove Fungus Paecilomyces sp. Tree 1-7 on human hepatoma cell line HepG2 cultured in vitro. Three groups were divided: compounds group, 5-Fu group and control group. The cytotoxicity was measured by MTT method when HepG2 cells were treated by different concentration of the secondary metabolites of Paecilomyces sp. Tree 1-7. Secalonic acid A, tenellic acid A and alternin inhibited the growth of human hepatoma cell line HepG2, the IC50 separately were 2.0, 62.1 and 7.0 microg/ml. Secalonic acid A and alternin have strong cytotoxicity on HepG2 cultured in vitro.

Photocatalytic degradation of 4-amino-6-chlorobenzene-1,3-disulfonamide stable hydrolysis product of hydrochlorothiazide: Detection of intermediates and their toxicity.

PubMed

Armaković, Sanja J; Armaković, Stevan; Četojević-Simin, Dragana D; Šibul, Filip; Abramović, Biljana F

2018-02-01

In this work we have investigated in details the process of degradation of the 4-amino-6-chlorobenzene-1,3-disulfonamide (ABSA), stable hydrolysis product of frequently used pharmaceutical hydrochlorothiazide (HCTZ), as one of the most ubiquitous contaminants in the sewage water. The study encompassed investigation of degradation by hydrolysis, photolysis, and photocatalysis employing commercially available TiO 2 Degussa P25 catalyst. The process of direct photolysis and photocatalytic degradation were investigated under different type of lights. Detailed insights into the reactive properties of HCTZ and ABSA have been obtained by density functional theory calculations and molecular dynamics simulations. Specifically, preference of HCTZ towards hydrolysis was confirmed experimentally and explained using computational study. Results obtained in this study indicate very limited efficiency of hydrolytic and photolytic degradation in the case of ABSA, while photocatalytic degradation demonstrated great potential. Namely, after 240 min of photocatalytic degradation, 65% of ABSA was mineralizated in water/TiO 2 suspension under SSI, while the nitrogen was predominantly present as NH 4 + . Reaction intermediates were studied and a number of them were detected using LC-ESI-MS/MS. This study also involves toxicity assessment of HCTZ, ABSA, and their mixtures formed during the degradation processes towards mammalian cell lines (rat hepatoma, H-4-II-E, human colon adenocarcinoma, HT-29, and human fetal lung, MRC-5). Toxicity assessments showed that intermediates formed during the process of photocatalysis exerted only mild cell growth effects in selected cell lines, while direct photolysis did not affect cell growth. Copyright © 2017 Elsevier Ltd. All rights reserved.

188Re-SSS lipiodol: radiolabelling and biodistribution following injection into the hepatic artery of rats bearing hepatoma.

PubMed

Garin, Etienne; Denizot, Benoit; Noiret, Nicolas; Lepareur, Nicolas; Roux, Jerome; Moreau, Myriam; Herry, Jean-Yves; Bourguet, Patrick; Benoit, Jean-Pierre; Lejeune, Jean-Jacques

2004-10-01

Although intra-arterial radiation therapy with 131I-lipiodol is a useful therapeutic approach to the treatment of hepatocellular carcinoma, various disadvantages limit its use. To describe the development of a method for the labelling of lipiodol with 188Re-SSS (188Re (S2CPh)(S3CPh)2 complex) and to investigate its biodistribution after injection into the hepatic artery of rats with hepatoma. 188Re-SSS lipiodol was obtained after dissolving a chelating agent, previously labelled with 188Re, in cold lipiodol. The radiochemical purity (RCP) of labelling was checked immediately. The 188Re-SSS lipiodol was injected into the hepatic artery of nine rats with a Novikoff hepatoma. They were sacrificed 1, 24 and 48 h after injection, and used for ex vivo counting. Labelling of 188Re-SSS lipiodol was achieved with a yield of 97.3+/-2.1%. The immediate RCP was 94.1+/-1.7%. Ex vivo counting confirmed a predominantly hepatic uptake, with a good tumoral retention of 188Re-SSS lipiodol, a weak pulmonary uptake and a very faint digestive uptake. The 'tumour/non-tumoral liver' ratio was high at 1, 24 and 48 h after injection (2.9+/-1.5, 4.1+/-/4.1 and 4.1+/-0.7, respectively). Using the method described here, 188Re-SSS lipiodol can be obtained with a very high yield and a satisfactory RCP. The biodistribution in rats with hepatoma indicates a good tumoral retention of 188Re-SSS lipiodol associated with a predominant hepatic uptake, a weak pulmonary uptake and a very faint digestive uptake. This product should be considered for intra-arterial radiation therapy in human hepatoma.

INDUCTION OF AN ESTROGEN-RESPONSIVE REPORTER GENE IN RAINBOW TROUT HEPATOMA CELLS (RTH 149) AT 11 OR 18 DEGREES C

EPA Science Inventory

A reporter gene assay in a cultured rainbow trout cell line was used to determine the influence of temperature on the expression of an estrogen-responsive gene. Rainbow trout hepatoma cells (RTH 149) incubated at 11 or 18 degrees C were co-transfected with an estrogen-responsive ...

Thyroid epithelial cell hyperplasia in IFN-gamma deficient NOD.H-2h4 mice.

PubMed

Yu, Shiguang; Sharp, Gordon C; Braley-Mullen, Helen

2006-01-01

The role of inflammatory cells in thyroid epithelial cell (thyrocyte) hyperplasia is unknown. Here, we demonstrate that thyrocyte hyperplasia in IFN-gamma-/- NOD.H-2h4 mice has an autoimmune basis. After chronic exposure to increased dietary iodine, 60% of IFN-gamma-/- mice had severe thyrocyte hyperplasia with minimal or moderate lymphocyte infiltration, and thyroid dysfunction with reduced serum T4. All mice produced anti-thyroglobulin autoantibody. Some wild-type NOD.H-2h4 mice had isolated areas of thyrocyte hyperplasia with predominantly lymphocytic infiltration, whereas IL-4-/- and 50% of wild-type NOD.H-2h4 mice developed lymphocytic thyroiditis but no thyrocyte hyperplasia. Both thyroid infiltrating inflammatory cells and environmental factors (iodine) were required to induce thyrocyte hyperplasia. Splenocytes from IFN-gamma-/- mice with thyrocyte hyperplasia, but not splenocytes from naïve IFN-gamma-/- mice, induced hyperplasia in IFN-gamma-/- NOD.H-2h4.SCID mice. These results may provide clues for understanding the mechanisms underlying development of epithelial cell hyperplasia not only in thyroids but also in other tissues and organs.

Inhibition of glutathione synthesis eliminates the adaptive response of ascitic hepatoma 22 cells to nedaplatin that targets thioredoxin reductase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Yijun; Lu, Hongjuan; Wang, Dongxu

2012-12-15

Thioredoxin reductase (TrxR) is a target for cancer therapy and the anticancer mechanism of cisplatin involves TrxR inhibition. We hypothesize that the anticancer drug nedaplatin (NDP), an analogue of cisplatin and a second-generation platinum complex, also targets TrxR. Furthermore, we investigate whether the therapeutic efficacy of NDP can be enhanced by simultaneous modulation of 1) TrxR, via NDP, and 2) glutathione (GSH), via the GSH synthesis inhibitor buthionine sulfoximine (BSO). Mice bearing ascitic hepatoma 22 (H22) cells were treated with NDP alone or NDP plus BSO. TrxR activity of H22 cells was inhibited by NDP in a dose-dependent manner. Amore » high correlation between the inhibition of TrxR activity at 6 h and the inhibition of ascitic fluid volume at 72 h was established (r = 0.978, p < 0.01). As an adaptive response, the viable ascitic cancer cells after NDP treatment displayed an enlarged cell phenotype, assembled with several-fold more antioxidant enzymes and GSH-predominant non-protein free thiols. This adaptive response was largely eliminated when BSO was co-administered with NDP, leading to the decimation of the H22 cell population without enhancing renal toxicity, since at this dose, NDP did not inhibit renal TrxR activity. In conclusion, the pharmacological effect of NDP involves TrxR inhibition, and the adaptive response of NDP-treated ascitic H22 cells can be efficiently counteracted by BSO. Simultaneous modulation of TrxR and GSH on ascitic H22 cells using NDP plus BSO greatly enhances therapeutic efficacy as compared with the single modulation of TrxR using NDP alone. -- Highlights: ► Nedaplatin at a pharmacological dose inhibits TrxR in cancer cells but not in kidney. ► The nedaplatin-treated cancer cells exhibit adaptive response. ► Buthionine sulfoximine inhibits glutathione in both cancer cells and kidney. ► Buthionine sulfoximine counteracts the adaptive response to the nedaplatin treatment. ► Buthionine sulfoximine does

Hepatoma targeting peptide conjugated bio-reducible polymer complexed with oncolytic adenovirus for cancer gene therapy

PubMed Central

Choi, Joung-Woo; Kim, Hyun Ah; Nam, Kihoon; Na, Youjin; Yun, Chae-Ok; Kim, SungWan

2015-01-01

Despite adenovirus (Ad) vector’s numerous advantages for cancer gene therapy, such as high ability of endosomal escape, efficient nuclear entry mechanism, and high transduction, and therapeutic efficacy, tumor specific targeting and antiviral immune response still remain as a critical challenge in clinical setting. To overcome these obstacles and achieve cancer-specific targeting, we constructed tumor targeting bioreducible polymer, an arginine grafted bio-reducible polymer (ABP)-PEG-HCBP1, by conjugating PEGylated ABP with HCBP1 peptides which has high affinity and selectivity towards hepatoma. The ABP-PEG-HCBP1-conjugated replication incompetent GFP-expressing ad, (Ad/GFP)-ABP-PEG-HCBP1, showed a hepatoma cancer specific uptake and transduction compared to either naked Ad/GFP or Ad/GFP-ABP. Competition assays demonstrated that Ad/GFP-ABP-PEG-HCBP1-mediated transduction was specifically inhibited by HCBP1 peptide rather than coxsackie and adenovirus receptor specific antibody. In addition, ABP-PEG-HCBP1 can protect biological activity of Ad against serum, and considerably reduced both innate and adaptive immune response against Ad. shMet-expressing oncolytic Ad (oAd; RdB/shMet) complexed with ABP-PEG-HCBP1 delivered oAd efficiently into hepatoma cancer cells. The oAd/ABP-PEG-HCBP1 demonstrated enhanced cancer cell killing efficacy in comparison to oAd/ABP complex. Furthermore, Huh7 and HT1080 cancer cells treated with oAd/shMet-ABP-PEG-HCBP1 complex had significantly decreased Met and VEGF expression in hepatoma cancer, but not in non-hepatoma cancer. In sum, these results suggest that HCBP1-conjugated bioreducible polymer could be used to deliver oncolytic Ad safely and efficiently to treat hepatoma. PMID:26437261

Mineralogy and Ar-Ar Age of the Tarahumara IIE Iron, with Reference to the Origin of Alkali-Rich Materials

NASA Technical Reports Server (NTRS)

Takeda, Hiroshi; Bogard, Donald D.; Otsuki, Mayumi; Ishii, Teruaki

2003-01-01

Silicate inclusions in nine known IIE irons show diversity in mineralogy, and Colomera, Kodaikanal, Elga and Miles contain alkali-rich silicate inclusions. Bogard et al. showed evidence of a complex parent body evolution for IIE irons based on Ar-39-Ar-40 ages. Colomera contained a sanidine-rich surface inclusion and the K-enrichment trends in the Na-rich inclusions are different from those of other IIEs. To elucidate the origin of K-rich materials, we studied the mineralogy and Ar-Ar age of silicate inclusions from the Tarahumara IIE iron meteorite.

Let-7c overexpression inhibits dengue virus replication in human hepatoma Huh-7 cells.

PubMed

Escalera-Cueto, Manuel; Medina-Martínez, Ingrid; del Angel, Rosa M; Berumen-Campos, Jaime; Gutiérrez-Escolano, Ana Lorena; Yocupicio-Monroy, Martha

2015-01-22

MicroRNAs (miRNAs) constitute an important class of non-coding RNA implicated in gene expression regulation. More than 1900 miRNA molecules have been identified in humans and their modulation during viral infection and it is recognized to play a role in latency regulation or in establishing an antiviral state. The liver cells are targets during DENV infection, and alteration of liver functions contributes to severe disease. In this work the miRNAs expression profile of the human hepatoma cell line, Huh-7, infected with DENV-2 was determined using microarray and real-time PCR. Let-7c is one of the miRNAs up-regulated during DENV infection in the hepatic Huh-7 as well as in the macrophage-monocytic cell line U937-DC-SIGN. Let-7c overexpression down-regulates both DENV-2 and DENV-4 infection. Additionally, we found that the transcription factor BACH1, a let-7c target, is also down-regulated during DENV infection. In accordance with this finding, HO-1, the main responsive factor of BACH1 was found up-regulated. The up-regulation of HO-1 may contribute to the stress oxidative response in infected cells. Copyright © 2014 Elsevier B.V. All rights reserved.

The oncoprotein HBXIP suppresses gluconeogenesis through modulating PCK1 to enhance the growth of hepatoma cells.

PubMed

Shi, Hui; Fang, Runping; Li, Yinghui; Li, Leilei; Zhang, Weiying; Wang, Huawei; Chen, Fuquan; Zhang, Shuqin; Zhang, Xiaodong; Ye, Lihong

2016-11-28

Hepatitis B X-interacting protein (HBXIP) as an oncoprotein plays crucial roles in the development of cancer, involving glucose metabolism reprogramming. In this study, we are interested in whether the oncoprotein HBXIP is involved in the modulation of gluconeogenesis in liver cancer. Here, we showed that the expression level of phosphoenolpyruvate carboxykinase (PCK1), a key enzyme of gluconeogenesis, was lower in clinical hepatocellular carcinoma (HCC) tissues than that in normal tissues. Mechanistically, HBXIP inhibited the expression of PCK1 through down-regulating transcription factor FOXO1 in hepatoma cells, and up-regulated miR-135a targeting the 3'UTR of FOXO1 mRNA in the cells. In addition, HBXIP increased the phosphorylation levels of FOXO1 protein by activating PI3K/Akt pathway, leading to the export of FOXO1 from nucleus to cytoplasm. Strikingly, over-expression of PCK1 could abolish the HBXIP-promoted growth of hepatoma cells in vitro and in vivo. Thus, we conclude that the oncoprotein HBXIP is able to depress the gluconeogenesis through suppressing PCK1 to promote hepatocarcinogenesis, involving miR-135a/FOXO1 axis and PI3K/Akt/p-FOXO1 pathway. Our finding provides new insights into the mechanism by which oncoprotein HBXIP modulates glucose metabolism reprogramming in HCC. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Hepatitis C virus Core overcomes all-trans retinoic acid-induced apoptosis in human hepatoma cells by inhibiting p14 expression via DNA methylation

PubMed Central

Kwak, Juri; Choi, Jung-Hye; Jang, Kyung Lib

2017-01-01

All-trans retinoic acid (ATRA), the most biologically active metabolite of vitamin A, is known to induce p14 expression via promoter hypomethylation to activate the p14-MDM2-p53 pathway, which leads to activation of the p53-dependent apoptotic pathway and subsequent induction of apoptosis in human hepatoma cells. In the present study, we found that hepatitis C virus (HCV) Core derived from ectopic expression or HCV infection overcomes ATRA-induced apoptosis in p53-positive hepatoma cells. For this effect, HCV Core upregulated both protein levels and enzyme activities of DNA methyltransferase 1 (DNMT1), DNMT3a, and DNMT3b and thereby repressed p14 expression via promoter hypermethylation, resulting in inactivation of the pathway leading to p53 accumulation in the presence of ATRA. As a result, HCV Core prevented ATRA from activating several apoptosis-related molecules, including Bax, p53 upregulated modulator of apoptosis, caspase-9, caspase-3, and poly (ADP-ribose) polymerase. In addition, complementation of p14 in the Core-expressing cells by either ectopic expression or treatment with 5-Aza-2′dC almost completely abolished the potential of HCV Core to suppress ATRA-induced apoptosis. Based on these observations, we conclude that HCV Core executes its oncogenic potential by suppressing the p53-dependent apoptosis induced by ATRA in human hepatoma cells. PMID:29156743

Hepatoma targeting peptide conjugated bio-reducible polymer complexed with oncolytic adenovirus for cancer gene therapy.

PubMed

Choi, Joung-Woo; Kim, Hyun Ah; Nam, Kihoon; Na, Youjin; Yun, Chae-Ok; Kim, SungWan

2015-12-28

Despite adenovirus (Ad) vector's numerous advantages for cancer gene therapy, such as high ability of endosomal escape, efficient nuclear entry mechanism, and high transduction, and therapeutic efficacy, tumor specific targeting and antiviral immune response still remain as a critical challenge in clinical setting. To overcome these obstacles and achieve cancer-specific targeting, we constructed tumor targeting bioreducible polymer, an arginine grafted bio-reducible polymer (ABP)-PEG-HCBP1, by conjugating PEGylated ABP with HCBP1 peptides which has high affinity and selectivity towards hepatoma. The ABP-PEG-HCBP1-conjugated replication incompetent GFP-expressing ad, (Ad/GFP)-ABP-PEG-HCBP1, showed a hepatoma cancer specific uptake and transduction compared to either naked Ad/GFP or Ad/GFP-ABP. Competition assays demonstrated that Ad/GFP-ABP-PEG-HCBP1-mediated transduction was specifically inhibited by HCBP1 peptide rather than coxsackie and adenovirus receptor specific antibody. In addition, ABP-PEG-HCBP1 can protect biological activity of Ad against serum, and considerably reduced both innate and adaptive immune response against Ad. shMet-expressing oncolytic Ad (oAd; RdB/shMet) complexed with ABP-PEG-HCBP1 delivered oAd efficiently into hepatoma cancer cells. The oAd/ABP-PEG-HCBP1 demonstrated enhanced cancer cell killing efficacy in comparison to oAd/ABP complex. Furthermore, Huh7 and HT1080 cancer cells treated with oAd/shMet-ABP-PEG-HCBP1 complex had significantly decreased Met and VEGF expression in hepatoma cancer, but not in non-hepatoma cancer. In sum, these results suggest that HCBP1-conjugated bioreducible polymer could be used to deliver oncolytic Ad safely and efficiently to treat hepatoma. Copyright © 2015 Elsevier B.V. All rights reserved.

Insulin stimulates the expression of the SHARP-1 gene via multiple signaling pathways.

PubMed

Takagi, K; Asano, K; Haneishi, A; Ono, M; Komatsu, Y; Yamamoto, T; Tanaka, T; Ueno, H; Ogawa, W; Tomita, K; Noguchi, T; Yamada, K

2014-06-01

The rat enhancer of split- and hairy-related protein-1 (SHARP-1) is a basic helix-loop-helix transcription factor. An issue of whether SHARP-1 is an insulin-inducible transcription factor was examined. Insulin rapidly increased the level of SHARP-1 mRNA both in vivo and in vitro. Then, signaling pathways involved with the increase of SHARP-1 mRNA by insulin were determined in H4IIE rat hepatoma cells. Pretreatments with LY294002, wortmannin, and staurosporine completely blocked the induction effect, suggesting the involvement of both phosphoinositide 3-kinase (PI 3-K) and protein kinase C (PKC) pathways. In fact, overexpression of a dominant negative form of atypical protein kinase C lambda (aPKCλ) significantly decreased the induction of the SHARP-1 mRNA. In addition, inhibitors for the small GTPase Rac or Jun N-terminal kinase (JNK) also blocked the induction of SHARP-1 mRNA by insulin. Overexpression of a dominant negative form of Rac1 prevented the activation by insulin. Furthermore, actinomycin D and cycloheximide completely blocked the induction of SHARP-1 mRNA by insulin. Finally, when a SHARP-1 expression plasmid was transiently transfected with various reporter plasmids into H4IIE cells, the promoter activity of PEPCK reporter plasmid was specifically decreased. Thus, we conclude that insulin induces the SHARP-1 gene expression at the transcription level via a both PI 3-K/aPKCλ/JNK- and a PI 3-K/Rac/JNK-signaling pathway; protein synthesis is required for this induction; and that SHARP-1 is a potential repressor of the PEPCK gene expression. © Georg Thieme Verlag KG Stuttgart · New York.

Biomonitoring of Environmental Status and Trends (BEST) Program: Environmental contaminants and their effects on fish in the Yukon River Basin

USGS Publications Warehouse

Hinck, Jo Ellen; Bartish, Timothy M.; Blazer, Vicki; Denslow, Nancy D.; Gross, Tim S.; Myers, Mark S.; Anderson, Patrick J.; Orazio, Carl E.; Tillitt, Donald E.

2004-01-01

This project collected, examined, and analyzed 217 fish representing three species at 10 stations in the U.S. portion of the Yukon River Basin (YRB) from May to October 2002. Four sampling sites were located on the Yukon River; two were located on the Porcupine River, and one site was on each of the Ray, Tanana, Tolavana, and Innoko Rivers. Norther pike (Esox lucius), longnose sucker (Catostomus catostomus), and burbot (Lota lota) were weighed and measured, and examined in the field for external and internal lesions, and liver, spleen, and gonads were weighed to compute somatic indices. Selected tissues and fluids were collected and preserved for analysis of fish health and reproductive biomarkers. Composite samples of whole fish from each station were grouped by species and gender and analyzed for organochlorines and elemental contaminants and for dioxin-like activity using H4IIE rat hepatoma cell bioassay.

First finding of impact melt in the IIE Netschaëvo meteorite

NASA Astrophysics Data System (ADS)

Roosbroek, N.; Pittarello, L.; Greshake, A.; Debaille, V.; Claeys, P.

2016-02-01

About half of the IIE nonmagmatic iron meteorites contain silicate inclusions with a primitive to differentiated nature. The presence of preserved chondrules has been reported for two IIE meteorites so far, Netschaëvo and Mont Dieu, which represent the most primitive silicate material within this group. In this study, silicate inclusions from two samples of Netschaëvo were examined. Both silicate inclusions are characterized by a porphyritic texture dominated by clusters of coarse-grained olivine and pyroxene, set in a fine-grained groundmass that consists of new crystals of olivine and a glassy appearing matrix. This texture does not correspond to the description of the previously examined pieces of Netschaëvo, which consist of primitive chondrule-bearing angular clasts. Detailed petrographic observations and geochemical analyses suggest that the investigated samples of Netschaëvo consist of quenched impact melt. This implies that Netschaëvo is a breccia containing metamorphosed and impact-melt rock (IMR) clasts and that collisions played a major role in the formation of the IIE group.

A Computerized Weather Station for the Apple IIe.

ERIC Educational Resources Information Center

Lorson, Mark V.

Predicting weather conditions is a topic of interest for students who want to make plans for outside activities. This paper discusses the development of an inexpensive computer-interfaced classroom weather station using an Apple IIe computer that provides the viewer with up to the minute digital readings of inside and outside temperature,…

CD147 stimulates hepatoma cells escaping from immune surveillance of T cells by interaction with Cyclophilin A.

PubMed

Ren, Yi-Xin; Wang, Shu-Jing; Fan, Jian-Hui; Sun, Shi-Jie; Li, Xia; Padhiar, Arshad Ahmed; Zhang, Jia-Ning

2016-05-01

T cells play an important role in tumor immune surveillance. CD147 is a member of immunoglobulin superfamily present on the surface of many tumor cells and mediates malignant cell behaviors. Cyclophilin A (CypA) is an intracellular protein promoting inflammation when released from cells. CypA is a natural ligand for CD147. In this study, CD147 specific short hairpin RNAs (shRNA) were transfected into murine hepatocellular carcinoma Hepa1-6 cells to assess the effects of CD147 on hepatoma cells escaping from immune surveillance of T cells. We found extracellular CypA stimulated cell proliferation through CD147 by activating ERK1/2 signaling pathway. Downregulation of CD147 expression on Hepa1-6 cells significantly suppressed tumor progression in vivo, and decreased cell viability when co-cultured with T cells in vitro. Importantly, knockdown of CD147 on Hepa1-6 cells resulted in significantly increased T cells chemotaxis induced by CypA both in vivo and in vitro. These findings provide novel mechanisms how tumor cells escaping from immune surveillance of T cells. We provide a potential therapy for hepatocellular carcinoma by targeting CD147 or CD147-CypA interactions. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Pokemon silencing leads to Bim-mediated anoikis of human hepatoma cell QGY7703.

PubMed

Liu, Kun; Liu, Feng; Zhang, Nannan; Liu, Shiying; Jiang, Yuyang

2012-01-01

Pokemon is an important proto-oncogene that plays a critical role in cellular oncogenic transformation and tumorigenesis. Anoikis, which is regulated by Bim-mediated apoptosis, is critical to cancer cell invasion and metastasis. We investigated the role of Pokemon in anoikis, and our results show that Pokemon renders liver cells resistant to anoikis via suppression of Bim transcription. We knocked-down Pokemon in human hepatoma cells QGY7703 with small interfering RNAs (siRNA). Knockdown of Pokemon alone did not significantly affect the growth and survival of QGY7703 cells but notably enhanced their sensitivity to apoptotic stress due to the presence of chemical agents or cell detachment, thereby inducing anoikis, as evidenced by flow cytometry and caspase-3 activity assays. In contrast, ectopic expression of Pokemon in HL7702 cells led to resistance to anoikis. Dual-luciferase reporter and ChIP assays illustrated that Pokemon suppressed Bim transcription via direct binding to its promoter. Our results suggest that Pokemon prevents anoikis through the suppression of Bim expression, which facilitates tumor cell invasion and metastasis. This Pokemon-Bim pathway may be an effective target for therapeutic intervention for cancer.

Pokemon Silencing Leads to Bim-Mediated Anoikis of Human Hepatoma Cell QGY7703

PubMed Central

Liu, Kun; Liu, Feng; Zhang, Nannan; Liu, Shiying; Jiang, Yuyang

2012-01-01

Pokemon is an important proto-oncogene that plays a critical role in cellular oncogenic transformation and tumorigenesis. Anoikis, which is regulated by Bim-mediated apoptosis, is critical to cancer cell invasion and metastasis. We investigated the role of Pokemon in anoikis, and our results show that Pokemon renders liver cells resistant to anoikis via suppression of Bim transcription. We knocked-down Pokemon in human hepatoma cells QGY7703 with small interfering RNAs (siRNA). Knockdown of Pokemon alone did not significantly affect the growth and survival of QGY7703 cells but notably enhanced their sensitivity to apoptotic stress due to the presence of chemical agents or cell detachment, thereby inducing anoikis, as evidenced by flow cytometry and caspase-3 activity assays. In contrast, ectopic expression of Pokemon in HL7702 cells led to resistance to anoikis. Dual-luciferase reporter and ChIP assays illustrated that Pokemon suppressed Bim transcription via direct binding to its promoter. Our results suggest that Pokemon prevents anoikis through the suppression of Bim expression, which facilitates tumor cell invasion and metastasis. This Pokemon-Bim pathway may be an effective target for therapeutic intervention for cancer. PMID:22754333

Human Papillomavirus Type 18 E6 and E7 Genes Integrate into Human Hepatoma Derived Cell Line Hep G2

PubMed Central

Ma, Tianzhong; Su, Zhongjing; Chen, Ling; Liu, Shuyan; Zhu, Ningxia; Wen, Lifeng; Yuan, Yan; Lv, Leili; Chen, Xiancai; Huang, Jianmin; Chen, Haibin

2012-01-01

Background and Objectives Human papillomaviruses have been linked causally to some human cancers such as cervical carcinoma, but there is very little research addressing the effect of HPV infection on human liver cells. We chose the human hepatoma derived cell line Hep G2 to investigate whether HPV gene integration took place in liver cells as well. Methods We applied PCR to detect the possible integration of HPV genes in Hep G2 cells. We also investigated the expression of the integrated E6 and E7 genes by using RT-PCR and Western blotting. Then, we silenced E6 and E7 expression and checked the cell proliferation and apoptosis in Hep G2 cells. Furthermore, we analyzed the potential genes involved in cell cycle and apoptosis regulatory pathways. Finally, we used in situ hybridization to detect HPV 16/18 in hepatocellular carcinoma samples. Results Hep G2 cell line contains integrated HPV 18 DNA, leading to the expression of the E6 and E7 oncogenic proteins. Knockdown of the E7 and E6 genes expression reduced cell proliferation, caused the cell cycle arrest at the S phase, and increased apoptosis. The human cell cycle and apoptosis real-time PCR arrays analysis demonstrated E6 and E7-mediated regulation of some genes such as Cyclin H, UBA1, E2F4, p53, p107, FASLG, NOL3 and CASP14. HPV16/18 was found in only 9% (9/100) of patients with hepatocellular carcinoma. Conclusion Our investigations showed that HPV 18 E6 and E7 genes can be integrated into the Hep G2, and we observed a low prevalence of HPV 16/18 in hepatocellular carcinoma samples. However, the precise risk of HPV as causative agent of hepatocellular carcinoma needs further study. PMID:22655088

Zinc Mesoporphyrin Induces Rapid Proteasomal Degradation of Hepatitis C Nonstructural 5A Protein in Human Hepatoma Cells

PubMed Central

Hou, Weihong; Tian, Qing; Zheng, Jianyu; Bonkovsky, Herbert L.

2009-01-01

Background & Aims The nonstructural 5A (NS5A) protein of hepatitis C virus (HCV), plays a critical role in HCV replication and is an attractive target for the therapy of HCV infection. So far, little is known about the post-translational regulation of NS5A protein and its precise role in HCV RNA replication. Our objectives were to elucidate the down-regulation of NS5A protein and HCV RNA replication by zinc mesoporphyrin (ZnMP), and the mechanism by which this process occurs. Methods Human hepatoma cells expressing HCV proteins were used to investigate the post-translational regulation of ZnMP on NS5A protein by Western blots (WB) and immunoprecipitation (IP). Quantitative RT-PCR (qRT-PCR) was used to determine the effects of ZnMP on HCV RNA replication. Results ZnMP selectively and markedly down-regulated NS5A protein levels by increasing degradation of NS5A protein [half life fell from 18.7 h to 2.7 h]. The proteasome inhibitors, epoxomicin and MG132, significantly abrogated degradation of NS5A protein by ZnMP without affecting levels of NS5A in the absence of ZnMP. Analysis of immunoprecipitates with an anti-ubiquitin antibody revealed polyubiquitination of NS5A, suggesting that ZnMP induces ubiquitination of NS5A protein. In addition, 10 μM of ZnMP reduced HCV replication by ~63% in the Con1 replicon cells, ~70% in J6/JFH1 HCV transfected cells, and ~90% in J6/JFH1 HCV infected cells without affecting cell viability. Conclusions ZnMP produces a rapid and profound down-regulation of the NS5A protein by enhancing its polyubiquitination and proteasome-dependent catabolism. Zinc mesoporphyrin may hold promise as a novel agent to treat HCV infection. PMID:19909748

Antioxidative and apoptotic properties of polyphenolic extracts from edible part of artichoke (Cynara scolymus L.) on cultured rat hepatocytes and on human hepatoma cells.

PubMed

Miccadei, Stefania; Di Venere, Donato; Cardinali, Angela; Romano, Ferdinando; Durazzo, Alessandra; Foddai, Maria Stella; Fraioli, Rocco; Mobarhan, Sohrab; Maiani, Giuseppe

2008-01-01

Cultured rat hepatocytes and human hepatoma HepG2 cells were used to evaluate the hepatoprotective properties of polyphenolic extracts from the edible part of artichoke (AE). The hepatocytes were exposed to H2O2generated in situ by glucose oxidase and were treated with either AE, or pure chlorogenic acid (ChA) or with the well known antioxidant, N, N'-diphenyl-p-phenilenediamine (DPPD). Addition of glucose oxidase to the culture medium caused depletion of intracellular glutathione (GSH) content, accumulation of malondialdehyde (MDA) in the cultures, as a lipid peroxidation indicator, and cell death. These results demonstrated that AE protected cells from the oxidative stress caused by glucose oxidase, comparable to DPPD. Furthermore, AE, as well as ChA, prevented the loss of total GSH and the accumulation of MDA. Treatment of HepG2 cells for 24 h with AE reduced cell viability in a dose-dependent manner, however, ChA had no prominent effects on the cell death rate. Similarly, AE rather than ChA induced apoptosis, measured by flow cytometric analysis of annexin and by activation of caspase-3, in HepG2 cells. Our findings indicate that AE had a marked antioxidative potential that protects hepatocytes from an oxidative stress. Furthermore, AE reduced cell viability and had an apoptotic activity on a human liver cancer cell line.

Vinclozolin, a widely used fungizide, enhanced BaP-induced micronucleus formation in human derived hepatoma cells by increasing CYP1A1 expression.

PubMed

Wu, Xin-Jiang; Lu, Wen-qing; Roos, Peter H; Mersch-Sundermann, Volker

2005-10-15

Vinclozolin, a widely used fungicide, can be identified as a residue in numerous vegetable and fruit samples. To get insight in its genetic toxicity, we investigated the genotoxic effect of vinclozolin in the human derived hepatoma cell line HepG2 using the micronucleus (MN) assay. Additionally, to evaluate the co- or anti-mutagenic potency of vinclozolin, we treated HepG2 cells with different concentrations of vinclozolin for 24 h. Subsequently, the cells were exposed to benzo[a]pyrene (BaP) for 1h. Exposure of HepG2 cells to 50-400 microM vinclozolin alone did not cause any induction of micronuclei. However, a pronounced co-mutagenic effect was observed. MN frequencies caused by BaP increased by 30.6%, 52.8% and 65.3% after pretreatment of the cell cultures with 50, 100 and 200 microM vinclozolin, respectively. The highest concentration (400 microM) of vinclozolin tested caused cytotoxicity. Therefore, micronuclei were not considered for that concentration. To clarify the mechanism of cogenotoxicity, we assayed cytochrome P450 1A1 (CYP1A1), which plays a pivotal role in activation of BaP. Cells exposed to vinclozolin led to significant increase of CYP1A1 expression in Western blot. The result suggested that induction of CYP1A1 by vinclozolin account for its enhancing effect on genotoxicity caused by BaP.

Tumor Regression and Delayed Onset Toxicity Following B7-H4 CAR T Cell Therapy

PubMed Central

Smith, Jenessa B; Lanitis, Evripidis; Dangaj, Denarda; Buza, Elizabeth; Poussin, Mathilde; Stashwick, Caitlin; Scholler, Nathalie; Powell, Daniel J

2016-01-01

B7-H4 protein is frequently overexpressed in ovarian cancer. Here, we engineered T cells with novel B7-H4-specific chimeric antigen receptors (CARs) that recognized both human and murine B7-H4 to test the hypothesis that B7-H4 CAR T cell therapy can be applied safely in preclinical models. B7-H4 CAR T cells specifically secreted IFN-γ and lysed B7-H4(+) targets. In vivo, B7-H4 CAR T cells displayed antitumor reactivity against B7-H4(+) human ovarian tumor xenografts. Unexpectedly, B7-H4 CAR T cell treatment reproducibly showed delayed, lethal toxicity 6–8 weeks after therapy. Comprehensive assessment of murine B7-H4 protein distribution uncovered expression in ductal and mucosal epithelial cells in normal tissues. Postmortem analysis revealed the presence of widespread histologic lesions that correlated with B7-H4(+) expression, and were inconsistent with graft versus host disease. Lastly, expression patterns of B7-H4 protein in normal human tissue were comparable to distribution in mice, advancing our understanding of B7-H4. We conclude that B7-H4 CAR therapy mediates control of cancer outgrowth. However, long-term engraftment of B7-H4 CAR T cells mediates lethal, off-tumor toxicity that is likely due to wide expression of B7-H4 in healthy mouse organs. This model system provides a unique opportunity for preclinical evaluation of safety approaches that limit CAR-mediated toxicity after tumor destruction in vivo. PMID:27439899

B7-H4 as a protective shield for pancreatic islet beta cells.

PubMed

Sun, Annika C; Ou, Dawei; Luciani, Dan S; Warnock, Garth L

2014-12-15

Auto- and alloreactive T cells are major culprits that damage β-cells in type 1 diabetes (T1D) and islet transplantation. Current immunosuppressive drugs can alleviate immune-mediated attacks on islets. T cell co-stimulation blockade has shown great promise in autoimmunity and transplantation as it solely targets activated T cells, and therefore avoids toxicity of current immunosuppressive drugs. An attractive approach is offered by the newly-identified negative T cell co-signaling molecule B7-H4 which is expressed in normal human islets, and its expression co-localizes with insulin. A concomitant decrease in B7-H4/insulin co-localization is observed in human type 1 diabetic islets. B7-H4 may play protective roles in the pancreatic islets, preserving their function and survival. In this review we outline the protective effect of B7-H4 in the contexts of T1D, islet cell transplantation, and potentially type 2 diabetes. Current evidence offers encouraging data regarding the role of B7-H4 in reversal of autoimmune diabetes and donor-specific islet allograft tolerance. Additionally, unique expression of B7-H4 may serve as a potential biomarker for the development of T1D. Future studies should continue to focus on the islet-specific effects of B7-H4 with emphasis on mechanistic pathways in order to promote B7-H4 as a potential therapy and cure for T1D.

Increased PRPP synthetase activity in cultured rat hepatoma cells containing mutations in the hypoxanthine-guanine phosphoribosyltransferase gene.

PubMed

Graf, L H; McRoberts, J A; Harrison, T M; Martin, D W

1976-07-01

Nine independently derived clones of mutagenized rat hepatoma cells selected for resistance to 6-mercaptopurine (6-MP) or 6-thioguanine (6-ThioG) have been isolated. Each has severely reduced catalytic activity of hypoxanthine-guanine phosphoribosyltransferase (HPRT) and seven of them possess significantly increased activities of phosphoribosylpyrophosphate (PRPP) synthetase. The degrees of elevations of PRPP synthetase activities do not correlate with the degrees of deficiencies of HPRT activities. The cells from one of these clones, 1020/12, posses 40% of the normal HPRT catalytic activity and overproduce purines. We have extensively examined the cells from this clone. Immunotration studies of 1020/12 cells indicate that there is a mutation in the structural gene for HPRT. Although they possess increased specific catalytic activities of the enzyme. PRPP synthetase, the catalytic parameters, heat stability, and isoelectric pH of PRPP synthetase from 1020/12 cells are indistinguishable from those of the enzyme from wild-type cells. The cause of purine overproduction by 1020/12 cells appears to be the elevated PRPP synthetase activity, rather than a PRPP "sparing" effect stemming from reduced HPRT activity. Support for this idea is provided by the observation that the complete loss of HPRT activity in a clone derived from 1020/12 cells does not further enhance the levels of PRPP synthetase or purine overproduction. We propose that the elevated levels of PRPP synthetase activity in these HPRT deficient cells result from a mutational event in the structural gene for HPRT, and that this causes the disruption of a previously undescribed regulatory function of this gene on the expression of the PRPP synthetase gene.

Apple IIe Computers and Appleworks Training Mini Course Materials.

ERIC Educational Resources Information Center

Schlenker, Richard M.

The instructional materials included in this document are designed to introduce students to the Apple IIe computer and to the word processing and database portions of the AppleWorks program. The materials are intended for small groups of students, each of whom has use of a computer during class and for short periods between classes. The course…

Antitumor activity of Type I and Type III interferons in BNL hepatoma model

PubMed Central

Abushahba, Walid; Balan, Murugabaskar; Castaneda, Ismael; Yuan, Yao; Reuhl, Kenneth; Raveche, Elizabeth; de la Torre, Andrew

2015-01-01

Hepatocellular carcinoma (HCC) occurs most commonly secondary to cirrhosis due to chronic hepatitis C or B virus (HCV/HBV) infections. Type I interferon (IFN-α) treatment of chronic HCV/HBV infections reduces the incidence of HCC in cirrhotic patients. However, IFN-α toxicity limits its tolerability and efficacy highlighting a need for better therapeutic treatments. A recently discovered type III IFN (IFN-λ) has been shown to possess antiviral properties against HCV and HBV in vitro. In phase I clinical trials, IFN-λ treatment did not cause significant adverse reactions. Using a gene therapy approach, we compared the antitumor properties of IFN-α and IFN-λ in a transplantable hepatoma model of HCC. BALB/c mice were inoculated with syngeneic BNL hepatoma cells, or BNL cells expressing IFN-λ (BNL.IFN-λ cells) or IFN-α (BNL.IFN-α cells). Despite the lack of antiproliferative activity of IFNs on BNL cells, both BNL.IFN-λ and BNL.IFN-α cells displayed retarded growth kinetics in vivo. Depletion of NK cells from splenocytes inhibited splenocyte-mediated cytotoxicity, demonstrating that NK cells play a role in IFN-induced antitumor responses. However, isolated NK cells did not respond directly to IFN-λ. There was also a marked NK cell infiltration in IFN-λ producing tumors. In addition, IFN-λ and, to a lesser extent, IFN-α enhanced immunocytotoxicity of splenocytes primed with irradiated BNL cells. Splenocyte cytotoxicity against BNL cells was dependent on IL-12 and IFN-λ, and mediated by dendritic cells. In contrast to NK cells, isolated from spleen CD1 1c+ and mPDCA+ dendritic cells responded directly to IFN-λ. The antitumor activities of IFN-λ against hepatoma, in combination with HCV and HBV antiviral activities warrant further investigation into the clinical use of IFN-λ to prevent HCC in HCV/HBV-infected cirrhotic patients, as well as to treat liver cancer. PMID:20217081

Antitumor activity of type I and type III interferons in BNL hepatoma model.

PubMed

Abushahba, Walid; Balan, Murugabaskar; Castaneda, Ismael; Yuan, Yao; Reuhl, Kenneth; Raveche, Elizabeth; de la Torre, Andrew; Lasfar, Ahmed; Kotenko, Sergei V

2010-07-01

Hepatocellular carcinoma (HCC) occurs most commonly secondary to cirrhosis due to chronic hepatitis C or B virus (HCV/HBV) infections. Type I interferon (IFN-alpha) treatment of chronic HCV/HBV infections reduces the incidence of HCC in cirrhotic patients. However, IFN-alpha toxicity limits its tolerability and efficacy highlighting a need for better therapeutic treatments. A recently discovered type III IFN (IFN-lambda) has been shown to possess antiviral properties against HCV and HBV in vitro. In phase I clinical trials, IFN-lambda treatment did not cause significant adverse reactions. Using a gene therapy approach, we compared the antitumor properties of IFN-alpha and IFN-lambda in a transplantable hepatoma model of HCC. BALB/c mice were inoculated with syngeneic BNL hepatoma cells, or BNL cells expressing IFN-lambda (BNL.IFN-lambda cells) or IFN-alpha (BNL.IFN-alpha cells). Despite the lack of antiproliferative activity of IFNs on BNL cells, both BNL.IFN-lambda and BNL.IFN-alpha cells displayed retarded growth kinetics in vivo. Depletion of NK cells from splenocytes inhibited splenocyte-mediated cytotoxicity, demonstrating that NK cells play a role in IFN-induced antitumor responses. However, isolated NK cells did not respond directly to IFN-lambda. There was also a marked NK cell infiltration in IFN-lambda producing tumors. In addition, IFN-lambda and, to a lesser extent, IFN-alpha enhanced immunocytotoxicity of splenocytes primed with irradiated BNL cells. Splenocyte cytotoxicity against BNL cells was dependent on IL-12 and IFN-gamma, and mediated by dendritic cells. In contrast to NK cells, isolated from spleen CD11c+ and mPDCA+ dendritic cells responded directly to IFN-lambda. The antitumor activities of IFN-lambda against hepatoma, in combination with HCV and HBV antiviral activities warrant further investigation into the clinical use of IFN-lambda to prevent HCC in HCV/HBV-infected cirrhotic patients, as well as to treat liver cancer.

Expression of human inducible nitric oxide synthase in a tetrahydrobiopterin (H4B)-deficient cell line: H4B promotes assembly of enzyme subunits into an active dimer.

PubMed Central

Tzeng, E; Billiar, T R; Robbins, P D; Loftus, M; Stuehr, D J

1995-01-01

Murine inducible nitric oxide (NO) synthase (iNOS) is catalytically active only in dimeric form. Assembly of its purified subunits into a dimer requires H4B. To understand the structure-activity relationships of human iNOS, we constitutively expressed recombinant human iNOS in NIH 3T3 cells by using a retroviral vector. These cells are deficient in de novo H4B biosynthesis and the role of H4B in the expression and assembly of active iNOS in an intact cell system could be studied. In the absence of added H4B, NO synthesis by the cells was minimal, whereas cells grown with supplemental H4B or the H4B precursor sepiapterin generated NO (74.1 and 63.3 nmol of nitrite per 10(6) cells per 24 h, respectively). NO synthesis correlated with an increase in intracellular H4B but no increase in iNOS protein. Instead, an increased percentage of dimeric iNOS was observed, rising from 20% in cytosols from unsupplemented cells to 66% in H4B-supplemented cell cytosols. In all cases, only dimeric iNOS displayed catalytic activity. Cytosols prepared from H4B-deficient cells exhibited little iNOS activity but acquired activity during a 60- to 120-min incubation with H4B, reaching final activities of 60-72 pmol of citrulline per mg of protein per min. Reconstitution of cytosolic NO synthesis activity was associated with conversion of monomers into dimeric iNOS during the incubation. Thus, human iNOS subunits dimerize to form an active enzyme, and H4B plays a critical role in promoting dimerization in intact cells. This reveals a post-translational mechanism by which intracellular H4B can regulate iNOS expression. Images Fig. 1 Fig. 3 Fig. 4 Fig. 5 PMID:8524846

Intrinsic anticarcinogenic effects of Piper sarmentosum ethanolic extract on a human hepatoma cell line

PubMed Central

Zainal Ariffin, Shahrul Hisham; Wan Omar, Wan Haifa Haryani; Zainal Ariffin, Zaidah; Safian, Muhd Fauzi; Senafi, Sahidan; Megat Abdul Wahab, Rohaya

2009-01-01

Background Piper sarmentosum, locally known as kaduk is belonging to the family of Piperaceae. It is our interest to evaluate their effect on human hepatoma cell line (HepG2) for the potential of anticarcinogenic activity. Results The anticarcinogenic activity of an ethanolic extract from Piper sarmentosum in HepG2 and non-malignant Chang's liver cell lines has been previously determined using (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) (MTT) assays, where the IC50 value was used as a parameter for cytotoxicity. The ethanolic extract that showed anticarcinogenic properties in HepG2 cells had an IC50 of 12.5 μg mL-1, while IC50 values in the non-malignant Chang's liver cell line were greater than 30 μg mL-1. Apoptotic morphological changes in HepG2 cells were observed using an inverted microscope and showed chromatin condensation, cell shrinkage and apoptotic bodies following May-Grunwald-Giemsa's staining. The percentage of apoptotic cells in the overall population (apoptotic index) showed a continuously significant increase (p < 0.05) in 12.5 μg mL-1 ethanolic extract-treated cells at 24, 48 and 72 hours compared to controls (untreated cells). Following acridine orange and ethidium bromide staining, treatment with 10, 12 and 14 μg mL-1 of ethanolic extracts caused typical apoptotic morphological changes in HepG2 cells. Molecular analysis of DNA fragmentation was used to examine intrinsic apoptosis induced by the ethanolic extracts. These results showed a typical intrinsic apoptotic characterisation, which included fragmentation of nuclear DNA in ethanolic extract-treated HepG2 cells. However, the non-malignant Chang's liver cell line produced no DNA fragmentation. In addition, the DNA genome was similarly intact for both the untreated non-malignant Chang's liver and HepG2 cell lines. Conclusion Therefore, our results suggest that the ethanolic extract from P. sarmentosum induced anticarcinogenic activity through an intrinsic apoptosis

Evaluation of the anticancer potential of six herbs against a hepatoma cell line

PubMed Central

2012-01-01

Background Six herbs in the Plant Genetics Conservation Project that have been used as complementary medicines were chosen on the basis of their medicinal value, namely Terminalia mucronata, Diospyros winitii, Bridelia insulana, Artabotrys harmandii, Terminallia triptera, and Croton oblongifolius. This study aims to evaluate the potential anticancer activity of 50% ethanol-water extracts of these six herbs. Methods Fifty percent ethanol-water crude extracts of the six herbs were prepared. The cytotoxicity of the herbal extracts relative to that of melphalan was evaluated using a hepatoma cell line (HepG2), and examined by neutral red assays and apoptosis induction by gel electrophoresis and flow cytometry after 24 h. Results A significant difference was found between the cytotoxicity of the 50% ethanol-water crude extracts and melphalan (P = 0.000). The 50% ethanol-water crude extracts of all six herbs exhibited cytotoxicity against HepG2 cells, with IC50 values ranging from 100 to 500 μg/mL. The extract of T. triptera showed the highest cytotoxicity with an IC50 of 148.7 ± 12.3 μg/mL, while melphalan had an IC50 of 39.79 ± 7.62 μg/mL. The 50% ethanol-water crude extracts of D. winitii and T. triptera, but not A. harmandii, produced a DNA ladder. The 50% ethanol-water crude extracts of D. winitii, T. triptera, and A. harmandii induced apoptosis detected by flow cytometry. Conclusion The 50% ethanol-water crude extracts of D. winitii, T. triptera, and A. harmandii showed anticancer activity in vitro. PMID:22682026

Evaluating the potential of (188)Re-ECD/lipiodol as a therapeutic radiopharmaceutical by intratumoral injection for hepatoma treatment.

PubMed

Luo, Tsai-Yueh; Shih, Ying-Hsia; Chen, Chiung-Yu; Tang, I-Chung; Wu, Yu-Long; Kung, Hong-Chang; Lin, Wuu-Jyh; Lin, Xi-Zhang

2009-10-01

Intratumoral injection of a radiopharmaceutical is a potential modality to treat liver tumors. Rhenium-188 ((188)Re) was used to chelate with ethyl cysteinate dimer (ECD) in lipiodol solution to form (188)Re-ECD/lipiodol, which was then evaluated for its therapeutic potential in a rodent hepatoma model. Male Sprague-Dawley rats were implanted with N1-S1 hepatoma cells orthotopically and randomly divided into two groups. Group 1 (n = 29) and group 2 (n = 10) received (188)Re-ECD/lipiodol (30.4 +/- 21.8 MBq/0.1 mL) and 0.1 mL of normal saline by intratumoral injection, respectively. Three rats in group 1 were imaged by micro-single-photon emission computed tomography/computed tomography scan to evaluate the biodistribution pattern. All rats were monitored for change of tumor size and survival rate after 2 months. The in vitro stability test showed that (188)Re-ECD was well-retained in the lipiodol phase for 48 hours. The biodistribution image revealed that radioactivity was retained well in hepatomas 24 hours postinjection. Long-term studies demonstrated that rats treated with (188)Re-ECD/Lipiodol had smaller tumor volumes and a better survival rate, compared to the control group. At the end of observation, the survival rates in groups 1 and 2 were 62% and 20%, respectively (p < 0.05). (188)Re-ECD/lipiodol via direct intratumoral injection shows potential for treating hepatoma and warrants further clinical trials.

The potential role of GLUT4 transporters and insulin receptors in the hypoglycaemic activity of Ficus lutea acetone leaf extract.

PubMed

Olaokun, Oyinlola O; McGaw, Lyndy J; Awouafack, Maurice D; Eloff, Jacobus N; Naidoo, Vinny

2014-07-28

Some Ficus species have been used in traditional African medicine in the treatment of diabetes. The antidiabetic potential of certain species has been confirmed in vivo but the mechanism of activity remains uncertain. The aim was to investigate the hypoglycaemic potential of ten Ficus species focussing on glucose uptake, insulin secretion and the possible mechanism of hypoglycaemic activity. The dried and ground leaves of ten Ficus species were extracted with acetone. The dried acetone extract was reconstituted with DMSO to a concentration of 100 mg/ml which was then serially diluted and used to assay for glucose uptake in muscle, fat and liver cells, and insulin secretion in pancreatic cells. Only the F. lutea extract was able to modulate glucose metabolism. In comparison to insulin in the primary muscle cells, the glucose uptake ability of the extract was 33% as effective. In the hepatoma cell line, the extract was as effective as metformin in decreasing extracellular glucose concentration by approximately 20%. In the pancreatic insulin secretory assay, the extract was 4 times greater in its secretory activity than commercial glibenclamide. With F. lutea extract significantly increasing glucose uptake in the primary muscle cells, primary fat cells, C2C12 muscle and H-4-II-E liver cells, the extract may act by increasing the activity of cell surface glucose transporters. When the 3T3-L1 pre-adipocytes were compared to the primary muscle, primary fat and C2C12 cells, the differences in the former's ability to transport glucose into the cell may be due to the absence of the GLUT4 transporter, which on activation via the insulin receptor decreases extracellular glucose concentrations. Because the pre-adipocytes failed to show any active increase in glucose uptake, the present effect has to be linked to the absence of the GLUT4 transporter. Only F. lutea possessed substantial in vitro activity related to glucose metabolism. Based on the effect produced in the various

Chemopreventive Activities of Sulforaphane and Its Metabolites in Human Hepatoma HepG2 Cells.

PubMed

Liu, Peng; Wang, Wei; Zhou, Zhigang; Smith, Andrew J O; Bowater, Richard P; Wormstone, Ian Michael; Chen, Yuqiong; Bao, Yongping

2018-05-09

Sulforaphane (SFN) exhibits chemopreventive effects through various mechanisms. However, few studies have focused on the bioactivities of its metabolites. Here, three metabolites derived from SFN were studied, known as sulforaphane glutathione, sulforaphane cysteine and sulforaphane- N -acetylcysteine. Their effects on cell viability, DNA damage, tumorigenicity, cell migration and adhesion were measured in human hepatoma HepG2 cells, and their anti-angiogenetic effects were determined in a 3D co-culture model of human umbilical vein endothelial cells (HUVECs) and pericytes. Results indicated that these metabolites at high doses decreased cancer cell viability, induced DNA damage and inhibited motility, and impaired endothelial cell migration and tube formation. Additionally, pre-treatment with low doses of SFN metabolites protected against H₂O₂ challenge. The activation of the nuclear factor E2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway and the induction of intracellular glutathione (GSH) played an important role in the cytoprotective effects of SFN metabolites. In conclusion, SFN metabolites exhibited similar cytotoxic and cytoprotective effects to SFN, which proves the necessity to study the mechanisms of action of not only SFN but also of its metabolites. Based on the different tissue distribution profiles of these metabolites, the most relevant chemical forms can be selected for targeted chemoprevention.

Hydroquinone stimulates cell invasion through activator protein-1-dependent induction of MMP-9 in HepG2 human hepatoma cells.

PubMed

Yu, Mi-Hee; Lee, Syng-Ook

2016-03-01

Hydroquinone (HQ) is a well-known environmental carcinogen and exposure of humans to HQ can also occur through plant foods, cosmetics, and tobacco products. Although liver is a major organ metabolizing HQ and susceptible to its toxicity, role of HQ in metastatic progression of human hepatocellular carcinoma (HCC) remains unclear. In this study, we examined the effect of HQ on the invasion of HCC cells and its underlying molecular mechanisms. HQ strongly induced matrix metalloproteinase-9 (MMP-9) expression and secretion in HepG2 human hepatoma cells, which were well correlated with increased cell invasion. Mechanistic studies further demonstrated that HQ induced transcriptional activity of MMP-9 gene by activating activator protein-1 (AP-1), the well-known key element mediating MMP-9 gene expression, via MAP kinase (MAPK) signaling pathways. These results suggest that HQ may promote metastatic progression of HCC, although data on in vivo hydroquinone exposure and risk for HCC are contradictory. Copyright © 2016 Elsevier Ltd. All rights reserved.

H3K4me3 breadth is linked to cell identity and transcriptional consistency.

PubMed

Benayoun, Bérénice A; Pollina, Elizabeth A; Ucar, Duygu; Mahmoudi, Salah; Karra, Kalpana; Wong, Edith D; Devarajan, Keerthana; Daugherty, Aaron C; Kundaje, Anshul B; Mancini, Elena; Hitz, Benjamin C; Gupta, Rakhi; Rando, Thomas A; Baker, Julie C; Snyder, Michael P; Cherry, J Michael; Brunet, Anne

2014-07-31

Trimethylation of histone H3 at lysine 4 (H3K4me3) is a chromatin modification known to mark the transcription start sites of active genes. Here, we show that H3K4me3 domains that spread more broadly over genes in a given cell type preferentially mark genes that are essential for the identity and function of that cell type. Using the broadest H3K4me3 domains as a discovery tool in neural progenitor cells, we identify novel regulators of these cells. Machine learning models reveal that the broadest H3K4me3 domains represent a distinct entity, characterized by increased marks of elongation. The broadest H3K4me3 domains also have more paused polymerase at their promoters, suggesting a unique transcriptional output. Indeed, genes marked by the broadest H3K4me3 domains exhibit enhanced transcriptional consistency and [corrected] increased transcriptional levels, and perturbation of H3K4me3 breadth leads to changes in transcriptional consistency. Thus, H3K4me3 breadth contains information that could ensure transcriptional precision at key cell identity/function genes. Copyright © 2014 Elsevier Inc. All rights reserved.

Toxicity assessment of metoprolol and its photodegradation mixtures obtained by using different type of TiO2 catalysts in the mammalian cell lines.

PubMed

Četojević-Simin, Dragana D; Armaković, Sanja J; Šojić, Daniela V; Abramović, Biljana F

2013-10-01

Toxicity of metoprolol (MET) alone and in mixtures with its photocatalytic degradation intermediates obtained by using TiO2 Wackherr and Degussa P25 under UV irradiation in the presence of O2 was evaluated in vitro in a panel of three histologically different cell lines: rat hepatoma (H-4-II-E), human colon adenocarcinoma (HT-29) and human fetal lung (MRC-5). Both catalysts promoted a time-dependent increase in the toxicity of the photodegradation products, and those obtained using Degussa P25 photocatalyst were more toxic. The most pronounced and selective toxic action of MET and products of its photodegradation was observed in the hepatic cell line. The higher toxicity of the mixtures obtained using Degussa P25 catalyst could be explained by a different mechanism of MET degradation, i.e. by the presence or higher concentrations of some intermediates. Although the concentrations of intermediates obtained using TiO2 Wackherr catalyst were higher, they did not affect significantly the growth of the examined cell lines, indicating their lower toxicity. This suggests that a treatment aiming at complete mineralization should be performed bearing in mind that the type of catalyst, the concentration of target molecule, and the duration of the process are significant factors that determine the nature and toxicity of the resulting mixtures. Although the EC50 values of MET obtained in mammalian cell lines were higher compared to the bioassays for lower trophic levels, the time-dependent promotion of toxicity of degradation mixtures should be attributed to the higher sensitivity of mammalian cell bioassays. © 2013 Elsevier B.V. All rights reserved.

Acetyl-CoA carboxylase in Reuber hepatoma cells: variation in enzyme activity, insulin regulation, and cellular lipid content.

PubMed

Bianchi, A; Evans, J L; Nordlund, A C; Watts, T D; Witters, L A

1992-01-01

Reuber hepatoma cells are useful cultured lines for the study of insulin action, lipid and lipoprotein metabolism, and the regulation of acetyl-CoA carboxylase (ACC), the rate-limiting enzyme of fatty acid biosynthesis. During investigations in different clonal lines of these cells, we have uncovered marked intercellular variability in the activity, enzyme content, and insulin regulation of ACC paralleled by differences in cellular neutral lipid (triglyceride) content. Two contrasting clonal lines, Fao and H356A-1, have been studied in detail. Several features distinguish these two lines, including differences in ACC activity and enzyme kinetics, the content of the two major hepatic ACC isozymes (Mr 280,000 and 265,000 Da) and their heteroisozymic complex, the extent of ACC phosphorylation, and the ability of ACC to be activated on stimulation by insulin and insulinomimetic agonists. As studied by Nile Red staining and fluorescence-activated cell sorting, these two lines also display marked differences in neutral lipid content, which correlates with both basal levels of ACC activity and inhibition of ACC by the fatty acid analog, 5-(tetradecyloxy)-2-furoic acid (TOFA). These results emphasize the importance of characterization of any particular clonal line of Reuber cells for studies of enzyme regulation, substrate metabolism, and hormone action. With respect to ACC, studies in contrasting clonal lines of Reuber cells could provide valuable clues to understanding both the complex mechanisms of intracellular ACC regulation in the absence and presence of hormones and its regulatory role(s) in overall hepatic lipid metabolism.

EML4-ALK induces epithelial–mesenchymal transition consistent with cancer stem cell properties in H1299 non-small cell lung cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guo, Fuchun; Liu, Xiaoke, E-mail: liuxk57@163.com; Qing, Qin, E-mail: qinqingscu@126.com

2015-04-10

The echinoderm microtubule-associated protein-like 4(EML4) – anaplastic lymphoma kinase (ALK) fusion gene has been identified as a driver mutation in non-small-cell lung cancer (NSCLC). However, the role of EML4-ALK in malignant transformation is not entirely clear. Here, for the first time, we showed that H1299 NSCLC cells stably expressing EML4-ALK acquire EMT phenotype, associated with enhanced invasive migration and increased expression of EMT-inducing transcription factors. H1299-EML4-ALK cells also displayed cancer stem cell-like properties with a concomitant up-regulation of CD133 and enhanced ability of mammospheres formation. Moreover, we found that inhibition of ERK1/2 reversed EMT induced by EML4-ALK in H1299 cells.more » Taken together, these results suggested that EML4-ALK induced ERK activation is mechanistically associated with EMT phenotype. Thus, inhibition of ERK signaling pathway could be a potential strategy in treatment of NSCLC patients with EML4-ALK translocation. - Highlights: • EML4-ALK induced epithelial–mesenchymal transition in H1299 cells. • Expression of EML4-ALK promotes invasion and migration in vitro. • EML4-ALK enhanced sphere formation and stem cell-like properties in H1299 cells. • Blockage of ERK1/2 reverse Epithelial–Mesenchymal transition induced by EML4-ALK.« less

Complete replication of hepatitis B virus and hepatitis C virus in a newly developed hepatoma cell line.

PubMed

Yang, Darong; Zuo, Chaohui; Wang, Xiaohong; Meng, Xianghe; Xue, Binbin; Liu, Nianli; Yu, Rong; Qin, Yuwen; Gao, Yimin; Wang, Qiuping; Hu, Jun; Wang, Ling; Zhou, Zebin; Liu, Bing; Tan, Deming; Guan, Yang; Zhu, Haizhen

2014-04-01

The absence of a robust cell culture system for hepatitis B virus (HBV) and hepatitis C virus (HCV) infection has limited the analysis of the virus lifecycle and drug discovery. We have established a hepatoma cell line, HLCZ01, the first cell line, to the authors' knowledge, supporting the entire lifecycle of both HBV and HCV. HBV surface antigen (HBsAg)-positive particles can be observed in the supernatant and the lumen of the endoplasmic reticulum of the cells via electron microscopy. Interestingly, HBV and HCV clinical isolates propagate in HLCZ01 cells. Both viruses replicate in the cells without evidence of overt interference. HBV and HCV entry are blocked by antibodies against HBsAg and human CD81, respectively, and the replication of HBV and HCV is inhibited by antivirals. HLCZ01 cells mount an innate immune response to virus infection. The cell line provides a powerful tool for exploring the mechanisms of virus entry and replication and the interaction between host and virus, facilitating the development of novel antiviral agents and vaccines.

Solvent-Free Addition of Indole to Aldehydes: Unexpected Synthesis of Novel 1-[1-(1H-Indol-3-yl) Alkyl]-1H-Indoles and Preliminary Evaluation of Their Cytotoxicity in Hepatocarcinoma Cells.

PubMed

Tocco, Graziella; Zedda, Gloria; Casu, Mariano; Simbula, Gabriella; Begala, Michela

2017-10-17

New 1-[1-(1 H -indol-3-yl) alkyl]-1 H -indoles, surprisingly, have been obtained from the addition of indole to a variety of aldehydes under neat conditions. CaO, present in excess, was fundamental for carrying out the reaction with paraformaldehyde. Under the same reaction conditions, aromatic and heteroaromatic aldehydes afforded only classical bis (indolyl) aryl indoles. In this paper, the role of CaO, together with the regiochemistry and the mechanism of the reaction, are discussed in detail. The effect of some selected 3,3'- and 1,3'-diindolyl methane derivatives on cell proliferation of the hepatoma cell line FaO was also evaluated.

Saponins isolated from Asparagus induce apoptosis in human hepatoma cell line HepG2 through a mitochondrial-mediated pathway

PubMed Central

Ji, Y.; Ji, C.; Yue, L.; Xu, H.

2012-01-01

Objective Many scientific studies have shown that Asparagus officinalis has an antitumour effect and enhances human immunity, but the active components and the antitumour mechanisms are unclear. We investigated the effects of saponins isolated from Asparagus on proliferation and apoptosis in the human hepatoma cell line HepG2. Methods HepG2 cells were treated with varying concentrations of Asparagus saponins at various times. Using mtt and flow cytometry assays, we evaluated the effects of Asparagus saponins on the growth and apoptosis of HepG2 cells. Transmission electron microscopy was used to observe the morphology of cell apoptosis. Confocal laser scanning microscopy was used to analyze intracellular calcium ion concentration, mitochondrial permeability transition pore (mptp), and mitochondrial membrane potential (mmp). Spectrophotometry was applied to quantify the activity of caspase-9 and caspase-3. Flow cytometry was used to investigate the levels of reactive oxygen species (ros) and pH, and the expressions of Bcl2, Bax, CytC, and caspase-3, in HepG2 cells. Results Asparagus saponins inhibited the growth of HepG2 cells in a dose-dependent manner. The median inhibitory concentration (IC50) was 101.15 mg/L at 72 hours. The apoptosis morphology at 72 hours of treatment was obvious, showing cell protuberance, concentrated cytoplasm, and apoptotic bodies. The apoptotic rates at 72 hours were 30.9%, 51.7%, and 62.1% (for saponin concentrations of 50 mg/L, 100 mg/L, 200 mg/L). Treatment with Asparagus saponins for 24 hours increased the intracellular level of ros and Ca2+, lowered the pH, activated intracellular mptp, and decreased mmp in a dose-dependent manner. Treatment also increased the activity of caspase-9 and caspase-3, downregulated the expression of Bcl2, upregulated the expression of Bax, and induced release of CytC and activation of caspase-3. Conclusions Asparagus saponins induce apoptosis in HepG2 cells through a mitochondrial-mediated and caspase

Phosphorus NMR of isolated perfused morris hepatomas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Graham, R.A.; Meyer, R.A.; Brown, T.R.

1986-03-05

The authors are developing techniques for the study of perfused solid tumors by NMR. Tissue-isolated solid hepatomas were grown to 1-2 cm diameter as described previously. The arterial supply was isolated and the tumors perfused (0.5 - 1.0 ml/min) in vitro at 25 C with a 15% suspension of red blood cells in Krebs-Henseliet solution. /sup 31/P-NMR spectra were acquired at 162 MHz in a specially-designed NMR probe using a solenoidal coil. Intracellular pH (monitored from the chemical shift of inorganic phosphate) and ATP levels were stable for up to 6 hrs during perfusion. During 30 min of global ischemia,more » ATP decreased by 75% and pH fell from 7.0 to 6.7. These changes were reversed by 1 hr reperfusion. In addition to ATP and phosphate, the spectra included a large resonance due to phosphomonoesters, as well as peaks consistent with glycerylphosphocholine, glyceryl-phosphoethanolamine, phosphocreatine, NAD, and UDPG. However, the most novel feature of the spectra was the presence of an unidentified peak in the phosphonate region (+ 16.9 ppm). The peak was not present in spectra of muscle, liver, brain, kidney, or fat tissues excised from the same animals. They are presently attempting to identify the compound that gives rise to this peak and to establish its metabolic origin.« less

Genotoxic effect of 6-gingerol on human hepatoma G2 cells.

PubMed

Yang, Guang; Zhong, Laifu; Jiang, Liping; Geng, Chengyan; Cao, Jun; Sun, Xiance; Ma, Yufang

2010-04-15

6-gingerol, a major component of ginger, has antioxidant, anti-apoptotic, and anti-inflammatory activities. However, some dietary phytochemicals possess pro-oxidant effects as well, and the risk of adverse effects is increased by raising the use of doses. The aim of this study was to assess the genotoxic effects of 6-gingerol and to clarify the mechanisms, using human hepatoma G2 (HepG2) cells. Exposure of the cells to 6-gingerol caused significant increase of DNA migration in comet assay, increase of micronuclei frequencies at high concentrations at 20-80 and 20-40 microM, respectively. These results indicate that 6-gingerol caused DNA strand breaks and chromosome damage. To further elucidate the underlying mechanisms, we tested lysosomal membrane stability, mitochondrial membrane potential, the intracellular generation of reactive oxygen species (ROS) and reduced glutathione (GSH). In addition, the level of oxidative DNA damage was evaluated by immunocytochemical analysis on 8-hydroxydeoxyguanosine (8-OHdG). Results showed that lysosomal membrane stability was reduced after treatment by 6-gingerol (20-80 microM) for 40 min, mitochondrial membrane potential decreased after treatment for 50 min, GSH and ROS levels were significantly increased after treatment for 60 min. These suggest 6-gingerol induces genotoxicity probably by oxidative stress; lysosomal and mitochondrial damage were observed in 6-gingerol-induced toxicity. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Cytotoxic and genotoxic potential of geraniol in peripheral blood mononuclear cells and human hepatoma cell line (HepG2).

PubMed

Queiroz, T B; Santos, G F; Ventura, S C; Hiruma-Lima, C A; Gaivão, I O M; Maistro, E L

2017-09-27

Geraniol is an acyclic monoterpene alcohol present in the essential oil of many aromatic plants and is one of the most frequently used molecules by the flavor and fragrance industries. The literature also reports its therapeutic potential, highlighting itself especially as a likely molecule for the development of drugs against cancer. In view of these considerations, this study was designed to evaluate the cytotoxic and genotoxic potential of geraniol, in an in vitro protocol, using two types of human cells: one without the ability to metabolize (peripheral blood mononuclear cells - PBMC), and the other with this capability (human hepatoma cell line - HepG2) through the comet assay and the micronucleus test. Four concentrations (10, 25, 50, and 100 µg/mL) were selected for the genotoxic assessment for PBMC and three (1.25, 2.5, and 5 µg/mL) for HepG2 cells based on cytotoxicity tests (MTT assay). Results showed that geraniol did not present genotoxic or clastogenic/aneugenic effects on both cell types under the conditions studied. However, caution is advised in the use of this substance by humans, since a significant reduction in viability of HepG2 and a marked decrease in cell viability on normal PBMC were verified.

Hypoxia on the Expression of Hepatoma Upregulated Protein in Prostate Cancer Cells

PubMed Central

Espinoza, Ingrid; Sakiyama, Marcelo J.; Ma, Tangeng; Fair, Logan; Zhou, Xinchun; Hassan, Mohamed; Zabaleta, Jovanny; Gomez, Christian R.

2016-01-01

Hepatoma upregulated protein (HURP) is a multifunctional protein with clinical promise. This protein has been demonstrated to be a predictive marker for the outcome in high-risk prostate cancer (PCa) patients, besides being a resistance factor in PCa. Although changes in oxygen tension (pO2) are associated with PCa aggressiveness, the role of hypoxia in the regulation of tumor progression genes such as HURP has not yet been described. We hypothesized that pO2 alteration is involved in the regulation of HURP expression in PCa cells. In the present study, PCa cells were incubated at 2% O2 (hypoxia) and 20% O2 (normoxia) conditions. Hypoxia reduced cell growth rate of PCa cells, when compared to the growth rate of cells cultured under normoxia (p < 0.05). The decrease in cell viability was accompanied by fivefold (p < 0.05) elevated rate of vascular endothelial growth factor (VEGF) release. The expression of VEGF and the hypoxia-inducible metabolic enzyme carbonic anhydrase 9 were elevated maximally nearly 61-fold and 200-fold, respectively (p < 0.05). Noted in two cell lines (LNCaP and C4-2B) and independent of the oxygen levels, HURP expression assessed at both mRNA and protein levels was reduced. However, the decrease was more pronounced in cells cultured under hypoxia (p < 0.05). Interestingly, the analysis of patients’ specimens by Western blot revealed a marked increase of HURP protein (fivefold), when compared to control (cystoprostatectomy) tissue (p < 0.05). Immunohistochemistry analysis showed an increase in the immunostaining intensity of HURP and the hypoxia-sensitive molecules, hypoxia-inducible factor 1-alpha (HIF-1α), VEGF, and heat-shock protein 60 (HSP60) in association with tumor grade. The data also suggested a redistribution of subcellular localization for HURP and HIF-1α from the nucleus to the cytoplasmic compartment in relation to increasing tumor grade. Analysis of HURP Promoter for HIF-1-binding sites revealed presence

Induction apoptosis of luteolin in human hepatoma HepG2 cells involving mitochondria translocation of Bax/Bak and activation of JNK

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, H.-J.; Wang, C.-J.; Kuo, H.-C.

2005-03-01

Since hepatocellular carcinoma remains a major challenging clinical problem in many parts of the world including Eastern Asia and Southern Africa, it is imperative to develop more effective chemopreventive and chemotherapy agents. Herein, we present an investigation regarding the anticancer potential of luteolin, a natural flavonoid, and the mechanism of its action in human hepatoma HepG2 cells. Using DNA fragmentation assay and nuclear staining assay, it showed that luteolin induced apoptosis of HepG2 cells. Luteolin induced the cytosolic release of cytochrome c and activated CPP32. We found that Bax and Bak translocated to mitochondria apparently, whereas Fas ligand (FasL) wasmore » unchanged after a treatment with luteolin for 3 h. In addition, it showed that c-Jun NH{sub 2}-terminal kinase (JNK) was activated after the treatment of luteolin for 3-12 h. Further investigation showed that a specific JNK inhibitor, SP600125, reduced the activation of CPP 32, the mitochondrial translocation of Bax, as well as the cytosolic release of cytochrome c that induced by luteolin. Finally, the apoptosis induced by luteolin was suppressed by a pretreatment with SP600125 via evaluating annexin V-FITC binding assay. These data suggest that luteolin induced apoptosis via mechanisms involving mitochondria translocation of Bax/Bak and activation of JNK.« less

Overexpression of protein kinase FA/GSK-3 alpha (a proline-directed protein kinase) correlates with human hepatoma dedifferentiation/progression.

PubMed

Yang, S D; Yu, J S; Yang, C C; Lee, S C; Lee, T T; Ni, M H; Kuan, C Y; Chen, H C

1996-05-01

Computer analysis of protein phosphorylation sites sequence revealed that transcriptional factors and viral oncoproteins are prime targets for regulation of proline-directed protein phosphorylation, suggesting an association of the proline-directed protein kinase (PDPK) family with neoplastic transformation and tumorigenesis. In this report, an immunoprecipitate activity assay of protein kinase FA/glycogen synthase kinase-3 alpha (kinase F(A)/GSK-3 alpha) (a member of PDPK family) has been optimized for human hepatoma and used to demonstrate for the first time significantly increased (P < 0.01) activity in poorly differentiated SK-Hep-1 hepatoma (24.2 +/- 2.8 units/mg) and moderately differentiated Mahlavu hepatoma (14.5 +/- 2.2 units/mg) when compared to well differentiated Hep 3B hepatoma (8.0 +/- 2.4 units/mg). Immunoblotting analysis revealed that increased activity of kinase FA/GSK-3 alpha is due to overexpression of the protein. Elevated kinase FA/GSK-3 alpha expression in human hepatoma biopsies relative to normal liver tissue was found to be even more profound. This kinase appeared to be fivefold overexpressed in well differentiated hepatoma and 13-fold overexpressed in poorly differentiated hepatoma when compared to normal liver tissue. Taken together, the results provide initial evidence that overexpression of kinase FA/GSK-3 alpha is involved in human hepatoma dedifferentiation/progression. Since kinase FA/GSK-3 alpha is a PDPK, the results further support a potential role of this kinase in human liver tumorigenesis, especially in its dedifferentiation/progression.

Genotoxicity assessment of membrane concentrates of landfill leachate treated with Fenton reagent and UV-Fenton reagent using human hepatoma cell line.

PubMed

Wang, Guifang; Lu, Gang; Yin, Pinghe; Zhao, Ling; Yu, Qiming Jimmy

2016-04-15

Membrane concentrates of landfill leachates contain organic and inorganic contaminants that could be highly toxic and carcinogenic. In this paper, the genotoxicity of membrane concentrates before and after Fenton and UV-Fenton reagent was assessed. The cytotoxicity and genotoxicity was determined by using the methods of methyltetrazolium (MTT), cytokinesis-block micronucleus (CBMN) and comet assay in human hepatoma cells. MTT assay showed a cytotoxicity of 75% after 24h of exposure to the highest tested concentration of untreated concentrates, and no cytotoxocity for UV-Fenton and Fenton treated concentrates. Both CBMN and comet assays showed increased levels of genotoxicity in cells exposed to untreated concentrates, compared to those occurred in cells exposed to UV-Fenton and Fenton reagent treated concentrates. There was no significant difference between negative control and UV-Fenton treated concentrates for micronucleus and comet assay parameters. UV-Fenton and Fenton treatment, especially the former, were effective methods for degradation of bisphenol A and nonylphenol in concentrates. These findings showed UV-Fenton and Fenton reaction were effective methods for treatment of such complex concentrates, UV-Fenton reagent provided toxicological safety of the treated effluent, and the genotoxicity assays were found to be feasible tools for assessment of toxicity risks of complex concentrates. Copyright © 2016 Elsevier B.V. All rights reserved.

Cytotoxicity of the dicarboximide fungicides, vinclozolin and iprodione, in rat hepatoma-derived Fa32 cells.

PubMed

Dierickx, Paul J

2004-10-01

Dicarboximide fungicides are widely used to control various fungal species. Their primary action is not known, due to a lack of knowledge concerning the mechanism of action of the dicarboximide group. The cytotoxicities of vinclozolin and iprodione in rat hepatoma-derived Fa32 cells were investigated. Cytotoxicity was measured by neutral red uptake inhibition after treatment for 24 hours. Iprodione was more toxic than vinclozolin. Vinclozolin was less toxic in glutathione-depleted cells than in control cells. This was also true for iprodione at lower concentrations, but iprodione became more toxic at higher concentrations. Both the fungicides increased the endogenous glutathione content by 20% after 1 hour. After 24 hours, the glutathione content was doubled by vinclozolin, but was not affected by iprodione. No effect on glutathione S-transferase activity or reactive oxygen species formation could be observed. Cytochrome P450-dependent ethoxyresorufin-O-deethylase and pentoxyresorufin-O-depentylase activities were moderately activated by iprodione and strongly activated by vinclozolin. A glutathione-related cytochrome P450-dependent metabolic attack of vinclozolin and iprodione could be responsible for their cytotoxicity in Fa32 cells. Further research is needed to fully elucidate these (or other) mechanisms.

Synthesis of a novel adamantyl nitroxide derivative with potent anti-hepatoma activity in vitro and in vivo

PubMed Central

Sun, Jin; Wang, Shan; Bu, Wei; Wei, Meng-Ying; Li, Wei-Wei; Yao, Min-Na; Ma, Zhong-Ying; Lu, Cheng-Tao; Li, Hui-Hui; Hu, Na-Ping; Zhang, En-Hu; Yang, Guo-Dong; Wen, Ai-Dong; Zhu, Xiao-He

2016-01-01

In this study, a novel adamantyl nitroxide derivative was synthesized and its antitumor activities in vitro and in vivo were investigated. The adamantyl nitroxide derivative 4 displayed a potent anticancer activity against all the tested human hepatoma cells, especially with IC50 of 68.1 μM in Bel-7404 cells, compared to the positive control 5-FU (IC50=607.7 μM). The significant inhibition of cell growth was also observed in xenograft mouse model, with low toxicity. Compound 4 suppressed the cell migration and invasion, induced the G2/M phase arrest. Further mechanistic studies revealed that compound 4 induced cell death, which was accompanied with damaging mitochondria, increasing the generation of intracellular reactive oxygen species, cleavages of caspase-9 and caspase-3, as well as activations of Bax and Bcl-2. These results confirmed that adamantyl nitroxide derivative exhibited selective antitumor activities via mitochondrial apoptosis pathway in Bel-7404 cells, and would be a potential anticancer agent for liver cancer. PMID:27429843

A Genetically Encoded Probe for Live-Cell Imaging of H4K20 Monomethylation.

PubMed

Sato, Yuko; Kujirai, Tomoya; Arai, Ritsuko; Asakawa, Haruhiko; Ohtsuki, Chizuru; Horikoshi, Naoki; Yamagata, Kazuo; Ueda, Jun; Nagase, Takahiro; Haraguchi, Tokuko; Hiraoka, Yasushi; Kimura, Akatsuki; Kurumizaka, Hitoshi; Kimura, Hiroshi

2016-10-09

Eukaryotic gene expression is regulated in the context of chromatin. Dynamic changes in post-translational histone modification are thought to play key roles in fundamental cellular functions such as regulation of the cell cycle, development, and differentiation. To elucidate the relationship between histone modifications and cellular functions, it is important to monitor the dynamics of modifications in single living cells. A genetically encoded probe called mintbody (modification-specific intracellular antibody), which is a single-chain variable fragment tagged with a fluorescent protein, has been proposed as a useful visualization tool. However, the efficacy of intracellular expression of antibody fragments has been limited, in part due to different environmental conditions in the cytoplasm compared to the endoplasmic reticulum where secreted proteins such as antibodies are folded. In this study, we have developed a new mintbody specific for histone H4 Lys20 monomethylation (H4K20me1). The specificity of the H4K20me1-mintbody in living cells was verified using yeast mutants and mammalian cells in which this target modification was diminished. Expression of the H4K20me1-mintbody allowed us to monitor the oscillation of H4K20me1 levels during the cell cycle. Moreover, dosage-compensated X chromosomes were visualized using the H4K20me1-mintbody in mouse and nematode cells. Using X-ray crystallography and mutational analyses, we identified critical amino acids that contributed to stabilization and/or proper folding of the mintbody. Taken together, these data provide important implications for future studies aimed at developing functional intracellular antibodies. Specifically, the H4K20me1-mintbody provides a powerful tool to track this particular histone modification in living cells and organisms. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Altered expression of CD1d molecules and lipid accumulation in the human hepatoma cell line HepG2 after iron loading.

PubMed

Cabrita, Marisa; Pereira, Carlos F; Rodrigues, Pedro; Cardoso, Elsa M; Arosa, Fernando A

2005-01-01

Iron overload in the liver may occur in clinical conditions such as hemochromatosis and nonalcoholic steatohepatitis, and may lead to the deterioration of the normal liver architecture by mechanisms not well understood. Although a relationship between the expression of ICAM-1, and classical major histocompatibility complex (MHC) class I molecules, and iron overload has been reported, no relationship has been identified between iron overload and the expression of unconventional MHC class I molecules. Herein, we report that parameters of iron metabolism were regulated in a coordinated-fashion in a human hepatoma cell line (HepG2 cells) after iron loading, leading to increased cellular oxidative stress and growth retardation. Iron loading of HepG2 cells resulted in increased expression of Nor3.2-reactive CD1d molecules at the plasma membrane. Expression of classical MHC class I and II molecules, ICAM-1 and the epithelial CD8 ligand, gp180 was not significantly affected by iron. Considering that intracellular lipids regulate expression of CD1d at the cell surface, we examined parameters of lipid metabolism in iron-loaded HepG2 cells. Interestingly, increased expression of CD1d molecules by iron-loaded HepG2 cells was associated with increased phosphatidylserine expression in the outer leaflet of the plasma membrane and the presence of many intracellular lipid droplets. These data describe a new relationship between iron loading, lipid accumulation and altered expression of CD1d, an unconventional MHC class I molecule reported to monitor intracellular and plasma membrane lipid metabolism, in the human hepatoma cell line HepG2.

[Effect of depsides salts from Salvia miltiorrhiza on human hepatoma cell line SMMC-7721 subcutaneous xenografts in nude mice].

PubMed

Li, Xiangping; Song, Zhouye; Zhong, Haiying; Gong, Zhicheng; Yin, Tao; Zhang, Zanling; Zhou, Boting

2015-02-01

To exlpore the eff ect of depsides salts from Salvia miltiorrhiza on human hepatoma cell line SMMC-7721 xenograft tumors and the possible mechanisms. A total of 36 nude mice were divided into 6 groups: A model group, a negative control group, a positive control group, and 3 treatment groups at low, middle or high dose (n=6). The tumor model of nude mice was given depsides salts at a dose of 10, 20 or 50 mg/kg every 3 day for 16 days. Then samples of subcutaneous tumors in nude mice were collected. The morphological changes of tumor samples were observed by HE staining and the expression of vascular endothelial growth factor (VEGF) and the tumor antigen Ki67 was detected by immunohistochemical method. The tumor growth was inhibited by all doses of depsides salts. The morphology of tumors was shrinkage, broken and irregularly arranged compared with the tumors in the model group and the negative control group. Morphological changes were more obvious in tumors with treatment at high dose. Expression of VEGF and Ki67 in treatment groups and the positive control group were lower than that in the model group and the negative control group, with a significant difference (P<0.05). Depsides salts from Salvia miltiorrhiza can inhibit the growth of human hepatoma cell line SMMC-7721 tumor in nude mice, which is related to the inhibition of Ki67 and VEGF.

Icaritin inhibits the expression of alpha-fetoprotein in hepatitis B virus-infected hepatoma cell lines through post-transcriptional regulation.

PubMed

Zhang, Chao; Li, Hui; Jiang, Wei; Zhang, Xiaowei; Li, Gang

2016-12-13

Although it has showed that icaritin can apparently suppress growth of HCC by reducing the level of AFP, the intrinsic mechanism remains unclear. In this study, we explored the possible mechanism of miRNAs on post-transcriptional regulation of AFP gene, as well as the effects of HBV infection and icaritin in hepatoma cells. The results showed that miR-620, miR-1236 and miR-1270 could bind target sites in the range of 9-18 nt and 131-151 nt downstream of the stop codon in the AFP mRNA 3'-UTR to suppress the expression of AFP. Mutation of these target sites could reverse the effects of these miRNAs. Icaritin (10 μM) might reduce the stability and translational activity of AFP mRNA by increasing the expression levels of these mentioned miRNAs. HBV infection resulted in apparent decreases of these miRNAs and, consequently, increased AFP expression. The results indicated that miR-620, miR-1236 and miR-1270 are critical factors in the post-transcriptional regulation of AFP. Icaritin can counteract the effect of HBV. These findings will contribute to full understanding of the regulatory mechanism of AFP expression in hepatoma cells. And also it revealed a synergistic mechanism of HBV infection and elevation of AFP in the pathogenesis of HCC, as well as the potential clinical significance of icaritin on the therapy of HCC induced by HBV.

Cytotoxic effect induced by retinoic acid loaded into galactosyl-sphingosine containing liposomes on human hepatoma cell lines.

PubMed

Díaz, Cecilia; Vargas, Ernesto; Gätjens-Boniche, Omar

2006-11-15

Two retinoids, ATRA and 13cisRA, were incorporated into liposomes of different composition and charge and added to two hepatoma cell lines with different degree of transformation to measure cytotoxicity by MTT assay. Retinoid-free cationic liposomes were more toxic than the other kinds (anionic and made only of PC) but were also the best delivery system for retinoic acid to induce specific cytotoxic effects on these tumor hepatoma cell lines. Galactosyl-sphingosine containing cationic liposomes increased the cytotoxic effect induced by ATRA on Hep3B cells when compared to glucosyl-sphingosine cationic liposomes, but did not improve the effect induced by free retinoid or ATRA loaded into liposomes without glycolipids. This suggests that in this cell line, ATRA is being incorporated by a mechanism mediated by the asialoglycoprotein receptor, but at the same time, non-specific sugar-independent capture is also taking place as well as free diffusion of ATRA directly through the membrane. Galactose-specific effect was not observed in HepG2 cells treated with ATRA or both cell lines treated with 13cisRA. In fact, treatment of HepG2 cells with retinoids entrapped into liposomes likely induces proliferation instead of cytotoxicity, a result that interferes with the measurement of cell death by MTT. Compared to the specific effect of ATRA entrapped into cationic liposomes, vesicles made only by PC, did not mediate a specific mechanism, since differences between ATRA in galactosyl- and glucosyl-shpingosine PC-liposomes were not statistically significant. The specific mechanism was not present in the myoblastic cell line C2C12, where ATRA incorporated into galactosyl- and glucosyl-sphingosine containing cationic and PC-liposomes, was able to induce cytotoxicity at the same extent. Micelles containing ATRA and galactosyl-sphingosine had a significantly more toxic effect than the retinoid administered together with glucosyl-sphingosine, in Hep3B cells. Also, micelles containing

The spleen can influence the metastasis of AH130 hepatoma cells in rats.

PubMed

Toyonaga, M; Hiraoka, T; Tanaka, H; Miyauchi, Y

1993-06-01

The effect of pathophysiological conditions due to disturbance of the spleen is still unclear. We studied the effects of splenectomy in normal and methylcellulose-induced hypersplenic rats on the development of pulmonary metastases created by intravenous injection of ascites containing AH130 hepatoma cells from male Hos-Donryu rats. Growth of metastatic lesions in the lung was not affected by splenectomy in normal rats, but was increased by splenectomy in hypersplenic rats. Overall, there were fewer pulmonary metastases in rats with hypersplenism, but after splenectomy rats with hypersplenism had a significantly greater number of metastases than did normal rats. The metastases rate correlated somewhat with changes in the blood coagulation and T lymphocyte profile. There is a relationship between the spleen and formation of metastases in cancer. Formation of metastases in the lung was affected most by splenectomy in hypersplenism. To elucidate the mechanism by which metastases are formed in the lung under these pathologic conditions, further studies on the exact role of the spleen are required.

Preliminary study of histamine H4 receptor expressed on human CD4+ T cells and its immunomodulatory potency in the IL-17 pathway of psoriasis.

PubMed

Han, Song Hee; Hur, Min Seok; Kim, Min Jung; Kim, Bo Mi; Kim, Kyoung Woon; Kim, Hae Rim; Choe, Yong Beom; Ahn, Kyu Joong; Lee, Yang Won

2017-10-01

Previous studies have shown the expression of histamine H 4 receptor (H4R) on CD4 + T cells, especially human CD4 + T h 2-polarized T cells. This study aimed to investigate the role of H4R on these effector T cells in psoriasis. We enrolled three patients each with active psoriasis, inactive psoriasis, scalp seborrheic dermatitis, and three normal controls, and compared the basal expression of H4R mRNA in their peripheral blood CD4 + T cells. Then, we identified H4R expression in dermal CD4 + T cells. Furthermore, we investigated H4R expression after stimulating separated peripheral blood CD4 + T cells with several inflammatory cytokines. The results showed higher H4R expression in the active psoriasis group compared to the inactive psoriasis group. It was interesting that interleukin (IL)-23, which is a representative cytokine contributing to T h 17 cell differentiation, stimulated H4R expression significantly. After adding a selective H4R antagonist (JNJ-7777120) while the CD4 + T cells were polarized into T h 17 cells, we observed a tendency toward suppressed IL-17 secretion. Histamine stimulation influences the IL-17 pathway in psoriasis via the fourth histamine receptor subtype, H4R, on CD4 + T cells. The immunomodulatory roles of H4R suggest its potency as a new therapeutic target for obstinate psoriasis. Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

4β-Hydroxywithanolide E from Physalis peruviana (golden berry) inhibits growth of human lung cancer cells through DNA damage, apoptosis and G2/M arrest

PubMed Central

2010-01-01

Background The crude extract of the fruit bearing plant, Physalis peruviana (golden berry), demonstrated anti-hepatoma and anti-inflammatory activities. However, the cellular mechanism involved in this process is still unknown. Methods Herein, we isolated the main pure compound, 4β-Hydroxywithanolide (4βHWE) derived from golden berries, and investigated its antiproliferative effect on a human lung cancer cell line (H1299) using survival, cell cycle, and apoptosis analyses. An alkaline comet-nuclear extract (NE) assay was used to evaluate the DNA damage due to the drug. Results It was shown that DNA damage was significantly induced by 1, 5, and 10 μg/mL 4βHWE for 2 h in a dose-dependent manner (p < 0.005). A trypan blue exclusion assay showed that the proliferation of cells was inhibited by 4βHWE in both dose- and time-dependent manners (p < 0.05 and 0.001 for 24 and 48 h, respectively). The half maximal inhibitory concentrations (IC50) of 4βHWE in H1299 cells for 24 and 48 h were 0.6 and 0.71 μg/mL, respectively, suggesting it could be a potential therapeutic agent against lung cancer. In a flow cytometric analysis, 4βHWE produced cell cycle perturbation in the form of sub-G1 accumulation and slight arrest at the G2/M phase with 1 μg/mL for 12 and 24 h, respectively. Using flow cytometric and annexin V/propidium iodide immunofluorescence double-staining techniques, these phenomena were proven to be apoptosis and complete G2/M arrest for H1299 cells treated with 5 μg/mL for 24 h. Conclusions In this study, we demonstrated that golden berry-derived 4βHWE is a potential DNA-damaging and chemotherapeutic agent against lung cancer. PMID:20167063

4beta-Hydroxywithanolide E from Physalis peruviana (golden berry) inhibits growth of human lung cancer cells through DNA damage, apoptosis and G2/M arrest.

PubMed

Yen, Ching-Yu; Chiu, Chien-Chih; Chang, Fang-Rong; Chen, Jeff Yi-Fu; Hwang, Chi-Ching; Hseu, You-Cheng; Yang, Hsin-Ling; Lee, Alan Yueh-Luen; Tsai, Ming-Tz; Guo, Zong-Lun; Cheng, Yu-Shan; Liu, Yin-Chang; Lan, Yu-Hsuan; Chang, Yu-Ching; Ko, Ying-Chin; Chang, Hsueh-Wei; Wu, Yang-Chang

2010-02-18

The crude extract of the fruit bearing plant, Physalis peruviana (golden berry), demonstrated anti-hepatoma and anti-inflammatory activities. However, the cellular mechanism involved in this process is still unknown. Herein, we isolated the main pure compound, 4beta-Hydroxywithanolide (4betaHWE) derived from golden berries, and investigated its antiproliferative effect on a human lung cancer cell line (H1299) using survival, cell cycle, and apoptosis analyses. An alkaline comet-nuclear extract (NE) assay was used to evaluate the DNA damage due to the drug. It was shown that DNA damage was significantly induced by 1, 5, and 10 microg/mL 4betaHWE for 2 h in a dose-dependent manner (p < 0.005). A trypan blue exclusion assay showed that the proliferation of cells was inhibited by 4betaHWE in both dose- and time-dependent manners (p < 0.05 and 0.001 for 24 and 48 h, respectively). The half maximal inhibitory concentrations (IC50) of 4betaHWE in H1299 cells for 24 and 48 h were 0.6 and 0.71 microg/mL, respectively, suggesting it could be a potential therapeutic agent against lung cancer. In a flow cytometric analysis, 4betaHWE produced cell cycle perturbation in the form of sub-G1 accumulation and slight arrest at the G2/M phase with 1 microg/mL for 12 and 24 h, respectively. Using flow cytometric and annexin V/propidium iodide immunofluorescence double-staining techniques, these phenomena were proven to be apoptosis and complete G2/M arrest for H1299 cells treated with 5 microg/mL for 24 h. In this study, we demonstrated that golden berry-derived 4betaHWE is a potential DNA-damaging and chemotherapeutic agent against lung cancer.

Properties of the Guin ungrouped iron meteorite - The origin of Guin and of group-IIE irons

NASA Astrophysics Data System (ADS)

Rubin, A. E.; Jerde, E. A.; Zong, P.; Wasson, J. T.; Westcott, J. W.; Mayeda, T. K.; Clayton, R. N.

1986-01-01

The composition and structure of the Guin ungrouped iron meteorite inclusions have been investigated experimentally. The structural characteristics of polished and etched slabs of the meteorite were studied microscopically in reflected light. Modal abundances of troilite nodules and silicate inclusions were determined by weighing paper traces. The bulk composition of the silicate inclusions was calculated by combining modal phase abundances and mineral compositions. It is found that the largest silicate inclusion (2 x 4 cm) consists mostly of a shock-melted plagioclase-rich matrix surrounding large, partly melted augite grains. The oxygen isotopic composition of the inclusion is near that of LL chondrites. The inclusion is found to be similar in composition to selected melt pocket glasses in ordinary chondrites produced in situ by preferential melting of plagioclase rock due to shock compression. It is suggested that the Guin assemblage was formed by impact melting on a chondritic parent body. Silicate inclusions in IIE irons share many of the compositional and petrological characteristics of the Guin inclusions, indicating that IIE irons also formed by impact-melting of chondritic materials. Black and white photomicrographs of the silicate inclusions are provided.

Caspase-8 acts as a key upstream executor of mitochondria during justicidin A-induced apoptosis in human hepatoma cells.

PubMed

Su, Chun-Li; Huang, Lynn L H; Huang, Li-Min; Lee, Jenq-Chang; Lin, Chun-Nan; Won, Shen-Jeu

2006-05-29

Justicia procumbens is a traditional Taiwanese herbal remedy used to treat fever, pain, and cancer. Justicidin A, isolated from Justicia procumbens, has been reported to suppress in vitro growth of several tumor cell lines as well as hepatoma cells. In this study, justicidin A activated caspase-8 to increase tBid, disrupted mitochondrial membrane potential (Delta psi(m)), and caused the release of cytochrome c and Smac/DIABLO in Hep 3B and Hep G2 cells. Justicidin A also reduced Bcl-x(L) and increased Bax and Bak in mitochondria. Caspase-8 inhibitor (Z-IETD) attenuated the justicidin A-induced disruption of Delta psi(m). Growth of Hep 3B implanted in NOD-SCID mice was suppressed significantly by oral justicidin A (20 mg/kg/day). These results indicate that justicidin A-induced apoptosis in these cells proceeds via caspase-8 and is followed by mitochondrial disruption.

The dietary flavonoid kaempferol effectively inhibits HIF-1 activity and hepatoma cancer cell viability under hypoxic conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mylonis, Ilias; Lakka, Achillia; Tsakalof, Andreas

Research highlights: {yields} Kaempferol inhibits HIF-1 activity in hepatocarcinoma cells; {yields} Kaempferol causes cytoplasmic mislocalization of HIF-1{alpha} by impairing the MAPK pathway. {yields} Viability of hepatocarcinoma cells under hypoxia is reduced by kaempferol. -- Abstract: Hepatocellular carcinoma (HCC) is characterized by high mortality rates and resistance to conventional treatment. HCC tumors usually develop local hypoxia, which stimulates proliferation of cancer cells and renders them resilient to chemotherapy. Adaptation of tumor cells to the hypoxic conditions depends on the hypoxia-inducible factor 1 (HIF-1). Over-expression of its regulated HIF-1{alpha} subunit, an important target of anti-cancer therapy, is observed in many cancers includingmore » HCC and is associated with severity of tumor growth and poor patient prognosis. In this report we investigate the effect of the dietary flavonoid kaempferol on activity, expression levels and localization of HIF-1{alpha} as well as viability of human hepatoma (Huh7) cancer cells. Treatment of Huh7 cells with kaempferol under hypoxic conditions (1% oxygen) effectively inhibited HIF-1 activity in a dose-dependent manner (IC{sub 50} = 5.16 {mu}M). The mechanism of this inhibition did not involve suppression of HIF-1{alpha} protein levels but rather its mislocalization into the cytoplasm due to inactivation of p44/42 MAPK by kaempferol (IC{sub 50} = 4.75 {mu}M). Exposure of Huh7 cells to 10 {mu}{Mu} kaempferol caused significant reduction of their viability, which was remarkably more evident under hypoxic conditions. In conclusion, kaempferol, a non-toxic natural food component, inhibits both MAPK and HIF-1 activity at physiologically relevant concentrations (5-10 {mu}M) and suppresses hepatocarcinoma cell survival more efficiently under hypoxia. It has, therefore, potential as a therapeutic or chemopreventive anti-HCC agent.« less

EML4-ALK induces epithelial-mesenchymal transition consistent with cancer stem cell properties in H1299 non-small cell lung cancer cells.

PubMed

Guo, Fuchun; Liu, Xiaoke; Qing, Qin; Sang, Yaxiong; Feng, Chengjun; Li, Xiaoyu; Jiang, Li; Su, Pei; Wang, Yongsheng

2015-04-10

The echinoderm microtubule-associated protein-like 4(EML4)--anaplastic lymphoma kinase (ALK) fusion gene has been identified as a driver mutation in non-small-cell lung cancer (NSCLC). However, the role of EML4-ALK in malignant transformation is not entirely clear. Here, for the first time, we showed that H1299 NSCLC cells stably expressing EML4-ALK acquire EMT phenotype, associated with enhanced invasive migration and increased expression of EMT-inducing transcription factors. H1299-EML4-ALK cells also displayed cancer stem cell-like properties with a concomitant up-regulation of CD133 and enhanced ability of mammospheres formation. Moreover, we found that inhibition of ERK1/2 reversed EMT induced by EML4-ALK in H1299 cells. Taken together, these results suggested that EML4-ALK induced ERK activation is mechanistically associated with EMT phenotype. Thus, inhibition of ERK signaling pathway could be a potential strategy in treatment of NSCLC patients with EML4-ALK translocation. Copyright © 2015 Elsevier Inc. All rights reserved.

Certain and progressive methylation of histone H4 at lysine 20 during the cell cycle.

PubMed

Pesavento, James J; Yang, Hongbo; Kelleher, Neil L; Mizzen, Craig A

2008-01-01

Methylation of histone H4 at lysine 20 (K20) has been implicated in transcriptional activation, gene silencing, heterochromatin formation, mitosis, and DNA repair. However, little is known about how this modification is regulated or how it contributes to these diverse processes. Metabolic labeling and top-down mass spectrometry reveal that newly synthesized H4 is progressively methylated at K20 during the G(2), M, and G(1) phases of the cell cycle in a process that is largely inescapable and irreversible. Approximately 98% of new H4 becomes dimethylated within two to three cell cycles, and K20 methylation turnover in vivo is undetectable. New H4 is methylated regardless of prior acetylation, and acetylation occurs predominantly on K20-dimethylated H4, refuting the hypothesis that K20 methylation antagonizes H4 acetylation and represses transcription epigenetically. Despite suggestions that it is required for normal mitosis and cell cycle progression, K20 methylation proceeds normally during colchicine treatment. Moreover, delays in PR-Set7 synthesis and K20 methylation which accompany altered cell cycle progression during sodium butyrate treatment appear to be secondary to histone hyperacetylation or other effects of butyrate since depletion of PR-Set7 did not affect cell cycle progression. Together, our data provide an unbiased perspective of the regulation and function of K20 methylation.

Effect of Daytime Blue-enriched LED Light on the Nighttime Circadian Melatonin Inhibition of Hepatoma 7288CTC Warburg Effect and Progression.

PubMed

Dauchy, Robert T; Wren-Dail, Melissa A; Dupepe, Lynell M; Hill, Steven M; Xiang, Shulin; Anbalagan, Muralidharan; Belancio, Victoria P; Dauchy, Erin M; Blask, David E

2018-06-06

Liver cancer is the second leading cause of cancer death worldwide. Metabolic pathways within the liver and liver cancersare highly regulated by the central circadian clock in the suprachiasmatic nuclei (SCN). Daily light and dark cycles regulate the SCN-driven pineal production of the circadian anticancer hormone melatonin and temporally coordinate circadianrhythms of metabolism and physiology in mammals. In previous studies, we demonstrated that melatonin suppresses linoleicacid metabolism and the Warburg effect (aerobic glycolysis)in human breast cancer xenografts and that blue-enriched light(465-485 nm) from light-emitting diode lighting at daytime (bLAD) amplifies nighttime circadian melatonin levels in ratsby 7-fold over cool white fluorescent (CWF) lighting. Here we tested the hypothesis that daytime exposure of tissue-isolatedMorris hepatoma 7288CTC-bearing male rats to bLAD amplifies the nighttime melatonin signal to enhance the inhibition oftumor growth. Compared with rats housed under a 12:12-h light:dark cycle in CWF light, rats in bLAD light evinced a 7-fold higher peak plasma melatonin level at the mid-dark phase; in addition, high melatonin levels were prolonged until 4 h intothe light phase. After implantation of tissue-isolated hepatoma 7288CTC xenografts, tumor growth rates were markedly delayed,and tumor cAMP levels, LA metabolism, the Warburg effect, and growth signaling activities were decreased in rats inbLAD compared with CWF daytime lighting. These data show that the increased nighttime circadian melatonin levels dueto bLAD exposure decreases hepatoma metabolic, signaling, and proliferative activities beyond what occurs after normalmelatonin signaling under CWF light.

Discovery of (4-bromophenyl)(3-hydroxy-4-methoxyphenyl)methanone through upregulating hTERT induces cell apoptosis and ERS

PubMed Central

Cheng, Xiu; Shi, Jing Bo; Liu, Hao; Chen, Liu Zeng; Wang, Yang; Tang, Wen Jian; Liu, Xin Hua

2017-01-01

Dominant-negative mutants of telomerase hTERT were demonstrated to have selective effects in tumor cells. However, no any effective and highly selective hTERT inhibitor has been developed so far. We focused on developing new hTERT modulators and synthesized a small molecular compound, named (4-bromophenyl)(3-hydroxy-4-methoxyphenyl)methanone. Our in vitro studies found that title compound showed high inhibitory activity against telomerase, had high antiproliferative capacity on SMMC-7721 cells with IC50 value 88 nm, and had no obvious toxic effect on human normal hepatocyte cells with IC50 value 10 μM. Our in vivo studies showed that this compound significantly inhibited tumor growth in xenograft tumor models. The further molecular mechanisms of title compound inhibition SMMC-7721 cell proliferation by modulating hTERT were explored; the results showed that endoplasmic reticulum stress (ERS) through ER over response (EOR) activates the expression of hTERT, and then induces ERS, which is believed to be intricately associated with oxidative stress and mitochondrial dysfunction, resulting in apoptotic cell death, thereby modulating the expression of downstream signaling molecules including CHOP (CAAT/enhancer-binding protein homologous protein)) and mitochondrion pathway of apoptosis, leading to inhibition of cell proliferation. PMID:28837145

The Finding of a Group IIE Phospholipase A2 Gene in a Specified Segment of Protobothrops flavoviridis Genome and Its Possible Evolutionary Relationship to Group IIA Phospholipase A2 Genes

PubMed Central

Yamaguchi, Kazuaki; Chijiwa, Takahito; Ikeda, Naoki; Shibata, Hiroki; Fukumaki, Yasuyuki; Oda-Ueda, Naoko; Hattori, Shosaku; Ohno, Motonori

2014-01-01

The genes encoding group IIE phospholipase A2, abbreviated as IIE PLA2, and its 5' and 3' flanking regions of Crotalinae snakes such as Protobothrops flavoviridis, P. tokarensis, P. elegans, and Ovophis okinavensis, were found and sequenced. The genes consisted of four exons and three introns and coded for 22 or 24 amino acid residues of the signal peptides and 134 amino acid residues of the mature proteins. These IIE PLA2s show high similarity to those from mammals and Colubridae snakes. The high expression level of IIE PLA2s in Crotalinae venom glands suggests that they should work as venomous proteins. The blast analysis indicated that the gene encoding OTUD3, which is ovarian tumor domain-containing protein 3, is located in the 3' downstream of IIE PLA2 gene. Moreover, a group IIA PLA2 gene was found in the 5' upstream of IIE PLA2 gene linked to the OTUD3 gene (OTUD3) in the P. flavoviridis genome. It became evident that the specified arrangement of IIA PLA2 gene, IIE PLA2 gene, and OTUD3 in this order is common in the genomes of humans to snakes. The present finding that the genes encoding various secretory PLA2s form a cluster in the genomes of humans to birds is closely related to the previous finding that six venom PLA2 isozyme genes are densely clustered in the so-called NIS-1 fragment of the P. flavoviridis genome. It is also suggested that venom IIA PLA2 genes may be evolutionarily derived from the IIE PLA2 gene. PMID:25529307

Chronic ecotoxic effects to Pseudomonas putida and Vibrio fischeri, and cytostatic and genotoxic effects to the hepatoma cell line (HepG2) of ofloxacin photo(cata)lytically treated solutions.

PubMed

Vasquez, M I; Garcia-Käufer, M; Hapeshi, E; Menz, J; Kostarelos, K; Fatta-Kassinos, D; Kümmerer, K

2013-04-15

Ofloxacin (OFL), a broad-spectrum and widespread-used photolabile fluoroquinolone, is frequently found in treated wastewaters, aquatic and terrestrial ecosystems leading to increasing concern during the past decades regarding its effects to the environment and human health. The elimination of OFL and other xenobiotics by the application of advanced oxidation processes using photolytic (PL) and photocatalytic (PC) treatments seems promising. However, an integrated assessment scheme is needed, in which, not only the removal of the parent compound, but also the effects of the photo-transformation products (PTPs) are investigated. For this purpose, in the present study, a chronic ecotoxic assessment using representative bacteria of marine and terrestrial ecosystems and a cytostatic and genotoxic evaluation using hepatoma cell line were performed. PL and PC treatments of OFL were applied using UV radiation. The photo-transformation of OFL during the treatments was monitored by DOC measurements and UPLC-MS/MS analysis. The chronic ecotoxicity of OFL and treated samples was evaluated using Pseudomonas putida and Vibrio fischeri; whereas the cytostasis and genotoxicity were estimated by the cytokinesis-block micronucleus assay (CBMN). The main results suggest that photo-transformation of OFL took place during these treatments since the concentration of OFL decreased when the irradiation time increased, as quantified by UPLC-MS/MS analysis, and this was not coupled with an analogous DOC removal. Furthermore, nine compounds were identified as probable PTPs formed through piperazinyl dealkylation and decarboxylation. The ecotoxicity of treated solutions to the bacteria studied decreased while the cytostasis to the hepatoma cell line remained at low levels during both treatments. However, the genotoxicity to the hepatoma cell line demonstrated a different pattern in which treated samples induced a greater number of MNi for the 4-16 min of irradiation (p<0.05) during both

Cancer cell-associated cytoplasmic B7–H4 is induced by hypoxia through hypoxia-inducible factor-1α and promotes cancer cell proliferation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jeon, You-Kyoung; Advanced Research Center for Multiple Myeloma, Inje University College of Medicine, Busan 614-735; Park, Sae-Gwang

2015-04-03

Aberrant B7–H4 expression in cancer tissues serves as a novel prognostic biomarker for poor survival in patients with cancer. However, the factor(s) that induce cancer cell-associated B7–H4 remain to be fully elucidated. We herein demonstrate that hypoxia upregulates B7–H4 transcription in primary CD138{sup +} multiple myeloma cells and cancer cell lines. In support of this finding, analysis of the Multiple Myeloma Genomics Portal (MMGP) data set revealed a positive correlation between the mRNA expression levels of B7–H4 and the endogenous hypoxia marker carbonic anhydrogenase 9. Hypoxia-induced B7–H4 expression was detected in the cytoplasm, but not in cancer cell membranes. Chromatinmore » immunoprecipitation analysis demonstrated binding of hypoxia-inducible factor-1α (HIF-1α) to proximal hypoxia-response element (HRE) sites within the B7–H4 promoter. Knockdown of HIF-1α and pharmacological inhibition of HIF-1α diminished B7–H4 expression. Furthermore, knockdown of cytoplasmic B7–H4 in MCF-7 decreased the S-phase cell population under hypoxia. Finally, MMGP analysis revealed a positive correlation between the transcript levels of B7–H4 and proliferation-related genes including MKI67, CCNA1, and Myc in several patients with multiple myeloma. Our results provide insight into the mechanisms underlying B7–H4 upregulation and its role in cancer cell proliferation in a hypoxic tumor microenvironment. - Highlights: • Hypoxia upregulates B7–H4 transcription and protein expression. • Hypoxia-induced B7–H4 is detected in the cytoplasm, but not on membrane. • ChIP assay reveals a binding of HIF-1α to B7–H4 promoter at HRE site. • Knockdown and pharmacological inhibition of HIF-1α reduce B7–H4 expression. • B7–H4 knockdown decrease the number of cells in S-phase of cell cycle.« less

Modulation of the DNA repair system and ATR-p53 mediated apoptosis is relevant for tributyltin-induced genotoxic effects in human hepatoma G2 cells.

PubMed

Li, Bowen; Sun, Lingbin; Cai, Jiali; Wang, Chonggang; Wang, Mengmeng; Qiu, Huiling; Zuo, Zhenghong

2015-01-01

The toxic effects of tributyltin (TBT) have been extensively documented in several types of cells, but the molecular mechanisms related to the genotoxic effects of TBT have still not been fully elucidated. Our study showed that exposure of human hepatoma G2 cells to 1-4 μmol/L TBT for 3 hr caused severe DNA damage in a concentration-dependent manner. Moreover, the expression levels of key DNA damage sensor genes such as the replication factor C, proliferating cell nuclear antigen and poly (ADP-ribose) polymerase-1 were inhabited in a concentration-dependent manner. We further demonstrated that TBT induced cell apoptosis via the p53-mediated pathway, which was most likely activated by the ataxia telangiectasia mutated and rad-3 related (ATR) protein kinase. The results also showed that cytochrome c, caspase-3, caspase-8, caspase-9, and the B-cell lymphoma 2 were involved in this process. Taken together, we demonstrated for the first time that the inhibition of the DNA repair system might be more responsible for TBT-induced genotoxic effects in cells. Then the generated DNA damage induced by TBT initiated ATR-p53-mediated apoptosis. Copyright © 2014. Published by Elsevier B.V.

The role of the 2H4 molecule in the generation of suppressor function in Con A-activated T cells.

PubMed

Morimoto, C; Letvin, N L; Rudd, C E; Hagan, M; Takeuchi, T; Schlossman, S F

1986-11-15

The molecular basis for the suppression generated in a concanavalin A (Con A)-activated T cell culture remains unknown. In this study, we have attempted to determine whether the 2H4 and 4B4 molecules on Con A-activated T cells play some role in the generation of suppression by such cells. We have shown that Con A-activated suppressor cells belong to the 2H4+ subset of T cells but not the 4B4+ (2H4-) subset. Con A-activated T cells exerted their optimal suppressor function on day 2 in culture, a time at which the expression of 2H4 on such cells was maximal and 4B4 was minimal. Furthermore, the stimulation of T cells with the higher concentration of Con A generated the stronger suppressor function. At the same time, both 2H4 expression and density were increased and 4B4 expression and density were decreased on such Con A-activated T cells. More importantly, the treatment of Con A-activated T cells with anti-2H4 antibody but not with anti-4B4, anti-TQ1, or anti-T4 antibodies can block the suppressor function of such cells. Taken together, the above results strongly suggest that the 2H4 molecule itself may be involved in the generation of suppressor function in Con A-activated T cells. The 2H4 antigen on such cells was shown to be comprised of 220,000 and 200,000 m.w. glycoproteins. Thus this study indicates that the 220,000 and 200,000 m.w. structure of the 2H4 molecule may itself play a crucial role in the generation of suppressor signals of Con A-activated cells.

Transcriptional regulation of human paraoxonase 1 by PXR and GR in human hepatoma cells.

PubMed

Ponce-Ruiz, N; Rojas-García, A E; Barrón-Vivanco, B S; Elizondo, G; Bernal-Hernández, Y Y; Mejía-García, A; Medina-Díaz, I M

2015-12-25

Human paraoxonase 1 (PON1) is A-esterase synthesized in the liver and secreted into the plasma, where it associates with HDL. PON1 acts as an antioxidant preventing lipid oxidation and detoxifies a wide range of substrates, including organophosphate compounds. The variability of PON1 (enzyme activity/serum levels) has been attributed to internal and external factors. However, the molecular mechanisms involved in the transcriptional regulation of PON1 have not been well-studied. The aim of this study was to evaluate and characterize the transcriptional activation of PON1 by nuclear receptors (NR) in human hepatoma cells. In silico analysis was performed on the promoter region of PON1 to determine the response elements of NR. Real-time PCR was used to evaluate the effect of specific NR ligands on the mRNA levels of genes regulated by NR and PON1. The results indicated that NR response elements had 95% homology to pregnenolone (PXR), glucocorticoids (GR), retinoic acid (RXR) and peroxisomes proliferator-activated receptor alpha (PPARα). Treatments with Dexamethasone (GR ligand), Rifampicin (PXR ligand) and TCDD (AhR ligand) increased the mRNA levels of PON1 at 24 and 48 h. We showed that the activation of GR by Dexamethasone results in PON1 gene induction accompanied by an increase in activity levels. In conclusion, these results demonstrate that GR regulates PON1 gene transcription through directly binding to NR response elements at -95 to -628 bp of the PON1 promoter. This study suggests new molecular mechanisms for the transcriptional regulation of PON1 through a process involving the activation of PXR. Copyright © 2015 Elsevier B.V. All rights reserved.

Role of intracellular Ca2+ signal in the ascorbate-induced apoptosis in a human hepatoma cell line.

PubMed

Lee, Yong Soo

2004-12-01

Although ascorbate (vitamin C) has been shown to have anti-cancer actions, its effect on human hepatoma cells has not yet been investigated, and thus, the exact mechanism of this action is not fully understood. In this study, the mechanism by which ascorbate induces apoptosis using HepG2 human hepatoblastoma cells is investigated. Ascorbate induced apoptotic cell death in a dose-dependent manner in the cells, was assessed through flow cytometric analysis. Contrary to expectation, ascorbate did not alter the cellular redox status, and treatment with antioxidants (N-acetyl cysteine and N,N-diphenyl-p-phenylenediamine) had no influence on the ascorbate-induced apoptosis. However, ascorbate induced a rapid and sustained increase in intracellular Ca2+ concentration. EGTA, an extracellular Ca2+ chelator did not significantly alter the ascorbate-induced intracellular Ca2+ increase and apoptosis, whereas dantrolene, an intracellular Ca2+ release blocker, completely blocked these actions of ascorbate. In addition, phospholipase C (PLC) inhibitors (U-73122 and manoalide) significantly suppressed the intracellular Ca2+ release and apoptosis induced by ascorbate. Collectively, these results suggest that ascorbate induced apoptosis without changes in the cellular redox status in HepG2 cells, and that the PLC-coupled intracellular Ca2+ release mechanism may mediate ascorbate-induced apoptosis.

[Knockdown of STAT3 inhibits proliferation and migration of HepG2 hepatoma cells induced by IFN1].

PubMed

Li, Xiaofang; Wang, Yuqi; Yan, Ben; Fang, Peipei; Ma, Chao; Xu, Ning; Fu, Xiaoyan; Liang, Shujuan

2018-02-01

Objective To prepare lentiviruses expressing shRNA sequences targeting human signal transducer and activator of transcription 3 (STAT3) and detect the effect of STAT3 knockdown on type I interferon (IFN1)-induced proliferation and migration in HepG2 cells. Methods Four STAT3-targeting shRNA sequences (shRNA1-shRNA4) and one control sequence (Ctrl shRNA) were selected and cloned respectively into pLKO.1-sp6-pgk-GFP to construct shRNA-expressing vectors. Along with backbone psPAX2 and pMD2.G vectors, they were separately transfected into HEK293T cells to prepare lentiviruses. HepG2 cells were infected with the lentiviruses. Cytoplastic STAT3 level was detected by Western blotting to screen effective shRNA sequence(s) targeting STAT3. Proliferation and migration of HepG2 cells were analyzed by CCK-8 assay and Transwell TM migration and scratching assay, respectively. To detect the effect of IFN1 on cell proliferation and migration of HepG2 cells, the cells were treated with 2000 U/mL IFNα2b for indicated time and the activation of IFN-triggered STAT1 signal transduction was assayed by Western blotting. Results Two most effective STAT3-targeting shRNA sequences shRNA1 and shRNA2 were selected, and the expression of both STAT3 shRNA significantly decreased proliferation and migration of HepG2 cells. When treated with IFNα2b, 2000 U/mL of IFN1 showed more competent in attenuating growth and migration of HepG2 cells. Our data further proved that knockdown of STAT3 increased the phosphorylation of STAT1, and IFNα2b further enhanced the activation of STAT1 signaling in HepG2 cells. Conclusion Knockdown of STAT3 inhibits cell migration and growth, and rescues IFN response through up-regulating STAT1 signal transduction in HepG2 hepatoma cells.

Knock down of GCN5 histone acetyltransferase by siRNA decreases ethanol-induced histone acetylation and affects differential expression of genes in human hepatoma cells.

PubMed

Choudhury, Mahua; Pandey, Ravi S; Clemens, Dahn L; Davis, Justin Wade; Lim, Robert W; Shukla, Shivendra D

2011-06-01

We have investigated whether Gcn5, a histone acetyltransferase (HAT), is involved in ethanol-induced acetylation of histone H3 at lysine 9 (H3AcK9) and has any effect on the gene expression. Human hepatoma HepG2 cells transfected with ethanol-metabolizing enzyme alcohol dehydrogenase 1 (VA 13 cells) were used. Knock down of Gcn5 by siRNA silencing decreased mRNA and protein levels of general control nondepressible 5 (GCN5), HAT activity, and also attenuated ethanol-induced H3AcK9 in VA13 cells. Illumina gene microarray analysis using total RNA showed 940 transcripts affected by GCN5 silencing or ethanol. Silencing caused differential expression of 891 transcripts (≥1.5-fold upregulated or downregulated). Among these, 492 transcripts were upregulated and 399 were downregulated compared with their respective controls. Using a more stringent threshold (≥2.5-fold), the array data from GCN5-silenced samples showed 57 genes differentially expressed (39 upregulated and 18 downregulated). Likewise, ethanol caused differential regulation of 57 transcripts with ≥1.5-fold change (35 gene upregulated and 22 downregulated). Further analysis showed that eight genes were differentially regulated that were common for both ethanol treatment and GCN5 silencing. Among these, SLC44A2 (a putative choline transporter) was strikingly upregulated by ethanol (three fold), and GCN5 silencing downregulated it (1.5-fold). The quantitative real-time polymerase chain reaction profile corroborated the array findings. This report demonstrates for the first time that (1) GCN5 differentially affects expression of multiple genes, (2) ethanol-induced histone H3-lysine 9 acetylation is mediated via GCN5, and (3) GCN5 is involved in ethanol-induced expression of the putative choline transporter SLC44A2. Copyright © 2011 Elsevier Inc. All rights reserved.

Enhanced Reactive Oxygen Species Production, Acidic Cytosolic pH and Upregulated Na+/H+ Exchanger (NHE) in Dicer Deficient CD4+ T Cells.

PubMed

Singh, Yogesh; Zhou, Yuetao; Zhang, Shaqiu; Abdelazeem, Khalid N M; Elvira, Bernat; Salker, Madhuri S; Lang, Florian

2017-01-01

MicroRNAs (miRNAs) negatively regulate gene expression at a post-transcriptional level. Dicer, a cytoplasmic RNase III enzyme, is required for the maturation of miRNAs from precursor miRNAs. Dicer, therefore, is a critical enzyme involved in the biogenesis and processing of miRNAs. Several biological processes are controlled by miRNAs, including the regulation of T cell development and function. T cells generate reactive oxygen species (ROS) with parallel H+ extrusion accomplished by the Na+/H+-exchanger 1 (NHE1). The present study explored whether ROS production, as well as NHE1 expression and function are sensitive to the lack of Dicer (miRNAs deficient) and could be modified by individual miRNAs. CD4+ T cells were isolated from CD4 specific Dicer deficient (DicerΔ/Δ) mice and the respective control mice (Dicerfl/fl). Transcript and protein levels were quantified with RT-PCR and Western blotting, respectively. For determination of intracellular pH (pHi) cells were incubated with the pH sensitive dye bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein (BCECF) and Na+/H+ exchanger (NHE) activity was calculated from re-alkalinization after an ammonium pulse. Changes in cell volume were measured using the forward scatter in flow cytometry, and ROS production utilizing 2',7' -dichlorofluorescin diacetate (DCFDA) fluorescence. Transfection of miRNA-control and mimics in T cells was performed using DharmaFECT3 reagent. ROS production, cytosolic H+ concentration, NHE1 transcript and protein levels, NHE activity, and cell volume were all significantly higher in CD4+ T cells from DicerΔ/Δ mice than in CD4+ T cells from Dicerfl/fl mice. Furthermore, individual miR-200b and miR-15b modify pHi and NHE activity in Dicerfl/fl and DicerΔ/Δ CD4+ T cells, respectively. Lack of Dicer leads to oxidative stress, cytosolic acidification, upregulated NHE1 expression and activity as well as swelling of CD4+ T cells, functions all reversed by miR-15b or miR-200b. © 2017 The Author

Histamine H4 receptor in oral lichen planus.

PubMed

Salem, A; Al-Samadi, A; Stegajev, V; Stark, H; Häyrinen-Immonen, R; Ainola, M; Hietanen, J; Konttinen, Y T

2015-04-01

Oral lichen planus (OLP) is an autoimmune disease characterized by a band-like T-cell infiltrate below the apoptotic epithelial cells and degenerated basement membrane. We tested the hypothesis that the high-affinity histamine H4 receptors (H4 Rs) are downregulated in OLP by high histamine concentrations and proinflammatory T-cell cytokines. Immunohistochemistry and immunofluorescence staining, image analysis and quantitative real-time polymerase chain reaction of tissue samples and cytokine-stimulated cultured SCC-25 and primary human oral keratinocytes. H4 R immunoreactivity was weak in OLP and characterized by mast cell (MC) hyperplasia and degranulation. In contrast to controls, H4 R immunostaining and MC counts were negatively correlated in OLP (P = 0.003). H4 R agonist at nanomolar levels led to a rapid internalization of H4 Rs, whereas high histamine concentration and interferon-γ decreased HRH4 -gene transcripts. Healthy oral epithelial cells are equipped with H4 R, which displays a uniform staining pattern in a MC-independent fashion. In contrast, in OLP, increased numbers of activated MCs associate with increasing loss of epithelial H4 R. Cell culture experiments suggest a rapid H4 R stimulation-dependent receptor internalization and a slow cytokine-driven decrease in H4 R synthesis. H4 R may be involved in the maintenance of healthy oral mucosa. In OLP, this maintenance might be impaired by MC degranulation and inflammatory cytokines. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Novel 1,5-diphenyl-6-substituted 1H-pyrazolo[3,4-d]pyrimidin-4(5H)-ones induced apoptosis in RKO colon cancer cells.

PubMed

Malki, Ahmed; Ashour, Hayam M A; Elbayaa, Rasha Y; Issa, Doaa A E; Aziz, Hassan A; Chen, Xiaozhuo

2016-12-01

Novel 1,5-diphenyl-6-substituted-1H-pyrazolo[3,4-d]pyrimidin-4(5H)-ones were synthesized and characterized. All compounds were screened for their anti-proliferative activities in five different cancer cell lines. The results showed that compounds 7a and 7b comprising aminoguanidino or guanidino moiety at position 6 inhibited proliferation of RKO colon cancer cells with IC50 of 8 and 4 μM, respectively. Compounds 7a and 7b induced apoptosis in RKO cells, which was confirmed by TUNEL and annexin V-FITC assays. Flow cytometric analysis indicated that compounds 7a and 7b arrested RKO cells in the G1 phase and the most active compound 7b increased levels of p53, p21, Bax, ERK1/2 and reduced levels of Bcl2 and Akt. Compound 7b also activates release of cytochrome c, which is consistent with activation of caspase-9. Additionally, compound 7b increased caspase-3 activity and cleaved PARP-1 in RKO cells. Collectively, these findings could establish a molecular basis for the development of new anti-cancer agents.

Anti-proliferative and pro-apoptotic effect of Smilax glabra Roxb. extract on hepatoma cell lines.

PubMed

Sa, Fei; Gao, Jian-Li; Fung, Kwok-Pui; Zheng, Ying; Lee, Simon Ming-Yuen; Wang, Yi-Tao

2008-01-10

Smilax glabra Roxb. (SGR) is the root of a traditional Chinese herb, referred to as tu fu ling in Chinese medicine. It is an inexpensive traditional Chinese medicine commonly used for the treatment of liver diseases, and a few studies have indicated that SGR has anti-hepatocarcinogenic and anti-cancer growth activities. In the current study, raw SGR plant was extracted with Accelerate Solvent Extractor, and the molecular mechanism by which S. glabra Roxb. extract (SGRE) has an anti-proliferative effect on the human hepatoma cell lines, HepG2 and Hep3B, was determined. We showed that SGRE inhibited HepG2 and Hep3B cell growth by causing cell-cycle arrest at either S phase or S/G2 transition and induced apoptosis, as evidenced by a DNA fragmentation assay. SGRE-induced apoptosis by alternation of mitochondrial transmembrane depolarization, release of mitochondrial cytochrome c, activation of caspase-3, and cleavage of poly(ADP-ribose) polymerase. The SGRE-mediated mitochondria-caspase dependent apoptotic pathway also involved activation of p38, JNK, and ERK mitogen-activated protein kinase signaling. Isometric compounds of astilbin (flavonoids) and smilagenin (saponin) have been identified as the main chemical constituents in SGRE by HPLC-MS/MS. These results have identified, for the first time, the biological activity of SGRE in HepG2 and Hep3B cells and should lead to further development of SGR for liver disease therapy.

High levels of E4-PHA-reactive oligosaccharides: potential as marker for cells with characteristics of hepatic progenitor cells.

PubMed

Sasaki, Nozomi; Moriwaki, Kenta; Uozumi, Naofumi; Noda, Katsuhisa; Taniguchi, Naoyuki; Kameyama, Akihiko; Narimatsu, Hisashi; Takeishi, Shunsaku; Yamada, Masao; Koyama, Nobuto; Miyoshi, Eiji

2009-12-01

Oligosaccharides serve as markers of the cell surface and have been used as certain kinds of tumor markers. In the present study, we established a simple method for isolating hepatic progenitor cells using a lectin, which recognizes a characteristic oligosaccharide structure. Rat liver epithelial (RLE) cells, which have been established as a hepatic stem-like cell, were used to identify characteristic oligosaccharide structures on hepatic stem cells. As a result from lectin micro array, several types of lectin including E4-PHA were identified to bind RLE cells specifically. Furthermore, lectin blot and lectin flow cytometry analyses showed that binding to E(4)-PHA lectin was significantly increased in RLE cells, compared to hepatocytes, and hepatoma cells. The induction of differentiation into a hepatocyte lineage of RLE cells by treatment with Oncostatin M and dexamethasone resulted in a decrease in E(4)-PHA binding. Using an E(4)-PHA column, we succeeded in isolating hepatic stem cells from LEC (Long-Evans with cinnamon coat color) rat livers with fluminant hepatitis. The characteristics of the established cells were similar to RLE cells and had a potential of proliferating in rat liver. These results suggest that oligosaccharides can serve as a novel marker for the isolation of the hepatic progenitor cells.

Metformin selectively targets redox control of complex I energy transduction.

PubMed

Cameron, Amy R; Logie, Lisa; Patel, Kashyap; Erhardt, Stefan; Bacon, Sandra; Middleton, Paul; Harthill, Jean; Forteath, Calum; Coats, Josh T; Kerr, Calum; Curry, Heather; Stewart, Derek; Sakamoto, Kei; Repiščák, Peter; Paterson, Martin J; Hassinen, Ilmo; McDougall, Gordon; Rena, Graham

2018-04-01

Many guanide-containing drugs are antihyperglycaemic but most exhibit toxicity, to the extent that only the biguanide metformin has enjoyed sustained clinical use. Here, we have isolated unique mitochondrial redox control properties of metformin that are likely to account for this difference. In primary hepatocytes and H4IIE hepatoma cells we found that antihyperglycaemic diguanides DG5-DG10 and the biguanide phenformin were up to 1000-fold more potent than metformin on cell signalling responses, gluconeogenic promoter expression and hepatocyte glucose production. Each drug inhibited cellular oxygen consumption similarly but there were marked differences in other respects. All diguanides and phenformin but not metformin inhibited NADH oxidation in submitochondrial particles, indicative of complex I inhibition, which also corresponded closely with dehydrogenase activity in living cells measured by WST-1. Consistent with these findings, in isolated mitochondria, DG8 but not metformin caused the NADH/NAD + couple to become more reduced over time and mitochondrial deterioration ensued, suggesting direct inhibition of complex I and mitochondrial toxicity of DG8. In contrast, metformin exerted a selective oxidation of the mitochondrial NADH/NAD + couple, without triggering mitochondrial deterioration. Together, our results suggest that metformin suppresses energy transduction by selectively inducing a state in complex I where redox and proton transfer domains are no longer efficiently coupled. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

DJ-1/Park7 Sensitive Na+ /H+ Exchanger 1 (NHE1) in CD4+ T Cells.

PubMed

Zhou, Yuetao; Shi, Xiaolong; Chen, Hong; Zhang, Shaqiu; Salker, Madhuri S; Mack, Andreas F; Föller, Michael; Mak, Tak W; Singh, Yogesh; Lang, Florian

2017-11-01

DJ-1/Park7 is a redox-sensitive chaperone protein counteracting oxidation and presumably contributing to the control of oxidative stress responses and thus inflammation. DJ-1 gene deletion exacerbates the progression of Parkinson's disease presumably by augmenting oxidative stress. Formation of reactive oxygen species (ROS) is paralleled by activation of the Na + /H + exchanger 1 (NHE1). ROS formation in CD4 + T cells plays a decisive role in regulating inflammatory responses. In the present study, we explored whether DJ-1 is expressed in CD4 + T cells, and affects ROS production as well as NHE1 in those cells. To this end, DJ-1 and NHE1 transcript, and protein levels were quantified by qRT-PCR and Western blotting, respectively, intracellular pH (pH i ) utilizing bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein (BCECF) fluorescence, NHE activity from realkalinization after an ammonium pulse, and ROS production utilizing 2',7' -dichlorofluorescin diacetate (DCFDA) fluorescence. As a result DJ-1 was expressed in CD4 + T cells. ROS formation, NHE1 transcript levels, NHE1 protein, and NHE activity were higher in CD4 + T cells from DJ-1 deficient mice than in CD4 + T cells from wild type mice. Antioxidant N-acetyl-cysteine (NAC) and protein tyrosine kinase (PTK) inhibitor staurosporine decreased the NHE activity in DJ-1 deficient CD4 + T cells, and blunted the difference between DJ-1 -/- and DJ-1 +/+ CD4 + T cells, an observation pointing to a role of ROS in the up-regulation of NHE1 in DJ-1 -/- CD4 + T cells. In conclusion, DJ-1 is a powerful regulator of ROS production as well as NHE1 expression and activity in CD4 + T cells. J. Cell. Physiol. 232: 3050-3059, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Expression of Interferon Lambda 4 Is Associated with Reduced Proliferation and Increased Cell Death in Human Hepatic Cells

PubMed Central

Onabajo, Olusegun O.; Porter-Gill, Patricia; Paquin, Ashley; Rao, Nina; Liu, Luyang; Tang, Wei; Brand, Nathan

2015-01-01

Interferon lambda 4 (IFN-λ4) is a novel type-III interferon that can be generated only in individuals carrying a ΔG frame-shift allele of an exonic genetic variant (rs368234815-ΔG/TT). The rs368234815-ΔG allele is strongly associated with decreased clearance of hepatitis C virus (HCV) infection. Here, we further explored the biological function of IFN-λ4 expressed in human hepatic cells—a hepatoma cell line HepG2 and fresh primary human hepatocytes (PHHs). We performed live confocal imaging, cell death and proliferation assays, mRNA expression profiling, protein detection, and antibody blocking assays using transient and inducible stable in vitro systems. Not only did we observe significant intracellular retention of IFN-λ4 but also detected secreted IFN-λ4 in the culture media of expressing cells. Secreted IFN-λ4 induced strong activation of the interferon-stimulated genes (ISGs) in IFN-λ4-expressing and surrounding cells in transwell assays. Specifically, in PHHs, secreted IFN-λ4 induced expression of the CXCL10 transcript and a corresponding pro-inflammatory chemokine, IP-10. In IFN-λ4-expressing HepG2 cells, we also observed decreased proliferation and increased cell death. All IFN-λ4-induced phenotypes—activation of ISGs, decreased proliferation, and increased cell death—could be inhibited by an anti-IFN-λ4-specific antibody. Our study offers new insights into biology of IFN-λ4 and its possible role in HCV clearance. PMID:26134097

Silica-induced initiation of circular ZC3H4 RNA/ZC3H4 pathway promotes the pulmonary macrophage activation.

PubMed

Yang, Xiyue; Wang, Jing; Zhou, Zewei; Jiang, Rong; Huang, Jie; Chen, Lulu; Cao, Zhouli; Chu, Han; Han, Bing; Cheng, Yusi; Chao, Jie

2018-06-01

Phagocytosis of silicon dioxide (SiO 2 ) into lung cells causes an inflammatory cascade that results in fibroblast proliferation and migration, followed by fibrosis. Circular RNAs (circRNAs) are a subclass of noncoding RNAs that are present within mammalian cells; however, researchers have not determined whether circRNAs are involved in the pathophysiologic process of silicosis. To elucidate the role of these RNAs in SiO 2 -induced inflammation in pulmonary macrophages, we investigated the upstream molecular mechanisms and functional effects of circRNAs on cell apoptosis, proliferation, and migration. Primary cultures of alveolar macrophages from healthy donors and from patients and the RAW264.7 macrophage cell line were used to explore the functions of circZC3H4 RNA in macrophage activation. The experimental results indicated the following: 1) SiO 2 concomitantly increased circZC3H4 RNA expression and increased ZC3H4 protein levels; 2) circular ZC3H4 (circZC3H4) RNA and ZC3H4 protein participated in SiO 2 -induced macrophage activation; and 3) SiO 2 -activated macrophages promoted fibroblast proliferation and migration via the circZC3H4 RNA/ZC3H4 pathway. The up-regulation of the ZC3H4 protein was confirmed in tissue samples from patients with silicosis. Our study elucidates a link between SiO 2 -induced macrophage activation and the circZC3H4 RNA/ZC3H4 pathway, thereby providing novel insight into the potential use of ZC3H4 to develop novel therapeutic strategies for silicosis.-Yang, X., Wang, J., Zhou, Z., Jiang, R., Huang, J., Chen, L., Cao, Z., Chu, H., Han, B., Cheng, Y., Chao, J. Silica-induced initiation of circular ZC3H4 RNA/ZC3H4 pathway promotes the pulmonary macrophage activation.

Low external pH replaces 2,4-D in maintaining and multiplying 2,4-D-initiated embryogenic cells of carrot

NASA Technical Reports Server (NTRS)

Smith, D. L.; Krikorian, A. D.

1990-01-01

A mixed culture comprised of both embryonic globules and nonembryogenic callus was derived from seedling hypocotyls of Daucus carota cv. Scarlet Nantes on 2,4-D- containing medium using well-established methods. Then the mixed cultures were transferred to, and serially subcultured on, a hormone-free medium near pH 4. The medium contained 1 mM NH4+ as the sole nitrogen source. When cultured in this way, embryonic globules were able to multiply without development into later embryo stages. Nonembryogenic callus did not survive. Continuous culture of embryonic globules on this low pH hormone-free medium yielded cultures consisting entirely of preglobular stage proembryos (PGSPs). PGSP cultures have been maintained as such with continuous multiplication for nearly 2 years without loss of embryogenic potential. These hormone-free-maintained PGSPs continue their development to later embryo stages when cultured on the same hormone-free medium buffered at pH 5.8. We show that hormone-free medium near pH 4 can replace 2,4-D in its ability to sustain multiplication of 2,4-D-initiated embryogenic cells of carrot at an acceptable growth rate without their development into later embryo stages. This procedure provides selective conditions that do not permit the growth of non-embryogenic cells while providing an adequate environment for embryogenic cell proliferation and should prove invaluable in studying habituation.

Creating, Storing, and Dumping Low and High Resolution Graphics on the Apple IIe Microcomputer System.

ERIC Educational Resources Information Center

Fletcher, Richard K., Jr.

This description of procedures for dumping high and low resolution graphics using the Apple IIe microcomputer system focuses on two special hardware configurations that are commonly used in schools--the Apple Dot Matrix Printer with the Apple Parallel Interface Card, and the Imagewriter Printer with the Apple Super Serial Interface Card. Special…

Diesel Exhaust Particles Enhance MUC4 Expression in NCI-H292 Cells and Nasal Epithelial Cells via the p38/CREB Pathway.

PubMed

Park, Il-Ho; Kang, Ju-Hyung; Kim, Jin Ah; Shin, Jae-Min; Lee, Heung-Man

2016-01-01

Diesel exhaust particles (DEPs), the major contributors to air pollution, induce inflammatory responses in the nasal epithelium. Overproduction of airway mucins is an important pathogenic finding in inflammatory airway diseases. The aims of the present study were to determine the effect of DEPs on the expression of the mucin gene MUC4 and to investigate the underlying mechanism of DEP-induced MUC4 expression in NCI-H292 cells and primary nasal epithelial cells (PNECs). NCI-H292 cells were stimulated for 24 h with DEPs. Messenger RNA (mRNA) and protein expression of MUC4 was determined by real-time reverse transcription (RT) polymerase chain reaction (PCR) and Western blotting. NCI-H292 cells were exposed to 3 mitogen-activated protein kinase inhibitors (U0126, SB203580, and SP600125) and a CREB (cAMP response element-binding protein) inhibitor prior to stimulation with DEPs, and MUC4 expression was examined by RT-PCR and Western blotting. PNECs were pretreated with a p38 inhibitor and CREB inhibitor prior to stimulation with DEPs, and MUC4 expression was then determined by RT-PCR and/or Western blotting. DEPs significantly increased the expression of MUC4 mRNA and protein. MUC4 mRNA and protein expression was inhibited by pretreatment with p38 and CREB inhibitors in NCI-H292 stimulated with DEPs. p38 and CREB inhibitors also blocked the expression of MUC4 mRNA and protein in DEP-stimulated PNECs. We demonstrated that DEPs stimulated the expression of MUC4 via the p38/CREB pathway in NCI-H292 cells and PNECs. The results of the present study pave the way for further studies on the role of MUC4 in DEP-induced hypersecretion in airway epithelium. © 2017 S. Karger AG, Basel.

Smad4 mediated BMP2 signal is essential for the regulation of GATA4 and Nkx2.5 by affecting the histone H3 acetylation in H9c2 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Si, Lina; Shi, Jin; Gao, Wenqun

2014-07-18

Highlights: • BMP2 can upregulated cardiac related gene GATA4, Nkx2.5, MEF2c and Tbx5. • Inhibition of Smad4 decreased BMP2-induced hyperacetylation of histone H3. • Inhibition of Smad4 diminished BMP2-induced overexpression of GATA4 and Nkx2.5. • Inhibition of Smad4 decreased hyperacetylated H3 in the promoter of GATA4 and Nkx2.5. • Smad4 is essential for BMP2 induced hyperacetylated histone H3. - Abstract: BMP2 signaling pathway plays critical roles during heart development, Smad4 encodes the only common Smad protein in mammals, which is a pivotal nuclear mediator. Our previous studies showed that BMP2 enhanced the expression of cardiac transcription factors in part bymore » increasing histone H3 acetylation. In the present study, we tested the hypothesis that Smad4 mediated BMP2 signaling pathway is essential for the expression of cardiac core transcription factors by affecting the histone H3 acetylation. We successfully constructed a lentivirus-mediated short hairpin RNA interference vector targeting Smad4 (Lv-Smad4) in rat H9c2 embryonic cardiac myocytes (H9c2 cells) and demonstrated that it suppressed the expression of the Smad4 gene. Cultured H9c2 cells were transfected with recombinant adenoviruses expressing human BMP2 (AdBMP2) with or without Lv-Smad4. Quantitative real-time RT-PCR analysis showed that knocking down of Smad4 substantially inhibited both AdBMP2-induced and basal expression levels of cardiac transcription factors GATA4 and Nkx2.5, but not MEF2c and Tbx5. Similarly, chromatin immunoprecipitation (ChIP) analysis showed that knocking down of Smad4 inhibited both AdBMP2-induced and basal histone H3 acetylation levels in the promoter regions of GATA4 and Nkx2.5, but not of Tbx5 and MEF2c. In addition, Lv-Smad4 selectively suppressed AdBMP2-induced expression of HAT p300, but not of HAT GCN5 in H9c2 cells. The data indicated that inhibition of Smad4 diminished both AdBMP2 induced and basal histone acetylation levels in the promoter

A dimeric urea of the bisabolene sesquiterpene from the Okinawan marine sponge Axinyssa sp. inhibits protein tyrosine phosphatase 1B activity in Huh-7 human hepatoma cells.

PubMed

Abdjul, Delfly B; Kanno, Syu-Ichi; Yamazaki, Hiroyuki; Ukai, Kazuyo; Namikoshi, Michio

2016-01-15

Protein tyrosine phosphatase 1B (PTP1B) plays an important role as a negative regulator of the insulin and leptin signaling pathways. Therefore, this enzyme is regarded as an attractive therapeutic target for the treatment of type 2 diabetes and obesity. Our screening program for PTP1B inhibitors led to the isolation of four sesquiterpenes and sterol: N,N'-bis[(6R,7S)-7-amino-7,8-dihydro-α-bisabolen-7-yl]urea (1), (6R,7S)-7-amino-7,8-dihydro-α-bisabolene (2), (1R,6S,7S,10S)-10-isothiocyanato-4-amorphene (3), axinisothiocyanate J (4), and axinysterol (5) from the marine sponge Axinyssa sp. collected at Iriomote Island. Of these, compound 1 was the most potent inhibitor of PTP1B activity (IC50=1.9μM) without cytotoxicity at 50μM in two human cancer cell lines, hepatoma Huh-7 and bladder carcinoma EJ-1 cells. Compound 1 also moderately enhanced the insulin-stimulated phosphorylation levels of Akt in Huh-7 cells. Therefore, compound 1 has potential as a new type of anti-diabetic drug candidate possessing PTP1B inhibitory activity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Modifications in plasma membrane lipid composition and morphological features of AH-130 hepatoma cells by polyenylphosphatidylcholine in vivo treatment.

PubMed

Cinosi, Vincenzo; Antonini, Roberto; Crateri, Pasqualina; Arancia, Giuseppe

2011-07-01

The plasma membrane lipid composition in AH-130 hepatoma cells was found to change remarkably after polyenylphosphatidylcholine (PPC) treatment. Plasma membranes from cells grown in rats treated for 7 days i.v. with 20 mg/kg/day PPC, when compared to those of control cells, did not show significantly different amounts of cholesterol or phospholipids relative to protein content, but, surprisingly, the individual phospholipid distribution inside the two membrane leaflets changed dramatically. Phosphatidylcholine (PC), the major phospholipid in the external membrane leaflet, increased ~47% (p<0.001). By contrast, phosphatidylethanolamine (PE), the most important component of the inner leaflet, decreased nearly 37% (p<0.001), while sphingomyelin (SM) also decreased ~17%, (p=0.1). Tumor cells collected from control rats at the same time interval and observed by scanning electron microscopy, exhibited a spherical shape with numerous and randomly distributed long microvilli, the same morphological and ultrastructural features displayed by the implanted cells. Conversely, tumor cells from PPC-treated rats no longer showed the roundish cell profile, and microvilli appeared shortened and enlarged, with the formation of surface blebs. Transmission electron microscopy observations confirmed the morphological and ultrastructural cell changes, mainly seen as loss of microvilli and intense cytoplasmic vacuolization. Taken together, these results indicate that the new phospholipid class distribution in the plasma membrane leaflets, modifying tumor cell viable structures, produced heavy cell damage and in many cases brought about complete cellular disintegration.

Silicate Inclusions in the Kodaikanal IIE Iron Meteorite

NASA Technical Reports Server (NTRS)

Kurat, G.; Varela, M. E.; Zinner, E.

2005-01-01

Silicate inclusions in iron meteorites display an astonishing chemical and mineralogical variety, ranging from chondritic to highly fractionated, silica- and alkali-rich assemblages. In spite of this, their origin is commonly considered to be a simple one: mixing of silicates, fractionated or unfractionated, with metal. The latter had to be liquid in order to accommodate the former in a pore-free way which all models accomplish by assuming shock melting. II-E iron meteorites are particularly interesting because they contain an exotic zoo of silicate inclusions, including some chemically strongly fractionated ones. They also pose a formidable conundrum: young silicates are enclosed by very old metal. This and many other incompatibilities between models and reality forced the formulation of an alternative genetic model for irons. Here we present preliminary findings in our study of Kodaikanal silicate inclusions.

Ara h 1 CD4+ T cell epitope-based peptides: candidates for a peanut allergy therapeutic.

PubMed

Prickett, S R; Voskamp, A L; Phan, T; Dacumos-Hill, A; Mannering, S I; Rolland, J M; O'Hehir, R E

2013-06-01

Peanut allergy is a life-threatening condition; there is currently no cure. While whole allergen extracts are used for specific immunotherapy for many allergies, they can cause severe reactions and even fatalities in peanut allergy. To identify short, HLA-degenerate CD4(+) T cell epitope-based peptides of the major peanut allergen Ara h 1 that target allergen-specific T cells without causing IgE-mediated inflammatory cell activation, as candidates for safe peanut-specific immunotherapy. Ara h 1-specific CD4(+) T cell lines (TCL) were generated from peripheral blood mononuclear cells (PBMC) of peanut-allergic subjects using CFSE-based methodology. T cell epitopes were identified using CFSE and thymidine-based proliferation assays. Epitope HLA-restriction was investigated using blocking antibodies, HLA-genotyping and epitope prediction algorithms. Functional peanut-specific IgE reactivity to peptides was assessed by basophil activation assay. A total of 145 Ara h 1-specific TCL were generated from 18 HLA-diverse peanut-allergic subjects. The TCL recognized 20-mer peptides throughout Ara h 1. Nine 20-mers containing the most frequently recognized epitopes were selected and their recognition confirmed in 18 additional peanut-allergic subjects. Ten core epitopes were mapped within these 20-mers. These were HLA-DQ and/or HLA-DR restricted, with each presented on at least two different HLA-molecules. Seven short (≤ 20 aa) non-basophil-reactive peptides encompassing all core epitopes were designed and validated in peanut-allergic donor PBMC T cell assays. Short CD4(+) T cell epitope-based Ara h 1 peptides were identified as novel candidates for a safe, T cell targeted peanut-specific immunotherapy for HLA-diverse populations. © 2013 John Wiley & Sons Ltd.

High content image analysis for human H4 neuroglioma cells exposed to CuO nanoparticles.

PubMed

Li, Fuhai; Zhou, Xiaobo; Zhu, Jinmin; Ma, Jinwen; Huang, Xudong; Wong, Stephen T C

2007-10-09

High content screening (HCS)-based image analysis is becoming an important and widely used research tool. Capitalizing this technology, ample cellular information can be extracted from the high content cellular images. In this study, an automated, reliable and quantitative cellular image analysis system developed in house has been employed to quantify the toxic responses of human H4 neuroglioma cells exposed to metal oxide nanoparticles. This system has been proved to be an essential tool in our study. The cellular images of H4 neuroglioma cells exposed to different concentrations of CuO nanoparticles were sampled using IN Cell Analyzer 1000. A fully automated cellular image analysis system has been developed to perform the image analysis for cell viability. A multiple adaptive thresholding method was used to classify the pixels of the nuclei image into three classes: bright nuclei, dark nuclei, and background. During the development of our image analysis methodology, we have achieved the followings: (1) The Gaussian filtering with proper scale has been applied to the cellular images for generation of a local intensity maximum inside each nucleus; (2) a novel local intensity maxima detection method based on the gradient vector field has been established; and (3) a statistical model based splitting method was proposed to overcome the under segmentation problem. Computational results indicate that 95.9% nuclei can be detected and segmented correctly by the proposed image analysis system. The proposed automated image analysis system can effectively segment the images of human H4 neuroglioma cells exposed to CuO nanoparticles. The computational results confirmed our biological finding that human H4 neuroglioma cells had a dose-dependent toxic response to the insult of CuO nanoparticles.

Demonstration of a 4H SiC betavoltaic cell

NASA Astrophysics Data System (ADS)

Chandrashekhar, M. V. S.; Thomas, Christopher I.; Li, Hui; Spencer, M. G.; Lal, Amit

2006-01-01

A betavoltaic cell in 4H SiC is demonstrated. A p-n diode structure was used to collect the charge from a 1mCi Ni-63 source. An open circuit voltage of 0.72V and a short circuit current density of 16.8nA /cm2 were measured in a single p-n junction. A 6% lower bound on the power conversion efficiency was obtained. A simple photovoltaic-type model was used to explain the results. Fill factor and backscattering effects were included in the efficiency calculation. The performance of the device was limited by edge recombination.

Memantine Can Reduce Ethanol-Induced Caspase-3 Activity and Apoptosis in H4 Cells by Decreasing Intracellular Calcium.

PubMed

Wang, Xiaolong; Chen, Jiajun; Wang, Hongbo; Yu, Hao; Wang, Changliang; You, Jiabin; Wang, Pengfei; Feng, Chunmei; Xu, Guohui; Wu, Xu; Zhao, Rui; Zhang, Guohua

2017-08-01

Caspase-3 activation and apoptosis are associated with various neurodegenerative disorders. Calcium activation is an important factor in promoting apoptosis. We, therefore, assessed the role of intracellular calcium in ethanol-induced activation of caspase-3 in H4 human neuroglioma cells and the protective effect of the NMDA receptor antagonist, memantine, on ethanol-induced apoptosis in H4 cells. H4 cells were treated with 100 mM EtOH (in culture medium) for 2 days. For interaction studies, cells were treated with memantine (4 μM), EDTA (1 mM), or BAPTA-AM (10 μM) before treatment with EtOH. Knockdown of the gene encoding the NR1 subunit of the NMDA receptor was performed using RNAi. Apoptosis was detected by Annexin V-FITC/PI staining and flow cytometry. Cell viability was detected using an MTS cell proliferation kit. Fluorescence dual wavelength spectrophotometry was used to determine the intracellular calcium concentration. The levels of NR1, caspase-3, IP3R1, and SERCA1 proteins were detected by western blotting. NR1, IP3R1, and SERCA1 mRNA levels were detected by qPCR. We observed increased expression of NR1, IP3R1, SERCA1, and increased intracellular levels of calcium ions in H4 cells exposed to ethanol. In addition, the calcium chelators, EDTA and BAPTA, and RNAi disruption of the NMDA receptor reduced ethanol-induced caspase-3 activation in H4 cells. Memantine treatment reduced the ethanol-induced increase of intracellular calcium, caspase-3 activation, apoptosis, and the ethanol-induced decrease in cell viability. Our results indicate that ethanol-induced caspase-3 activation and apoptosis are likely to be dependent on cytosolic calcium levels and that they can be reduced by memantine treatment.

Comparison of DNA damage in human-derived hepatoma line (HepG2) exposed to the fifteen drinking water disinfection byproducts using the single cell gel electrophoresis assay.

PubMed

Zhang, Li; Xu, Liang; Zeng, Qiang; Zhang, Shao-Hui; Xie, Hong; Liu, Ai-Lin; Lu, Wen-Qing

2012-01-24

Disinfection of drinking water reduces pathogenic infection, but generates disinfection by-products (DBPs) in drinking water. In this study, the effect of fifteen DBPs on DNA damage in human-derived hepatoma line (HepG2) was investigated by the single cell gel electrophoresis (SCGE) assay. These fifteen DBPs are: four trihalomethanes (THMs), six haloacetic acides (HAAs), three haloacetonitriles (HANs), 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), and chloral hydrate (CH). Based on the minimal effective concentration (MEC) at which DBPs induced significant increase in olive tail moment (OTM), the rank order of DNA-damaging potency is: bromodichloromethane (BDCM)>dibromochloromethane (DBCM)>tribromomethane (TBM)>trichloromethane (TCM) of the four THMs; iodoacetic acid (IA)>bromoacetic acid (BA)>dibromoacetic acid (DBA)>dichloracetic acid (DCA)>trichloroacetic acid (TCA) of the five HAAs; dibromoacetonitrile (DBN)approximately dichloroacetonitrile (DCN)>trichloroacetonitrile (TCN) of the three HANs. The DNA damaging potency of MX and CH is similar to TCA and DCA, respectively. IA is the most genotoxic DBP in the fifteen DBPs, followed by BA. Chloroacetic acid (CA) is not genotoxic in this assay. Our findings indicated that HepG2/SCGE is a sensitive tool to evaluate the genotoxicity of DBPs and iodinated DBPs are more genotoxic than brominated DBPs, but chlorinated DBPs are less genotoxic than brominated DBPs. © 2011 Elsevier B.V. All rights reserved.

Epithelial-mesenchymal transition leads to crizotinib resistance in H2228 lung cancer cells with EML4-ALK translocation.

PubMed

Kim, Hyeong Ryul; Kim, Woo Sung; Choi, Yun Jung; Choi, Chang Min; Rho, Jin Kyung; Lee, Jae Cheol

2013-12-01

Epithelial-mesenchymal transition (EMT) is associated with reduced sensitivity to many chemotherapeutic drugs, including EGFR tyrosine kinase inhibitors. Here, we investigated if this reduced sensitivity also contributes to resistance to crizotinib, an ALK inhibitor of lung cancer that exhibits the EML4-ALK translocation. We established a crizotinib-resistant subline (H2228/CR), which was derived from the parental H2228 cell line by long-term exposure to increasing concentrations of crizotinib. Characteristics associated with EMT, including morphology, EMT marker proteins, and cellular mobility, were analyzed. Compared with H2228 cells, the growth of H2228/CR cells was independent of EML4-ALK, and H2228/CR cells showed cross-resistance to TAE-684 (a second-generation ALK inhibitor). Phenotypic changes to the spindle-cell shape were noted in H2228/CR cells, which were accompanied by a decrease in E-cadherin and increase in vimentin and AXL. In addition, H2228/CR cells showed increased secretion and expression of TGF-β1. Invasion and migration capabilities were dramatically increased in H2228/CR cells. Applying TGF-β1 treatment to parental H2228 cells for 72 h induced reversible EMT, leading to crizotinib resistance, but this was reversed by the removal of TGF-β1. Suppression of vimentin in H2228/CR cells by siRNA treatment restored sensitivity to crizotinib. Furthermore, these resistant cells remained highly sensitive to the Hsp90 inhibitors, similar to the parental H2228 cells. In conclusion, we suggest EMT is possibly involved in acquired resistance to crizotinib, and that HSP90 inhibitors could be a promising option for the treatment of EMT. Copyright © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Direct N2H4/H2O2 Fuel Cells Powered by Nanoporous Gold Leaves

PubMed Central

Yan, Xiuling; Meng, Fanhui; Xie, Yun; Liu, Jianguo; Ding, Yi

2012-01-01

Dealloyed nanoporous gold leaves (NPGLs) are found to exhibit high electrocatalytic properties toward both hydrazine (N2H4) oxidation and hydrogen peroxide (H2O2) reduction. This observation allows the implementation of a direct hydrazine-hydrogen peroxide fuel cell (DHHPFC) based on these novel porous membrane catalysts. The effects of fuel and oxidizer flow rate, concentration and cell temperature on the performance of DHHPFC are systematically investigated. With a loading of ~0.1 mg cm−2 Au on each side, an open circuit voltage (OCV) of 1.2 V is obtained at 80°C with a maximum power density 195 mW cm−2, which is 22 times higher than that of commercial Pt/C electrocatalyst at the same noble metal loading. NPGLs thus hold great potential as effective and stable electrocatalysts for DHHPFCs. PMID:23230507

Effects of quercetin on CDK4 mRNA and protein expression in A549 cells infected by H1N1

PubMed Central

WAN, QIAOFENG; WANG, HAO; LIN, YUAN; GU, LIGANG; HAN, MEI; YANG, ZHIWEI; ZHANG, YANLI; MA, RUI; WANG, LI; WANG, ZHISHENG

2013-01-01

This study was conducted to investigate the effects of quercetin on the expression of cyclin-dependent kinase (CDK4) mRNA and protein in A549 lung epithelial tumor cells infected by H1N1. First, the Thiazolyl Blue Tetrazolium Bromide (MTT) method was used to determine H1N1 virulence, quercetin cytotoxicity and inhibition of the cytopathic effect of H1N1 on A549 cells by quercetin. Subsequently, 100 TCID50 H1N1 was used to infect A549 cells for 2 h prior to culture in maintenance media containing 10 mg/l quercetin. After 4, 12, 24 and 48 h of culture, the cells were collected and total RNA and protein were extracted. Fluorescent quantitative polymerase chain reaction and western blot analysis were then performed to assess the expression of CDK4 mRNA and protein. The experiment demonstrated that the TCID50 of H1N1 in A549 cells was 10−4.75, the maximum non-toxic concentration of quercetin in A549 cells was 30–60 mg/l and the minimum effective concentration of quercetin for the inhibition of the H1N1 cytopathic effect on A549 cells was 10 mg/l. The results indicated that quercetin may significantly inhibit CDK4 mRNA and protein overexpression caused by H1N1 within 4–48 h. In conclusion, quercetin may protect against H1N1 infection by effectively reducing the mRNA and protein expression of CDK4 caused by H1N1 infection. PMID:24649026

Genotoxic activity and induction of biotransformation enzymes in two human cell lines after treatment by Erika fuel extract.

PubMed

Amat-Bronnert, Agnès; Castegnaro, Marcel; Pfohl-Leszkowicz, Annie

2007-01-01

On 12 December 1999, the tanker Erika broke in two parts at about 60km from the Brittany French coasts (Point of Penmarc'h, Sud Finistère, France). About 10,000tonnes of heavy oil fuel were released in the sea. DNA adduct have been detected in fish liver and mussels digestive gland exposed to the Erika oil spill. In order to investigate the mechanism by which Erika fuel extract exhibits genotoxic effects the induction of DNA adducts by an Erika fuel extract have been analysed on two cell lines, human epithelial bronchial cells (WI) and human hepatoma cells. DNA adducts, reflected by a diagonal radioactive zone and individual adducts are detected only in hepatoma cells indicating biotransformation via CYP 1A2 and CYP 1B1. In addition, Erika fuel extract induces some metabolizing enzymes such CYP 1A2, COX2 and 5-LOX, the two later are involved in cancer processes. Formation of leucotrienes B4 (LTB(4)), a mediator playing a role in inflammation, is induced in epithelial bronchial cells. Since inhalation is one of the ways of contamination for human, the above results are important for human health and prevention. Copyright © 2006 Elsevier B.V. All rights reserved.

A study on the thermochemotherapy effect of nanosized As2O3/MZF thermosensitive magnetoliposomes on experimental hepatoma in vitro and in vivo

NASA Astrophysics Data System (ADS)

Wang, Li; Zhang, Jia; An, Yanli; Wang, Ziyu; Liu, Jing; Li, Yutao; Zhang, Dongsheng

2011-08-01

In this paper, we describe the synthesis and characterization of a nanosized, thermosensitive magnetoliposome encapsulating magnetic nanoparticles (MZFs) and antitumor drugs (As2O3). The nanoliposomes were spherical and mostly single volume, with an average diameter of 128.2 nm. Differential scanning calorimetry (DSC) showed a liposome phase transition temperature of 42.71 °C. After that, we studied the liposomes' anti-hepatoma effect in vitro and in vivo. The antitumor effect of the nanoliposomes on human hepatoma cells, SMMC-7721, and changes in expression of apoptosis-related proteins were examined in vitro. The results show that As2O3/MZF thermosensitive magnetoliposomes combined with hyperthermia had a great impact on the Bax/Bcl-2 ratio, which increased to 1.914 and exhibited a rapid response to induce apoptosis of tumor cells. An in situ rabbit liver tumor model was established and used to evaluate the antitumor effect of combined hyperthermia and chemotherapy following transcatheter arterial embolization with As2O3/MZF thermosensitive magnetoliposomes. The results demonstrated a strong anti-hepatoma effect, with a tumor volume inhibition rate of up to 85.22%. Thus, As2O3/MZF thermosensitive magnetoliposomes may play a great role in the treatment of hepatocarcinoma.

A PXR reporter gene assay in a stable cell culture system: CYP3A4 and CYP2B6 induction by pesticides.

PubMed

Lemaire, Géraldine; de Sousa, Georges; Rahmani, Roger

2004-12-15

A stable hepatoma cell line expressing the human pregnane X receptor (hPXR) and the cytochrome P4503A4 (CYP3A4) distal and proximal promoters plus the luciferase reporter gene was developed to assess the ability of several xenobiotic agents to induce CYP3A4 and CYP2B6. After selection for neomycin resistance, one clone, displaying high luciferase activity in response to rifampicin (RIF), was isolated and the stable expression of hPXR was confirmed by reverse transcription polymerase chain reaction (RT-PCR). Dose-response curves were generated by treating these cells with increasing concentrations of RIF, phenobarbital (PB), clotrimazole (CLOT) or 5beta-pregnane-3,20-dione (5beta-PREGN). The effective concentrations for half maximal response (EC50) were determined for each of these compounds. RIF was the most effective compound, with maximal luciferase activity induced at 10 microM. The agonist activities of PXR-specific inducers measured using our stable model were consistent with those measured in transient transfectants. The abilities of organochlorine (OC), organophosphate (OP) and pyrethroid pesticides (PY) to activate hPXR were also assessed and found to be consistent with the abilities of these compounds to induce CYP3A4 and CYP2B6 in primary culture of human hepatocytes. These results suggest that CYP3A4 and CYP2B6 regulation through PXR activation by persistent pesticides may have an impact on the metabolism of xenobiotic agents and endogenous steroid hormones. Our model provides a useful tool for studying hPXR activation and for identifying agents capable of inducing CYP3A4 and CYP2B6.

Ara h 2 peptides containing dominant CD4+ T-cell epitopes: candidates for a peanut allergy therapeutic.

PubMed

Prickett, Sara R; Voskamp, Astrid L; Dacumos-Hill, April; Symons, Karen; Rolland, Jennifer M; O'Hehir, Robyn E

2011-03-01

Peanut allergy is a life-threatening condition; there is currently no cure. Although whole allergen extracts are used for specific immunotherapy for many allergies, they can cause severe reactions, and even fatalities, in peanut allergy. This study aimed to identify short, T-cell epitope-based peptides that target allergen-specific CD4(+) T cells but do not bind IgE as candidates for safe peanut-specific immunotherapy. Multiple CD4(+) T-cell lines specific for the major peanut allergen Ara h 2 were generated from PBMCs of 16 HLA-diverse subjects with peanut allergy by using 5,6-carboxyfluorescein diacetate succinimidylester-based methodology. Proliferation and ELISPOT assays were used to identify dominant epitopes recognized by T-cell lines and to confirm recognition by peripheral blood T cells of epitope-based peptides modified for therapeutic production. HLA restriction of core epitope recognition was investigated by using anti-HLA blocking antibodies and HLA genotyping. Serum-IgE peptide-binding was assessed by dot-blot. Five dominant CD4(+) T-cell epitopes were identified in Ara h 2. In combination, these were presented by HLA-DR, HLA-DP, and HLA-DQ molecules and recognized by T cells from all 16 subjects. Three short peptide variants containing these T-cell epitopes were designed with cysteine-to-serine substitutions to facilitate stability and therapeutic production. Variant peptides showed HLA-binding degeneracy, did not bind peanut-specific serum IgE, and could directly target T(H)2-type T cells in peripheral blood of subjects with allergy. Short CD4(+) T-cell epitope-based Ara h 2 peptides were identified as novel candidates for a T-cell-targeted peanut-specific immunotherapy for an HLA-diverse population. Copyright © 2010 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Magnetic nanoparticles for targeted therapeutic gene delivery and magnetic-inducing heating on hepatoma

NASA Astrophysics Data System (ADS)

Yuan, Chenyan; An, Yanli; Zhang, Jia; Li, Hongbo; Zhang, Hao; Wang, Ling; Zhang, Dongsheng

2014-08-01

Gene therapy holds great promise for treating cancers, but their clinical applications are being hampered due to uncontrolled gene delivery and expression. To develop a targeted, safe and efficient tumor therapy system, we constructed a tissue-specific suicide gene delivery system by using magnetic nanoparticles (MNPs) as carriers for the combination of gene therapy and hyperthermia on hepatoma. The suicide gene was hepatoma-targeted and hypoxia-enhanced, and the MNPs possessed the ability to elevate temperature to the effective range for tumor hyperthermia as imposed on an alternating magnetic field (AMF). The tumoricidal effects of targeted gene therapy associated with hyperthermia were evaluated in vitro and in vivo. The experiment demonstrated that hyperthermia combined with a targeted gene therapy system proffer an effective tool for tumor therapy with high selectivity and the synergistic effect of hepatoma suppression.

Potentiation of Tumor Necrosis Factor-α-induced Tumor Cell Apoptosis by a Small Molecule Inhibitor for Anti-apoptotic Protein hPEBP4

PubMed Central

Qiu, Jianming; Xiao, Jianfeng; Han, Chaofeng; Li, Nan; Shen, Xu; Jiang, Hualiang; Cao, Xuetao

2010-01-01

hPEBP4 (human phosphatidylethanolamine-binding protein 4) has been identified to be able to potentiate the resistance of breast, prostate, and ovarian cancers, with the preferential expression of hPEBP4, to tumor necrosis factor-α (TNF-α) or tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis, suggesting that inhibitors targeting the anti-apoptotic protein hPEBP4 may be useful to increase the sensitivity of hPEBP4-expressing cancer cells to TNF-α or TRAIL-induced apoptosis. By structure-based virtual screening and following surface plasmon resonance-based binding assay, seven small compounds were found to potently bind with hPEBP4. The hit compounds were further functionally screened for their ability to inhibit cancer cell growth, and one small compound, IOI-42, was identified to be able to promote TNF-α-mediated growth inhibition of MCF-7 breast cancer cells. IOI-42 could potentiate TNF-α-induced apoptosis of MCF-7 cells by inhibiting hPEBP4 and could suppress anchorage-independent cell growth of MCF-7 cells. We further demonstrated that IOI-42 could reduce the endogenous association of hPEBP4 with Raf-1/MEK1 and enhance the activation of ERK1/2 and JNK while inhibiting Akt activation. Furthermore, IOI-42 also promoted TRAIL-induced cell apoptosis of prostate cancer cells. Taken together, our data suggest that IOI-42, as the first chemical inhibitor of anti-apoptotic protein hPEBP4, may serve as a potential anti-tumor drug by sensitizing tumor cells to apoptotic inducers. PMID:20177075

B7-H4 as a Target for Breast Cancer Immunotherapy

DTIC Science & Technology

2012-06-01

lymphoma and leukemia cell lines. CEM, Karpas 299, and TLBR -1, cell lines derived from acute T-cell lymphoblastic leukemia, large cell anaplastic...Accomplishments  Generation of human B7-H4-Fc fusion protein (antigen).  Discovery of a B7-H4 receptor on CEM, Karpas 299, and TLBR -1 cell lines...CEM Karpas 299 TLBR -1 Jurkat B7-H4R Figure 3. B7-H4 binding to human T-cell lymphoma cell lines. Red

Cytotoxic and genotoxic potential of Cr(VI), Cr(III)-nitrate and Cr(III)-EDTA complex in human hepatoma (HepG2) cells.

PubMed

Novotnik, Breda; Ščančar, Janez; Milačič, Radmila; Filipič, Metka; Žegura, Bojana

2016-07-01

Chromium (Cr) and ethylenediaminetetraacetate (EDTA) are common environmental pollutants and can be present in high concentrations in surface waters at the same time. Therefore, chelation of Cr with EDTA can occur and thereby stable Cr(III)-EDTA complex is formed. Since there are no literature data on Cr(III)-EDTA toxicity, the aim of our work was to evaluate and compare Cr(III)-EDTA cytotoxic and genotoxic activity with those of Cr(VI) and Cr(III)-nitrate in human hepatoma (HepG2) cell line. First the effect of Cr(VI), Cr(III)-nitrate and Cr(III)-EDTA on cell viability was studied in the concentration range from 0.04 μg mL(-1) to 25 μg mL(-1) after 24 h exposure. Further the influence of non-cytotoxic concentrations of Cr(VI), Cr(III)-nitrate and Cr(III)-EDTA on DNA damage and genomic stability was determined with the comet assay and cytokinesis block micronucleus cytome assay, respectively. Cell viability was decreased only by Cr(VI) at concentrations above 1.0 μg mL(-1). Cr(VI) at ≥0.2 μg mL(-1) and Cr(III) at ≥1.0 μg mL(-1) induced DNA damage, while after Cr(III)-EDTA exposure no formation DNA strand breaks was determined. Statistically significant formation of micronuclei was induced only by Cr(VI) at ≥0.2 μg mL(-1), while no influence on the frequency of nuclear buds nor nucleoplasmic bridges was observed at any exposure. This study provides the first evidence that Cr(III)-EDTA did not induce DNA damage and had no influence on the genomic stability of HepG2 cells. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of GSTM1, GSTT1, and GSTP1 IIe105Val polymorphisms on susceptiblity to gestational diabetes mellitus.

PubMed

Qiu, Y H; Xu, Y L; Zhang, W H

2016-06-03

We investigate the role of the GSTM1, GSTT1, and GSTP1 IIe105Val genetic polymorphisms in the susceptibility to gestational diabetes mellitus. A total of 223 pregnant women with gestational diabetes mellitus and 265 healthy pregnant women were examined at The Second Affiliated Hospital of Shaanxi University of Chinese Medicine from May 2013 to November 2013. Genotyping for detection of GSTM1, GSTT1, and GSTP1 IIe105Val polymorphisms was conducted using the restriction fragment length polymorphism-polymerase chain reaction. There were statistically significant differences between patients with gestational diabetes mellitus and control subjects in terms of age (χ(2) = 6.68, P = 0.01) and BMI (t = 7.56, P < 0.001) levels of HDL-C (t = 2.62, P = 0.005) and LDL-C (t = 3.98, P < 0.001). By the chi-square test, we found significant differences between the present and null genotype distributions of GSTM1 (χ(2) = 10.95, P = 0.0009). Null genotype of GSTM1 could influence the susceptibility to gestational diabetes mellitus compared to the present genotype [adjusted OR (95%CI) = 1.85 (1.26-2.72)]. However, the unconditional logistic analysis revealed that GSTT1 and GSTP1 IIe105Val polymorphisms could not influence the risk of gestational diabetes mellitus in a Chinese population. In summary, we suggest that the GSTM1 gene polymorphism could influence the susceptibility to gestational diabetes mellitus in a Chinese population.

Developing Inventory Records Using the AppleWorks Data Base Subprogram and Apple IIe or GS Computers.

ERIC Educational Resources Information Center

Schlenker, Richard M.

This manual is a "how to" training device for developing inventory records in the AppleWorks program using an Apple IIe or Apple IIGS Computer with Duodisk or two disk drives and an 80-column card. The manual provides step-by-step directions, and includes 17 figures depicting the computer screen at the various stages of the inventory…

Measuring and modeling of binary mixture effects of pharmaceuticals and nickel on cell viability/cytotoxicity in the human hepatoma derived cell line HepG2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rudzok, S., E-mail: susanne.rudzok@ufz.d; Schlink, U., E-mail: uwe.schlink@ufz.d; Herbarth, O., E-mail: olf.herbarth@medizin.uni-leipzig.d

2010-05-01

The interaction of drugs and non-therapeutic xenobiotics constitutes a central role in human health risk assessment. Still, available data are rare. Two different models have been established to predict mixture toxicity from single dose data, namely, the concentration addition (CA) and independent action (IA) model. However, chemicals can also act synergistic or antagonistic or in dose level deviation, or in a dose ratio dependent deviation. In the present study we used the MIXTOX model (EU project ENV4-CT97-0507), which incorporates these algorithms, to assess effects of the binary mixtures in the human hepatoma cell line HepG2. These cells possess a liver-likemore » enzyme pattern and a variety of xenobiotic-metabolizing enzymes (phases I and II). We tested binary mixtures of the metal nickel, the anti-inflammatory drug diclofenac, and the antibiotic agent irgasan and compared the experimental data to the mathematical models. Cell viability was determined by three different methods the MTT-, AlamarBlue (registered) and NRU assay. The compounds were tested separately and in combinations. We could show that the metal nickel is the dominant component in the mixture, affecting an antagonism at low-dose levels and a synergism at high-dose levels in combination with diclofenac or irgasan, when using the NRU and the AlamarBlue assay. The dose-response surface of irgasan and diclofenac indicated a concentration addition. The experimental data could be described by the algorithms with a regression of up to 90%, revealing the HepG2 cell line and the MIXTOX model as valuable tool for risk assessment of binary mixtures for cytotoxic endpoints. However the model failed to predict a specific mode of action, the CYP1A1 enzyme activity.« less

CYP1A1 and CYP1A2 expression: Comparing 'humanized' mouse lines and wild-type mice; comparing human and mouse hepatoma-derived cell lines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Uno, Shigeyuki; Endo, Kaori; Ishida, Yuji

2009-05-15

Human and rodent cytochrome P450 (CYP) enzymes sometimes exhibit striking species-specific differences in substrate preference and rate of metabolism. Human risk assessment of CYP substrates might therefore best be evaluated in the intact mouse by replacing mouse Cyp genes with human CYP orthologs; however, how 'human-like' can human gene expression be expected in mouse tissues? Previously a bacterial-artificial-chromosome-transgenic mouse, carrying the human CYP1A1{sub C}YP1A2 locus and lacking the mouse Cyp1a1 and Cyp1a2 orthologs, was shown to express robustly human dioxin-inducible CYP1A1 and basal versus inducible CYP1A2 (mRNAs, proteins, enzyme activities) in each of nine mouse tissues examined. Chimeric mice carryingmore » humanized liver have also been generated, by transplanting human hepatocytes into a urokinase-type plasminogen activator(+/+){sub s}evere-combined-immunodeficiency (uPA/SCID) line with most of its mouse hepatocytes ablated. Herein we compare basal and dioxin-induced CYP1A mRNA copy numbers, protein levels, and four enzymes (benzo[a]pyrene hydroxylase, ethoxyresorufin O-deethylase, acetanilide 4-hydroxylase, methoxyresorufin O-demethylase) in liver of these two humanized mouse lines versus wild-type mice; we also compare these same parameters in mouse Hepa-1c1c7 and human HepG2 hepatoma-derived established cell lines. Most strikingly, mouse liver CYP1A1-specific enzyme activities are between 38- and 170-fold higher than human CYP1A1-specific enzyme activities (per unit of mRNA), whereas mouse versus human CYP1A2 enzyme activities (per unit of mRNA) are within 2.5-fold of one another. Moreover, both the mouse and human hepatoma cell lines exhibit striking differences in CYP1A mRNA levels and enzyme activities. These findings are relevant to risk assessment involving human CYP1A1 and CYP1A2 substrates, when administered to mice as environmental toxicants or drugs.« less

Mechanism of toxicity of the antimelanoma drug 4-hydroxyanisole in mouse hepatocytes.

PubMed

Schiller, C D; Gescher, A; Jheeta, P

1991-01-01

To elucidate the mechanism of the hepatotoxicity of 4-hydroxyanisole (4-HA), its effect on the viability of mouse hepatocytes in suspension was investigated. Cell viability was assessed by measurement of release of lactate dehydrogenase into the medium. 4-HA was cytotoxic in a concentration-dependent and time-dependent fashion with an IC50 of 0.26 mmol/l after 4 h incubation. Almost all cells were killed after exposure to 4-HA for 4 h at 0.5 mmol/l or for 2 h at 1.0 mmol/l. At 5 and 10 mmol/l, 4-HA caused less cytotoxicity and 1 mmol/l or below. On coincubation with the P450 inhibitor octylamine, 4-HA cytotoxcity was reduced, which suggests the involvement of cytochrome P450 in the hepatocytotoxicity of this drug. Induction of P450 isoenzymes IA, IIB and IIE1 by pretreatment of mice with phenobarbitone, 3-methylcholanthrene or acetone had no significant effect on the toxicity of 4-HA towards hepatocytes. Depletion of hepatic glutathione by pretreatment of mice with buthionine sulphoximine (1.6 g/kg, intraperitoneally) 4 h before cell isolation led to an increase in 4-HA cytotoxicity. Incubation with N-acetylcysteine (10 mmol/l) abolished the cytotoxicity of 4-HA (1 mmol/l). Both these results are consistent with the intermediacy of a reactive metabolite of 4-HA. Production of hydroquinone by oxidative demethylation of 4-HA as toxication mechanism can be excluded as formation of formaldehyde was not observed on incubation of 4-HA with mouse liver microsomes. 3,4-diacetoxyanisole, a prodrug of the known 4-HA metabolite 3,4-dihydroxyanisole, was not more cytotoxic towards hepatocytes than 4-HA.(ABSTRACT TRUNCATED AT 250 WORDS)

[Pseudolaric acid B induces G2/M arrest and inhibits invasion and migration in HepG2 hepatoma cells].

PubMed

Li, Shuai; Guo, Lianyi

2018-01-01

Objective To investigate the mechanisms of pseudolaric acid B (PAB) blocks cell cycle and inhibits invasion and migration in human hepatoma HepG2 cells. Methods The proliferation effect of PAB on HepG2 cells was evaluated by MTT assay. The effect of PAB on the cell cycle of HepG2 cells was analyzed by flow cytometry. Immunofluorescence cytochemical staining was applied to observe the effect of PAB on the α-tubulin polymerization and expression in HepG2 cells. Transwell TM chamber invasion assay and wound healing assay were performed to detect the influence of PAB on the migration and invasion ability of HepG2 cells. Western blotting was used to determine the expressions of α-tubulin, E-cadherin and MMP-9 in HepG2 cells after treated with PAB. Results PAB inhibited the proliferation of HepG2 cells in a dose-dependent manner and blocked the cell cycle in G2/M phase. PAB significantly changed the polymerization and decreased the expression of α-tubulin. The capacities of invasion and migration of HepG2 cells treated by PAB were significantly depressed. The protein levels of α-tubulin and MMP-9 decreased while the E-cadherin protein level increased. Conclusion PAB can inhibits the proliferation of HepG2 cells by down-regulating the expression of α-tubulin and influencing its polymerization, arresting HepG2 cells in G2/M phase. Meanwhile, PAB also can inhibit the invasion and migration of HepG2 cells by lowering cytoskeleton α-tubulin and MMP-9, and increasing E-cadherin.

Hepatitis B virus PreS1 facilitates hepatocellular carcinoma development by promoting appearance and self-renewal of liver cancer stem cells.

PubMed

Liu, Zhixin; Dai, Xuechen; Wang, Tianci; Zhang, Chengcheng; Zhang, Wenjun; Zhang, Wei; Zhang, Qi; Wu, Kailang; Liu, Fang; Liu, Yingle; Wu, Jianguo

2017-08-01

Hepatitis B virus (HBV) is a major etiologic agent of hepatocellular carcinoma (HCC). However, the molecular mechanism by which HBV infection contributes to HCC development is not fully understood. Here, we initially showed that HBV stimulates the production of cancer stem cells (CSCs)-related markers (CD133, CD117 and CD90) and CSCs-related genes (Klf4, Sox2, Nanog, c-Myc and Oct4) and facilitates the self-renewal of CSCs in human hepatoma cells. Cellular and clinical studies revealed that HBV facilitates hepatoma cell growth and migration, enhances white blood cell (WBC) production in the sera of patients, stimulates CD133 and CD117 expression in HCC tissues, and promotes the CSCs generation of human hepatoma cells and clinical cancer tissues. Detailed studies revealed that PreS1 protein of HBV is required for HBV-mediated CSCs generation. PreS1 activates CD133, CD117 and CD90 expression in normal hepatocyte derived cell line (L02) and human hepatoma cell line (HepG2 and Huh-7); facilitates L02 cells migration, growth and sphere formation; and finally enhances the abilities of L02 cells and HepG2 cells to induce tumorigeneses in nude mice. Thus, PreS1 acts as a new oncoprotein to play a key role in the appearance and self-renewal of CSCs during HCC development. Copyright © 2017 Elsevier B.V. All rights reserved.

Biomonitoring of Environmental Status and Trends (BEST) Program: selected methods for monitoring chemical contaminants and their effects in aquatic ecosystems

USGS Publications Warehouse

Schmitt, Christopher J.; Dethloff, Gail M.

2000-01-01

This document describes the suite of biological methods of the U.S. Geological Survey- Biomonitoring of Environmental Status and Trends program for monitoring chemical contaminants and their effects on fish. The methods, which were selected by panels of experts, are being field-tested in rivers of the Mississippi River, Columbia River, and Rio Grande basins. General health biomarkers include a health assessment index based on gross observation; histopathological examination of selected organs and tissues; condition factor; and the heptosomatic and splenosomatic indices. Immune system indicators are plasma lysozyme activity and measures of splenic macrophage aggregates. Reproductive biomarkers include plasma concentrations of sex steroid hormones (17b-estradiol and 11-ketotestosterone) and vitellogenin, gonadal histopathology (including reproductive stage and, in females, gonadal atresia), and the gonadosomatic index. Indicators of exposure to polycyclic aromatic and polyhalogenated hydrocarbons are the H4IIE rat hepatoma cell bioassay (performed on solvent extracts of composite fish samples) and hepatic ethoxyresorufin-O-deethylase activity. Stable nitrogen isotope ratios are used to assess the trophic position of the fish and their exposure to sewage and other animal wastes. For each indicator we describe endpoint(s) and methods, and discuss the indicator?s value and limitations for contaminant monitoring and assessment.

Silencing of B7-H4 suppresses the tumorigenicity of the MGC-803 human gastric cancer cell line and promotes cell apoptosis via the mitochondrial signaling pathway.

PubMed

Zhou, Donghui; Zhou, Yong; Li, Chao; Yang, Lina

2018-04-01

B7-H4 is a transmembrane protein which is a member of the B7 superfamily. It is overexpressed in various types of cancer, including gastric cancer. However, the effects of B7-H4 on the tumorigenicity of gastric cancer and the underlying mechanisms have not yet been fully explored. Thus, the aim of this study was to examine the effects of B7-H4 on the tumorigenicity of gastric cancer cells and to elucidate the underlying mechanisms. For this purpose, B7-H4 expression in gastric cancer tissues was detected by immunohistochemical staining. The effects of B7-H4 on the biological behavior of the MGC-803 human gastric cancer cell line were examined by Cell Counting kit-8 (CCK-8) assay, cell cycle analysis, wound healing assay, Annexin V/propidium iodide staining and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay. Moreover, the expression levels of apoptotic markers, such as cleaved caspase‑3, cleaved caspase‑9, Bcl-2 and Bax were examined by western blot analysis. Immunohistochemical staining revealed that a high expression of B7-H4 was found in about 41.8% of tissues obtained from patients with gastric cancer. Comparative analysis revealed that B7-H4 expression significantly correlated with lymph node metastasis and the TNM stage. The results of CCK-8 assay, cell cycle analysis, wound healing assay, Annexin V/propidium iodide staining assay and TUNEL assay all demonstrated that the silencing of B7-H4 by small interfering RNA decreased cell proliferation, suppressed cell motility, and induced cell cycle arrest and the apoptosis of MGC-803 human gastric cancer cells. Furthermore, the results of western blot analysis indicated that the downregulation of B7-H4 induced the apoptosis of the MGC-803 cells via the mitochondrial signaling pathway through the activation of caspase‑3 and caspase‑9, and by altering the Bax/Bcl-2 ratio in a manner that favored apoptosis. Based on the findings on human gastric cancer cell line MGC-803, the

Cells for bioartificial liver devices: the human hepatoma-derived cell line C3A produces urea but does not detoxify ammonia.

PubMed

Mavri-Damelin, Demetra; Damelin, Leonard H; Eaton, Simon; Rees, Myrddin; Selden, Clare; Hodgson, Humphrey J F

2008-02-15

Extrahepatic bioartificial liver devices should provide an intact urea cycle to detoxify ammonia. The C3A cell line, a subclone of the hepatoma-derived HepG2 cell line, is currently used in this context as it produces urea, and this has been assumed to be reflective of ammonia detoxification via a functional urea cycle. However, based on our previous findings of perturbed urea-cycle function in the non-urea producing HepG2 cell line, we hypothesized that the urea produced by C3A cells was via a urea cycle-independent mechanism, namely, due to arginase II activity, and therefore would not detoxify ammonia. Urea was quantified using (15)N-ammonium chloride metabolic labelling with gas chromatography-mass spectrometry. Gene expression was determined by real-time reverse transcriptase-PCR, protein expression by western blotting, and functional activities with radiolabelling enzyme assays. Arginase inhibition studies used N(omega)-hydroxy-nor-L-arginine. Urea was detected in C3A conditioned medium; however, (15)N-ammonium chloride-labelling indicated that (15)N-ammonia was not incorporated into (15)N-labelled urea. Further, gene expression of two urea cycle genes, ornithine transcarbamylase and arginase I, were completely absent. In contrast, arginase II mRNA and protein was expressed at high levels in C3A cells and was inhibited by N(omega)-hydroxy-nor-L-arginine, which prevented urea production, thereby indicating a urea cycle-independent pathway. The urea cycle is non-functional in C3A cells, and their urea production is solely due to the presence of arginase II, which therefore cannot provide ammonia detoxification in a bioartificial liver system. This emphasizes the continued requirement for developing a component capable of a full repertoire of liver function. (c) 2007 Wiley Periodicals, Inc.

Lipopolysaccharide stimulates HepG2 human hepatoma cells in the presence of lipopolysaccharide-binding protein via CD14.

PubMed

Nanbo, A; Nishimura, H; Muta, T; Nagasawa, S

1999-02-01

Lipopolysaccharide (LPS)-binding protein (LBP), an opsonin for activation of macrophages by bacterial LPS, is synthesized in hepatocytes and is known to be an acute phase protein. Recently, cytokine-induced production of LBP was reported to increase 10-fold in hepatocytes isolated from LPS-treated rats, compared with those from normal rats. However, the mechanism by which the LPS treatment enhances the effect of cytokines remains to be clarified. In the present study, we examined whether LPS alone or an LPS/LBP complex directly stimulates the hepatocytes, leading to acceleration of the cytokine-induced LBP production. HepG2 cells (a human hepatoma cell line) were shown to express CD14, a glycosylphosphatidylinositol-anchored LPS receptor, by both RT/PCR and flow cytometric analyses. An LPS/LBP complex was an effective stimulator for LBP and CD14 production in HepG2 cells, but stimulation of the cells with either LPS or LBP alone did not significantly accelerate the production of these proteins. The findings were confirmed by semiquantitative RT/PCR analysis of mRNA levels of LBP and CD14 in HepG2 cells after stimulation with LPS alone and an LPS/LBP complex. In addition, two monoclonal antibodies (mAbs) to CD14 (3C10 and MEM-18) inhibited LPS/LBP-induced cellular responses of HepG2 cells. Furthermore, prestimulation of HepG2 cells with LPS/LBP augmented cytokine-induced production and gene expression of LBP and CD14. All these findings suggest that an LPS/LBP complex, but not free LPS, stimulates HepG2 cells via CD14 leading to increased basal and cytokine-induced LBP and CD14 production.

Chalcone-Induced Apoptosis through Caspase-Dependent Intrinsic Pathways in Human Hepatocellular Carcinoma Cells

PubMed Central

Ramirez-Tagle, Rodrigo; Escobar, Carlos A.; Romero, Valentina; Montorfano, Ignacio; Armisén, Ricardo; Borgna, Vincenzo; Jeldes, Emanuel; Pizarro, Luis; Simon, Felipe; Echeverria, Cesar

2016-01-01

Hepatocellular carcinoma (HCC) is one of the most commonly diagnosed cancers worldwide. Chemoprevention of HCC can be achieved through the use of natural or synthetic compounds that reverse, suppress or prevent the development of cancer progression. In this study, we investigated the antiproliferative effects and the mechanism of action of two compounds, 2,3,4′-trimethoxy-2′-hydroxy-chalcone (CH1) and 3′-bromo-3,4-dimethoxy-chalcone (CH2), over human hepatoma cells (HepG2 and Huh-7) and cultured mouse hepatocytes (HepM). Cytotoxic effects were observed over the HepG2 and Huh-7, and no effects were observed over the HepM. For HepG2 cells, treated separately with each chalcone, typical apoptotic laddering and nuclear condensation were observed. Additionally, the caspases and Bcl-2 family proteins activation by using Western blotting and immunocytochemistry were studied. Caspase-8 was not activated, but caspase-3 and -9 were both activated by chalcones in HepG2 cells. Chalcones also induced reactive oxygen species (ROS) accumulation after 4, 8 and 24 h of treatment in HepG2 cells. These results suggest that apoptosis in HepG2 was induced through: (i) a caspase-dependent intrinsic pathway; and (ii) by alterations in the cellular levels of Bcl-2 family proteins, and also, that the chalcone moiety could be a potent candidate as novel anticancer agents acting on human hepatomas. PMID:26907262

Chalcone-Induced Apoptosis through Caspase-Dependent Intrinsic Pathways in Human Hepatocellular Carcinoma Cells.

PubMed

Ramirez-Tagle, Rodrigo; Escobar, Carlos A; Romero, Valentina; Montorfano, Ignacio; Armisén, Ricardo; Borgna, Vincenzo; Jeldes, Emanuel; Pizarro, Luis; Simon, Felipe; Echeverria, Cesar

2016-02-22

Hepatocellular carcinoma (HCC) is one of the most commonly diagnosed cancers worldwide. Chemoprevention of HCC can be achieved through the use of natural or synthetic compounds that reverse, suppress or prevent the development of cancer progression. In this study, we investigated the antiproliferative effects and the mechanism of action of two compounds, 2,3,4'-trimethoxy-2'-hydroxy-chalcone (CH1) and 3'-bromo-3,4-dimethoxy-chalcone (CH2), over human hepatoma cells (HepG2 and Huh-7) and cultured mouse hepatocytes (HepM). Cytotoxic effects were observed over the HepG2 and Huh-7, and no effects were observed over the HepM. For HepG2 cells, treated separately with each chalcone, typical apoptotic laddering and nuclear condensation were observed. Additionally, the caspases and Bcl-2 family proteins activation by using Western blotting and immunocytochemistry were studied. Caspase-8 was not activated, but caspase-3 and -9 were both activated by chalcones in HepG2 cells. Chalcones also induced reactive oxygen species (ROS) accumulation after 4, 8 and 24 h of treatment in HepG2 cells. These results suggest that apoptosis in HepG2 was induced through: (i) a caspase-dependent intrinsic pathway; and (ii) by alterations in the cellular levels of Bcl-2 family proteins, and also, that the chalcone moiety could be a potent candidate as novel anticancer agents acting on human hepatomas.

Bioreactor engineering using disposable technology for enhanced production of hCTLA4Ig in transgenic rice cell cultures.

PubMed

Kwon, Jun-Young; Yang, Yong-Suk; Cheon, Su-Hwan; Nam, Hyung-Jin; Jin, Gi-Hong; Kim, Dong-Il

2013-09-01

Two kinds of disposable bioreactors, air-lift disposable bioreactors (ADB) and wave disposable bioreactors (WDB) were compared with stirred-tank reactors (5-L STR). These bioreactors were successfully applied to transgenic rice cell cultures for the production of recombinant human cytotoxic T-lymphocyte antigen 4-immunoglobulin (hCTLA4Ig). In both systems, a fed-batch culture method was used to produce hCTLA4Ig efficiently by feeding concentrated amino acids and production levels were enhanced when dissolved oxygen (DO) level was regulated at 30% using pure oxygen sparging. Agitation and aeration rate during cultivation in ADB and WDB were determined by the same mixing time. The results in both disposable bioreactors showed similar values in maximum cell density (11.9 gDCW/L and 12.6 gDCW/L), doubling time (4.8- and 5.0-day), and maximum hCTLA4Ig concentration (43.7 and 43.3 mg/L). Relatively higher cell viability was sustained in the ADB whereas hCTLA4Ig productivity was 1.2-fold higher than that in WDB. The productivity was improved by increasing aeration rate (0.2 vvm). Overall, our experiments demonstrate pneumatically driven disposable bioreactors are applicable for the production of recombinant proteins in plant cell cultures. These results will be useful for development and scale-up studies of disposable bioreactor systems for transgenic plant cell cultures. Copyright © 2013 Wiley Periodicals, Inc.

Effects of drugs in subtoxic concentrations on the metabolic fluxes in human hepatoma cell line Hep G2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Niklas, Jens; Noor, Fozia, E-mail: fozia.noor@mx.uni-saarland.d; Heinzle, Elmar

2009-11-01

Commonly used cytotoxicity assays assess the toxicity of a compound by measuring certain parameters which directly or indirectly correlate to the viability of the cells. However, the effects of a given compound at concentrations considerably below EC{sub 50} values are usually not evaluated. These subtoxic effects are difficult to identify but may eventually cause severe and costly long term problems such as idiosyncratic hepatotoxicity. We determined the toxicity of three hepatotoxic compounds, namely amiodarone, diclofenac and tacrine on the human hepatoma cell line Hep G2 using an online kinetic respiration assay and analysed the effects of subtoxic concentrations of thesemore » drugs on the cellular metabolism by using metabolic flux analysis. Several changes in the metabolism could be detected upon exposure to subtoxic concentrations of the test compounds. Upon exposure to diclofenac and tacrine an increase in the TCA-cycle activity was observed which could be a signature of an uncoupling of the oxidative phosphorylation. The results indicate that metabolic flux analysis could serve as an invaluable novel tool for the investigation of the effects of drugs. The described methodology enables tracking the toxicity of compounds dynamically using the respiration assay in a range of concentrations and the metabolic flux analysis permits interesting insights into the changes in the central metabolism of the cell upon exposure to drugs.« less

Involvement of the histamine H{sub 4} receptor in clozapine-induced hematopoietic toxicity: Vulnerability under granulocytic differentiation of HL-60 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goto, Aya; Mouri, Akihiro; Nagai, Tomoko

Clozapine is an effective antipsychotic for treatment-resistant schizophrenia, but can cause fatal hematopoietic toxicity as agranulocytosis. To elucidate the mechanism of hematopoietic toxicity induced by clozapine, we developed an in vitro assay system using HL-60 cells, and investigated the effect on hematopoiesis. HL-60 cells were differentiated by all-trans retinoic acid (ATRA) into three states according to the following hematopoietic process: undifferentiated HL-60 cells, those undergoing granulocytic ATRA-differentiation, and ATRA-differentiated granulocytic cells. Hematopoietic toxicity was evaluated by analyzing cell survival, cell proliferation, granulocytic differentiation, apoptosis, and necrosis. In undifferentiated HL-60 cells and ATRA-differentiated granulocytic cells, both clozapine (50 and 100 μM)more » and doxorubicin (0.2 µM) decreased the cell survival rate, but olanzapine (1–100 µM) did not. Under granulocytic differentiation for 5 days, clozapine, even at a concentration of 25 μM, decreased survival without affecting granulocytic differentiation, increased caspase activity, and caused apoptosis rather than necrosis. Histamine H{sub 4} receptor mRNA was expressed in HL-60 cells, whereas the expression decreased under granulocytic ATRA-differentiation little by little. Both thioperamide, a histamine H{sub 4} receptor antagonist, and DEVD-FMK, a caspase-3 inhibitor, exerted protection against clozapine-induced survival rate reduction, but not of live cell counts. 4-Methylhistamine, a histamine H{sub 4} receptor agonist, decreased the survival rate and live cell counts, as did clozapine. HL-60 cells under granulocytic differentiation are vulnerable under in vitro assay conditions to hematopoietic toxicity induced by clozapine. Histamine H{sub 4} receptor is involved in the development of clozapine-induced hematopoietic toxicity through apoptosis, and may be a potential target for preventing its occurrence through granulocytic

Plectin deficiency in liver cancer cells promotes cell migration and sensitivity to sorafenib treatment.

PubMed

Cheng, Chiung-Chi; Chao, Wei-Ting; Liao, Chen-Chun; Tseng, Yu-Hui; Lai, Yen-Chang Clark; Lai, Yih-Shyong; Hsu, Yung-Hsiang; Liu, Yi-Hsiang

2018-01-02

Plectin involved in activation of kinases in cell signaling pathway and plays important role in cell morphology and migration. Plectin knockdown promotes cell migration by activating focal adhesion kinase and Rac1-GTPase activity in liver cells. Sorafenib is a multi-targeting tyrosine kinase inhibitor that improves patient survival on hepatocellular carcinoma. The aim of this study is to investigate the correlation between the expression of plectin and cell migration as well as the sensitivity of hepatoma cell lines exposing to sorafenib. Hepatoma cell lines PLC/PRF/5 and HepG2 were used to examine the level of plectin expression and cell migration in comparison with Chang liver cell line. In addition, sensitivity of the 3 cell lines to sorafenib treatment was also measured. Expression of plectin was lower in PLC/PRF/5 and HepG2 hepatoma cells than that of Chang liver cells whereas HepG2 and PLC/PRF/5 cells exhibit higher rate of cell migration in trans-well migration assay. Immunohistofluorecent staining on E-cadherin revealed the highest rate of collective cell migration in HepG2 cells and the lowest was found in Chang liver cells. Likewise, HepG2 cell line was most sensitive to sorafenib treatment and Chang liver cells exhibited the least sensitivity. The drug sensitivity to sorafenib treatment showed inverse correlation with the expression of plectin. We suggest that plectin deficiency and increased E-cadherin in hepatoma cells were associated with higher rates of cell motility, collective cell migration as well as higher drug sensitivity to sorafenib treatment.

CYP1A1 and CYP1A2 expression: Comparing ‘humanized’ mouse lines and wild-type mice; comparing human and mouse hepatoma-derived cell lines

PubMed Central

Uno, Shigeyuki; Endo, Kaori; Ishida, Yuji; Tateno, Chise; Makishima, Makoto; Yoshizato, Katsutoshi; Nebert, Daniel W.

2009-01-01

Human and rodent cytochrome P450 (CYP) enzymes sometimes exhibit striking species-specific differences in substrate preference and rate of metabolism. Human risk assessment of CYP substrates might therefore best be evaluated in the intact mouse by replacing mouse Cyp genes with human CYP orthologs; however, how “human-like” can human gene expression be expected in mouse tissues? Previously a bacterial-artificial-chromosome-transgenic mouse, carrying the human CYP1A1_CYP1A2 locus and lacking the mouse Cyp1a1 and Cyp1a2 orthologs, was shown to express robustly human dioxin-inducible CYP1A1 and basal versus inducible CYP1A2 (mRNAs, proteins, enzyme activities) in each of nine mouse tissues examined. Chimeric mice carrying humanized liver have also been generated, by transplanting human hepatocytes into a urokinase-type plasminogen activator(+/+)_severe-combined-immunodeficiency (uPA/SCID) line with most of its mouse hepatocytes ablated. Herein we compare basal and dioxin-induced CYP1A mRNA copy numbers, protein levels, and four enzymes (benzo[a]pyrene hydroxylase, ethoxyresorufin O-deethylase, acetanilide 4-hydroxylase, methoxyresorufin O-demethylase) in liver of these two humanized mouse lines versus wild-type mice; we also compare these same parameters in mouse Hepa-1c1c7 and human HepG2 hepatoma-derived established cell lines. Most strikingly, mouse liver CYP1A1-specific enzyme activities are between 38- and 170-fold higher than human CYP1A1-specific enzyme activities (per unit of mRNA), whereas mouse versus human CYP1A2 enzyme activities (per unit of mRNA) are within 2.5-fold of one another. Moreover, both the mouse and human hepatoma cell lines exhibit striking differences in CYP1A mRNA levels and enzyme activities. These findings are relevant to risk assessment involving human CYP1A1 and CYP1A2 substrates, when administered to mice as environmental toxicants or drugs. PMID:19285097

Amyloid precursor protein and Presenilin 1 interaction studied by FRET in human H4 cells.

PubMed

Nizzari, Mario; Venezia, Valentina; Bianchini, Paolo; Caorsi, Valentina; Diaspro, Alberto; Repetto, Emanuela; Thellung, Stefano; Corsaro, Alessandro; Carlo, Pia; Schettini, Gennaro; Florio, Tullio; Russo, Claudio

2007-01-01

The mayor pathologic hallmarks of Alzheimer's disease (AD) are senile plaque and neurofibrillary tangles. Senile plaque are primarily made up of deposits of amyloid-beta protein, a proteolytic product derived from the amyloid precursor protein (APP). APP is a transmembrane protein detected into the endoplasmic reticulum, in the Golgi apparatus, at the cell surface, recycled by endocytosis to endosomes, whose physiological function is unclear. Presenilins (PS), are a component of gamma-secretase complex that cleave alpha-CTFs (carboxy-terminal fragment), or beta-CTFs, leaving 40 or 42 amino acids amyloid-beta peptides and 58 or 56 amino acids intracellular domains (AICD). Where the amyloid-beta peptides is generated is not clear. The study of APP-PS interaction in specific cell compartments provides a good opportunity to light upon the molecular mechanisms regulating the activity of the "gamma-secretase complex," and where beta-amyloid is generated. In our study we used a biophysical assay of protein proximity: fluorescence resonance energy transfer (FRET), that can provide information about molecular interactions when two proteins are in the close proximity (<10 nm), to examine the subcellular localization and interaction between APP and PS1 in human neuroglioma cells (H4). Confocal microscopic analysis reveals extensive colocalization in different cells' compartment, and centrosomal or microtubule organizing center (MTOC) localization of APP and PS1, but not necessarily a close molecular interaction. We used FRET to determine if APP and PS1 interact at the cell centrosome. FRET data suggest a close interaction between APP and PS1 in subcellular compartments and at the centrosome of H4 cells. Using this approach we show that APP and PS1 are closely associated in the centrosomes of the H4 cell.

Effect of ethanol on hydrogen peroxide-induced AMPK phosphorylation.

PubMed

Liangpunsakul, Suthat; Wou, Sung-Eun; Zeng, Yan; Ross, Ruth A; Jayaram, Hiremagalur N; Crabb, David W

2008-12-01

AMP-activated protein kinase (AMPK) responds to oxidative stress. Previous work has shown that ethanol treatment of cultured hepatoma cells and of mice inhibited the activity of AMPK and reduced the amount of AMPK protein. Ethanol generates oxidative stress in the liver. Since AMPK is activated by reactive oxygen species, it seems paradoxical that ethanol would inhibit AMPK in the hepatoma cells. In an attempt to understand the mechanism whereby ethanol inhibits AMPK, we studied the effect of ethanol on AMPK activation by exogenous hydrogen peroxide. The effects of ethanol, hydrogen peroxide, and inhibitors of protein phosphatase 2A (PP2A) [either okadaic acid or PP2A small interference RNA (siRNA)] on AMPK phosphorylation and activity were examined in rat hepatoma cells (H4IIEC3) and HeLa cells. In H4IIEC3 cells, hydrogen peroxide (H(2)O(2), 1 mM) transiently increased the level of phospho-AMPK to 1.5-fold over control (P < 0.05). Similar findings were observed in HeLa cells, which do not express the upstream AMPK kinase, LKB1. H(2)O(2) markedly increased the phosphorylation of LKB1 in H4IIEC3 cells. Ethanol significantly inhibited the phosphorylation of PKC-zeta, LKB1, and AMPK caused by exposure to H(2)O(2). This inhibitory effect of ethanol required its metabolism. More importantly, the inhibitory effects of ethanol on H(2)O(2)-induced AMPK phosphorylation were attenuated by the presence of the PP2A inhibitor, okadaic acid, or PP2A siRNA. The inhibitory effect of ethanol on AMPK phosphorylation is exerted through the inhibition of PKC-zeta and LKB1 phosphorylation and the activation of PP2A.

[Methylation Status of the SOCS3 Gene Promoter in H2228 Cells and 
EML4-ALK-positive Lung Cancer Tissues].

PubMed

Liu, Chunlai; Li, Yongwen; Dong, Yunlong; Zhang, Hongbing; Li, Ying; Liu, Hongyu; Chen, Jun

2016-09-20

The EML4-ALK fusion gene is a newly discovered driver gene of non-small cell lung cancer and exhibits special clinical and pathological features. The JAK-STAT signaling pathway, an important downstream signaling pathway of EML4-ALK, is aberrantly sustained and activated in EML4-ALK-positive lung cancer cells fusion gene, but the underlying reason remains unknown. The suppressor of cytokine signaling (SOCS) is a negative regulatory factor that mainly inhibits the proliferation, differentiation, and induction of apoptotic cells by inhibiting the JAK-STAT signaling pathway. The aberrant methylation of the SOCS gene leads to inactivation of tumors and abnormal activation of the JAK2-STAT signaling pathway. The aim of this study is to investigate the methylation status of the SOCS3 promoter in EML4-ALK-positive H2228 cells and lung cancer tissues. The methylation status of the SOCS3 promoter in EML4-ALK-positive H2228 lung cancer cells and lung cancer tissues was detected by methylation-specific PCR (MSP) analysis and verified by DNA sequencing. The expression levels of SOCS3 in H2228 cells were detected by Western blot and Real-time PCR analyses after treatment with the DNA methyltransferase inhibitor 5'-Aza-dC. MSP and DNA sequencing assay results indicated the presence of SOCS3 promoter methylation in H2228 cells as well as in three cases of seven EML4-ALK-positive lung cancer tissues. The expression level of SOCS3 significantly increased in H2228 cells after 5'-Aza-dC treatment. The aerrant methylation of the SOCS3 promoter region in EML4-ALK (+) H2228 cells and lung cancer tissues may be significantly involved in the pathogenesis of EML4-ALK-positive lung cancer.

Activation of AhR-mediated toxicity pathway by emerging ...

EPA Pesticide Factsheets

Polychlorinated diphenyl sulfides (PCDPSs) are a group of environmental pollutants for which limited toxicological information is available. This study tested the hypothesis that PCDPSs could activate the mammalian aryl hydrocarbon receptor (AhR) mediated toxicity pathways. Eighteen PCDPSs were tested in the H4IIE-luc transactivation assay, with 13/18 causing concentration-dependent AhR activation. Potencies of several congeners were similar to those of mono-ortho substituted polychlorinated biphenyls. A RNA sequencing (RNA-seq)-based transcriptomic analysis was performed on H4IIE cells treated with two PCDPS congeners, 2,2',3,3',4,5,6-hepta-CDPS, and 2,4,4',5-tetra-CDPS. Results of RNA-seq revealed a remarkable modulation on a relatively short gene list by exposure to the tested concentrations of PCDPSs, among which, Cyp1 responded with the greatest fold up-regulation. Both the identities of the modulated transcripts and the associated pathways were consistent with targets and pathways known to be modulated by other types of AhR agonists and there was little evidence for significant off-target effects within the cellular context of the H4IIE bioassay. The results suggest AhR activation as a toxicologically relevant mode of action for PCDPSs suggests the utility of AhR-related toxicity pathways for predicting potential hazards associated with PCDPS exposure in mammals and potentially other vertebrates. Polychlorinated diphenyl sulfides (PCDPSs) are a group of en

Building Parts Inventory Files Using the AppleWorks Data Base Subprogram and Apple IIe or GS Computers.

ERIC Educational Resources Information Center

Schlenker, Richard M.

This manual is a "how to" training device for building database files using the AppleWorks program with an Apple IIe or Apple IIGS Computer with Duodisk or two disk drives and an 80-column card. The manual provides step-by-step directions, and includes 25 figures depicting the computer screen at the various stages of the database file…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Yu; Wang, Wenhui; Wang, Qi

Highlights: Black-Right-Pointing-Pointer 5-LOX is able to upregulate expression of NF-{kappa}B p65. Black-Right-Pointing-Pointer 5-LOX enhances nuclear translocation of NF-{kappa}B p65 via increasing p-I{kappa}B-{alpha} level. Black-Right-Pointing-Pointer 5-LOX stimulates transcriptional activity of NF-{kappa}B in hepatoma cells. Black-Right-Pointing-Pointer LTB4 activates transcriptional activity of NF-{kappa}B in hepatoma cells. -- Abstract: The issue that lipid metabolism enzyme and its metabolites regulate transcription factors in cancer cell is not fully understood. In this study, we first report that the lipid metabolism enzyme 5-Lipoxygenase (5-LOX) and its metabolite leukotriene B4 (LTB4) are capable of activating nuclear factor-{kappa}B (NF-{kappa}B) in hepatoma cells. We found that the treatment of MK886more » (an inhibitor of 5-LOX) or knockdown of 5-LOX was able to downregulate the expression of NF-{kappa}B p65 at the mRNA level and decreased the phosphorylation level of inhibitor {kappa}B{alpha} (I{kappa}B{alpha}) in the cytoplasm of hepatoma HepG2 or H7402 cells, which resulted in the decrease of the level of nuclear NF-{kappa}B p65. These were confirmed by immunofluorescence staining in HepG2 cell. Moreover, the above treatments were able to decrease the transcriptional activity of NF-{kappa}B in the cells. The LTB4, one of metabolites of 5-LOX, is responsible for 5-LOX-activated NF-{kappa}B in a dose-dependent manner. Thus, we conclude that the lipid metabolism enzyme 5-LOX and its metabolite LTB4 are capable of activating transcription factor NF-{kappa}B in hepatoma cells. Our finding provides new insight into the significance of lipid metabolism in activation of transcription factors in cancer.« less

Synthesis and cytotoxic evaluation of some new 4(3H)-quinazolinones on HeLa cell line

PubMed Central

Khodarahmi, G.A.; Shamshiri, M.; Hassanzadeh, F.

2012-01-01

Quinazolinone backbone is present in a large number of bioactive substances. Since remarkable cytotoxic activity is associated with some 4(3H)-quinazolinones, in this study some 4(3H)-quinazolinone were synthesized and screened against HeLa cells. The synthesis was performed via reaction of anthranilic acid with dicarboxylic anhydrides to produce carboxylic acids derivatives. The products were heated in acetic anhydride to produce benzoxazinones. Finally, 4(3H)-quinazolinones were synthesized by reaction between benzoxazinones and primary amines. The assessment of the structure of the synthesized compounds was based on spectral data (FT-IR, Mass and 1HNMR). Subsequently, cytotoxic activity of compounds 3, 6, 9 and 13 (individually and in combination with doxorubicin) was evaluated on HeLa cell line using MTT assay. The results indicated that the tested compounds did not show significant cytotoxicity alone and in combination with doxorubicin (1 and 20 μM). PMID:23181089

Isatis indigotica induces hepatocellular cancer cell death via caspase-independent apoptosis-inducing factor translocation apoptotic pathway in vitro and in vivo.

PubMed

Chung, Ying-Cheng; Tang, Feng-Yao; Liao, Jiunn-Wang; Chung, Chia-Hua; Jong, Ting-Ting; Chen, Shih-Shiung; Tsai, Ching-Hsiu; Chiang, En-Pei

2011-06-01

Isatis indigotica is a biennial herbaceous cruciferous medical herb with antipyretic, antiviral, anti-inflammatory, and anti-endotoxin activity. This study explored the chemotherapeutic potential of I indigotica on human hepatoma cells and investigated the mechanism by which metabolites from I indigotica inhibit hepatoma cell growth. Antitumor activity was discovered in dried I indigotica leaf chloroform extracts (CEDLI). In nude mice xenotransplanted with human hepatoma cells, CEDLI supplementation inhibited tumor growth by ~40% compared with nonsupplemented animals without affecting body weight/food intake. CEDLI induced sub-G1 cell cycle arrest and apoptosis in hepatoma cells. Furthermore, CEDLI activates p53 and Bax, reduces Bcl-2 expression, and causes mitochondrial stress and the release of apoptosis-inducing factor into the cytosol followed by its translocation into the nucleus, resulting in hepatoma cell apoptosis. This study provides novel in vivo evidence of I indigotica's antitumor activity. The chemotherapeutic activity against human hepatoma tumorigenesis was because of a distinguished caspase-independent apoptotic pathway.

Inhibition of liver fibrosis by solubilized coenzyme Q10: Role of Nrf2 activation in inhibiting transforming growth factor-beta1 expression

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choi, Hoo-Kyun; Pokharel, Yuba Raj; Lim, Sung Chul

2009-11-01

Coenzyme Q10 (CoQ10), an endogenous antioxidant, is important in oxidative phosphorylation in mitochondria. It has anti-diabetic and anti-cardiovascular disease effects, but its ability to protect against liver fibrosis has not been studied. Here, we assessed the ability of solubilized CoQ10 to improve dimethylnitrosamine (DMN)-induced liver fibrogenesis in mice. DMN treatments for 3 weeks produced a marked liver fibrosis as assessed by histopathological examination and tissue 4-hydroxyproline content. Solubilized CoQ10 (10 and 30 mg/kg) significantly inhibited both the increases in fibrosis score and 4-hydroxyproline content induced by DMN. Reverse transcription-polymerase chain reaction and Western blot analyses revealed that solubilized CoQ10 inhibitedmore » increases in the transforming growth factor-beta1 (TGF-beta1) mRNA and alpha-smooth muscle actin (alpha-SMA) protein by DMN. Interestingly, hepatic glutamate-cysteine ligase (GCL) and glutathione S-transferase A2 (GSTA2) were up-regulated in mice treated with CoQ10. Solubilized CoQ10 also up-regulated antioxidant enzymes such as catalytic subunits of GCL and GSTA2 via activating NF-E2 related factor2 (Nrf2)/antioxidant response element (ARE) in H4IIE hepatoma cells. Moreover, CoQ10's inhibition of alpha-SMA and TGF-beta1 expressions disappeared in Nrf2-null MEF cells. In contrast, Nrf2 overexpression significantly decreased the basal expression levels of alpha-SMA and TGF-beta1 in Nrf2-null MEF cells. These results demonstrated that solubilized CoQ10 inhibited DMN-induced liver fibrosis through suppression of TGF-beta1 expression via Nrf2/ARE activation.« less

GATA4 promotes hepatoblastoma cell proliferation by altering expression of miR125b and DKK3.

PubMed

Pei, Yihua; Yao, Qin; Yuan, Sibo; Xie, Bozhen; Liu, Yan; Ye, Chunsheng; Zhuo, Huiqin

2016-11-22

GATA4 is a zinc finger DNA-binding protein that plays an important role in mammalian liver development. However, the effects of GATA4 in hepatoblastoma (HB), a common liver cancer in pediatric patients, remain largely unknown. In this study, we demonstrate that GATA4 promotes growth and survival in the Huh6 human hepatoblastoma cell line. GATA4 expression was high in Huh6 cells, and its knockdown decreased expression of Dickkopf-related protein 3 (DKK3), a gene that may contribute to premature or undifferentiated phenotypes in HB. GATA4 also directly bound to the promoter regions of the miRNA miR125b and inhibited its expression in Huh6 cells. DKK3 was a direct target of miR125b in Huh6 cells. Inhibition of miR125b or overexpression of DKK3 promoted proliferation, survival, migration, and invasion in Huh6 cells. This is the first report to demonstrate that GATA4 promotes oncogenesis by inhibiting miR125b-dependent suppression of DKK3 expression. This GATA4/miR125b/DKK3 axis may be a major regulator of growth, migration, invasion, and survival in hepatoma cells, and is therefore a potential therapeutic target or biomarker for progression in HB patients.

Vildagliptin and its metabolite M20.7 induce the expression of S100A8 and S100A9 in human hepatoma HepG2 and leukemia HL-60 cells

PubMed Central

Asakura, Mitsutoshi; Karaki, Fumika; Fujii, Hideaki; Atsuda, Koichiro; Itoh, Tomoo; Fujiwara, Ryoichi

2016-01-01

Vildagliptin is a potent, orally active inhibitor of dipeptidyl peptidase-4 (DPP-4) for the treatment of type 2 diabetes mellitus. It has been reported that vildagliptin can cause hepatic dysfunction in patients. However, the molecular-mechanism of vildagliptin-induced liver dysfunction has not been elucidated. In this study, we employed an expression microarray to determine hepatic genes that were highly regulated by vildagliptin in mice. We found that pro-inflammatory S100 calcium-binding protein (S100) a8 and S100a9 were induced more than 5-fold by vildagliptin in the mouse liver. We further examined the effects of vildagliptin and its major metabolite M20.7 on the mRNA expression levels of S100A8 and S100A9 in human hepatoma HepG2 and leukemia HL-60 cells. In HepG2 cells, vildagliptin, M20.7, and sitagliptin – another DPP-4 inhibitor – induced S100A9 mRNA. In HL-60 cells, in contrast, S100A8 and S100A9 mRNAs were significantly induced by vildagliptin and M20.7, but not by sitagliptin. The release of S100A8/A9 complex in the cell culturing medium was observed in the HL-60 cells treated with vildagliptin and M20.7. Therefore, the parental vildagliptin- and M20.7-induced release of S100A8/A9 complex from immune cells, such as neutrophils, might be a contributing factor of vildagliptin-associated liver dysfunction in humans. PMID:27759084

Vildagliptin and its metabolite M20.7 induce the expression of S100A8 and S100A9 in human hepatoma HepG2 and leukemia HL-60 cells.

PubMed

Asakura, Mitsutoshi; Karaki, Fumika; Fujii, Hideaki; Atsuda, Koichiro; Itoh, Tomoo; Fujiwara, Ryoichi

2016-10-19

Vildagliptin is a potent, orally active inhibitor of dipeptidyl peptidase-4 (DPP-4) for the treatment of type 2 diabetes mellitus. It has been reported that vildagliptin can cause hepatic dysfunction in patients. However, the molecular-mechanism of vildagliptin-induced liver dysfunction has not been elucidated. In this study, we employed an expression microarray to determine hepatic genes that were highly regulated by vildagliptin in mice. We found that pro-inflammatory S100 calcium-binding protein (S100) a8 and S100a9 were induced more than 5-fold by vildagliptin in the mouse liver. We further examined the effects of vildagliptin and its major metabolite M20.7 on the mRNA expression levels of S100A8 and S100A9 in human hepatoma HepG2 and leukemia HL-60 cells. In HepG2 cells, vildagliptin, M20.7, and sitagliptin - another DPP-4 inhibitor - induced S100A9 mRNA. In HL-60 cells, in contrast, S100A8 and S100A9 mRNAs were significantly induced by vildagliptin and M20.7, but not by sitagliptin. The release of S100A8/A9 complex in the cell culturing medium was observed in the HL-60 cells treated with vildagliptin and M20.7. Therefore, the parental vildagliptin- and M20.7-induced release of S100A8/A9 complex from immune cells, such as neutrophils, might be a contributing factor of vildagliptin-associated liver dysfunction in humans.

Potentiating effect of graphene nanomaterials on aromatic environmental pollutant-induced cytochrome P450 1A expression in the topminnow fish hepatoma cell line PLHC-1.

PubMed

Lammel, Tobias; Boisseaux, Paul; Navas, José M

2015-09-01

Graphene and its derivatives are an emerging class of carbon nanomaterial with great potential for a broad range of industrial and consumer applications. However, their increasing production and use is expected to result in release of nano-sized graphene platelets into the environment, where they may interact with chemical pollutants modifying their fate and toxic potential. The objective of this study was to assess whether graphene nanoplatelets can act as vector for aromatic environmental pollutants increasing their cellular uptake and associated hazardous effects in vitro. For this purpose, cell cultures of the topminnow fish (Poeciliopsis lucida) hepatoma cell line PLHC-1 were simultaneously (and successively) exposed to graphene nanoplatelets (graphene oxide (GO) or carboxyl graphene (CXYG)) and an aryl hydrocarbon receptor (AhR) agonist (β-naphthoflavone (β-NF), benzo(k)fluoranthene (BkF) or 3,3',4,4',5,5'-hexachlorobiphenyl (PCB169)). Following exposure cytochrome P450 1A (Cyp1A) induction was assessed by measuring cyp1A mRNA expression levels using reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) and Cyp1A-dependent ethoxyresorufin-O-deethylase (EROD) activity. It was observed that pre- and co-exposure of cells to GO and CXYG nanoplatelets had a potentiating effect on β-NF, BkF, and PCB169-dependent Cyp1A induction suggesting that graphene nanoplatelets increase the effective concentration of AhR agonists by facilitating their passive diffusion into the cells by damaging the cells' plasma membrane and/or by transporting them over the plasma membrane via a Trojan horse-like mechanism. The results demonstrate the existence of combination effects between nanomaterials and environmental pollutants and stress the importance of considering these effects when evaluating their respective hazard. © 2014 Wiley Periodicals, Inc.

Cyclic Mechanical Stretch Up-regulates Hepatoma-Derived Growth Factor Expression in Cultured Rat Aortic Smooth Muscle Cells.

PubMed

Kao, Ying-Hsien; Chen, Po-Han; Sun, Cheuk-Kwan; Chang, Yo-Chen; Lin, Yu-Chun; Tsai, Ming-Shian; Lee, Po-Huang; Cheng, Cheng-I

2018-02-21

Hepatoma-derived growth factor (HDGF) is a potent mitogen for vascular smooth muscle cells (SMCs) during embryogenesis and injury repair of vessel walls. Whether mechanical stimuli modulate HDGF expression remains unknown. This study aimed at investigating whether cyclic mechanical stretch plays a regulatory role in HDGF expression and regenerative cytokine production in aortic SMCs. A SMC cell line was grown on a silicone-based elastomer chamber with extracellular matrix coatings (either type I collagen or fibronectin) and received cyclic and uni-axial mechanical stretches with 10% deformation at frequency 1 Hz. Morphological observation showed that fibronectin coating provided better cell adhesion and spreading and that consecutive 6 hours of cyclic mechanical stretch remarkably induced reorientation and realignment of SMCs. Western blotting detection demonstrated that continuous mechanical stimuli elicited up-regulation of HDGF and PCNA, a cell proliferative marker. Signal kinetic profiling study indicated that cyclic mechanical stretch induced signaling activity in RhoA/ROCK and PI3K/Akt cascades. Kinase inhibition study further showed that blockade of PI3K activity suppressed the stretch-induced TNF-a, whereas RhoA/ROCK inhibition significantly blunted the IL-6 production and HDGF over-expression. Moreover, siRNA-mediated HDGF gene silencing significantly suppressed constitutive expression of IL-6, but not TNF-α, in SMCs. These findings support the role of HDGF in maintaining vascular expression of IL-6, which has been regarded a crucial regenerative factor for acute vascular injury. In conclusion, cyclic mechanical stretch may maintain constitutive expression of HDGF in vascular walls and be regarded an important biophysical regulator in vascular regeneration. ©2018 The Author(s).

The synergistic radiosensitizing effect of tirapazamine-conjugated gold nanoparticles on human hepatoma HepG2 cells under X-ray irradiation

PubMed Central

Liu, Xi; Liu, Yan; Zhang, Pengcheng; Jin, Xiaodong; Zheng, Xiaogang; Ye, Fei; Chen, Weiqiang; Li, Qiang

2016-01-01

Reductive drug-functionalized gold nanoparticles (AuNPs) have been proposed to enhance the damage of X-rays to cells through improving hydroxyl radical production by secondary electrons. In this work, polyethylene glycol-capped AuNPs were conjugated with tirapazamine (TPZ) moiety, and then thioctyl TPZ (TPZs)-modified AuNPs (TPZs-AuNPs) were synthesized. The TPZs-AuNPs were characterized by transmission electron microscopy, ultraviolet-visible spectra, dynamic light scattering, and inductively coupled plasma mass spectrometry to have a size of 16.6±2.1 nm in diameter and a TPZs/AuNPs ratio of ~700:1. In contrast with PEGylated AuNPs, the as-synthesized TPZs-AuNPs exhibited 20% increment in hydroxyl radical production in water at 2.0 Gy, and 19% increase in sensitizer enhancement ratio at 10% survival fraction for human hepatoma HepG2 cells under X-ray irradiation. The production of reactive oxygen species in HepG2 cells exposed to X-rays in vitro demonstrated a synergistic radiosensitizing effect of AuNPs and TPZ moiety. Thus, the reductive drug-conjugated TPZs-AuNPs as a kind of AuNP radiosensitizer with low gold loading provide a new strategy for enhancing the efficacy of radiation therapy. PMID:27555772

Low-temperature thermal decomposition of dioxin-like compounds in fly ash: combination of chemical analysis with in vitro bioassays (EROD and DR-CALUX).

PubMed

Behnisch, Peter A; Hosoe, Kazunori; Shiozaki, Ken; Ozaki, Hironori; Nakamura, Kazuo; Sakai, Shin-Ichi

2002-12-01

To investigate the dechlorination of fly ash during low-temperature treatment under oxygen-deficient conditions (thermocatalyic treatment or Hagenmaier process), six fly ash samples from six different incineration plants were treated in a laboratory experiment or in the actual plant, either under ideal (400 degrees C, 120 min) or intermediate (300 degrees C, 30 min) conditions. The aim of the present study was to confirm the decrease in the I-TEQ (international toxicity equivalency) of polychlorinated dibenzo-p-dioxins/-furans (PCDD/Fs) and coplanar polychlorinated biphenyls (co-PXBs) and, also for the first time, the decrease in the sum of dioxin-like toxicity (bioassay- or bio-TEQ) of all kinds of other dioxin-like Ah receptor agonists (such as PXDD/Fs, PXBs, PXN, X = Br, F) measured by two state-of-the-art cell-based Ah receptor-dependent bioassays: H4IIE-Ethoxy-Resorufin-o-Deethylase (EROD) and H4IIE-luc/DR-Chemical Activated Luciferase expression (DR-CALUX). The treatment efficiency was calculated on the basis of the reduction in the I-TEQ and bio-TED values. For these fly ash samples, the treatment efficiency, as measured by chemical analysis, was higher than 99%, and 85%-99%, in the case of the bio-TED values, indicating that these Ah receptor binding toxic compounds were sufficiently decomposed. Bio-TEQ values for untreated fly ash samples (n = 6) were on average 1.2 times (range 0.7-1.9), for the H4IIE-EROD assay, and 2.8 times (1.1-4.9), for the DR-CALUX assay, higher than I-TEQ values measured by chemical analyses (sum of PCDD/Fs and co-PCBs). In the case of these fly ash samples treated under ideal conditions and therefore low in contaminants, the bio-TEQ values were on average 1.4 times (range 0.9-1.8), for the H4IIE-EROD assay, and 5.1 times (range 1.2-12), for the DR-CALUX assay, higher than the I-TEQ values.

An Effect of Dexamethasone on Adenosine 3′,5′ -Monophosphate Content and Adenosine 3′,5′ -Monophosphate Phosphodiesterase Activity of Cultured Hepatoma Cells

PubMed Central

Manganiello, Vincent; Vaughan, Martha

1972-01-01

The effect of dexamethasone on adenosine 3′,5′-monophosphate (cAMP) phosphodiesterase activity in cultured HTC hepatoma cells was investigated. Homogenates of these cells contain phosphodiesterase activity with two apparent Michaelis constants for cAMP (2-5 μm and 50 μm). At all substrate concentrations tested, phosphodiesterase activity was decreased 25-40% in cells incubated for 36 hr or more with 1 μm dexamethasone. Acid phosphatase activity in the same cells was not decreased. α-Methyl testosterone, 1 μm, was without effect on phosphodiesterase activity. Incubation for 10 min with epinephrine plus theophylline increased the cAMP content of the HTC cells 3- to 6-fold. In cells incubated for 72 hr with dexamethasone, the basal concentration of cAMP was slightly increased and the increment produced by epinephrine plus theophylline was markedly increased. We believe that in many cells the so-called permissive effects of steroid hormones on cAMP mediated processes may be due to an effect of these hormones on cAMP phosphodiesterase activity similar to that observed in HTC cells incubated with dexamethasone. PMID:4341439

Purification and characterization of a novel type i ribosome inactivating protein, pachyerosin, from Pachyrhizus erosus seeds, and preparation of its immunotoxin against human hepatoma cells.

PubMed

Guo, Jin-Lin; Cheng, Yuan-Liu; Qiu, Yi; Shen, Cai-Hong; Yi, Bin; Peng, Cheng

2014-07-01

Pachyrhizus erosus seeds have a high protein content and are used in China due to their cytotoxic effect. Here we report the biological and pharmacological activity of the protein extracts from P. erosus seeds. A novel ribosome-inactivating protein, pachyerosin, from P. erosus seeds was successively purified to homogeneity using ammonium sulfate precipitation, DEAE-sepharose FF, and Sephacryl S-200. Pachyerosin showed to be a type I ribosome-inactivating protein with a molecular mass of 29 kDa and an isoelectric point of 9.19. It strongly inhibited protein synthesis of rabbit reticulocyte lysate with an IC50 of 0.37 ng/mL and showed N-glycosidase activity on rat liver ribosomes with an EC50 of 85.9 pM. The N-terminal 27 amino acids of pachyerosin revealed a 60.71% sequence identity with abrin A from the seeds of Abrus precatorius. With the aim of targeting the delivery of pachyerosin, immunotoxin was prepared by conjugating pachyerosin with anti-human AFP monoclonal antibodies SM0736. The immunotoxin pachyerosin-SM0736 efficiently inhibited the growth of the human hepatoma cell line HuH-7 with an IC50 of 0.050 ± 0.004 nM, 2360 times lower than that of pachyerosin and 430 times lower than that of the immunotoxin against human gastric cancer cell line SGC7901. These results imply that pachyerosin may be used as a new promising anticancer agent. Georg Thieme Verlag KG Stuttgart · New York.

Preexisting CD4+ T-Cell Immunity in Human Population to Avian Influenza H7N9 Virus: Whole Proteome-Wide Immunoinformatics Analyses

PubMed Central

Duvvuri, Venkata R.; Duvvuri, Bhargavi; Alice, Christilda; Wu, Gillian E.; Gubbay, Jonathan B.; Wu, Jianhong

2014-01-01

In 2013, a novel avian influenza H7N9 virus was identified in human in China. The antigenically distinct H7N9 surface glycoproteins raised concerns about lack of cross-protective neutralizing antibodies. Epitope-specific preexisting T-cell immunity was one of the protective mechanisms in pandemic 2009 H1N1 even in the absence of cross-protective antibodies. Hence, the assessment of preexisting CD4+ T-cell immunity to conserved epitopes shared between H7N9 and human influenza A viruses (IAV) is critical. A comparative whole proteome-wide immunoinformatics analysis was performed to predict the CD4+ T-cell epitopes that are commonly conserved within the proteome of H7N9 in reference to IAV subtypes (H1N1, H2N2, and H3N2). The CD4+ T-cell epitopes that are commonly conserved (∼556) were further screened against the Immune Epitope Database (IEDB) to validate their immunogenic potential. This analysis revealed that 45.5% (253 of 556) epitopes are experimentally proven to induce CD4+ T-cell memory responses. In addition, we also found that 23.3% of CD4+ T-cell epitopes have ≥90% of sequence homology with experimentally defined CD8+ T-cell epitopes. We also conducted the population coverage analysis across different ethnicities using commonly conserved CD4+ T-cell epitopes and corresponding HLA-DRB1 alleles. Interestingly, the indigenous populations from Canada, United States, Mexico and Australia exhibited low coverage (28.65% to 45.62%) when compared with other ethnicities (57.77% to 94.84%). In summary, the present analysis demonstrate an evidence on the likely presence of preexisting T-cell immunity in human population and also shed light to understand the potential risk of H7N9 virus among indigenous populations, given their high susceptibility during previous pandemic influenza events. This information is crucial for public health policy, in targeting priority groups for immunization programs. PMID:24609014

pH-induced conformational change of the rotavirus VP4 spike: implications for cell entry and antibody neutralization.

PubMed

Pesavento, Joseph B; Crawford, Sue E; Roberts, Ed; Estes, Mary K; Prasad, B V Venkataram

2005-07-01

The rotavirus spike protein, VP4, is a major determinant of infectivity and neutralization. Previously, we have shown that trypsin-enhanced infectivity of rotavirus involves a transformation of the VP4 spike from a flexible to a rigid bilobed structure. Here we show that at elevated pH the spike undergoes a drastic, irreversible conformational change and becomes stunted, with a pronounced trilobed appearance. These particles with altered spikes, at a normal pH of 7.5, despite the loss of infectivity and the ability to hemagglutinate, surprisingly exhibit sialic acid (SA)-independent cell binding in contrast to the SA-dependent cell binding exhibited by native virions. Remarkably, a neutralizing monoclonal antibody that remains bound to spikes throughout the pH changes (pH 7 to 11 and back to pH 7) completely prevents this conformational change, preserving the SA-dependent cell binding and hemagglutinating functions of the virion. A hypothesis that emerges from the present study is that high-pH treatment triggers a conformational change that mimics a post-SA-attachment step to expose an epitope recognized by a downstream receptor in the rotavirus cell entry process. This process involves sequential interactions with multiple receptors, and the mechanism by which the antibody neutralizes is by preventing this conformational change.

[Immunogenicity of chimeric gene vaccine Mtb8.4/hIL12].

PubMed

Li, Hui; Li, Rong; Zhong, Sen; Luo, Yue-bei; Ren, Hong; Deng, Cun-liang

2006-09-01

To construct chimeric gene vaccine Mtb8.4/hIL-12, express it in COS-7 cells and study its immunogenicity. Chimeric gene Mtb8.4/hIL-12 was amplified by PCR and cloned into the eukaryotic vector pCI-neo to construct the recombinant plasmid pCI-neo-Mtb8.4/hIL12. After the recombinant plasmid was identified by restriction enzyme digestion analysis, PCR and DNA sequencing, COS-7 cells were transfected with pCI-neo-Mtb8.4/hIL12 through cationic liposome. 48 hours later, the expression of mRNA was detected by RT-PCR and the level of hIL-12 in culture supernatant and cell lysates were detected by Western blot. C57BL/6N mice were vaccinated with chimeric gene vaccine Mtb8.4/hIL-12 three times at the interval of 3 weeks each time. Four weeks after the final inoculation, three mice were sacrificed to assess the cytotoxicity of CTLs and response to cytokine. The recombinant plasmid pCI-neo-Mtb8.4/hIL12 was constructed successfully. After COS-7 cells were transfected with pCI-neo-Mtb8.4/hIL12, chimeric gene Mtb8.4/hIL12 was expressed in COS-7 cells. The chimeric gene vaccine could induce strong antigen-specific immune response. With the increase of IFN-gamma and IL-2 secretion and the decrease of IL-4 secretion, the cytotoxicity of specific CTLs was heightened. Recombinant plasmid pCI-neo-Mtb8.4/hIL12 has been successfully constructed and expressed in COS-7 cells. The constructed chimeric gene vaccine Mtb8.4/hIL12 is of strong immunogenicity and can obviously induce the cytotoxicity of CTLs.

Synthesis of N4-(Substituted phenyl)-N4-alkyl/desalkyl-9H-pyrimido[4,5-b]indole-2,4-diamines and Identification of New Microtubule Disrupting Compounds that are Effective against Multidrug Resistant Cells1

PubMed Central

Gangjee, Aleem; Zaware, Nilesh; Devambatla, Ravi Kumar Vyas; Raghavan, Sudhir; Westbrook, Cara D.; Dybdal-Hargreaves, Nicholas F.; Hamel, Ernest; Mooberry, Susan L.

2013-01-01

A series of fourteen N4-(substituted phenyl)-N4-methyl/desmethyl-9H-pyrimido[4,5-b]indole-2,4-diamines was synthesized as potential microtubule targeting agents. The synthesis involved a Fisher indole cyclization of 2-amino-6-hydrazinylpyrimidin-4(3H)-one with cyclohexanone, followed by oxidation, chlorination and displacement with appropriate anilines. Compounds 6, 14 and 15 had low nanomolar potency against MDA-MB-435 tumor cells and depolymerized microtubules. Compound 6 additionally had nanomolar GI50 values against 57 of the NCI 60-tumor panel cell lines. Mechanistic studies showed that 6 inhibited tubulin polymerization and [3H]colchicine binding to tubulin. The most potent compounds were all effective in cells expressing P-glycoprotein or the βIII isotype of tubulin, which have been associated with clinical drug reisistence. Modeling studies provided the potential interactions of 6, 14 and 15 within the colchicine site. PMID:23332369

Evaluation of buffers toxicity in tobacco cells: Homopiperazine-1,4-bis (2-ethanesulfonic acid) is a suitable buffer for plant cells studies at low pH.

PubMed

Borgo, Lucélia

2017-06-01

Low pH is an important environmental stressor of plant root cells. Understanding the mechanisms of stress and tolerance to acidity is critical; however, there is no widely accepted pH buffer for studies of plant cells at low pH. Such a buffer might also benefit studies of Al toxicity, in which buffering at low pH is also important. The challenge is to find a buffer with minimal cellular effects. We examined the cytotoxicity and possible metabolic disturbances of four buffers that have adequate pK a values and potential use for studies in the pH range of 4.0-5.0. These were homopipes (homopiperazine-1,4-bis (2-ethanesulfonic acid); pK a1 4.4), 3,3-dimethylglutaric acid (pK a1 3.73), β-alanine (pK a1 3.70) and potassium biphthalate (pK a1 2.95; pK a2 5.41). First, tobacco BY-2 cells were grown in a rich medium containing 10 mM of each buffer or MES (2-(N-morpholino) ethanesulfonic acid) as a control, with the pH initially adjusted to 5.7. β-alanine was clearly toxic and dimethylgluturate and biphthalate were found to be cytostatic, in which no culture growth occurred but cell viability was either unaffected or decreased only after 5 days. Only homopipes allowed normal culture growth and cell viability. Homopipes (10 mM) was then tested in cell cultures with an initial pH of 4.3 ± 0.17 in minimal medium to examine whether its undissociated species (H 2 A) displayed any cellular effects and no cytotoxic effects were observed. It is possible to conclude that among tested buffers, homopipes is the most suitable for studies at low pH, and may be especially useful for aluminum toxicity experiments. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Hydrogen peroxide impairs autophagic flux in a cell model of nonalcoholic fatty liver disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, Pengtao; University of Chinese Academy of Sciences, 19 Yuquan Road, Shijingshan District, Beijing 100049; Huang, Zhen

2013-04-19

Highlights: •Free fatty acids exposure induces elevated autophagy. •H{sub 2}O{sub 2} inhibits autophagic flux through impairing the fusion between autophagosomes and lysosomes. •Inhibition of autophagy potentiates H{sub 2}O{sub 2}-induced cell death. -- Abstract: Nonalcoholic fatty liver disease (NAFLD) has become the leading cause of chronic liver disease, but the pathogenesis of NAFLD is not fully clear. The aim of this study was to determine whether autophagy plays a role in the pathogenesis of NAFLD. We found that the levels of autophagy were elevated in hepatoma cells upon exposure to free fatty acids, as confirmed by the increase in the numbermore » of autophagosomes. However, exposure of hepatoma cells to H{sub 2}O{sub 2} and TNF-α, two typical “second hit” factors, increased the initiation of autophagy but inhibited the autophagic flux. The inhibition of autophagy sensitized cells to pro-apoptotic stimuli. Taken together, our results suggest that autophagy acts as a protective mechanism in the pathogenesis of NAFLD and that impairment of autophagy might induce more severe lesions of the liver. These findings will be a benefit to the understanding of the pathogenesis of NAFLD and might suggest a strategy for the prevention and cure of NAFLD.« less

Camel milk triggers apoptotic signaling pathways in human hepatoma HepG2 and breast cancer MCF7 cell lines through transcriptional mechanism.

PubMed

Korashy, Hesham M; Maayah, Zaid H; Abd-Allah, Adel R; El-Kadi, Ayman O S; Alhaider, Abdulqader A

2012-01-01

Few published studies have reported the use of crude camel milk in the treatment of stomach infections, tuberculosis and cancer. Yet, little research was conducted on the effect of camel milk on the apoptosis and oxidative stress associated with human cancer. The present study investigated the effect and the underlying mechanisms of camel milk on the proliferation of human cancer cells using an in vitro model of human hepatoma (HepG2) and human breast (MCF7) cancer cells. Our results showed that camel milk, but not bovine milk, significantly inhibited HepG2 and MCF7 cells proliferation through the activation of caspase-3 mRNA and activity levels, and the induction of death receptors in both cell lines. In addition, Camel milk enhanced the expression of oxidative stress markers, heme oxygenase-1 and reactive oxygen species production in both cells. Mechanistically, the increase in caspase-3 mRNA levels by camel milk was completely blocked by the transcriptional inhibitor, actinomycin D; implying that camel milk increased de novo RNA synthesis. Furthermore, Inhibition of the mitogen activated protein kinases differentially modulated the camel milk-induced caspase-3 mRNA levels. Taken together, camel milk inhibited HepG2 and MCF7 cells survival and proliferation through the activation of both the extrinsic and intrinsic apoptotic pathways.

Polychromatic Light (480-3400 nm) Upregulates Sensitivity of Tumor Cells to Lysis by Natural Killers.

PubMed

Knyazev, Nickolay A; Samoilova, Kira A; Abrahamse, Heidi; Filatova, Natalia A

2016-09-01

This study evaluates the participation of immunological mechanisms of downregulation of murine hepatoma cells MH22a after direct exposure to polychromatic polarized light. Previous studies have shown that exposure to a combination of visible (VIS) and infrared (IR) light leads to decreased tumorigenicity of the murine hepatoma cells MH22a, which correlated with an increase in the amount of cells with reorganized cytoskeleton in the submembrane region. The mechanism of tumor inhibition and elimination has not been determined. Polychromatic light (480-3400 nm) has been used at doses of 4.8 and 9.6 J/cm(2) to determine the sensitivity of murine MH22a cells and human erythroleukemia cells K562 exposed to this light, to lysis by effector cells of innate immunity (NK cells), and enhancement of the glycocalyx of the studied tumor cells. This was determined using flow cytometry, the H(3)-uridine cytotoxic test followed by spectrophotometry. VIS-IR light increases the sensitivity of MH-22a cells at a dose 4.8 J/cm(2) and K562 cells at 9.6 J/cm(2). The enhancement of sensitivity of tumor cells to NK lysis changed their ability to absorb alcian blue, reflecting a change in the expression of the glycocalyx. Increasing the sensitivity of the murine tumor cells MH22a and human K562 irradiated VIS-IR light correlated with a change in the expression of their glycocalyx. The results of the present study demonstrate that the reduction of tumorigenicity of irradiated tumor cells is due to their sensitivity to lysis by NK cells of the immune system.

Modulation of the human equilibrative nucleoside transporter1 (hENT1) activity by IL-4 and PMA in B cells from chronic lymphocytic leukemia.

PubMed

Fernández Calotti, Paula; Galmarini, Carlos María; Cañones, Cristian; Gamberale, Romina; Saénz, Daniel; Avalos, Julio Sánchez; Chianelli, Mónica; Rosenstein, Ruth; Giordano, Mirta

2008-02-15

Nucleoside transporters (NTs) are essential for the uptake of therapeutic nucleoside analogs, broadly used in cancer treatment. The mechanisms responsible for NT regulation are largely unknown. IL-4 is a pro-survival signal for chronic lymphocytic leukemia (CLL) cells and has been shown to confer resistance to nucleoside analogs. The aim of this study was to investigate whether IL-4 is able to modulate the expression and function of the human equilibrative NT1 (hENT1) in primary cultures of CLL cells and, consequently, to affect cytotoxicity induced by therapeutic nucleosides analogs. We found that treatment with IL-4 (20 ng/ml for 24 h) increased mRNA hENT1 expression in CLL cells without affecting that of normal B cells. Given that the enhanced mRNA levels of hENT1 in CLL cells did not result in increased transport activity, we examined the possibility that hENT1 induced by IL-4 may require post-translational modifications to become active. We found that the acute stimulation of PKC in IL-4-treated CLL cells by short-term incubation with PMA significantly increased hENT1 transport activity and favoured fludarabine-induced apoptosis. By contrast, and in line with previous reports, IL-4 plus PMA protected CLL cells from a variety of cytotoxic agents. Our findings indicate that the combined treatment with IL-4 and PMA enhances hENT1 activity and specifically sensitizes CLL cells to undergo apoptosis induced by fludarabine.

(Z)-3,5,4'-Trimethoxystilbene Limits Hepatitis C and Cancer Pathophysiology by Blocking Microtubule Dynamics and Cell Cycle Progression

PubMed Central

Nguyen, Charles B.; Kotturi, Hari; Waris, Gulam; Mohammed, Altaf; Chandrakesan, Parthasarathy; May, Randal; Sureban, Sripathi; Weygant, Nathaniel; Qu, Dongfeng; Rao, Chinthalapally V.; Dhanasekaran, Danny N.; Bronze, Michael S.; Houchen, Courtney W.; Ali, Naushad

2016-01-01

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related deaths worldwide. Chronic hepatitis C virus (HCV) infection causes induction of several tumor/cancer stem cell (CSC) markers and is known to be a major risk factor for development of HCC. Therefore, drugs that simultaneously target viral replication and CSC properties are needed for a risk-free treatment of advanced stage liver diseases including HCC. Here, we demonstrated that (Z)-3,5,4’-trimethoxystilbene (Z-TMS) exhibits potent anti-tumor and anti-HCV activities without exhibiting cytotoxicity to human hepatocytes in vitro or in mice livers. Diethylnitrosamine (DEN)/carbon tetrachloride (CCl4) extensively induced expression of DCLK1 (a CSC marker) in the livers of C57BL/6 mice following hepatic injury. Z-TMS exhibited hepatoprotective effects against DEN/CCl4-induced injury by reducing DCLK1 expression and improving histological outcomes. The drug caused bundling of DCLK1 with microtubules and blocked cell cycle progression at G2/M phase in hepatoma cells via downregulation of CDK1, induction of p21cip1/waf1 expression, and inhibition of Akt (Ser473) phosphorylation. Z-TMS also inhibited proliferation of erlotinib-resistant lung adenocarcinoma cells (H1975) bearing the T790M EGFR mutation most likely by promoting autophagy and nuclear fragmentation. In conclusion, Z-TMS appears to be a unique therapeutic agent targeting HCV and concurrently eliminating cells with neoplastic potential during chronic liver diseases including HCC. It may also be a valuable drug for targeting drug-resistant carcinomas and cancers of the lungs, pancreas, colon, and intestine in which DCLK1 is involved in tumorigenesis. PMID:27287718

B7-H4 overexpression in ovarian tumors.

PubMed

Tringler, Barbara; Liu, Wenhui; Corral, Laura; Torkko, Kathleen C; Enomoto, Takayuki; Davidson, Susan; Lucia, M Scott; Heinz, David E; Papkoff, Jackie; Shroyer, Kenneth R

2006-01-01

Despite great advances in therapeutic management, the mortality rate for ovarian cancer has remained relatively stable over the past 50 years. This study was designed to evaluate the expression of B7-H4 protein, recently identified as a potential molecular marker of breast and ovarian cancer by quantitative PCR analysis, in benign tumors, tumors of low malignant potential and malignant tumors of the ovary. Archival formalin-fixed tissue blocks from serous, mucinous, endometrioid and clear cell ovarian tumors were evaluated by immunohistochemistry for the distribution of B7-H4 expression, and staining intensity was measured by automated image analysis. Univariate analyses were used to test for statistically significant relationships. B7-H4 cytoplasmic and membranous expression was detected in all primary serous (n = 32), endometrioid (n = 12), and clear cell carcinomas (n = 15), and in all metastatic serous (n = 23) and endometrioid (n = 7) ovarian carcinomas. By contrast, focal B7-H4 expression was detected in only 1/11 mucinous carcinomas. The proportion of positive cells and median staining intensity was greater in serous carcinomas than in serous cystadenomas or serous tumors of low malignant potential, and the differences were statistically significant (P < 0.0001 and P = 0.034, respectively). The median staining intensity was also significantly greater in endometrioid carcinomas than in endometriosis (P = 0.005). The consistent overexpression of B7-H4 in serous, endometrioid and clear cell ovarian carcinomas and the relative absence of expression in most normal somatic tissues indicates that B7-H4 should be further investigated as a potential diagnostic marker or therapeutic target for ovarian cancer.

Sphingoid bases from sea cucumber induce apoptosis in human hepatoma HepG2 cells through p-AKT and DR5.

PubMed

Hossain, Zakir; Sugawara, Tatsuya; Hirata, Takashi

2013-03-01

Biofunctional marine compounds have recently received substantial attention for their nutraceutical characteristics. In this study, we investigated the apoptosis-inducing effects of sphingoid bases prepared from sea cucumber using human hepatoma HepG2 cells. Apoptotic effects were determined by cell viability assay, DNA fragmentation assay, caspase-3 and caspase-8 activities. The expression levels of apoptosis-inducing death receptor-5 (DR5) and p-AKT were assayed by western blot analysis, and mRNA expression of bax, GADD45 and PPARγ was assayed by quantitative RT-PCR analysis. Sphingoid bases from sea cucumber markedly reduced the cell viability of HepG2 cells. DNA fragmentation indicative of apoptosis was observed in a dose-dependent manner. The expression levels of the apoptosis inducer protein Bax were increased by the sphingoid bases from sea cucumber. GADD45, which plays an important role in apoptosis-inducing pathways, was markedly upregulated by sphingoid bases from sea cucumber. Upregulation of PPARγ mRNA was also observed during apoptosis induced by the sphingoid bases. The expression levels of DR5 and p-AKT proteins were increased and decreased, respectively, as a result of the effects of sphingoid bases from sea cucumber. The results indicate that sphingoid bases from sea cucumber induce apoptosis in HepG2 cells through upregulation of DR5, Bax, GADD45 and PPARγ and downregulation of p-AKT. Our results show for the first time the functional properties of marine sphingoid bases as inducers of apoptosis in HepG2 cells.

Regulation of intracellular pH in LLC-PK1 cells by Na+/H+ exchange.

PubMed

Montrose, M H; Murer, H

1986-01-01

Suspensions of LLC-PK1 cells (a continuous epitheliod cell line with renal characteristics) are examined for mechanisms of intracellular pH regulation using the fluorescent probe BCECF. Initial experiments determine suitable calibration procedures for use of the BCECF fluorescent signal. They also determine that the cell suspension contains cells which (after 4 hr in suspension) have Na+ and K+ gradients comparable to those of cells in monolayer culture. The steady-state intracellular pH (7.05 +/- 0.01, n = 5) of cells which have recovered in (pH 7.4) Na+-containing medium is not affected over several minutes by addition of 100 microM amiloride or removal of extracellular Na+ (Na+o less than 1 mM). In contrast, when the cells recover from an acid load (caused by NH4 preincubation and removal), the recovery is largely Na+ dependent and is sensitive to 100 microM amiloride. These results suggest that with resting pH near neutrality, both Na+o/H+i and Na+i/H+o exchange reactions are functionally inactive (compared to cellular buffering capacity). In contrast, Na+o/H+i exchange is activated by an increased cellular acid load. This activation may be observed directly either as a stimulation of net H+ efflux or net Na+ influx with decreasing intracellular pH. The extrapolation of this latter data suggests a "set point" of Na+/H+ exchange of approximately pH 7.0, consistent with the observed resting intracellular pH of approximately 7.05.

B7-H4 expression is correlated with tumor progression and clinical outcome in urothelial cell carcinoma.

PubMed

Fan, Min; Zhuang, Qianfeng; Chen, Yiming; Ding, Tao; Yao, Hongwei; Chen, Lujun; He, Xiaozhou; Xu, Xianlin

2014-01-01

To investigate the mRNA and protein levels of B7-H4, a B7 family molecule, in human urothelial cell carcinoma (UCC), to analyze the relationship between B7-H4 protein expression level and pathological stage of UCC, and to examine the potential of B7-H4 as a prognostic factor in UCC. mRNA and protein levels of B7-H4 were measured in pairs of tumor tissues and matched adjacent nontumor tissue obtained from patients with UCC by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunohistochemical staining, respectively. Association of the protein level of B7-H4 with pathological tumor stage and the overall survival of UCC patients were also analyzed. B7-H4 mRNA and protein level were significantly higher in UCC tumor tissues compared with adjacent nontumor tissues as assessed by qRT-PCR and immunohistochemical staining, respectively. Higher B7-H4 protein levels were observed in patients with more advanced pathological stage of UCC and were also associated with decreased overall survival of patients with UCC. The findings from this study indicate that B7-H4 has the potential to be an independent prognostic indicator for UCC.

Identification of epitopes recognised by mucosal CD4(+) T-cell populations from cattle experimentally colonised with Escherichia coli O157:H7.

PubMed

Corbishley, Alexander; Connelley, Timothy K; Wolfson, Eliza B; Ballingall, Keith; Beckett, Amy E; Gally, David L; McNeilly, Tom N

2016-09-02

Vaccines targeting enterohaemorrhagic Escherichia coli (EHEC) O157:H7 shedding in cattle are only partially protective. The correlates of protection of these vaccines are unknown, but it is probable that they reduce bacterial adherence at the mucosal surface via the induction of blocking antibodies. Recent studies have indicated a role for cellular immunity in cattle during colonisation, providing an impetus to understand the bacterial epitopes recognised during this response. This study mapped the epitopes of 16 EHEC O157:H7 proteins recognised by rectal lymph node CD4(+) T-cells from calves colonised with Shiga toxin producing EHEC O157:H7 strains. 20 CD4(+) T-cell epitopes specific to E. coli from 7 of the proteins were identified. The highly conserved N-terminal region of Intimin, including the signal peptide, was consistently recognised by mucosal CD4(+) T-cell populations from multiple animals of different major histocompatibility complex class II haplotypes. These T-cell epitopes are missing from many Intimin constructs used in published vaccine trials, but are relatively conserved across a range of EHEC serotypes, offering the potential to develop cross protective vaccines. Antibodies recognising H7 flagellin have been consistently identified in colonised calves; however CD4(+) T-cell epitopes from H7 flagellin were not identified in this study, suggesting that H7 flagellin may act as a T-cell independent antigen. This is the first time that the epitopes recognised by CD4(+) T-cells following colonisation with an attaching and effacing pathogen have been characterised in any species. The findings have implications for the design of antigens used in the next generation of EHEC O157:H7 vaccines.

A highly selective fluorescent probe based on coumarin for the imaging of N2H4 in living cells

NASA Astrophysics Data System (ADS)

Chen, Song; Hou, Peng; Wang, Jing; Liu, Lei; Zhang, Qi

2017-02-01

A turn-on fluorescence probe for highly sensitive and selective detection of N2H4 was developed based on hydrazine-triggered a substitution- cyclization-elimination cascade. Upon the treatment with N2H4, probe 1, 4-methyl-coumarin-7-yl bromobutanoate, displayed a remarkable fluorescence enhancement (25-fold) with a maximum at 450 nm. This probe can quantitatively detect N2H4 with a extremely low detection limit as 7 × 10- 8 M. Moreover, cell imaging experiments have indicated that probe 1 has potential ability to detect and image N2H4 in biological systems.

In vitro effect of 4-nonylphenol on human chorionic gonadotropin (hCG) stimulated hormone secretion, cell viability and reactive oxygen species generation in mice Leydig cells.

PubMed

Jambor, Tomáš; Tvrdá, Eva; Tušimová, Eva; Kováčik, Anton; Bistáková, Jana; Forgács, Zsolt; Lukáč, Norbert

2017-03-01

Nonylphenol is considered an endocrine disruptor and has been reported to affect male reproductive functions. In our in vitro study, we evaluated the effects of 4-nonylphenol (4-NP) on cholesterol levels, hormone formation and viability in cultured Leydig cells from adult ICR male mice. We also determined the potential impact of 4-NP on generation of reactive oxygen species (ROS) after 44 h of cultivation. The cells were cultured with addition of 0.04; 0.2; 1.0; 2.5 and 5.0 μg/mL of 4-NP in the present of 1 IU/mL human chorionic gonadotropin (hCG) and compared to the control. The quantity of cholesterol was determined from culture medium using photometry. Determination of hormone production was performed by enzyme-linked immunosorbent assay. Metabolic activity assay was used for quantification of cell viability. The chemiluminescence technique, which uses a luminometer to measure reactive oxygen species, was employed. Applied doses of 4-NP (0.04-5.0 μg/mL) slight increase cholesterol levels and decrease production of dehydroepiandrosterone after 44 h of cultivation, but not significantly. Incubation of 4-NP treated cells with hCG significantly (P < 0.001) inhibited androstenedione, but not testosterone, formation at the highest concentration (5.0 μg/mL). The viability was significantly (P < 0.05); (P < 0.001) increased at 1.0; 2.5 and 5.0 μg/mL of 4-NP after 44 h treatment. Furthermore, 44 h treatment of 4-NP (0.04-5.0 μg/mL) caused significant (P < 0.001) intracellular accumulation of ROS in exposed cells. Taken together, the results of our in vitro study reported herein is consistent with the conclusion that 4-nonylphenol is able to influence hormonal profile, cell viability and generate ROS. Copyright © 2017 Elsevier Ltd. All rights reserved.

The hSK4 (KCNN4) isoform is the Ca2+-activated K+ channel (Gardos channel) in human red blood cells.

PubMed

Hoffman, Joseph F; Joiner, William; Nehrke, Keith; Potapova, Olga; Foye, Kristen; Wickrema, Amittha

2003-06-10

The question is, does the isoform hSK4, also designated KCNN4, represent the small conductance, Ca2+-activated K+ channel (Gardos channel) in human red blood cells? We have analyzed human reticulocyte RNA by RT-PCR, and, of the four isoforms of SK channels known, only SK4 was found. Northern blot analysis of purified and synchronously growing human erythroid progenitor cells, differentiating from erythroblasts to reticulocytes, again showed only the presence of SK4. Western blot analysis, with an anti-SK4 antibody, showed that human erythroid progenitor cells and, importantly, mature human red blood cell ghost membranes, both expressed the SK4 protein. The Gardos channel is known to turn on, given inside Ca2+, in the presence but not the absence of external Ko+ and remains refractory to Ko+ added after exposure to inside Ca2+. Heterologously expressed SK4, but not SK3, also shows this behavior. In inside-out patches of red cell membranes, the open probability (Po) of the Gardos channel is markedly reduced when the temperature is raised from 27 to 37 degrees C. Net K+ efflux of intact red cells is also reduced by increasing temperature, as are the Po values of inside-out patches of Chinese hamster ovary cells expressing SK4 (but not SK3). Thus the envelope of evidence indicates that SK4 is the gene that codes for the Gardos channel in human red blood cells. This channel is important pathophysiologically, because it represents the major pathway for cell shrinkage via KCl and water loss that occurs in sickle cell disease.

All-electron molecular Dirac-Hartree-Fock calculations: The group 4 tetrahydrides CH4, SiH4, GeH4, SnH4 and PbH4

NASA Technical Reports Server (NTRS)

Dyall, Kenneth G.; Taylor, Peter R.; Faegri, Knut, Jr.; Partridge, Harry

1990-01-01

A basis-set-expansion Dirac-Hartree-Fock program for molecules is described. Bond lengths and harmonic frequencies are presented for the ground states of the group 4 tetrahydrides, CH4, SiH4, GeH4, SnH4, and PbH4. The results are compared with relativistic effective core potential (RECP) calculations, first-order perturbation theory (PT) calculations and with experimental data. The bond lengths are well predicted by first-order perturbation theory for all molecules, but non of the RECP's considered provides a consistent prediction. Perturbation theory overestimates the relativistic correction to the harmonic frequencies; the RECP calculations underestimate the correction.

SMYD5 regulates H4K20me3-marked heterochromatin to safeguard ES cell self-renewal and prevent spurious differentiation.

PubMed

Kidder, Benjamin L; Hu, Gangqing; Cui, Kairong; Zhao, Keji

2017-01-01

Epigenetic regulation of chromatin states is thought to control the self-renewal and differentiation of embryonic stem (ES) cells. However, the roles of repressive histone modifications such as trimethylated histone 4 lysine 20 (H4K20me3) in pluripotency and development are largely unknown. Here, we show that the histone lysine methyltransferase SMYD5 mediates H4K20me3 at heterochromatin regions. Depletion of SMYD5 leads to compromised self-renewal, including dysregulated expression of OCT4 targets, and perturbed differentiation. SMYD5-bound regions are enriched with repetitive DNA elements. Knockdown of SMYD5 results in a global decrease of H4K20me3 levels, a redistribution of heterochromatin constituents including H3K9me3/2, G9a, and HP1α, and de-repression of endogenous retroelements. A loss of SMYD5-dependent silencing of heterochromatin nearby genic regions leads to upregulated expression of lineage-specific genes, thus contributing to the decreased self-renewal and perturbed differentiation of SMYD5-depleted ES cells. Altogether, these findings implicate a role for SMYD5 in regulating ES cell self-renewal and H4K20me3-marked heterochromatin.

Escherichia coli Heat-Stable Enterotoxin Mediates Na+/H+ Exchanger 4 Inhibition Involving cAMP in T84 Human Intestinal Epithelial Cells

PubMed Central

Beltrán, Ana R.; Carraro-Lacroix, Luciene R.; Bezerra, Camila N. A.; Cornejo, Marcelo; Norambuena, Katrina; Toledo, Fernando; Araos, Joaquín; Pardo, Fabián; Leiva, Andrea; Sanhueza, Carlos; Malnic, Gerhard; Sobrevia, Luis; Ramírez, Marco A.

2015-01-01

The enterotoxigenic Escherichia coli strains lead to diarrhoea in humans due to heat-labile and heat-stable (STa) enterotoxins. STa increases Cl-release in intestinal cells, including the human colonic carcinoma T84 cell line, involving increased cGMP and membrane alkalization due to reduced Na+/H+ exchangers (NHEs) activity. Since NHEs modulate intracellular pH (pHi), and NHE1, NHE2, and NHE4 are expressed in T84 cells, we characterized the STa role as modulator of these exchangers. pHi was assayed by the NH4Cl pulse technique and measured by fluorescence microscopy in BCECF–preloaded cells. pHi recovery rate (dpHi/dt) was determined in the absence or presence of 0.25 μmol/L STa (30 minutes), 25 μmol/L HOE-694 (concentration inhibiting NHE1 and NHE2), 500 μmol/L sodium nitroprusside (SNP, spontaneous nitric oxide donor), 100 μmol/L dibutyryl cyclic GMP (db-cGMP), 100 nmol/L H89 (protein kinase A inhibitor), or 10 μmol/L forskolin (adenylyl cyclase activator). cGMP and cAMP were measured in cell extracts by radioimmunoassay, and buffering capacity (ßi) and H+ efflux (J H +) was determined. NHE4 protein abundance was determined by western blotting. STa and HOE-694 caused comparable reduction in dpHi/dt and J H + (~63%), without altering basal pHi (range 7.144–7.172). STa did not alter ßi value in a range of 1.6 pHi units. The dpHi/dt and J H + was almost abolished (~94% inhibition) by STa + HOE-694. STa effect was unaltered by db-cGMP or SNP. However, STa and forskolin increased cAMP level. STa–decreased dpHi/dt and J H + was mimicked by forskolin, and STa + HOE-694 effect was abolished by H89. Thus, incubation of T84 cells with STa results in reduced NHE4 activity leading to a lower capacity of pHi recovery requiring cAMP, but not cGMP. STa effect results in a causal phenomenon (STa/increased cAMP/increased PKA activity/reduced NHE4 activity) ending with intracellular acidification that could have consequences in the gastrointestinal cells function

Analysis of regulatory mechanisms of an insulin-inducible SHARP-2 gene by (S)-Equol.

PubMed

Haneishi, Ayumi; Takagi, Katsuhiro; Asano, Kosuke; Yamamoto, Taichi; Tanaka, Takashi; Nakamura, Soichiro; Noguchi, Tamio; Yamada, Kazuya

2012-09-01

Small compounds that activate the insulin-dependent signaling pathway have potential therapeutic applications in controlling type 2 diabetes mellitus. The rat enhancer of split- and hairy-related protein-2 (SHARP-2) is an insulin-inducible transcription factor that decreases expression of the phosphoenolpyruvate carboxykinase gene, a gluconeogenic enzyme gene. In this study, we screened for soybean isoflavones that can induce the rat SHARP-2 gene expression and analyzed their mechanism(s). Genistein and (S)-Equol, a metabolite of daidzein, induced rat SHARP-2 gene expression in H4IIE rat hepatoma cells. The (S)-Equol induction was mediated by both the phosphoinositide 3-kinase- and protein kinase C (PKC)-pathways. When a dominant negative form of atypical PKC lambda (aPKCλ) was expressed, the induction of SHARP-2 mRNA level by (S)-Equol was inhibited. In addition, Western blot analyses showed that (S)-Equol rapidly activated both aPKCλ and classical PKC alpha. Furthermore, the (S)-Equol induction was inhibited by treatment with a RNA polymerase inhibitor or a protein synthesis inhibitor. Finally, a reporter gene assay revealed that the transcriptional stimulation by (S)-Equol was mediated by nucleotide sequences located between -4687 and -4133 of the rat SHARP-2 gene. Thus, we conclude that (S)-Equol is an useful dietary supplement to control type 2 diabetes mellitus. Copyright © 2012 Elsevier Inc. All rights reserved.

Down regulation of ITGA4 and ITGA5 genes after formation of 3D spherules by human Wharton's jelly stem cells (hWJSCs).

PubMed

Mostafavi-Pour, Zohreh; Ashrafi, Mohammad Reza; Talaei-Khozani, Tahereh

2018-06-01

Human Wharton's jelly mesenchymal stem cells (hWJSCs) are multipotent stem cells that could be aggregated into 3D spherules. ITGA4 and ITGA5 genes encode α4 and α5 subunits of integrins, respectively. In this study, we analyzed expression levels of ITGA4 and ITGA5 gene mRNAs in undifferentiated and 3D spherules forming hWJSCs in order to determine their expression pattern for possible future treatment of cancer cells in a co-culture fashion. For the purpose of obtaining hWJSCs, umbilical cords were collected from patients with caesarian section at full term delivery. The cells were then characterized according to cell surface markers using flow cytometry. Furthermore pluripotency of the obtained cells was verified. Subsequently the cells were aggregated in 3D spherules using hanging drop cultures. Expression levels of ITGA4 and ITGA5 gene mRNAs were determined by RT-PCR and Real time PCR, both in the initial undifferentiated cells and those aggregated in the spherules. The obtained hWJSCs demonstrated pluripotency, differentiating to adipogenic and osteogenic cells. They also expressed mesenchymal stem cell surface markers. Following the aggregation of these cells and formation of 3D spherules, mRNA expression levels of both genes were significantly reduced (P < 0.05) compared with the initial undifferentiated state. The results of this study demonstrated that aggregation of hWJSCs into spherules alters their expression of ITGA4 and ITGA5. The implications of such an alteration would require further research.

Progression of conventional hepatic cell culture models to bioengineered HepG2 cells for evaluation of herbal bioactivities.

PubMed

Kaur, Pardeep; Robin; Mehta, Rajendra G; Arora, Saroj; Singh, Balbir

2018-06-01

Cancer cell lines of human tissue origin have been extensively used to investigate antiproliferative activity and toxicity of herbal extracts, isolated compounds, and anticancer drugs. These cell lines are genetically and/or epigenetically well characterized to determine the altered expression of proteins within given cellular pathways and critical genes in cancer. Human derived hepatoma (HepG2) cell line has been extensively exploited to examine cytoprotective, antioxidative, hepatoprotective, anti-hepatoma, hypocholesterolemic, anti-steatosis, bioenergetic homeostatic and anti-insulin resistant properties. Moreover, mechanism of action of various botanicals and bioactive constituents has been reported using these cells. HepG2 cells have significant differences as compared to primary hepatocytes with respect to expression of cytochrome P450 enzymes and xenobiotic receptors in conventional in vitro culture conditions. Therefore, strategies have been employed to overcome limitations of two dimensional (2D) in vitro HepG2 cell culture in order to recognize functional biomarkers more accurately and to boost its predictive value in clinical research. In consequence, three dimensional (3D) human hepatoma cell culture models are being developed as a resource to achieve these goals of simulating the in vivo tumor microenvironment. It is assumed that bioengineered 3D hepatoma cell culture models can provide significant assistance in scrutinizing the molecular response of herbal natural products to recognize novel prognostic targets and crucial biomarkers in treatment strategies for cancer patients in near future.

H3K4 demethylase activities repress proliferative and postmitotic aging

PubMed Central

Alvares, Stacy M; Mayberry, Gaea A; Joyner, Ebony Y; Lakowski, Bernard; Ahmed, Shawn

2014-01-01

Homeostasis of postmitotic and proliferating cells is maintained by pathways that repress stress. We found that the Caenorhabditis elegans histone 3 lysine 4 (H3K4) demethylases RBR-2 and SPR-5 promoted postmitotic longevity of stress-resistant daf-2 adults, altered pools of methylated H3K4, and promoted silencing of some daf-2 target genes. In addition, RBR-2 and SPR-5 were required for germ cell immortality at a high temperature. Transgenerational proliferative aging was enhanced for spr-5; rbr-2 double mutants, suggesting that these histone demethylases may function sequentially to promote germ cell immortality by targeting distinct H3K4 methyl marks. RBR-2 did not play a comparable role in the maintenance of quiescent germ cells in dauer larvae, implying that it represses stress that occurs as a consequence of germ cell proliferation, rather than stress that accumulates in nondividing cells. We propose that H3K4 demethylase activities promote the maintenance of chromatin states during stressful growth conditions, thereby repressing postmitotic aging of somatic cells as well as proliferative aging of germ cells. PMID:24134677

Synthesis and antitumor screening of new 1,7-diphenyl-3-(1,3-disubstituted-1H-pyrazole-4-carbonyl)-[1,2,4]triazolo[4,3-a]pyrimidin-5(1H)-ones.

PubMed

Shawali, Ahmad S; Sherif, Sherif M; Darwish, Manal A A; El-merzabani, Mahmoud M

2010-01-01

A new series of 3-(1,3-disubstituted-1H-pyrazole-4-carbonyl)-1,7-diphenyl-[1,2,4]triazolo[4,3-a]pyrimidin-5(1H)-ones 4 was prepared by reaction of the enaminone 2 with hydrazonoyl halides 3. The preliminary screening for antitumor activity of the synthesized compounds was carried out against Ehrlich Ascites Carcinoma tumor cells. The results revealed that the studied compounds 4 have low or no antitumor activity towards EAC tumor cells.

In vitro responses to avian influenza H5 by human CD4 T-cells*

PubMed Central

Cusick, Matthew F; Wang, Shuping; Eckels, David D

2009-01-01

To address the question of whether human T-cells are capable of recognizing novel isolates of influenza virus, in vitro responses to recombinant antigens and synthetic peptides derived from the sequences of H1, H3, and H5 were examined in a cohort of 64 individuals selected from a healthy blood donor population. Humans respond in vitro to H1 and H3 following exposure through natural infection and vaccination. Responses to H5 were well correlated with those to H1 or H3 and thus a significant repertoire of H5-responsive T-cells is present in many individuals; clear non-responders to H1, H3, and H5, however, do exist. Differences were observed in the cytokine responses to H1, H3, and H5; whereas both IL-2 and IFN-γ production characteristic of memory responses were observed for H1 and H3, H5-specific responses elicited primarily IL-2 and little or no IFN-γ consistent with a naïve T cell phenotype. Responses to all influenza HA were restricted by HLA-DR molecules. To address the structural basis for T-cell recognition of H1 and H5, overlapping synthetic peptides were used to identify epitopes and to determine whether recognition of H5 was limited to homologous sequences in H1, the most closely related HA phylogenetically. Although responses were generally correlated, no complete structural overlap was observed. These results suggest that helper T cell cross reactivity between different influenza strains may impart cross-protection to H5N1 strain of influenza. PMID:19841175

Antitumor effect of the integrin α4 signaling inhibitor JK273 in non-small cell lung cancer NCI-H460 cells.

PubMed

Lu, Thien Nhan; Ganganna, Bogonda; Pham, Thuy Trang; Vo, Anh Van; Lu, Thien Phuc; Nguyen, Huong-Giang Thi; Nguyen, My-Nuong Thi; Huynh, Phuong Nguyen; Truong, Ngoc Tuyen; Lee, Jongkook

2017-09-16

Lung cancer accounts for the highest death rate among cancers worldwide, with most patients being diagnosed with non-small cell lung cancer (NSCLC), urging more effective therapies. We report that JK273, a pyrrolo[2,3-d]pyrimidine analog, which inhibits α4 integrin signaling, showed a selective cytotoxic effect against HCI-H460 NSCLC cells, with an IC 50 of 0.98 ± 0.15 μM, but showed less sensitivity to fibroblasts with a selectivity index (SI) greater than 30. This effect was attributed to cell cycle arrest at S phase by JK273 treatment, resulting in the apoptosis of NCI-H460 cells, further confirmed by exposing phosphatidylserine and morphological changes. Taken together with the previous study of JK273 inhibiting cell migration, we propose that JK273 could serve as an antitumor compound to specifically target cancer cells but not non-cancerous cells by triggering programmed cell death, in addition to anti-metastatic effects in cancer therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

The tuberculosis vaccine H4:IC31 is safe and induces a persistent polyfunctional CD4 T cell response in South African adults: A randomized controlled trial.

PubMed

Geldenhuys, Hennie; Mearns, Helen; Miles, David J C; Tameris, Michele; Hokey, David; Shi, Zhongkai; Bennett, Sean; Andersen, Peter; Kromann, Ingrid; Hoff, Søren T; Hanekom, Willem A; Mahomed, Hassan; Hatherill, Mark; Scriba, Thomas J; van Rooyen, Michele; Bruce McClain, J; Ryall, Robert; de Bruyn, Guy

2015-07-09

New, more effective vaccines to prevent tuberculosis (TB) disease are needed urgently. H4:IC31 is an investigational vaccine that contains a fusion protein of the immunodominant antigens TB10.4 and Ag85B, formulated in IC31 adjuvant. We assessed the safety and immunogenicity of H4:IC31 in South African adults from a TB endemic setting. In this double blind, placebo controlled, phase I trial, Mycobacterium tuberculosis-uninfected, HIV-uninfected, healthy adults with a history of childhood BCG vaccination were randomly allocated to two intramuscular vaccinations with 5, 15, 50 or 150 μg H4 formulated in 500nmol IC31, two months apart. Vaccinees were followed for six months to assess safety; immunogenicity was measured by ELISpot and intracellular cytokine staining assays. Thirty-two participants received H4:IC31 and 8 received placebo. Injection site adverse events were common but mild; mild fatigue was the most common systemic adverse event. Frequencies of adverse events did not differ between dosage groups. Detectable antigen-specific CD4 T cell responses were induced by all doses of H4:IC31, but doses below 50 μg induced the highest frequencies of CD4 T cells, comprised predominantly of IFN-γ(+)TNF-α(+)IL-2(+) or TNF-α(+)IL-2(+) cells. These memory responses persisted up to the end of follow up, on study day 182. H4:IC31 demonstrated an acceptable safety profile and was immunogenic in South African adults. In this trial, the 15 μg dose appeared to induce the most optimal immune response. Copyright © 2015 Elsevier Ltd. All rights reserved.

Trout hepatoma--a preliminary report

USGS Publications Warehouse

Rucker, R.R.; Yasutake, W.T.; Wolf, H.

1961-01-01

Fish pathology and its role in fish culture were brought into prominence in the spring of 1960 by the disclosure of a high incidence of hepatomas in hatchery-reared rainbow trout. The current problem came to light as the result of a routine inspection of live trout shipments at a California border fish-disease checking station. This service is performed by personnel of the California Department of Fish and Game to preclude the introduction or further spread of communicable fish diseases into California watersheds. Collaborative studies which followed revealed the nationwide distribution of the disease. This unusual disease soon attracted the attention of the Bureau of Sport Fisheries and Wildlife, the Food and Drug Administration, Public Health Service, and several western State health and conservation agencies.

Recombinant interleukin-12 and interleukin-18 antitumor therapy in a guinea-pig hepatoma cell implant model.

PubMed

Shiratori, Ikuo; Suzuki, Yasuhiko; Oshiumi, Hiroyuki; Begum, Nasim A; Ebihara, Takashi; Matsumoto, Misako; Hazeki, Kaoru; Kodama, Ken; Kashiwazaki, Yasuo; Seya, Tsukasa

2007-12-01

Interleukin (IL)-12 and IL-18 are secreted by myeloid cells activated with adjuvants such as Bacillus Calmette-Guérin (BCG) cell wall. They induce T-helper 1 polarization in the host immune system and upregulate production of lymphocyte interferon-gamma, which leads to the induction of an antitumor gene program. It has been reported that humans have an immune system that more closely resembles that of the guinea pig in adjuvant-response features rather than the mouse system, which prevents the mouse results being extrapolated to human immunotherapy. Here we have constructed a tumor-implant system in guinea pigs to evaluate the antitumor potential of guinea pig IL-12 (gpIL-12) and guinea pig IL-18 (gpIL-18). Purified recombinant gpIL-12 and gpIL-18 were prepared and applied intraperitoneally to tumor-bearing (line 10 hepatoma) guinea pigs as the basis of the adjuvant immunotherapy. Intraperitoneal administration of gpIL-12 and gpIL-18 led to retardation of primary tumor growth and suppression of lymph-node metastasis in tumor-bearing guinea pigs. The permissible range of IL-12 appeared wider in guinea pigs than in mice. Even at an IL-12 dose higher than that in mice, there was no evidence of side-effects until day 26, when the guinea pigs were killed. gpIL-18 augmented the antitumor effect of gpIL-12 but exerted less ability to suppress lymph-node metastasis. The effects of gpIL-12 and gpIL-18 on the tumors implanted in guinea pigs will encourage us to use IL-12- and IL-18-inducible adjuvants for immunotherapy in human patients with solid cancer.

Virulence from vesicles: Novel mechanisms of host cell injury by Escherichia coli O104:H4 outbreak strain.

PubMed

Kunsmann, Lisa; Rüter, Christian; Bauwens, Andreas; Greune, Lilo; Glüder, Malte; Kemper, Björn; Fruth, Angelika; Wai, Sun Nyunt; He, Xiaohua; Lloubes, Roland; Schmidt, M Alexander; Dobrindt, Ulrich; Mellmann, Alexander; Karch, Helge; Bielaszewska, Martina

2015-08-18

The highly virulent Escherichia coli O104:H4 that caused the large 2011 outbreak of diarrhoea and haemolytic uraemic syndrome secretes blended virulence factors of enterohaemorrhagic and enteroaggregative E. coli, but their secretion pathways are unknown. We demonstrate that the outbreak strain releases a cocktail of virulence factors via outer membrane vesicles (OMVs) shed during growth. The OMVs contain Shiga toxin (Stx) 2a, the major virulence factor of the strain, Shigella enterotoxin 1, H4 flagellin, and O104 lipopolysaccharide. The OMVs bind to and are internalised by human intestinal epithelial cells via dynamin-dependent and Stx2a-independent endocytosis, deliver the OMV-associated virulence factors intracellularly and induce caspase-9-mediated apoptosis and interleukin-8 secretion. Stx2a is the key OMV component responsible for the cytotoxicity, whereas flagellin and lipopolysaccharide are the major interleukin-8 inducers. The OMVs represent novel ways for the E. coli O104:H4 outbreak strain to deliver pathogenic cargoes and injure host cells.

Clinical and biological significance of hepatoma-derived growth factor in Ewing's sarcoma.

PubMed

Yang, Yang; Li, Hui; Zhang, Fenfen; Shi, Huijuan; Zhen, Tiantian; Dai, Sujuan; Kang, Lili; Liang, Yingjie; Wang, Jin; Han, Anjia

2013-11-01

We sought to investigate the clinicopathological significance and biological function of hepatoma-derived growth factor (HDGF) in Ewing's sarcoma. Our results showed that HDGF expression is up-regulated in Ewing's sarcoma. Nuclear HDGF expression is significantly associated with tumour volume (p < 0.001), metastases at diagnosis (p < 0.001), low overall survival rate (p < 0.001) and low disease-free survival rate (p < 0.001). HDGF knock-down results in significant reduction of Ewing's sarcoma cell growth, proliferation and enhances tumourigenesis, both in vitro and in vivo. Meanwhile, HDGF knock-down causes cell cycle arrest and enhanced sensitization to serum starvation-induced apoptosis. Furthermore, recombinant HDGF promotes proliferation and colony formation of Ewing's sarcoma cells. Ninety-eight candidate HDGF downstream genes were identified in Ewing's sarcoma cells using cDNA microarray analysis. In addition, we found that HDGF knock-down inhibited FLI1 expression in Ewing's sarcoma cells at the mRNA and protein levels. Our findings suggest that HDGF exhibits oncogenic properties and may be a novel prognostic factor in Ewing's sarcoma. Targeting HDGF might be a potential therapeutic strategy for Ewing's sarcoma. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Anti-hepatoma activity and mechanism of corn silk polysaccharides in H22 tumor-bearing mice.

PubMed

Yang, Jingyue; Li, Xiao; Xue, Yan; Wang, Nan; Liu, Wenchao

2014-03-01

Corn silk is a well known traditional Chinese herbal medicine and corn silk polysaccharides (CSP) possess multiple pharmacological activities. However, the antitumor effect of CSP on hepatocarcinoma has not been studied. This study aimed to investigate the effects of CSP on tumor growth and immune functions in H22 hepatocarcinoma tumor-bearing mice. The results demonstrated that CSP could not only inhibit the tumor growth, but also extended the survival time of H22 tumor-bearing mice. Besides, CSP administration could increase the body weight, peripheral white blood cells (WBC) count, thymus index and spleen index of H22 tumor-bearing mice. Furthermore, the production of serum cytokines in H22 tumor-bearing mice, such as IL-2, IL-6 and TNF-α, was enhanced by CSP treatment. In addition, no toxicological effects were observed on hepatic function and renal function in CSP-treated mice transplanted H22 tumor cells. In summary, this experimental finding indicated that CSP could elevate the immune functions in H22 tumor-bearing mice to enhance its antitumor activity and CSP seems to be a safe and effective agent for the treatment of hepatocellular carcinoma. Copyright © 2013 Elsevier B.V. All rights reserved.

Trans-tail regulation of MLL4-catalyzed H3K4 methylation by H4R3 symmetric dimethylation is mediated by a tandem PHD of MLL4

PubMed Central

Dhar, Shilpa S.; Lee, Sung-Hun; Kan, Pu-Yeh; Voigt, Philipp; Ma, Li; Shi, Xiaobing; Reinberg, Danny; Lee, Min Gyu

2012-01-01

Mixed-lineage leukemia 4 (MLL4; also called MLL2 and ALR) enzymatically generates trimethylated histone H3 Lys 4 (H3K4me3), a hallmark of gene activation. However, how MLL4-deposited H3K4me3 interplays with other histone marks in epigenetic processes remains largely unknown. Here, we show that MLL4 plays an essential role in differentiating NT2/D1 stem cells by activating differentiation-specific genes. A tandem plant homeodomain (PHD4–6) of MLL4 recognizes unmethylated or asymmetrically dimethylated histone H4 Arg 3 (H4R3me0 or H4R3me2a) and is required for MLL4's nucleosomal methyltransferase activity and MLL4-mediated differentiation. Kabuki syndrome mutations in PHD4–6 reduce PHD4–6's binding ability and MLL4's catalytic activity. PHD4–6's binding strength is inhibited by H4R3 symmetric dimethylation (H4R3me2s), a gene-repressive mark. The protein arginine methyltransferase 7 (PRMT7), but not PRMT5, represses MLL4 target genes by up-regulating H4R3me2s levels and antagonizes MLL4-mediated differentiation. Consistently, PRMT7 knockdown increases MLL4-catalyzed H3K4me3 levels. During differentiation, decreased H4R3me2s levels are associated with increased H3K4me3 levels at a cohort of genes, including many HOXA and HOXB genes. These findings indicate that the trans-tail inhibition of MLL4-generated H3K4me3 by PRMT7-regulated H4R3me2s may result from H4R3me2s's interference with PHD4–6's binding activity and is a novel epigenetic mechanism that underlies opposing effects of MLL4 and PRMT7 on cellular differentiation. PMID:23249737

Trans-tail regulation of MLL4-catalyzed H3K4 methylation by H4R3 symmetric dimethylation is mediated by a tandem PHD of MLL4.

PubMed

Dhar, Shilpa S; Lee, Sung-Hun; Kan, Pu-Yeh; Voigt, Philipp; Ma, Li; Shi, Xiaobing; Reinberg, Danny; Lee, Min Gyu

2012-12-15

Mixed-lineage leukemia 4 (MLL4; also called MLL2 and ALR) enzymatically generates trimethylated histone H3 Lys 4 (H3K4me3), a hallmark of gene activation. However, how MLL4-deposited H3K4me3 interplays with other histone marks in epigenetic processes remains largely unknown. Here, we show that MLL4 plays an essential role in differentiating NT2/D1 stem cells by activating differentiation-specific genes. A tandem plant homeodomain (PHD(4-6)) of MLL4 recognizes unmethylated or asymmetrically dimethylated histone H4 Arg 3 (H4R3me0 or H4R3me2a) and is required for MLL4's nucleosomal methyltransferase activity and MLL4-mediated differentiation. Kabuki syndrome mutations in PHD(4-6) reduce PHD(4-6)'s binding ability and MLL4's catalytic activity. PHD(4-6)'s binding strength is inhibited by H4R3 symmetric dimethylation (H4R3me2s), a gene-repressive mark. The protein arginine methyltransferase 7 (PRMT7), but not PRMT5, represses MLL4 target genes by up-regulating H4R3me2s levels and antagonizes MLL4-mediated differentiation. Consistently, PRMT7 knockdown increases MLL4-catalyzed H3K4me3 levels. During differentiation, decreased H4R3me2s levels are associated with increased H3K4me3 levels at a cohort of genes, including many HOXA and HOXB genes. These findings indicate that the trans-tail inhibition of MLL4-generated H3K4me3 by PRMT7-regulated H4R3me2s may result from H4R3me2s's interference with PHD(4-6)'s binding activity and is a novel epigenetic mechanism that underlies opposing effects of MLL4 and PRMT7 on cellular differentiation.

All-electron molecular Dirac-Hartree-Fock calculations - The group IV tetrahydrides CH4, SiH4, GeH4, SnH4, and PbH4

NASA Technical Reports Server (NTRS)

Dyall, Kenneth G.; Taylor, Peter R.; Faegri, Knut, Jr.; Partridge, Harry

1991-01-01

A basis-set-expansion Dirac-Hartree-Fock program for molecules is described. Bond lengths and harmonic frequencies are presented for the ground states of the group 4 tetrahydrides, CH4, SiH4, GeH4, SnH4, and PbH4. The results are compared with relativistic effective core potential (RECP) calculations, first-order perturbation theory (PT) calculations and with experimental data. The bond lengths are well predicted by first-order perturbation theory for all molecules, but none of the RECP's considered provides a consistent prediction. Perturbation theory overestimates the relativistic correction to the harmonic frequencies; the RECP calculations underestimate the correction.

CD4+ T Cells Reactive to Enteric Bacterial Antigens in Spontaneously Colitic C3H/HeJBir Mice: Increased T Helper Cell Type 1 Response and Ability to Transfer Disease

PubMed Central

Cong, Yingzi; Brandwein, Steven L.; McCabe, Robert P.; Lazenby, A.; Birkenmeier, Edward H.; Sundberg, John P.; Elson, Charles O.

1998-01-01

C3H/HeJBir mice are a new substrain that spontaneously develop colitis early in life. This study was done to determine the T cell reactivity of C3H/HeJBir mice to candidate antigens that might be involved in their disease. C3H/HeJBir CD4+ T cells were strongly reactive to antigens of the enteric bacterial flora, but not to epithelial or food antigens. The stimulatory material in the enteric bacteria was trypsin sensitive and restricted by class II major histocompatibility complex molecules, but did not have the properties of a superantigen. The precursor frequency of interleuken (IL)-2–producing, bacterial-reactive CD4+ T cells in colitic mice was 1 out of 2,000 compared to 1 out of 20,000–25,000 in noncolitic control mice. These T cells produced predominately IL-2 and interferon γ, consistent with a T helper type 1 cell response and were present at 3–4 wk, the age of onset of the colitis. Adoptive transfer of bacterial-antigen–activated CD4+ T cells from colitic C3H/HeJBir but not from control C3H/HeJ mice into C3H/HeSnJ scid/scid recipients induced colitis. These data represent a direct demonstration that T cells reactive with conventional antigens of the enteric bacterial flora can mediate chronic inflammatory bowel disease. PMID:9500788

The hSK4 (KCNN4) isoform is the Ca2+-activated K+ channel (Gardos channel) in human red blood cells

PubMed Central

Hoffman, Joseph F.; Joiner, William; Nehrke, Keith; Potapova, Olga; Foye, Kristen; Wickrema, Amittha

2003-01-01

The question is, does the isoform hSK4, also designated KCNN4, represent the small conductance, Ca2+-activated K+ channel (Gardos channel) in human red blood cells? We have analyzed human reticulocyte RNA by RT-PCR, and, of the four isoforms of SK channels known, only SK4 was found. Northern blot analysis of purified and synchronously growing human erythroid progenitor cells, differentiating from erythroblasts to reticulocytes, again showed only the presence of SK4. Western blot analysis, with an anti-SK4 antibody, showed that human erythroid progenitor cells and, importantly, mature human red blood cell ghost membranes, both expressed the SK4 protein. The Gardos channel is known to turn on, given inside Ca2+, in the presence but not the absence of external \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} \\begin{equation*}{\\mathrm{K}}_{{\\mathrm{o}}}^{+}\\end{equation*}\\end{document} and remains refractory to \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} \\begin{equation*}{\\mathrm{K}}_{{\\mathrm{o}}}^{+}\\end{equation*}\\end{document} added after exposure to inside Ca2+. Heterologously expressed SK4, but not SK3, also shows this behavior. In inside–out patches of red cell membranes, the open probability (Po) of the Gardos channel is markedly reduced when the temperature is raised from 27 to 37°C. Net K+ efflux of intact red cells is also reduced by increasing temperature, as are the Po values of inside–out patches of Chinese hamster ovary cells expressing SK4 (but not SK3). Thus the envelope of evidence indicates that SK4 is the gene that codes for the Gardos channel in human red blood cells. This channel is important

Phospholipase C delta 4 (PLCδ4) is a nuclear protein involved in cell proliferation and senescence in mesenchymal stromal stem cells.

PubMed

Kunrath-Lima, Marianna; de Miranda, Marcelo Coutinho; Ferreira, Andrea da Fonseca; Faraco, Camila Cristina Fraga; de Melo, Mariane Izabella Abreu; Goes, Alfredo Miranda; Rodrigues, Michele Angela; Faria, Jerusa Araújo Quintão Arantes; Gomes, Dawidson Assis

2018-06-01

Ca 2+ is an important second messenger, and it is involved in many cellular processes such as cell death and proliferation. The rise in intracellular Ca 2+ levels can be due to the generation of inositol 1,4,5-trisphosphate (InsP 3 ), which is a product of phosphatidylinositol 4,5-bisphosphate (PIP 2 ) hydrolysis by phospholipases C (PLCs), that leads to Ca 2+ release from endoplasmic reticulum by InsP 3 receptors (InsP 3 R). Ca 2+ signaling patterns can vary in different regions of the cell and increases in nuclear Ca 2+ levels have specific biological effects that differ from those of Ca 2+ increase in the cytoplasm. There are PLCs in the cytoplasm and nucleus, but little is known about the functions of nuclear PLCs. This work aimed to characterize phenotypically the human PLCδ4 (hPLCδ4) in mesenchymal stem cells. This nuclear isoform of PLC is present in different cell types and has a possible role in proliferative processes. In this work, hPLCδ4 was found to be mainly nuclear in human adipose-derived mesenchymal stem cells (hASC). PLCδ4 knockdown demonstrated that it is essential for hASC proliferation, without inducing cell death. An increase of cells in G1, and a reduction of cells on interphase and G2/M in knockdown cells were seen. Furthermore, PLCδ4 knockdown increased the percentage of senescent cells, p16 INK4A+ and p21 Cip1 mRNAs expression, which could explain the impaired cell proliferation. The results show that hPLCδ4 is in involved in cellular proliferation and senescence in hASC. Copyright © 2018 Elsevier Inc. All rights reserved.

Pharmacological characterization of the new histamine H4 receptor agonist VUF 8430

PubMed Central

Lim, Herman D; Adami, Maristella; Guaita, Elena; Werfel, Thomas; Smits, Rogier A; de Esch, Iwan JP; Bakker, Remko A; Gutzmer, Ralf; Coruzzi, Gabriella; Leurs, Rob

2009-01-01

Background and purpose: We compare the pharmacological profiles of a new histamine H4 receptor agonist 2-(2-guanidinoethyl)isothiourea (VUF 8430) with that of a previously described H4 receptor agonist, 4-methylhistamine. Experimental approach: Radioligand binding and functional assays were performed using histamine H4 receptors expressed in mammalian cell lines. Compounds were also evaluated ex vivo in monocyte-derived dendritic cells endogenously expressing H4 receptors and in vivo in anaesthetized rats for gastric acid secretion activity. Key results: Both VUF 8430 and 4-methylhistamine were full agonists at human H4 receptors with lower affinity at rat and mouse H4 receptors. Both compounds induced chemotaxis of monocyte-derived dendritic cells. VUF 8430 also showed reasonable affinity and was a full agonist at the H3 receptor. Agmatine is a metabolite of arginine, structurally related to VUF 8430, and was a H4 receptor agonist with micromolar affinity. At histamine H3 receptors, agmatine was a full agonist, whereas 4-methylhistamine was an agonist only at high concentrations. Both VUF 8430 and agmatine were inactive at H1 and H2 receptors, whereas 4-methylhistamine is as active as histamine at H2 receptors. In vivo, VUF 8430 only caused a weak secretion of gastric acid mediated by H2 receptors, whereas 4-methylhistamine, dimaprit, histamine and amthamine, at equimolar doses, induced 2.5- to 6-fold higher output than VUF 8430. Conclusions and implications: Our results suggest complementary use of 4-methylhistamine and VUF 8430 as H4 receptor agonists. Along with H4 receptor antagonists, both agonists can serve as useful pharmacological tools in studies of histamine H4 receptors. PMID:19413569

Genome-Wide Studies Reveal that H3K4me3 Modification in Bivalent Genes Is Dynamically Regulated during the Pluripotent Cell Cycle and Stabilized upon Differentiation

PubMed Central

Grandy, Rodrigo A.; Whitfield, Troy W.; Wu, Hai; Fitzgerald, Mark P.; VanOudenhove, Jennifer J.; Zaidi, Sayyed K.; Montecino, Martin A.; Lian, Jane B.; van Wijnen, André J.; Stein, Janet L.

2015-01-01

Stem cell phenotypes are reflected by posttranslational histone modifications, and this chromatin-related memory must be mitotically inherited to maintain cell identity through proliferative expansion. In human embryonic stem cells (hESCs), bivalent genes with both activating (H3K4me3) and repressive (H3K27me3) histone modifications are essential to sustain pluripotency. Yet, the molecular mechanisms by which this epigenetic landscape is transferred to progeny cells remain to be established. By mapping genomic enrichment of H3K4me3/H3K27me3 in pure populations of hESCs in G2, mitotic, and G1 phases of the cell cycle, we found striking variations in the levels of H3K4me3 through the G2-M-G1 transition. Analysis of a representative set of bivalent genes revealed that chromatin modifiers involved in H3K4 methylation/demethylation are recruited to bivalent gene promoters in a cell cycle-dependent fashion. Interestingly, bivalent genes enriched with H3K4me3 exclusively during mitosis undergo the strongest upregulation after induction of differentiation. Furthermore, the histone modification signature of genes that remain bivalent in differentiated cells resolves into a cell cycle-independent pattern after lineage commitment. These results establish a new dimension of chromatin regulation important in the maintenance of pluripotency. PMID:26644406

Mitochondrial free fatty acid β-oxidation supports oxidative phosphorylation and proliferation in cancer cells.

PubMed

Rodríguez-Enríquez, Sara; Hernández-Esquivel, Luz; Marín-Hernández, Alvaro; El Hafidi, Mohammed; Gallardo-Pérez, Juan Carlos; Hernández-Reséndiz, Ileana; Rodríguez-Zavala, José S; Pacheco-Velázquez, Silvia C; Moreno-Sánchez, Rafael

2015-08-01

Oxidative phosphorylation (OxPhos) is functional and sustains tumor proliferation in several cancer cell types. To establish whether mitochondrial β-oxidation of free fatty acids (FFAs) contributes to cancer OxPhos functioning, its protein contents and enzyme activities, as well as respiratory rates and electrical membrane potential (ΔΨm) driven by FFA oxidation were assessed in rat AS-30D hepatoma and liver (RLM) mitochondria. Higher protein contents (1.4-3 times) of β-oxidation (CPT1, SCAD) as well as proteins and enzyme activities (1.7-13-times) of Krebs cycle (KC: ICD, 2OGDH, PDH, ME, GA), and respiratory chain (RC: COX) were determined in hepatoma mitochondria vs. RLM. Although increased cholesterol content (9-times vs. RLM) was determined in the hepatoma mitochondrial membranes, FFAs and other NAD-linked substrates were oxidized faster (1.6-6.6 times) by hepatoma mitochondria than RLM, maintaining similar ΔΨm values. The contents of β-oxidation, KC and RC enzymes were also assessed in cells. The mitochondrial enzyme levels in human cervix cancer HeLa and AS-30D cells were higher than those observed in rat hepatocytes whereas in human breast cancer biopsies, CPT1 and SCAD contents were lower than in human breast normal tissue. The presence of CPT1 and SCAD in AS-30D mitochondria and HeLa cells correlated with an active FFA utilization in HeLa cells. Furthermore, the β-oxidation inhibitor perhexiline blocked FFA utilization, OxPhos and proliferation in HeLa and other cancer cells. In conclusion, functional mitochondria supported by FFA β-oxidation are essential for the accelerated cancer cell proliferation and hence anti-β-oxidation therapeutics appears as an alternative promising approach to deter malignant tumor growth. Copyright © 2015 Elsevier Ltd. All rights reserved.

Growth-inhibiting effects of taxol on human liver cancer in vitro and in nude mice

PubMed Central

Yuan, Jin Hui; Zhang, Ru Ping; Zhang, Ru Gang; Guo, Li Xia; Wang, Xing Wang; Luo, Dan; Xie, Yong; Xie, Hong

2000-01-01

AIM: To investigate the effects of taxol on SMMC-7721 human hepatoma and its mechanisms. METHODS: In vitro cell growth was assessed by trypan blue exclusion method. Experimental hepatoma model was established by seeding SMMC-7721 cells subcutaneously into Balb/c (nu/nu) nude mice. In vivo tumor growth was determined by measurement of tumor diameter with Vernier calipers. The syntheses of DNA, RNA and protein were analyzed by incorporation of 3H-thymidine, 3H-uridine and 3H-leucine respectively. Using light and electron microscopes to observe the morphological changes of cells including mitosis and apoptosis. RESULTS: Taxol was effective against SMMC-7721 human hepatoma cell growth in the ranges of 2.5 nmol/L-10 nmol/L- with mitotic arrest and apoptosis in vitro. DNA, RNA and protein syntheses in cells were also obviously suppressed by in vitro treatment of taxol for 72 h. Taxol at 2.5 nmol/L reduced 3H-thymidine uptake to about 34% of the control value (P ＜ 0.05). Increasing the dose of taxol to 20 nmol/L resulted in a greater decrease in 3H-thymidine incorporation to 60% of the control value (P ＜ 0.01). At a concentration of 20 nmol/L, the 3H-uridine and 3H-leucine uptakes were reduced to 52% (P ＜ 0.05) and 63% (P ＜ 0.01), respectively. In vivo, taxol significantly inhibited SMMC-7721 tumor growth at 10 mg/kg, i.p. once daily for 10 d. A more than 90% decrease in tumor volume was observed by day 11 (P ＜ 0.01) similarly with mitotic arrest and cell apoptosis. CONCLUSION: Taxol has a marked anticancer activity in SMMC-7721 human hepatoma both in vitro and in nude mice. Its mechanisms might be associated with mitotic arrest, subsequently, apoptosis of the hepatoma cells. No obvious toxicity was observed with in vivo administration of taxol. PMID:11819558

Adult 4-H Volunteer Empowerment in 4-H Youth Development Settings

ERIC Educational Resources Information Center

Olsen, Pamela

2009-01-01

The primary purpose of this study was to determine which factors related to adult 4-H volunteer empowerment in 4-H youth development settings. This study examined the relationship of adult 4-H volunteers' perceived leadership styles of Oregon 4-H Youth Development Educators (YDE) to the adult 4-H volunteer sense of empowerment. In addition,…

8-Substituted Pyrido[3,4-d]pyrimidin-4(3H)-one Derivatives As Potent, Cell Permeable, KDM4 (JMJD2) and KDM5 (JARID1) Histone Lysine Demethylase Inhibitors

PubMed Central

2016-01-01

We report the discovery of N-substituted 4-(pyridin-2-yl)thiazole-2-amine derivatives and their subsequent optimization, guided by structure-based design, to give 8-(1H-pyrazol-3-yl)pyrido[3,4-d]pyrimidin-4(3H)-ones, a series of potent JmjC histone N-methyl lysine demethylase (KDM) inhibitors which bind to Fe(II) in the active site. Substitution from C4 of the pyrazole moiety allows access to the histone peptide substrate binding site; incorporation of a conformationally constrained 4-phenylpiperidine linker gives derivatives such as 54j and 54k which demonstrate equipotent activity versus the KDM4 (JMJD2) and KDM5 (JARID1) subfamily demethylases, selectivity over representative exemplars of the KDM2, KDM3, and KDM6 subfamilies, cellular permeability in the Caco-2 assay, and, for 54k, inhibition of H3K9Me3 and H3K4Me3 demethylation in a cell-based assay. PMID:26741168

Anion- or Cation-Exchange Membranes for NaBH4/H2O2 Fuel Cells?

PubMed

Sljukić, Biljana; Morais, Ana L; Santos, Diogo M F; Sequeira, César A C

2012-07-19

Direct borohydride fuel cells (DBFC), which operate on sodium borohydride (NaBH4) as the fuel, and hydrogen peroxide (H2O2) as the oxidant, are receiving increasing attention. This is due to their promising use as power sources for space and underwater applications, where air is not available and gas storage poses obvious problems. One key factor to improve the performance of DBFCs concerns the type of separator used. Both anion- and cation-exchange membranes may be considered as potential separators for DBFC. In the present paper, the effect of the membrane type on the performance of laboratory NaBH4/H2O2 fuel cells using Pt electrodes is studied at room temperature. Two commercial ion-exchange membranes from Membranes International Inc., an anion-exchange membrane (AMI-7001S) and a cation-exchange membrane (CMI-7000S), are tested as ionic separators for the DBFC. The membranes are compared directly by the observation and analysis of the corresponding DBFC's performance. Cell polarization, power density, stability, and durability tests are used in the membranes' evaluation. Energy densities and specific capacities are estimated. Most tests conducted, clearly indicate a superior performance of the cation-exchange membranes over the anion-exchange membrane. The two membranes are also compared with several other previously tested commercial membranes. For long term cell operation, these membranes seem to outperform the stability of the benchmark Nafion membranes but further studies are still required to improve their instantaneous power load.

Microwave-assisted solid-phase synthesis of highly fluorescent carbon nanoparticles and its application in intracellular pH sensing.

PubMed

Yang, Shenghong; Chen, Xiao; Liu, Shuqin; Wang, Fuxin; Ouyang, Gangfeng

2018-08-15

Fluorescent carbon nanoparticles (FCNPs) have been deeply researched and widely applied in recent years due to their good optics performance, chemical stability and biocompatibility. Herein, a green and rapid microwave-assisted solid-phase synthesis (solvent-free) approach was proposed for the fabrication of highly FCNPs in a very short period of time, 4 min. The as-prepared FCNPs can emit a blue emission with quantum yield of up to 63.2% in water solution and show yellow fluorescence in the solid state. The FCNPs also exhibit special solvent effect that the fluorescence emission can be adjusted by controlling the solvent ratio of ethanol and water. Most importantly, the FCNPs possess a narrow-range pH response. The probe responds linearly and rapidly to minor pH fluctuations within the range of 3.47-5.10 and the correlation coefficient is above 0.99. The proposed FCNPs also exhibit high photostability and reusability. As expected, the cell imaging and intracellular pH monitoring was achieved successfully in living SMMC 7721 hepatoma cells by this probe. The FCNPs is promising as a convenient and general fluorescent pH sensor for bioimaging applications. Copyright © 2018. Published by Elsevier B.V.

Possible reduction of hepatoma formation by Smmu 7721 cells in SCID mice and metastasis formation by B16F10 melanoma cells in C57BL/6 mice by Agaricus blazei murill extract.