Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019204 (hepatocellular carcinoma)
 71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Authors have successfully established 7 human hepatocellular carcinoma (HCC) cell lines. In one of these cell lines, JHH-7, derived from HBs antigen positive HCC, hepatitis B virus (HBV) genome was analyzed by Southern blot hybridization. Digesting with Hind III restriction endonuclease, two bands were obtained at 6.0 and 2.5 kb, that is the integration of HBV genome was confirmed at the two sites of chromosomes in this cell line. And analyzing with 32P labeled HBV-DNA fragments for probes, it was indicated that integrated HBV genome was incomplete one containing from X to C region.
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PMID:[Analysis for the integrated hepatitis B virus genome in cells of established human hepatocellular carcinoma cell line JHH-7]. 217 76

Analysis of AFP and albumin genes fails to demonstrate a correlation of gene activity with the degree of gene methylation as determined by restriction endonuclease fragments obtained using the isoschizomer pair, Hpa II and Msp I. There is no difference in the methylation patterns of DNA from high and low producing tissues, such as fetal and adult liver for AFP, hepatoma 7777 and 9098 for AFP; adult lung, brain, kidney and liver for albumin; fetal liver and brain or heart for AFP, etc. Minor selective differences in gene methylation that correlate with AFP or albumin gene expression cannot be ruled out.
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PMID:Lack of correlation of methylation and alphafetoprotein and albumin gene expression during liver growth, in hepatocellular carcinomas, and during hepatocarcinogenesis. 241 16

The DNA endonuclease (Aendo) and DNA topoisomerase (Atopo) activities in liver nucleus extracts of normal rats, in DENA-induced hepatomas and in liver tissues around tumours were investigated. The profile of nuclear endonucleases measured in the presence of 2 mM CaCl2 + 5 mM MgCl2, or 5 mM MnCl2, or 5 mM MgCl2, or 2 mM CaCl2 (pH 7.4), or I mM EDTA (pH 5.0) was different in normal and tumour tissues. Mn2+-dependent endonuclease was the main endonuclease in the tumour tissue, whereas Ca2+, Mg2+-dependent endonuclease was the main one in the normal liver and in the tissue around the tumour. An increase in the Mn2+-dependent endonuclease activity correlated with a decrease in the hepatoma differentiation level. Atopo of types I and II increased in the tissue around the tumour. Aendo and Atopo of cellular nuclei decreased in animals given DENA without the liver tumour.
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PMID:[The activity of nuclear endonucleases and topoisomerases in the liver of rats and in diethylnitrosamine-induced tumors]. 254 92

In order to investigate how chronic liver diseases, including liver cirrhosis and chronic hepatitis, are associate with hepatocarcinogenesis in terms of gene alteration, the methylation states of the c-myc and c-Ki-ras genes were examined in 34 liver tissues from patients with chronic liver disease without hepatocellular carcinoma (HCC), 34 non-tumor liver tissues from patients with HCC, 18 HCC tissues and 31 control liver tissues. The methylation states were analyzed by the Southern hybridization method using the restriction endonuclease isoschizomers MspI and HpaII. The CCGG sites at the second exon of the c-myc gene tended to be more extensively hypomethylated both in chronic liver disease and in non-tumor tissues than in control livers. Whereas the CCGG sites of the c-Ki-ras, and the third exon of the c-myc gene tended to be hypomethylated only in HCC tissues in comparison with other tissue groups. These results suggest that chronic liver disease may be situated between normal liver and HCC based on the state of DNA methylation and associated with the development of HCC through hypomethylation of the c-myc and/or c-Ki-ras gene.
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PMID:Hypomethylation of the c-myc oncogene in liver cirrhosis and chronic hepatitis. 254 2

Based on the following 3 points: 1) tumor proliferation is energy-dependent, 2) mitochondrial energy-production system is dominant for cell growth, and 3) liver mitochondria (mt) possess their own DNA and RNA synthesizing some of their own proteins including respiratory enzymes such as cytochrome oxidases, a possible relationship between mutations of mt-DNA and clinical status of cell proliferation was examined in 10 HCC patients who underwent liver resection. Mt-DNA at the cancerous and the noncancerous portions of 1g resected liver specimens were separated from the nuclear DNA, and then digested with Hinf I endonuclease. DNA filters were made of the digested mt-DNA fragments on the agarose and polyacrylamide gel. The filters were hybridized with a nick-translated 32P-labeled DNA fragments. In two cases, abnormal mt-DNA were detected. In the first case, the tumor was the massive type and grew rapidly invading the bile duct. One restriction fragment of 3.0 Kb of the cancerous and non cancerous portion became larger by 60 bp. In the second case, regarded as metachronous multicentric HCC, the second largest band of the 3.4 Kb fragment of the cancerous portion showed a wider range but not of the noncancerous portion. The former change may indicate polymorphism but the latter indicates an occurrence of the mutation of mt-DNA. Further studies are required, including examinations on the rest of mitochondrial fragments.
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PMID:[Analysis of human mitochondrial DNA in hepatocellular carcinomas]. 283 32

In order to determine whether integrated hepatitis B virus DNA sequences in primary liver tumours are methylated we have analysed tumour DNA digested with either MspI or HpaII restriction endonuclease by Southern hybridization. Our results demonstrate methylation in 11 of 17 tumour DNA samples. Where possible, we have examined the tumour tissues for expression of HBsAg and HBcAg using the indirect immunoperoxidase technique. One tumour was positive for both HBsAg and HBcAg and a second was positive for HBsAg alone. Both of these tumours were in the group in which methylation of integrated HBV DNA sequences could not be detected. We postulate that methylation of integrated HBV DNA sequences may influence HBV gene expression in hepatocellular carcinoma.
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PMID:Detection of hepatitis B virus DNA in hepatocellular carcinoma: methylation of integrated viral DNA. 283 61

DNA-dependent ATPase IV has been purified to near homogeneity from the Novikoff rat hepatoma. The enzyme is devoid of DNA polymerase, RNA polymerase, exonuclease, endonuclease, phosphomonoesterase, 3'- or 5'-phosphodiesterase, polynucleotide kinase, protein kinase, topoisomerase, helicase or DNA reannealing activities at a detection level of 10(-5) to 10(-7) relative to the ATPase activity. The enzyme is a monomer of Mr 110,000, has a sedimentation coefficient of 5.9 S, a Stokes radius of 40 A and a frictional coefficient of 1.32. In the presence of Mg2+ ion and a polynucleotide effector, ATPase IV hydrolyzes either ATP or dATP to the nucleoside diphosphate plus Pi. Other ribo- or deoxyribonucleoside triphosphates are not substrates. ATPase IV utilizes double-stranded DNA and single-stranded DNA as effector; however, it does not utilize poly(dT). The Km for dsDNA or ssDNA is 2.2 microM (nucleotide). A variety of ATP analogues were found to be competitive inhibitors of ATPase IV.
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PMID:Purification and enzymological characterization of DNA-dependent ATPase IV from the Novikoff hepatoma. 296 5

Hepatitis B virus surface antigen (HBsAg) mRNA has been enriched from a hepatoma cell line (PLC/PRF/5) by specific polysome immunoprecipitation and used for cDNA cloning. A HBsAg cDNA clone was identified by in situ hybridization with a cloned viral probe. It was characterized by restriction endonuclease mapping and DNA sequence analysis. Molecular hybridization of PLC/PRF/5 cellular DNA and RNA to [32P]-labeled HBsAg cDNA revealed the integration of at least six copies of the hepatitis B virus (HBV) DNA into the host genome and expression of three DNA species containing HBsAg-specific sequences. The possible role of HBV in the oncogenesis of primary hepatocellular carcinoma is discussed.
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PMID:Molecular cloning and characterization of the cDNA coding for hepatitis B virus surface antigen. 298 65

ApoB is a large glycoprotein with an apparent molecular mass of 550 kDa on NaDodSO4/PAGE. It is a major constituent of most lipoproteins and plays an important role in their metabolism. Recently, apoB cDNA clones have been isolated from an expression library made with mRNA from a human hepatoma cell line. These clones, which were all 1.5-1.6 kilobases (kb) long and corresponded to the 3' end of apoB mRNA, were used to demonstrate that hepatic apoB mRNA is approximately 22 kb long. In the current report, a probe derived from one of these cDNA clones, pB8, was used for in situ hybridization experiments to map the human gene for apoB, APOB, to the distal half of the short arm of chromosome 2. This probe was also used to analyze somatic cell hybrids and, in agreement with the in situ hybridization studies, concordancy was demonstrated with chromosome 2. In addition, two hybrids with chromosome 2 translocations that contain only the short arm reacted with the pB8 probe. A third hybrid with a complex rearrangement of chromosome 2, which deleted an interstitial region and the tip of the short arm of chromosome 2, did not react. These data indicate that APOB maps to either 2p21-p23 or 2p24-pter. In further studies, DNA from normal individuals, digested with the restriction endonuclease EcoRI and subjected to Southern blot analysis with the pB8 probe, revealed a two-allele restriction fragment length polymorphism (RFLP). The major allele was 11 kb, and the minor allele was 13 kb. The minor allele was present with a frequency of 20-25%. The inheritance of the two alleles was studied in an informative family, and they segregated in a typical autosomal Mendelian fashion. The mapping studies provide the means for understanding the relationship of the APOB locus to others in the human genome, whereas the demonstration of an APOB RFLP increases our ability to assess the role of this locus in determining plasma lipoprotein levels.
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PMID:Mapping of the human APOB gene to chromosome 2p and demonstration of a two-allele restriction fragment length polymorphism. 300 43

The methylation state of cellular oncogenes (c-oncs) and epidermal growth factor (EGF) receptor gene from human liver tissues was examined by means of restriction endonuclease analysis. c-myc and EGF receptor gene from hepatocellular carcinoma and fetal liver were substantially hypomethylated in comparison with those genes from normal liver, while the extents of methylation of c-mos and c-Ki-ras genes were the same among these tissues. It can be speculated that the specific hypomethylation of c-myc and EGF receptor genes may be associated with the development of hepatocellular carcinoma.
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PMID:Hypomethylation of c-myc and epidermal growth factor receptor genes in human hepatocellular carcinoma and fetal liver. 300 5


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