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Query: UMLS:C0019204 (hepatocellular carcinoma)
 71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cultured rat hepatoma cells (HTC-cells) were used to study the uptake of copper and zinc from a minimal salt-glucose medium, supplemented with albumin from different species or with ovalbumin. Competitive equilibrium dialysis showed that at low molar ratios of metal/protein (less than 1) the affinity for copper of human and bovine albumin was about equal, but that of dog albumin or ovalbumin was much lower. Only a small difference in affinity for zinc could be detected between human albumin and ovalbumin. Supplementing the medium with the different proteins the rate of copper uptake in the cell at a given molar Cu/protein ratio increased as follows: human albumin congruent to bovine albumin less than dog albumin less than ovalbumin. When the molar Cu/protein ratio was increased, a discontinuity was seen with all three albumin species at a ratio of about 1. In contrast, the zinc uptake mimics that of Cu/ovalbumin, and no discontinuity was observed using different molar Zn/protein ratios. These results indicate that the rate of copper and zinc uptake depends strongly on its affinity for the protein: a low affinity leads to a high uptake. The results suggest further that at physiologic concentrations zinc is taken up by a mechanism different from that for copper.
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PMID:Trace element uptake in liver cells. 2. Effect of different proteins in the medium on the uptake of copper and zinc by hepatoma cells. 404 49

Serum-free, hormonally defined media have been developed for optimal growth of a rat hepatoma cell line. The cells' hormonal requirements for growth are dramatically altered both qualitatively and quantitatively by whether they were plated onto tissue culture plastic or collagenous substrata. On collagenous substrata, the cells required insulin, glucagon, growth hormone, prolactin, and linoleic acid (bound to BSA), and zinc, copper, and selenium. For growth on tissue culture plastic, the cells required the above factors at higher concentrations plus several additional factors: transferrin, hydrocortisone, and triiodothyronine. To ascertain the relative influence of hormones versus substratum on the growth and differentiation of rat hepatoma cells, various parameters of growth and of liver-specific and housekeeping functions were compared in cells grown in serum-free, hormonally supplemented, or serum-supplemented medium and on either tissue culture plastic or type I collagen gels. The substratum was found to be the primary determinant of attachment and survival of the cells. Even in serum-free media, the cells showed attachment and survival efficiencies of 40-50% at low seeding densities and even higher efficiencies at high seeding densities when the cells were plated onto collagenous substrata. However, optimal attachment and survival efficiencies of the cells on collagenous substrata still required either serum or hormonal supplements. On tissue culture plastic, there was no survival of the cells at any seeding density without either serum or hormonal supplements added to the medium. A defined medium designed for cells plated on tissue culture plastic, containing increased levels of hormones plus additional factors over those in the defined medium designed for cells on collagenous substrata, was found to permit attachment and survival of the cells plated into serum-free medium and onto tissue culture plastic. Growth of the cells was influenced by both substrata and hormones. When plated onto collagen gel substrata as compared with tissue culture plastic, the cells required fewer hormones and growth factors in the serum-free, hormone-supplemented media to achieve optimal growth rates. Growth rates of the cells at low and high seeding densities were equivalent in the hormonally and serum-supplemented media as long as comparisons were made on the same substratum and the hormonally supplemented medium used was the one designed for that substratum. For a given medium, either serum or hormonally supplemented, the saturation densities were highest for tissue culture plastic as compared with collagen gels.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Regulation of growth and differentiation of a rat hepatoma cell line by the synergistic interactions of hormones and collagenous substrata. 613 87

Analysis of tissue from a recent case of fibrolamellar liver cell carcinoma by several staining and spectrophotometric methods demonstrated elevated copper and copper-binding protein (CBP) in malignant hepatocytes. Production of CBP has not previously been described for this or any other type of hepatocellular carcinoma. Identification of CBP in liver cell carcinoma adds further evidence that this protein is a normal synthetic product of liver cells which may reappear in chronic cholestasis or hepatic malignancy. The mechanism of disturbed copper homeostasis in this case is uncertain.
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PMID:Copper and copper-binding protein in fibrolamellar liver cell carcinoma. 618 96

The tripeptide H-Gly-His-Lys-OH (GHL) is a human plasma constituent which has been previously shown to modulate the growth and viability of a variety of cell types and organisms. Experimental observations presented herein indicate that GHL is complexed with the transition metal ions Cu++ and Fe++ in vivo and may exert its biological effects as a peptide-metal chelate. At physiological pH in vitro, GHL associates with ionic copper, cobalt, iron, molybdenum, manganese, nickel, and zinc, but has no affinity for calcium, manganese, potassium, and sodium. GHL acts synergistically with copper, iron, cobalt, and zinc to alter patterns of cell growth in monolayer cultures of a tumorigenic hepatoma cell line (HTC4). These transition metals induce cellular flattening and adhesion to support surfaces, and inhibit DNA synthesis and lactic acid production when growth is limited by reduction of serum concentrations in medium. These inhibitory effects are neutralized, and intercellular adhesion and growth are stimulated by GHL in medium at nanomolar concentrations. Cu and Fe are the most active metals when combined with GHL. The results suggest that the inability of HTC4 cultures to replicate without adequate concentrations of serum in medium may reflect deficiency of GHL and transition metals, which appear to form complexes prior to interaction with cells. Chelation of transition metals with GHL and, potentially, with other growth-modulating peptide factors in plasma or medium, may provide a mechanism for expression and regulation of biological activities influenced by transition metals and polypeptide growth factors. The observed effects of GHL-metal complexes, including stimulation of cellular adhesiveness to substratum (flattening) and intercellular attachment (monolayer formation), appear to satisfy requirements for growth of hepatoma cells in monolayer culture.
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PMID:Growth-modulating tripeptide (glycylhistidyllysine): association with copper and iron in plasma, and stimulation of adhesiveness and growth of hepatoma cells in culture by tripeptide-metal ion complexes. 624 26

Many hepatic lesions, ranging from subcellular alterations to malignant tumors, have been attributed to the use of anabolic steroids (AS) and contraceptive steroids (CS). These lesions that have been attributed to AS and CS are discussed with focus on the following: biochemical changes; subcellular alterations; intrahepatic cholestasis; vascular complications (sinusoidal dilatation, peliosis hepatitis, Budd-Chiari syndrome); hyperplasia and neoplasia (diffuse hyperplasia, nodular transformation, focal nodular hyperplasia, hepatocellular adenoma, hepatocellular carcinoma, and miscellaneous malignant tumors); and miscellaneous effects (effects of preexisting liver disease, cholelithiasis, and pancreatitis). OCs have a number of physiologic effects on the liver. These include decreased bile flow, diminished secretion of organic anions, and decreased synthesis and secretion of bile acids. Retention of bromosulfophthalein has been noted with AS during late pregnancy and in the puerperium. It is well established that the CS can lead to elevations of serum ceruloplasmin and copper levels. Subcellular alterations have been reported in both humans and rats on AS or women on CS and involve multiple organelles of the several systems of the liver. Both AS and CS have been implicated in intrahepatic cholestasis. Jaundice usually develops after 2-5 months of therapy with AS or after 3 months of OC use. The lesions attributed to CS and AS can involve any of the systems of the liver. At times more than 1 system is affected simultaneously. Most of the steroid related lesions resemble similar ones caused by other etiologies. Some, such as peliosis hepatitis, are rarely related to other etiologies, but others can be termed steroid specific. A number of diseases associated with the CS or AS also occur in pregnancy. Acute fatty metamorphosis of pregnancy and the periportal hemorrhagic necrosis characteristic of eclampsia have not been reported in patients on CS. Spontaneous rupture of the liver during pregnancy has not been attributed to the CS.
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PMID:Hepatic lesions caused by anabolic and contraceptive steroids. 628 45

A pathogenetic relationship between hepatic manifestations of alpha 1-antitrypsin deficiency (AATD) and hepatocellular carcinoma has previously been suggested but not established. We encountered three patients with hepatocellular carcinoma (HCC) and nonneoplastic hepatocytes containing globules positive for alpha 1-antitrypsin by immunoperoxidase staining or immunofluorescence microscopy. The AATD was severe in one patient, mild in the second, and not evaluated in the third; any pathogenetic relationship between the deficiency and HCC must therefore remain speculative. Nonneoplastic hepatocytes of all three patients demonstrated copper storage and, in two patients who were not alcoholic, Mallory bodies. Simultaneous presence of copper storage and Mallory bodies has not been reported in liver disease associated with AATD. The pathogenetic mechanisms of these findings are unknown.
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PMID:alpha 1-Antitrypsin deficiency and hepatocellular carcinoma. Association with cirrhosis, copper storage, and Mallory bodies. 629 90

A male patient with Wilson's disease developed a hepatocellular carcinoma after treatment for nine years with D-penicillamine. Examination at necropsy showed that excess liver copper had been effectively removed. As copper has been shown to protect against chemically induced hepatocellular carcinoma in rats, this may be the reason for the extreme rarity of hepatocellular carcinoma in patients with Wilson's disease and possibly in other liver diseases with hepatic copper overload.
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PMID:Wilson's disease and hepatocellular carcinoma: possible protective role of copper. 630 37

Cultured rat hepatoma cells (HTC-cells) were used to study the transfer of copper from a well-defined medium to and across the cell membrane and particularly the role of albumin in this process. HTC-cells, maintained in a minimal salt-glucose medium, accumulated far more copper than when maintained in the same medium, but supplemented with albumin. In the latter case, the Cu uptake strongly depended on the molar Cu/albumin ratio. The results suggest a role of albumin in the uptake of trace metals. The results indicate the presence of two types of binding sites for copper on the cell membrane. The sites of the first type bind copper very strongly and are probably responsible for the uptake of copper under physiological conditions. Their number was estimated to be about 10(6) per cell. Those of the second type only bind copper when the molar Cu/albumin ratio exceeds a value of about 1, i.e., under extreme, unphysiological conditions. Furthermore, the results suggest a direct interaction of the Cu-albumin complex with these strong binding sites as a first step in Cu uptake processes.
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PMID:Trace metal uptake in liver cells. 1. Influence of albumin in the medium on the uptake of copper by hepatoma cells. 650 60

The plasma tripeptide glycyl-L-lysine (GHL), when added at nanomolar concentrations to a wide group of cultured systems, produces a disparate set of responses ranging from the stimulation of growth and differentiation to outright toxicity. Such diverse actions imply that this tripeptide mediates some basic biochemical function common to many types of cells and organisms. During the isolation of GHL we found the compound to co-isolate through a number of steps with approximately equimolar copper and about 1/5 molar iron. Maximal effects on hepatoma cells (HTC4) were seen when the peptide was added with copper and iron to the growth medium. Structure-function studies revealed that several tripeptides with a histidyl-lysyl linkage were nearly as active as GHL. The association of GHL with copper and a homology similarity between the tripeptide and the copper transport sites on albumin and alpha-fetoprotein, where the cupric atom is bound to a histidyl residue adjacent to a basic residue, suggested that GHL may act as a copper transport factor. We report here that the tripeptide readily forms complexes with copper(II) and enhances the uptake of the metal into cultured hepatoma cells.
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PMID:Growth-modulating plasma tripeptide may function by facilitating copper uptake into cells. 745 2

In the human metal storage disorders of Wilson's disease and primary haemochromatosis, ion transport and excretion dysfunctions result in the intracellular deposition of copper and iron, respectively. These aberrant accumulations of transition metal ions lead to extensive tissue damage, especially in the liver. In order to investigate the possible role of metal ion-mediated oxygen free radical-generated DNA damage in these processes, DNA was isolated from liver of eight Wilson's disease patients and six haemochromatosis patients. Significant levels of bulky DNA damage were detected in these samples by 32P-postlabelling analysis, but were not found in liver DNA from age-matched controls. This form of novel DNA damage was detected in six out of eight Wilson's patients, varying between approximately 1 and 100 base modifications per 10(8) nucleotides, and in all of the haemochromatosis samples examined; the levels of modified species per 10(8) nucleotides varying from approximately 2 to 50. HPLC analysis of these bulky DNA lesions demonstrated that the species formed in Wilson's disease and in haemochromatosis were chromatographically identical but were not the same as putative purine dimers that can be generated in DNA by in vitro incubation with Cu+/Fe2+ and H2O2 (although the possibility that the adducts detected are closely related has not been ruled out). Analysis of the oxidative base lesion 8-hydroxydeoxyguanosine showed that levels were not elevated in liver DNA from either Wilson's disease or haemochromatosis sufferers. In fact, a statistically significantly lower level of this lesion was found in Wilson's disease patients than in controls. These data suggest that bulky DNA damage present in the liver of both wilson's disease and primary haemochromatosis patients may play a more important role in the induction of tissue damage than 8-hydroxydeoxyguanosine. The novel DNA damage detected by 32P-poslabelling may also be a significant factor in the initiation of neoplasia leading to malignant hepatoma in haemochromatosis patients.
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PMID:Detection of bulky DNA lesions in the liver of patients with Wilson's disease and primary haemochromatosis. 752 89


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