Carcinoma, Hepatocellular ; enzymology ; pathology ; Glutathione Peroxidase ; Humans ; Liver Neoplasms ; enzymology ; pathology ; Thioredoxin-Disulfide Reductase

Telomerase is highly activated in human immortal cell lines and tumor tissues, whereas it is not activated in primary cell strains and many tumor-adjacent tissues. It is suggested that telomerase activation is one of the critical steps in malignant transformation. In the present study, the telomerase activity was investigated in hepatocellular carcinoma tissues and non-tumor liver tissues from Korean patients with chronic hepatitis and cirrhosis. Eighty two liver tissues (24 chronic hepatitis specimens, 34 cirrhosis specimens, and 24 hepatocellular carcinomas) were obtained from 23 chronic viral hepatitis patients, 19 cirrhosis patients (including 7 liver transplants), and 24 patients with hepatocellular carcinoma, of which the surrounding non-tumor liver tissues were available in 16 patients (1 chronic hepatitis and 15 cirrhosis). As negative controls, 3 normal liver tissues were included. Protein from liver specimens was purified by a detergent lysis method as described elsewhere, and telomerase activity was measured in 2 diluents of each sample (1:1 and 1:100) by a telomeric repeat amplification protocol (TRAP). Telomerase was strongly activated in 79% (19/24) of the hepatocellular carcinomas, while weakly in 8% (2/24) of the chronic hepatitis tissues and in 24% (8/34) of the cirrhosis tissues. All of 3 normal control livers showed no telomerase activation. No relationship could be observed between the enhancement of telomerase activity and tumor nature. None of the chronic heaptitis or cirrhosis patients with mild telomerase activation in the liver have developed hepatocellular carcinoma for at least 2 years of follow-up period. These results suggest that the strong enhancement of telomerase activity may be a critical part of hepatocarcinogenesis, although the exact mechanism of such high activation in hepatocellular carcinoma is not clear. In addition, further study will be necessary to clarify the reason why no telomerase activity detectable by a conventional TRAP can be seen in some hepatocellular carcinoma.
Adult ; Aged ; Carcinoma, Hepatocellular/pathology ; Carcinoma, Hepatocellular/enzymology* ; Cell Transformation, Neoplastic* ; Comparative Study ; Enzyme Activation ; Female ; Hepatitis, Chronic/enzymology ; Human ; Liver Cirrhosis/enzymology ; Liver Neoplasms/pathology ; Liver Neoplasms/enzymology* ; Male ; Middle Age ; Precancerous Conditions/enzymology* ; Telomerase/analysis*

OBJECTIVETo study the role of arginase-1 (Arg-1) expression in differential diagnosis of hepatocellular carcinoma (HCC), Arg-1 staining pattern in clear cell neoplasm (HCC and non-HCC) and Arg-1 expression in non-hepatocellular tumors.

METHODSSeventy-eight cases of HCC (including 8 cases of clear cell type and 70 cases of non- clear cell type) and 246 cases of non-hepatocellular neoplasms (including 29 cases of metastatic tumors such as breast cancer, nasopharyngeal carcinoma and neuroendocrine carcinoma, 77 cases of tumors with clear cell changes such as malignant melanoma, clear cell renal cell carcinoma and alveolar soft part sarcoma, and 140 cases of other types of tumors such as ovarian endometrioid adenocarcinoma, pituitary tumor and thyroid papillary carcinoma) were studied.Immunohistochemical study for Arg-1 was performed on the paraffin-embedded tumor tissue.

RESULTSIn HCC, Arg-1 demonstrated both cytoplasmic and nuclear staining, with an overall sensitivity of 96.2% (75/78).In well, moderately and poorly differentiated HCC, the sensitivity was 15/15, 100% (41/41) and 86.4% (19/22), respectively. That was in contrast to negative staining for Arg-1 in all the 29 cases of metastatic tumors studied. The sensitivity, specificity, positive predictive value and negative predictive value of Arg-1 in distinguishing HCC from metastatic tumors was 96.2%, 100%, 100% and 90.6%, respectively. Cytoplasmic and membranous staining was observed in clear cell type of HCC. The overall sensitivity of Arg-1 expression in the 77 cases of tumors with clear cell changes was 14.3% (11/77), including 8/15 for malignant melanoma, 2/4 for ovarian clear cell carcinoma and 1/1 gall bladder adenocarcinoma with clear cell component.In malignant melanoma and ovarian clear cell carcinoma, only cytoplasmic staining was demonstrated. There was no expression of Arg-1 in the 140 cases of other tumor types studied.

CONCLUSIONSArg-1 is a sensitive and specific marker for HCC.It is a potentially useful immunohistochemical marker in distinguishing HCC from metastatic tumors. Though also expressed in malignant melanoma and ovarian clear cell carcinoma, Arg-1 shows a different staining pattern as compared with that in HCC.

Adenocarcinoma ; enzymology ; Adult ; Aged ; Arginase ; metabolism ; Carcinoma, Hepatocellular ; enzymology ; pathology ; secondary ; Cell Differentiation ; Diagnosis, Differential ; Female ; Gallbladder Neoplasms ; enzymology ; Humans ; Liver Neoplasms ; enzymology ; pathology ; secondary ; Male ; Melanoma ; enzymology ; Middle Aged ; Ovarian Neoplasms ; enzymology ; Stomach Neoplasms ; enzymology ; pathology

OBJECTIVETo investigate the changes of sugar chain structures of alkaline phosphatase (ALP) in hepatoma tissue and its relation to the invasiveness of hepatocellular carcinoma (HCC).

METHODSThe binding ratios of ALP from 9 normal liver tissues, 16 hepatoma tissues and 16 noncancerous tissues surrounding hepatoma were analysed by affinity chromatography on various lectin columns including leukoagglutinating phytohemagglutinin (L-PHA), lentil lectin (LCA), Datura stramonium agglutinin (DSA), erythroagglutinating phytohemagglutinin (E-PHA) and Sambucus nigra bark agglutinin (SNA).

RESULTSThe binding ratios of ALP on L-PHA (22.94%+/-5.30%), DSA (55.97%+/-13.72%), LCA (38.16%+/-8.87%), E-PHA (11.56%+/-4.81%) and SNA (69.80%+/-13.71%) in HCC tissues were significantly increased (P<0.01) compared with that in normal liver tissues (L-PHA 5.89%+/-2.75%, DSA 36.20%+/-11.58%, LCA 17.90%+/-6.71%, E-PHA 5.38%+/-2.20%, SNA 57.32%+/-11.27%), respectively. t values between the two groups were 8.94, 3.64, 5.94, 3.62 and 2.32, respectively. L-PHA-binding ratio (25.84%+/-4.67%) of ALP in HCC with invasiveness was significantly higher than that (18.10%+/-3.64%) without invasiveness (t=3.71, P<0.01).

CONCLUSIONThe changes of ALP sugar chain structures occur in HCC tissue. b1-6 branching sugar chain structure of ALP is related to the invasiveness of HCC.

Alkaline Phosphatase ; chemistry ; Carbohydrates ; chemistry ; Carcinoma, Hepatocellular ; enzymology ; pathology ; Chromatography, Affinity ; Humans ; Lectins ; metabolism ; Liver Neoplasms ; enzymology ; pathology ; Neoplasm Invasiveness

OBJECTIVETo prepare a monoclonal antibody against hepatoma-specific gamma-glutamyltransferase (GGT-II) and study it's application.

METHODSTwo Bal B/C mice were immunized with pure GGT-II, then their spleen cells were separated and fused to SP 2/0 myeloma cells so as to make hybridoma cell strain which could yield monoclonal antibody against GGT-II. And it's effect of binding GGT-II was detected by competitive inhibitory enzyme linked-immunosorbance assay (ELISA).

RESULTSA mouse hybridoma cell strain which could steadily secrete the monoclonal antibody against GGT-II was obtained and named 2G4F6B2. This monoclonal antibody belonged to IgG1 subclass and was specific to GGT-II, without cross-reaction to GGT-II. The result of detecting human serum GGT-II by ELISA with the monoclonal antibody accorded with that by polyacrylamide gradient electrophoresis.

CONCLUSIONThe monoclonal antibody against GGT-II prepared in this study has high specificity and can be applied in clinic to detect human serum GGT-II.

Animals ; Antibodies, Monoclonal ; Carcinoma, Hepatocellular ; diagnosis ; enzymology ; Enzyme-Linked Immunosorbent Assay ; Female ; Liver Neoplasms ; diagnosis ; enzymology ; Mice ; Mice, Inbred BALB C ; gamma-Glutamyltransferase ; analysis ; immunology

Adult ; Biomarkers, Tumor ; biosynthesis ; Carcinoma, Hepatocellular ; diagnosis ; enzymology ; DNA-Binding Proteins ; Female ; Humans ; Liver Neoplasms ; diagnosis ; enzymology ; Male ; Prognosis ; Telomerase ; biosynthesis ; genetics

Apoptosis ; drug effects ; Carcinoma, Hepatocellular ; enzymology ; pathology ; virology ; Hepacivirus ; genetics ; Humans ; Liver Neoplasms ; enzymology ; pathology ; virology ; Telomerase ; metabolism ; Viral Core Proteins ; genetics ; metabolism

Animals ; Carcinoma, Hepatocellular ; enzymology ; DNA-Binding Proteins ; Disease Models, Animal ; Liver Neoplasms ; enzymology ; Male ; RNA ; genetics ; RNA, Messenger ; analysis ; Rats ; Rats, Wistar ; Telomerase ; genetics ; metabolism

Adult ; Aged ; Carcinoma, Hepatocellular ; enzymology ; Female ; Glutathione S-Transferase pi ; metabolism ; Humans ; Liver Neoplasms ; enzymology ; Male ; Methylation ; Methyltransferases ; metabolism ; Middle Aged

Apoptosis ; physiology ; Carcinoma, Hepatocellular ; enzymology ; pathology ; Carrier Proteins ; biosynthesis ; genetics ; DNA-Binding Proteins ; metabolism ; Gene Targeting ; Humans ; Liver Neoplasms ; enzymology ; pathology ; RNA Interference ; Telomerase ; metabolism ; Tumor Cells, Cultured