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)

The in vitro lymphokine-activated killer (LAK) activity of peripheral blood mononuclear cells (PBMC) from 36 patients with hepatocellular carcinoma was investigated. The activity was greatly diminished in 13 patients and enhanced in seven patients. A flow cytometric study showed that the percentage of OKM1+, Leu-7+-11b+, and Leu-7-11b+ fractions in PBMC was decreased and the percentage of OKT8+ and Leu7+11- fractions was increased significantly in the 13 patients with lower LAK activity, compared with the values of the seven higher LAK activity patients. Furthermore, the response of PBMC to interleukin-2 (IL-2) was deficient in the lower activity group. However, there was no significant difference in IL-2 production by PBMC, IL-2 receptor (p55) expression of PBMC and mitogen (Con-A, PHA) response of PBMC between the two groups. These findings indicate the possibility that diminished LAK activity in hepatoma patients is due to a decreased number of LAK precursor cells and a defective response of LAK precursor cells to IL-2.
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PMID:Defective immunological functions associated with abnormal lymphokine-activated killer activity in patients with hepatocellular carcinoma. 196 92

A cDNA coding for an allelic variant of rat IID1, designated IID1v, was isolated that produced a P-450 having a 10-fold lower catalytic activity toward the substrate bufuralol when expressed in COS-1 cells (Matsunaga, E., Zanger, U. M., Hardwick, J. P., Gelboin, H. V., Meyer, U. A., and Gonzalez, F. J. (1989) Biochemistry, 28, 7349-7355). IID1 and IID1v cDNA-deduced proteins differed in sequence by 4 amino acid residues. IID1 has Val, Phe, Arg, and Leu while IID1v has Ile, Leu, Gln, and Phe at amino acid positions 123, 124, 173, and 380, respectively. Chimeric cDNAs between IID1 and IID1v were constructed and expressed in hepatoma cells using vaccinia virus. A chimera having the Phe (IID1v) at amino acid 380, with the remaining 3 variant amino acid residues of IID1, was found to have a 17-fold decrease in Vmax and a 2 to 3-fold decrease in Km for (+)-bufuralol 1'-hydroxylation when compared to a converse chimera having Ile (IID1) in a background of IID1v sequence. Although this enzyme lacked significant bufuralol metabolism, it was able to carry out debrisoquine 4-hydroxylation. In contrast, the chimera having Ile (IID1) at position 380 was lacking in debrisoquine 4-hydroxylation. Type I difference spectra analysis revealed that both forms could bind debrisoquine with similar spectral dissociation constants. These data demonstrate that the single amino acid substitution Ile380----Phe differentially decreases the catalytic activity of IID1 toward bufuralol but not debrisoquine.
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PMID:Sequence requirements for cytochrome P-450IID1 catalytic activity. A single amino acid change (Ile380 Phe) specifically decreases Vmax of the enzyme for bufuralol but not debrisoquine hydroxylation. 197 28

Severe cachexia of extremely rapid onset typifies the young Black African patient with hepatocellular carcinoma (HCC). In order to assess whether this is a consequence of tumor-associated increases in protein metabolism or simply due to inadequate dietary intake, the following study was undertaken. The technique of constant i.v. infusion of 14C-labeled leucine was used to measure whole body protein flux, breakdown, synthesis, and oxidation rates in 8 adults with HCC, 4 patients with massive hepatomegaly due to metastatic adenocarcinoma from bowel, 6 patients with chronic liver disease, and 10 controls. Endogenous protein breakdown and oxidation were similar between patients with chronic liver disease (breakdown, 4.4 +/- 1.2 g/kg/day; oxidation, 0.8 +/- 0.4 g/kg/day) and controls but were significantly (P less than 0.002) higher in patients with liver tumors, the highest rates being observed in those with HCC (breakdown, 8.5 +/- 4.3 g/kg/day; oxidation, 1.4 +/- 0.5 g/kg/day). Protein turnover was generally higher in the HCC group, with increased rates of reincorporation of amino acids into protein synthesis (P less than 0.05). In one HCC patient a synchronized diagnostic liver biopsy demonstrated high fractional synthesis of rates of HCC proteins of 86%/day. In addition, the incorporation rates of labeled amino acid into fibrinogen, immunoglobulin G, and transferrin were also highest (P less than 0.03) in HCC patients. In order to assess the relative importance of diet in weight loss, dietary intake levels were assessed from hospital records of HCC patients and by dietary recall during the week prior to study. Intakes ranged from 30 to 70% of calculated requirement levels. In conclusion, our results suggest that the rapid wasting seen in patients with HCC is due to an imbalance between the metabolic demands, which can be elevated in some patients, and inadequate dietary replenishment.
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PMID:Contribution of elevated protein turnover and anorexia to cachexia in patients with hepatocellular carcinoma. 215 53

The expression of the c-myc gene has previously been shown to be elevated and deregulated in the human hepatoma cell line Hep G2 (B. E. Huber and S. S. Thorgeirsson, Cancer Res., 47: 3414-3420, 1987). We now report that the Hep G2 N-ras gene is activated to a dominant-acting, transforming gene by a missense mutation in codon 61. Hep G2 DNA produced transformed foci when transfected into NIH 3T3 cells. Subsequent to a secondary round of transfection, Southern blot analysis of tumorigenic NIH 3T3 foci demonstrated the presence of human N-ras sequences. Nucleotide sequence analysis of one Hep G2 N-ras allele demonstrated that codons 12, 13, and 59 were normal and that codon 61 had a missense mutation (CAA to CTA). This mutation results in the incorporation of leucine instead of glutamine at residue 61 of the N-ras gene product, p21. N-ras sequences were amplified by the polymerase chain reaction from both Hep G2 genomic DNA and Hep G2 complementary DNA. Analysis of the amplified sequences demonstrated that only one Hep G2 N-ras allele exhibited the codon 61 mutation and that both the mutant and normal alleles were transcribed. Northern blot analysis demonstrated equivalent steady-state levels of N-ras transcripts in Hep G2 cells and normal human liver. The steady-state levels of N-ras and ornithine decarboxylase transcripts were positively correlated suggesting a positive relationship between N-ras expression and the replication rate of Hep G2 cells. c-Ki-ras and c-Ha-ras transcripts were not detected in either Hep G2 cells or normal human liver. Immunoprecipitation experiments using the monoclonal antibody Y13-259 demonstrated the presence of p21 in Hep G2 cells. Expression of a dominant-acting, transforming N-ras gene, in conjunction with the altered regulation of the c-myc gene, documents two important genetic lesions that could be responsible for the transformed phenotype of Hep G2 cells.
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PMID:Characterization of a transforming N-ras gene in the human hepatoma cell line Hep G2: additional evidence for the importance of c-myc and ras cooperation in hepatocarcinogenesis. 215 25

Formation of the covalently stabilized complex of alpha 1-antitrypsin (alpha 1-AT) with neutrophil elastase, the archetype of serine proteinase inhibitor serpin-enzyme complexes, is associated with structural rearrangement of the alpha 1-AT molecule and hydrolysis of a reactive-site peptide bond. An approximately 4-kDa carboxyl-terminal cleavage fragment is generated. alpha 1-AT-elastase complexes are biologically active, possessing chemotactic activity and mediating increases in expression of the alpha 1-AT gene in human monocytes and macrophages. This suggested that structural rearrangement of the alpha 1-AT molecule, during formation of a complex with elastase, exposes a domain that is recognized by a specific cell surface receptor or receptors. To test this hypothesis, the known three-dimensional structure of alpha 1-AT and comparisons of the primary structures of the serpins were used to select a potentially exteriorly exposed and highly conserved region in the complexed form of alpha 1-AT as a candidate ligand (carboxyl-terminal fragment, amino acids 359-374). We show here that synthetic peptides based on the sequence of this region bind specifically and saturably to human hepatoma cells and human monocytes (Kd = 4.0 X 10(-8) M, 4.5 X 10(5) plasma membrane receptors per cell) and mediate increases in synthesis of alpha 1-AT. Binding of peptide 105Y (Ser-Ile-Pro-Pro-Glu-Val-Lys-Phe-Asn-Lys-Pro-Phe-Val-Tyr-Leu-Ile) is blocked by alpha 1-AT-elastase complexes, antithrombin III (AT III)-thrombin complexes, alpha 1-antichymotrypsin (alpha 1-ACT)-cathepsin G complexes, and, to a lesser extent, complement component C1 inhibitor-C1s complexes, but not by the corresponding native proteins. Binding of peptide 105Y is also blocked by peptides with sequence corresponding to carboxy-terminal fragments of the serpins AT III and alpha 1-ACT, but not by peptides having the sequence of the extreme amino terminus of alpha 1-AT. The results also show that peptide 105Y inhibits binding of 125I-labeled alpha 1-AT-elastase complexes. Thus, these studies demonstrate an abundant, relatively high-affinity cell surface receptor which recognizes serpin-enzyme complexes (SEC receptor). This receptor is capable of modulating the production of at least one of the serpins, alpha 1-AT. Since the ligand specificity is similar to that previously described for in vivo clearance of serpin-enzyme complexes, the SEC receptor may also be involved in the clearance of certain serpin-enzyme complexes.
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PMID:Identification of a serpin-enzyme complex receptor on human hepatoma cells and human monocytes. 216 76

Forty antiviral compounds were screened for inhibitory effect on hepatitis A virus (HAV) antigen expression in the human hepatoma cell line PLC/PRF/5. Ribavirin, amantadine, glycyrrhizin, and pyrazofurin were selected in this screening test and were studied further. The selectivity indices of these four compounds, calculated as the ratio of 50% cytotoxic dose (determined by the trypan blue exclusion and by inhibition of [3H] leucine incorporation) to the 50% effective dose (determined by the viral antigen expression), were 4.6 and 3.0 with ribavirin, 5.3 and 5.9 with amantadine, 15.2 and 16.9 with glycyrrhizin, and 45.4 and 74.6 with pyrazofurin. All four compounds resulted in concentration-dependent reductions of HAV antigen expression and HAV infectivity. Ribavirin, amantadine, pyrazofurin, and glycyrrhizin emerged, from the present study, as promising candidates for chemotherapy of acute hepatitis A.
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PMID:Inhibition of hepatitis A virus replication in vitro by antiviral compounds. 216 49

Unresectable hepatocellular carcinoma (HCC) has a poor prognosis and little sensitivity to anticancer agents. We planned a combination immunotherapy, associating with rIL-2 continuous injection. Combination immunotherapy consists of 5 different biological response modifiers (BRM), i.e., rIL-2, OK-432, adriamycin (ADR), cyclophosphamide (Cy), and famotidine (Fa). rIL-2, OK-432 and ADR were administered from implantable infuser port connecting to a catheter which was injected into the hepatic artery via the gastroduodenal artery under laparotomy. OK-432, Cy, and Fa were also administered systemically. From 1988 to 1990, seven patients with unresectable HCC and two patients who underwent curative resection were treated by this therapy. The objective responses were evaluated by CT and angiography. This combination immunotherapy produced 3 cases of complete response and 2 of minor response. Immunological monitoring of lymphocyte subsets and NK activity of peripheral blood mononuclear cells was also performed. NK activity was significantly augmented and the percentage of Leu 7(-) NCD 16(+) cells increased during this therapy. Serious toxicity, but transient high fever and hypotension, was not observed during this therapy. All of these patients left the hospital within two weeks and returned to their previous job or similar life activity. These results suggest that this combination immunotherapy is worth performing in further clinical trials for hepatocellular carcinoma.
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PMID:[Intraarterial combination immunotherapy in hepatocellular carcinoma]. 216 39

The in vitro lymphokine-activated killer activity and natural killer activity of peripheral blood mononuclear cells from 33 patients with hepatocellular carcinoma were investigated. Lymphokine-activated killer and natural killer activities of patients were significantly decreased compared with those of healthy volunteers. Peripheral blood mononuclear cells showed significantly lower lymphokine-activated killer and natural killer activities in patients with larger tumors (greater than or equal to 5 cm in diameter) than in patients with smaller tumors (less than 5 cm in diameter). Of 20 patients with larger tumors, 8 and 6 generated very little or no lymphokine-activated killer and natural killer activities. respectively. Lymphokine-activated killer precursors and natural killer cells were present mainly in the Leu-11+ fraction and partially in the Leu-7+ fraction in patients and normal volunteers. A flow cytometric study showed that the percentage of Leu-7+ 11+ and Leu-7-11+ fractions in peripheral blood mononuclear cells was lower in patients than in normal volunteers. The percentages of Leu-7-11+ and Leu-7+ 11+ fractions were diminished in the peripheral blood mononuclear cells of the patients with little or no lymphokine-activated killer activity. It is suggested that deficient lymphokine-activated killer and natural killer activities partially results from a reduction in the number of their precursor cells in patients with hepatocellular carcinoma.
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PMID:Depressed lymphokine-activated killer activity and analysis of the precursor cells in peripheral blood of patients with hepatocellular carcinoma. 217 25

Five hepatoma patients with small resectable tumour received an intratumoral injection of recombinant interleukin-2 (rIL-2) once weekly over 2-4 weeks (1.05 x 10(6)-3.6 x 10(6) U in total per patient). Tumour regressions of 32% and 57% were observed in two patients at day 42 after the first rIL-2 injection. No response was observed in two patients and disease progressed in one. Lymphokine-activated killer (LAK) activity was enhanced and Leu-11+ cells increased in the peripheral blood in the patients with 32% and 57% tumour regression after rIL-2 therapy. However, LAK activity, Leu-7+ cells were reduced in the patient who progressed. No consistent changes in Leu-2a+ cells and Leu-3a+ cells were demonstrated. In the three patients showing no response or 32% tumour regression, hepatic segments containing tumour were resected; histologically the tumour showed severe necrosis and lymphocytic infiltration in the patient with 32% tumour regression but mild or moderate changes in the other two. IL-2 mediated tumour killing can be induced in tumours by intratumoral injection of rIL-2, leading to tumour regression.
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PMID:Antitumour effect of intratumoral injection of human recombinant interleukin-2 in patients with hepatocellular carcinoma: a preliminary report. 217 45

In previous studies, we have found that combined treatment with BCNU and sodium cyanate could have a greater effect on the survival of mice bearing B16 melanoma than treatment with either agent alone. With rat hepatoma and human colon cancer cells in culture, we have obtained evidence that the inhibition of cell proliferation by sodium cyanate is greater at pH 6.6 than at pH 7.4. In the present work, the effects of combination treatments on the proliferation of cancer cells were studied with cyanate, pH, BCNU, and hyperthermia. With HT29 human colon cancer cells, the inhibitory effect of BCNU (50-100 micrograms/ml) was greater when the cells were treated at pH 6.6 than at pH 7.4. The influence of pH appeared to be absent or minimal at lower or higher concentrations of BCNU. We confirmed our previous observation that the inhibition of proliferation of LS174T human colon cancer cells is greater at pH 6.6 than at pH 7.4, and we observed an inhibitory effect of BCNU (50 or 200 micrograms/ml). However, no more than additive effects were seen with combination treatment. An inhibitory effect of hyperthermia was seen for the incorporation of [3H]-leucine into protein of rat hepatoma cells (HTC) and for that of [3H]-thymidine into DNA of human colon cancer (HT29) cells. In neither case was the effect of hyperthermia significantly enhanced by treatment with sodium cyanate beyond that seen with one of the treatments alone. The data confirmed that the inhibitory effect of sodium cyanate on cell proliferation can be enhanced by a low pH but did not provide evidence for synergistic effects in combination with BCNU or hyperthermia.
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PMID:Combined effect of pH and sodium cyanate on the inhibition of tumor cell proliferation and metabolism by BCNU and hyperthermia. 236 91


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