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)

ABCC6, a member of the adenosine 5'-triphosphate-binding cassette family of genes, encodes multidrug resistance-associated protein 6, a putative transmembrane transporter expressed primarily in the liver and to a significantly lower extent in other tissues. Mutations in ABCC6 result in pseudoxanthoma elasticum, a multi-system heritable connective tissue disorder with variable phenotypic expression. To examine the transcriptional regulation and tissue-specific expression of this gene, we cloned 2.6 kb of human ABCC6 promoter and developed a series of 5'-deletion constructs linked to luciferase reporter gene. Transient transfections in a number of cultured cell lines of diverse origin identified a specific NF-kappaB-like sequence (-235/-226), which conferred high level of expression in HepG2 hepatoma cells, inferring liver specificity. The functionality of the promoter fragments was confirmed in vivo by tail vein injection followed by luciferase reporter assay. Testing of selected cytokines revealed that transforming growth factor (TGF)-beta upregulated, while tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma downregulated the promoter activity in HepG2 cells. The responsiveness to TGF-beta was shown to reside primarily within an Sp1/Sp3 cognate-binding site at -58 to -49. The expression of the ABCC6 promoter was also shown to be markedly enhanced by Sp1 protein, as demonstrated by cotransfection of ABCC6 promoter-luciferase constructs and an Sp1 expression vector in Drosophila SL2 cells, which are devoid of endogenous Sp1. Furthermore, four additional transcription factors, with their cognate-binding sequences present in DNA, were shown to bind the 2.6-kb promoter fragment by protein/DNA array. Collectively, the results indicate that human ABCC6 displays tissue-specific gene expression, which can be modulated by proinflammatory cytokines. These findings may have implications for phenotypic expression of heritable and acquired diseases involving abnormality in the ABCC6 gene.
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PMID:Transcriptional regulation and characterization of the promoter region of the human ABCC6 gene. 1637 64

The severity of thalassemia intermedia depends on the degree of imbalance between alpha and non-alpha chains as well as other genetic and environmental factors that modify the natural history of the disease. By definition, the patients spontaneously maintain hemoglobin at or above 7 g/dL, sometimes at the price of intense hyperplasia of the bone marrow that is in turn responsible for bone deformities, osteoporosis, and extramedullary erythropoietic masses that often characterize thalassemia intermedia. Transfusion may become necessary with advancing age, during infection and pregnancy, and when hypersplenism develops. Splenectomy is often needed. Iron overload in nontransfused patients is due to increased gastrointestinal absorption and involves mainly the liver. Complications affecting the lives of patients with thalassemia intermedia include pulmonary hypertension, leg ulcers, pseudoxanthoma elasticum, gallstones, hepatocellular carcinoma, and thromboembolic events.
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PMID:The natural history of thalassemia intermedia. 2071 95

The life of patients with thalassemia has improved both in duration and in quality in industrialized countries. Complications are still common and include heart disease (heart failure and arrhythmias), chronic liver hepatitis, which can evolve in cirrhosis and, rarely, in hepatocellular carcinoma, endocrine problems (hypogonadism, hypothyroidism, diabetes, hypoparathyroidism), stunted growth, osteoporosis, thrombophilia and pseudoxanthoma elasticum. The incidence of complications is decreasing in younger cohorts of patients who have been transfused with blood that has been screened for viruses and thanks to the introduction of new oral iron chelators and imaging methods. The accurate measurement of iron deposits allows better management of iron overload. In addition, therapy for several complications is available. Specialized competence in treating patients with thalassemia is of great importance.
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PMID:Complications of thalassemia major and their treatment. 2166 99