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 clinical pattern and the pathophysiological mechanism of the hereditary disorder alpha 1-antitrypsin deficiency are outlined. It appeared that the patient described suffered not only from emphysema, cirrhosis of the liver and hepatocellular carcinoma, but also from acute haemorrhagic pancreatitis. The combination of acute pancreatitis and alpha 1-antitrypsin deficiency has not been described before. Screening of relatives is important because of possible treatment.
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PMID:[Acute pancreatitis in a patient with alpha 1-antitrypsin deficiency. Is there a causal relationship?]. 841 21

Alpha 1-Antitrypsin deficiency predisposes to pulmonary emphysema, liver cirrhosis and hepatocellular carcinoma. Anecdotal evidence and a large autopsy study suggest that severe lung and liver disease rarely coexist in the same subject, but this has not been studied in patients. Therefore we investigated 27 patients with severe alpha 1-deficiency (Pi ZZ) and pulmonary emphysema for signs of liver disease and impaired hepatic function. A subgroup of 7 patients underwent quantitative liver function tests. On physical examination or ultrasonography, cirrhosis or tumor was not suspected in any patient. Conventional liver function tests were completely normal in 17 patients. Elevated serum activities of gamma-glutamyltranspeptidase and/or aminotransferases were seen in 10 patients. In some, the elevation was only marginal and in none more than twice normal. The serum bilirubin concentration and activity of alkaline phosphatase were increased in 1 patient. Serum protein, albumin, fibrinogen, antithrombin III, alpha 1-fetoprotein concentrations, serum activities of cholinesterase and glutamate dehydrogenase, activated partial thromboplastin time and prothrombin time were normal in all patients. The indocyanine green half-life was abnormal only in 1 of 6 patients, suggesting that hepatic blood flow was not impaired in the study group. However, the lidocaine half-life and galactose elimination capacity, parameters of hepatic metabolization, were impaired in 4 and 6 of 7 patients, respectively. We conclude that liver disease or impaired liver function is not a clinically relevant problem in most patients with pulmonary emphysema due to alpha 1-antitrypsin deficiency. But results of quantitative liver function tests, although performed in only a small group of patients, suggest that hepatic metabolization might be impaired even in those patients who present with pulmonary disease.
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PMID:Liver function in patients with pulmonary emphysema due to severe alpha-1-antitrypsin deficiency (Pi ZZ). 873 89

The serpin superfamily of serine proteinase inhibitors contains many members but the best-characterized is the plasma protein alpha 1-antitrypsin. its genetic deficiency is associated, in the homozygote, with hepatic damage that may progress to cirrhosis and hepatocellular carcinoma. Low levels of circulating alpha 1-antitrypsin fail to protect the lungs against proteolytic attack and predispose the homozygote to early onset pan-lobular emphysema, bronchiectasis and asthma. The major cause of alpha 1-antitrypsin deficiency, the Z mutation (Glu342Lys), results in the accumulation of protein in the endoplasmic reticulum of the liver. Using a structural approach, we have shown that the hepatic inclusions result from a protein-protein interaction between the reactive centre loop of one molecule and the beta-pleated sheet of a second. This loop-sheet polymerization is now also recognized to be the basis of deficiencies associated with mutations of C1-inhibitor, antithrombin and alpha 1-antichymotrypsin. Our recent solution of a crystal structure of a thermostable mutant of alpha 1-antitrypsin shows the detailed interactions that result in loop-sheet linkage and helps to explain the mechanism of action of this family of proteinase inhibitors.
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PMID:New insights into the structural basis of alpha 1-antitrypsin deficiency. 897 59

Patients with alpha1-antitrypsin (alpha1-AT) deficiency are at risk of developing early-onset panlobular basal emphysema, which has been attributed to uncontrolled proteolytic activity within the lung. Severe genetic deficiency of alpha1-AT is most commonly due to the Z mutation (342Glu--> Lys), which results in a block in alpha1-AT processing within the endoplasmic reticulum of hepatocytes. The retained alpha1-AT forms inclusions, which are associated with neonatal hepatitis, juvenile cirrhosis, and hepatocellular carcinoma. Our recent studies have shown that the accumulation of alpha1-AT is due to the Z mutation perturbing the structure of alpha1-AT to allow polymer formation, with a unique linkage between the reactive center loop of one alpha1-AT molecule and the A beta-pleated sheet of a second. The detection of loop-sheet polymers and other conformations of alpha1-AT in the lungs of patients with emphysema has been technically difficult. We show here that transverse urea-gradient-gel (TUG) electrophoresis and Western blot analysis may be used to characterize conformations of alpha1-AT in dilute samples of bronchoalveolar lavage fluid (BALF). This technique was used to demonstrate loop-sheet polymers in the lungs of patients with Z alpha1-AT-deficiency-related emphysema. Polymers were the predominant conformational form of alpha1-AT in BALF from the lungs of two of five Z homozygotes with emphysema, but were not detectable in any of 13 MM, MS, or MZ alpha1-AT controls. Because alpha1-AT loop-sheet polymers are inactive as proteinase inhibitors, this novel conformational transition will further reduce the levels of functional proteinase inhibitor in the lungs of the Z alpha1-AT homozygote, and so exacerbate tissue damage.
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PMID:Lung polymers in Z alpha1-antitrypsin deficiency-related emphysema. 956 37

Homozygous PIZZ alpha 1-antitrypsin deficiency, which has an incident of 1 in 1600 to 1 in 2000 live births, is the most common genetic cause of liver disease in children. It is also associated with chronic liver disease and hepatocellular carcinoma in adults. It is a well-known cause of pulmonary emphysema. Although emphysema is due to uninhibited proteolytic destruction of the connective tissue backbone of the lung, liver disease is thought to result from the toxic effects of the mutant alpha 1AT molecule retained within the endoplasmic reticulum of liver cells. Screening studies done by Sveger in Sweden have shown that only 10 to 15% of the PIZZ population develop clinically significant liver disease over the first 20 years of life. Recent studies have suggested that a subgroup of PIZZ individuals are predisposed to liver injury because of an inefficient degradation of mutant alpha 1ATZ within the endoplasmic reticulum. Altered migration of the abnormal alpha 1ATZ molecule in isoelectric focussing gels is the basis of the diagnosis of alpha 1AT deficiency. Treatment of alpha 1AT deficiency-associated liver disease is mostly supportive. Liver replacement therapy has been used successfully for severe liver injury. An increasing number of patients with severe emphysema have undergone lung transplantation.
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PMID:Alpha-1-antitrypsin deficiency. 977 22

It is now well known that the addition and trimming of oligosaccharide side chains during post-translational modification play an important role in determining the fate of secretory, membrane, and lysosomal glycoproteins. Recent studies have suggested that trimming of oligosaccharide side chains also plays a role in the degradation of misfolded glycoproteins as a part of the quality control mechanism of the endoplasmic reticulum (ER). In this study, we examined the effect of several inhibitors of carbohydrate processing on the fate of the misfolded secretory protein alpha1 antitrypsin Z. Retention of this misfolded glycoprotein in the ER of liver cells in the classical form of alpha1 antitrypsin (alpha1-AT) deficiency is associated with severe liver injury and hepatocellular carcinoma and lack of its secretion is associated with destructive lung disease/emphysema. The results show marked alterations in the fate of alpha1 antitrypsin Z (alpha1-ATZ). Indeed, one glucosidase inhibitor, castanospermine (CST), and two mannosidase inhibitors, kifunensine (KIF) and deoxymannojirimycin (DMJ), mediate marked increases in secretion of alpha1-ATZ by distinct mechanisms. The effects of these inhibitors on secretion have interesting implications for our understanding of the quality control apparatus of the ER. These inhibitors may also constitute models for development of additional drugs for chemoprophylaxis of liver injury and emphysema in patients with alpha1-AT deficiency.
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PMID:Glucosidase and mannosidase inhibitors mediate increased secretion of mutant alpha1 antitrypsin Z. 1063 1

Alpha-1-antitrypsin deficiency results from point mutations that distort the structure of the protein to allow a unique protein-protein interaction that we have termed loopsheet polymerisation. Polymers of Z alpha 1-antitrypsin accumulate within hepatocytes to form inclusion bodies that are associated with juvenile cirrhosis and hepatocellular carcinoma. The lack of circulating protein predisposes the Z alpha 1-antitrypsin homozygote to emphysema. This process also occurs in other members of the serine proteinase inhibitor (serpin) superfamily, antithrombin, C1-inhibitor and alpha 1-antichymotrypsin, in association with thrombosis, angioedema and chronic obstructive pulmonary disease, respectively, and we have recently shown that it underlies a novel inclusion body dementia. The interaction provides a useful paradigm for other 'conformational diseases' such as Huntington's disease, Creutzfeldt-Jakob disease and the amyloidoses.
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PMID:Alpha-1-antitrypsin deficiency, the serpinopathies and conformational disease. 1090 27

Alpha1-antitrypsin deficiency results from point mutations that distort the structure of the protein to allow a unique protein-protein interaction that we have termed loop-sheet polymerization. Polymers of Z alpha1-antitrypsin accumulate within hepatocytes to form inclusion bodies that are associated with juvenile cirrhosis and hepatocellular carcinoma. The lack of circulating protein predisposes the Z alpha1-antitrypsin homozygote to emphysema. This polymerization process also occurs in variants of other members of the serine proteinase inhibitor (serpin) superfamily, antithrombin, C1-inhibitor and alpha1-antichymotrypsin in association with thrombosis, angiooedema and chronic obstructive pulmonary disease respectively, and we have recently shown that it underlies a novel inclusion body dementia. Understanding this mechanism of polymerization allows rational drug design to block the protein-protein linkage and so ameliorate the associated disease.
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PMID:Loop-sheet polymerization: the mechanism of alpha1-antitrypsin deficiency. 1095 47

A 67-year-old male patient with pulmonary emphysema was diagnosed with liver cirrhosis. Further investigations revealed an alpha 1-antitrypsin deficiency caused by a PiZZ mutation. The liver cirrhosis was complicated by the development of a hepatocellular carcinoma. The patient died from the consequences of mesentary vein thrombosis. The protease inhibitor alpha 1-antitrypsin controls the tissue damaging effects of proteases which are produced by granulocytes. In the case of alpha 1-antitrypsin deficiency, progressive damage of the lung tissue occurs, resulting in emphysema. The accumulation of abnormal alpha 1-antitrypsin in hepatocytes can result in cirrhosis, with an increased chance of carcinoma. The deficiency is caused by a mutation in the Pi-gene on chromosome number 14. Although treatment options are at present limited, making an early diagnosis has important implications for the prognosis and intended management with respect to the prevention of complications, both in the patient as well as in first degree relatives (children and siblings).
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PMID:[Primary liver cell carcinoma as complication of alpha 1-antitrypsin deficiency in a 67 year old man]. 1110 73

Alpha 1-antitrypsin deficiency is the most common genetic cause of liver disease in children. It is also associated with chronic liver disease, hepatocellular carcinoma, and pulmonary emphysema in adults. Liver injury is caused by hepatotoxic effects of retention of the mutant alpha 1-antitrypsin molecule within the endoplasmic reticulum of liver cells, and emphysema is caused by uninhibited proteolytic damage to elastic tissue in the lung parenchyma. Recent studies of the biochemistry and cell biology of the mutant alpha 1-antitrypsin molecule have led to advances in understanding susceptibility to liver injury and in developing new strategies for prevention of both liver and lung disease.
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PMID:Liver injury in alpha 1-antitrypsin deficiency. 1123 97


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