Alkaloids ; pharmacology ; Animals ; Liver Neoplasms, Experimental ; enzymology ; prevention & control ; Quinolizines ; pharmacology ; Rats ; Selenium ; pharmacology ; Telomerase ; metabolism ; Yeast, Dried ; pharmacology

5'-nucelotidase and glucose-6-phosphatase are liver plasma and microsomal membranes markers and their respective activities were determined. In the liver homogenate, the activities of 5'-nucleotidase were 0.58 +/- 0.08 and 0.29 +/- 0.07 micromols/mg protein/10min in the control and 3'-methyl-4-dimethyl aminoazobenzene (3'-Me DAB) groups respectively. The enzyme activities m the partially purified plasma membranes were 2.15 +/- 0.25 and 1.31 +/- 0.23 micromols/mg protein/10min in the control and 3'-Me DAB groups respectively. The glucose-6-phosphatase activities in the homogenates of the control and 3'-Me DAB groups were 0.23 +/- 0.10, and 0.45 +/- 0.25 micromols/mg protein/10min, and in the microsomal fraction, 1.14 +/- 0.32, and 0.63 +/- 0.11 micromols/mg protein/10min, respectively, The concentrations of glucose carrier in the plasma membranes from the control and 3'-Me DAB group were 25, and 35 pmols/mg membrane protein, respectively, and the Ka values for cytochalsin B in each group were 5.20 X 109. and 5.14 X 109ml/mol, respectively. However in the microsomal fraction, no significant differences of glucose carrier were found between the control and 3'-Me DAB groups from the DEAE Sephadex A-50 ion exchange chromatography, fractions I and ll were obtained. Electrophoretic analysis of fraction I revealed a major protein band with a molecular weight of 45,000 and minor bands with MWs of 50,000, 55,000 and 15,000. Following AcA 34 gel filtration, a major protein band with a MW of 45,000 was obtained. From these results, it can be concluded that the glucose carrier protein was increased on plasma membrane of hepatoma induced by 3'-Me DAB, and the carrier protein showed similar molecular weight to other glucose carrier found in the RBC, muscle cells and adipocyte.
Animal ; Cell Membrane/enzymology ; Cell Membrane/metabolism ; Liver Neoplasms, Experimental/metabolism* ; Male ; Methyldimethylaminoazobenzene* ; Microsomes, Liver/enzymology ; Microsomes, Liver/metabolism ; Monosaccharide Transport Proteins/isolation & purification ; Monosaccharide Transport Proteins/metabolism* ; Rats ; Rats, Inbred Strains ; p-Dimethylaminoazobenzene*/analogs & derivatives

OBJECTIVETo compare the application of HE and enzyme histochemical staining in assessing the viability of hepatocellular carcinoma (HCC) cells coagulated by microwave ablation at different temperatures.

METHODSTwo groups of mice (n=6) with transplanted homogenic HCC were treated by microwave ablation at 60 degrees C and 50 degrees C for 3 min, respectively. Before and after microwave ablation, paraffin sections and frozen sections of the tumors were prepared for routine HE staining and enzyme histochemical staining with nicotinamide adenine dinucleotide diaphorase (NADH-diaphorase), respectively, and observed under microscope.

RESULTSShortly after microwave ablation, the morphology and arrangements of the nucleus of the ablated tumor cells in the two groups showed no obvious alteration in HE stained sections, but in sections with enzyme histochemical staining, the activity of NADH-diaphorase in ablated tumor tissue at 60 degrees C disappeared, suggesting the death of HCC cells; sporadic activity of the enzyme was detected in the coagulated tumor at 50 degrees C, indicating tumor cells surviving the ablation. The ablation effect was markedly different between the two groups (P<0.01).

CONCLUSIONHE staining is not suitable for evaluation of HCC destruction immediately after microwave ablation, and detection of NADH-diaphorase activity with the enzyme histochemical method better suits this purpose.

Animals ; Catheter Ablation ; methods ; Dihydrolipoamide Dehydrogenase ; metabolism ; Female ; Histocytochemistry ; methods ; Liver Neoplasms ; enzymology ; pathology ; therapy ; Liver Neoplasms, Experimental ; enzymology ; pathology ; therapy ; Mice ; Mice, Inbred C57BL ; Microwaves ; therapeutic use ; Temperature

Benzo(a)pyrene (BaP) is a polycyclic aromatic hydrocarbon (PAH) that is easily introduced to humans via consumption of grilled or smoked meat. BaP causes harmful oxidative effects on cell development, growth and survival through an increase in membrane lipid peroxidation, oxidative DNA damage and mutagenesis. Therefore, the present study was conducted to evaluate the synergistic effects of BaP on oxidative stress in hepatic tumors. In this study, we established a hepatic tumor model by injecting rat hepatoma N1-S1 cells into healthy rats. Changes in the abundance of heat shock proteins (HSPs), antioxidant enzymes and pro-inflammatory cytokines were then investigated by western blot analysis. In addition, we examined changes in oxidative stress levels. Injection of N1-S1 cells or concomitant injection of BaP and N1-S1 cells resulted in the formation of hepatic tumors at the injection site. Evaluation of rat plasma reveals that hepatic tumors induced by BaP and N1-S1 cells expresses higher levels of Hsp27, superoxide dismutase (SOD), and tumor necrosis factor-alpha (TNF-alpha) when compared to those induced by N1-S1 cells only. The collective results of this study suggest that BaP exerts synergistic effects on the expression of HSP, cytokines and antioxidant enzymes in hepatic tumors induced by rat hepatoma N1-S1 cells.
Animals ; Antioxidants/*metabolism ; Benzo(a)pyrene/*pharmacology ; Carcinoma, Hepatocellular/metabolism/pathology ; Cell Line, Tumor/*drug effects ; Cytokines/*metabolism ; Heat-Shock Proteins/*metabolism ; Humans ; Liver Neoplasms/*enzymology/*metabolism/pathology ; Male ; Neoplasms, Experimental/metabolism/pathology ; Oxidative Stress/drug effects ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo study location of MT1-MMP and effect of its change in expression on rabbit VX2 tumor tissues after transarterial embolization with hydroxyapatite nanoparticles loaded with lipiodol.

METHODSSixty rabbits implanted with tumor tissue of cell line VX2 were divided into three groups (control group, lipiodol group, hydroxyapatite nanoparticles loaded with lipiodol group). The transarterial embolization was performed super-selectively via gastro- duodenal artery of rabbits, each rabbit in control group was inserted with 1 ml normal saline,that in lipiodol group was inserted with 0.3 lipiodol ml/kg, also 0.3 ml hydroxyapatite nanoparticles loaded with lipiodol per kg for that in the last group. Results of embolization were detected by using CT scanning 3 days after operation. After two weeks, all tumors were took out as specimens to investigate location of MT1-MMP in VX2 tumor tissues,and also to determine the change of its expression in tumor tissues after embolization with different medicines, with three-step immunohistochemical technique (S-P). MT1-MMP mRNA was measured by RT-PCR to determine whether there were differences in three groups. Western blot technique was performed to determine difference of MT1-MMP protein expression of in three groups.

RESULTSImmunohistochemical results exposed that MT1-MMP was expressed on membrane of tumor cells and in extracellular matrix of tumor cells. Comparison of MT1-MMP expression in control group with that in other two groups, showed a significant lower level in control group (P < 0.05). There was no difference in MT1-MMP expression between lipiodol group, hydroxyapatite nanoparticles loaded with lipiodol group (P > 0.05). Western blot supported this conclusion. RT-PCR detecting MT1-MMP mRNA was found no differences among three groups (P > 0.05).

CONCLUSIONSMT1-MMP was mainly expressed on membrane of tumor cells and in extracellular matrix of tumor cells. There was an increasing tendency on expression of MT1-MMP in tumor tissues and extracellular matrix after transarterial embolization with hydroxyapatite nanoparticles loaded with lipiodol,it might be one of important mechanisms provoking high recurrence rate for hepatocellular carcinoma after treatment embolization.

Animals ; Durapatite ; Embolization, Therapeutic ; Iodized Oil ; Liver Neoplasms, Experimental ; enzymology ; pathology ; therapy ; Matrix Metalloproteinase 14 ; genetics ; metabolism ; Nanoparticles ; RNA, Messenger ; genetics ; Rabbits

Transferrin receptor (TR) performs the major function of binding and internalizing its specific iron-loaded ligand, transferrin, and its expression is closely linked to the proliferation status of the cell. This study was undertaken to elucidate TR expression in the hyperplastic lesion of hepatocyte in chemically induced hepatic carcinogenesis. The resistant hepatocyte model was chosen for a rat model of carcinogenesis and Sprague-Dawley rats were divided into the following groups: the control groups of normal diet and iron-rich diet with or without hydroxyquinoline and the groups of carcinogen alone and carcinogen plus iron-rich diet with or without administration of hydroxyquinoline. Microscopic changes in the liver, expression of transferrin receptor and glucose-6-phosphatase were studied. The hepatocyte of the control group showed both cytoplasmic and membranous expression of TR. The liver of rats fed on high iron diet accumulated iron and the expression of TR was down regulated by intrahepatic iron accumulation. In the carcinogen administered group the resistant hepatocyte of hyperplastic lesion revealed strong membranous expression of TR and failed to accumulate iron in spite of high iron diet but in contrast the surrounding non-resistant hepatocyte expressed TR in both the membrane and cytoplasm and stored iron when fed on high iron diet. The strong membranous expression of TR is one of the characteristics of the resistant hepatocyte of hyperplastic lesion and it seems to be related to the inability to accumulate iron in spite of a high iron diet.
Animal ; Glucose-6-Phosphatase/metabolism ; Immunohistochemistry ; Iron/analysis/pharmacology ; Liver/chemistry/enzymology/pathology ; Liver Neoplasms, Experimental/enzymology/*ultrastructure ; Male ; Rats ; Rats, Sprague-Dawley ; Receptors, Transferrin/*biosynthesis ; Support, Non-U.S. Gov't

OBJECTIVETo study the expression of enoyl CoA hydratase 1 (ECH1) and the effect when down-regulation of ECH1 gene expression in mouse hepatocarcinoma cell.

METHODSImmunofluorescence was used for detecting the expression of ECH1, and stably transfected Hca-F cells with pGPU6/GFP/Neo-shRNA-ECH1 expression plasmids. Cell proliferation was assessed by Cell counting kit-8 (CCK8) assay. The Boyden-transwell assay (8 µm pore size) was performed to analyze the inhibitory effect of shRNA on Hca-F cell migration and invasion.

RESULTSECH1 expression was obtained in the cytoplasm and upregulated expression in Hca-F cells than that in Hca-P cells. The down-regulation of ECH1 could inhibit the cell proliferation of Hca-F cells, decrease the number of cell pass through Transwell (27.07 ± 17.49) compared with scramble-negative (72.38 ± 18.83) and Hca-F controls (59.06 ± 30.33), decrease the migration capacities of Hca-F cells, increase the ratio of Hca-F cells in S phase (86.1%) compared with scramble-negative (75.8%) and Hca-F controls (66.2%) and decrease the ratio of G(1) phase (9.4%) compared with scramble-negative (24.2%) and Hca-F controls (30.3%).

CONCLUSIONECH1 serves as a potential critical factor attributes to tumor lymphatic metastasis.

Animals ; Cell Cycle ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Cytoplasm ; enzymology ; Down-Regulation ; Enoyl-CoA Hydratase ; genetics ; metabolism ; Gene Expression Regulation, Neoplastic ; Liver Neoplasms, Experimental ; enzymology ; pathology ; Lymphatic Metastasis ; Mice ; Plasmids ; RNA, Small Interfering ; genetics ; Transfection

OBJECTIVETo investigate the effect of enoyl coenzyme A hydratase-1 (Ech1) on the proliferation and invasion ability of mouse hepatocarcinoma Hca-P cells in vitro.

METHODSRecombinant pcDNA3.1(+)-Ech1 gene and pcDNA3.1(+) were transfected into Hca-P cells by cationic liposomes introduction. Clone of PEch1 cells that stably expressing Ech1 and clone of control Pvector cells were screened by G418. The Ech1 expression was identified subsequently by reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. The malignant behaviors of the cell lines were compared by proliferation, invasion and migration test.

RESULTSThe cell line Hca-P cells stably expressing Ech1 gene was constructed. The relative expression of Ech1 mRNA in the PEch1 group was 3.21 ± 0.43 and in the Pvector group was 1.44 ± 0.03, with a significant difference between the two groups (P = 0.029). The results of ELISA revealed that the expression of Ech1 protein was 0.140 ± 0.005 in the PEch1 group, 0.088 ± 0.003 in the Pvector group, and 0.078 ± 0.006 in the Hca-P group, showing a significant difference between the PEch1 group and the Pvector and Hca-P groups (P < 0.05). Transwell migration test showed that the number of penetrated cells in the PEch1 group was 143.00 ± 7.25 cells, significantly higher than that of the Pvector group (95.73 ± 3.88 cells) and un-treated Hca-1 group (106.67 ± 3.54 cells, both P < 0.05). The Transwell invasion assay showed that the number of penetrated cells was 77.20 ± 5.46 cells in the PEch1 group, significantly higher than 46.34 ± 4.35 cells in the Pvector group and 49.80 ± 5.21 cells in the un-treated Hca-1 group (both P < 0.05).

CONCLUSIONSThe results showed that overexpressed Ech1 in Hca-P cells may significantly increase the cell proliferation in a time-dependent manner. The up-regulation of Ech1 may increase to some extent the migration and invasion capacity of Hca-P cells. The efforts aiming at up-regulation of Ech1 expression may become a therapeutic target in the treatment of hepatocarcinoma.

Animals ; Carbon-Carbon Double Bond Isomerases ; genetics ; metabolism ; Cell Movement ; Cell Proliferation ; Liver Neoplasms, Experimental ; enzymology ; pathology ; Mice ; Neoplasm Invasiveness ; Plasmids ; RNA, Messenger ; metabolism ; Recombinant Proteins ; genetics ; metabolism ; Transfection ; Tumor Cells, Cultured ; Up-Regulation

This investigation was made with regard to the influences of ultrasound combined with hematoporphyrin on the activities of antioxidative enzyme in ascites hepatoma 22 (H-22) tumor cells, and to a better understanding of the potential biological mechanism of sonodynamic therapy which involved the damage to cells. Combined with 100 microg/ml hematoporphyrin, high intensity focused ultrasound sonication at a frequency of 1.43 MHz and an intensity level of 2.0 W/cm2 was delivered to H-22 tumor cells for 1 min. The viability of cells was evaluated by typan-blue blue exclusion test. The intracellular reactive oxygen species (ROS) levels were determined by 2',7'-dichlorofluorescein diacetata (DCFH-DA). Enzymatic chemical methods were used to measure the activities of key antioxidative enzymes. The results indicated that the cell damage rate of ultrasound combined with hematoporphyrin was significantly higher than that of the treatment with ultrasound alone, and hematoporphyrin alone had no killing effect on H-22 cells. The level of ROS in cell suspension was significantly increased, and the key antioxidative enzyme activities were obviously decreased after treatment with the combined use of ultrasound and hematoporphyrin. We speculated that the decreased activities of key antioxidative enzymes in cells might be involved in mediating the killing effect on H22 cells in sonodynamic therapy.
Animals ; Female ; Glutathione Peroxidase ; metabolism ; Hematoporphyrins ; administration & dosage ; radiation effects ; Liver Neoplasms, Experimental ; enzymology ; therapy ; Mice ; Mice, Inbred ICR ; Photochemotherapy ; methods ; Photosensitizing Agents ; administration & dosage ; radiation effects ; Superoxide Dismutase ; metabolism ; Ultrasonics

Hydroxyurea is commonly used to treat hematologic disorders and some type of solid tumors, but the mechanism for its therapeutic effect is not clearly known. In this study, we examined the effect of hydroxyurea on rat hepatoma McA-RH7777 cells, specifically, on the role of mitogen-activated protein (MAP) kinase signal transduction pathways and p21Waf1, p27Kip1 and p53. Rat hepatoma McA-RH7777 cells treated with hydroxyurea for 7 days, caused the inhibition of cell growth in a dose-dependent manner. But, this growth inhibition was not caused by necrosis or apoptosis but instead was associated with cell senescence-like change as evidenced by senescence associated-beta-galactosidase staining, and cells arrest at G1 phase of cell cycle. Phosphorylation of MAP kinases, such as ERK, JNK, and p38, was found to be decreased after treatment of cells with hydroxyurea. But, the expression of p21Waf1 was increased, while p27Kip1 and p53 were not detected in hydroxyurea treated rat hepatoma cells. Hydroxyurea treatment induced G1 arrest and a senescence-like changes in rat hepatoma McA-RH7777 cells may be the likely results of signal disruption of MAP kinases (ERK, JNK, and p38 MAP kinase) and p21Waf1 over-expression.
Animals ; Antineoplastic Agents/*pharmacology ; Cell Aging/drug effects ; Cell Cycle Proteins/analysis/metabolism/*physiology ; Cell Line, Tumor ; Cell Proliferation/drug effects ; G1 Phase/drug effects/physiology ; Hydroxyurea/*pharmacology ; Liver Neoplasms, Experimental/enzymology/*metabolism ; Mitogen-Activated Protein Kinases/analysis/*physiology ; Phosphorylation/drug effects ; Protein p53/analysis/metabolism ; Rats ; Research Support, Non-U.S. Gov't ; Tumor Suppressor Proteins/analysis/metabolism ; Up-Regulation