Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

JunD is the most broadly expressed member of the Jun family and the AP-1 transcription factor complex. Primary fibroblasts lacking JunD displayed p53-dependent growth arrest, upregulated p19(Arf) expression, and premature senescence. In contrast, immortalized cell lines lacking JunD showed increased proliferation and higher cyclinD1 levels. These properties are reminiscent of the effects of oncogenic Ras expression on primary and established cell cultures. Furthermore, JunD(-/-) fibroblasts exhibited increased p53-dependent apoptosis upon ultraviolet irradiation and were sensitive to the cytotoxic effects of TNF-alpha. The antiapoptotic role of JunD was confirmed using an in vivo model of TNF-mediated hepatitis. We propose that JunD protects cells from senescence, or apoptotic responses to stress stimuli, by acting as a modulator of the signaling pathways that link Ras to p53.
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PMID:JunD protects cells from p53-dependent senescence and apoptosis. 1110 50

Hepatocellular carcinoma (HCC), a common cause of cancer deaths worldwide, has several major etiological risk factors, including infection with the hepatitis viruses and exposure to aflatoxin B1. A specific missense mutation resulting from a guanine to thymine transversion at the third position of codon 249 in the p53 tumor suppressor gene has been reported in 10-70% of HCCs from areas of high dietary exposure to aflatoxin B1. Short oligonucleotide mass analysis was compared with DNA sequencing in 25 HCC samples for specific p53 mutations. Mutations were detected in 10 samples by short oligonucleotide mass analysis in agreement with DNA sequencing. Analysis of another 20 plasma and tumor pairs showed 11 tumors containing the specific mutation, and this change was detected in six of the paired plasma samples. Four of the plasma samples had detectable levels of the mutation; however, the tumors were negative, suggesting possible multiple independent HCCs. Ten plasma samples from healthy individuals were all negative. This molecular diagnostic technique has implications for prevention trials and for the early diagnosis of HCC.
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PMID:Specific p53 mutations detected in plasma and tumors of hepatocellular carcinoma patients by electrospray ionization mass spectrometry. 1119 82

The coronavirus mouse hepatitis virus (MHV) directs the synthesis of viral RNA on discrete membranous complexes that are distributed throughout the cell cytoplasm. These putative replication complexes are composed of intimately associated but biochemically distinct membrane populations, each of which contains proteins processed from the replicase (gene 1) polyprotein. Specifically, one membrane population contains the gene 1 proteins p65 and p1a-22, while the other contains the gene 1 proteins p28 and helicase, as well as the structural nucleocapsid (N) protein and newly synthesized viral RNA. In this study, immunofluorescence confocal microscopy was used to define the relationship of the membrane populations comprising the putative replication complexes at different times of infection in MHV-A59-infected delayed brain tumor cells. At 5.5 h postinfection (p.i.) the membranes containing N and helicase colocalized with the membranes containing p1a-22/p65 at foci distinct from sites of M accumulation. By 8 to 12 h p.i., however, the membranes containing helicase and N had a predominantly perinuclear distribution and colocalized with M. In contrast, the p1a-22/p65-containing membranes retained a peripheral, punctate distribution at all times of infection and did not colocalize with M. By late times of infection, helicase, N, and M each also colocalized with ERGIC p53, a specific marker for the endoplasmic reticulum-Golgi-intermediate compartment. These data demonstrated that the putative replication complexes separated into component membranes that relocalized during the course of infection. These results suggest that the membrane populations within the MHV replication complex serve distinct functions both in RNA synthesis and in delivery of replication products to sites of virus assembly.
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PMID:Mouse hepatitis virus replicase protein complexes are translocated to sites of M protein accumulation in the ERGIC at late times of infection. 1141 2

Chronic hepatitis may progress to cirrhosis and hepatocellular carcinoma (HCC). Progressive accumulation of mutations and genomic instability in chronic viral hepatitis might flag an increased risk of HCC development. Genomic instability at dinucleotide microsatellite loci in chromosomes 2, 13, and 17 and at 2 mononucleotide repeat loci was examined in liver tissues from 41 patients, including 30 without HCC (18 patients with chronic hepatitis and 12 with cirrhosis) and 11 with HCC. Genomic instability was detected in 51% of the 41 cases. Allelic imbalance at informative dinucleotide loci occurred in 37% of the cases. In 14 cases (34%), allelic imbalance was detected in chronic hepatitis or cirrhosis without HCC. Allelic imbalance at the chromosome 13 locus was detected in 50% of the cases of chronic hepatitis C. Allelic imbalance at the TP53 chromosome locus and/or at the chromosome 13 locus was significantly more frequent than alterations at the chromosome 2 locus (P =.026). Low-level microsatellite instability was found in 20% of all cases examined and high-level microsatellite instability in 3 patients (7.5%), including 2 cases of chronic hepatitis and 1 case of cirrhosis. Our results show that allelic imbalance occurs frequently in hepatitis-related HCC as well as in chronic hepatitis in patients without HCC. Allelic imbalance at the D13S170 chromosome 13 locus (13q31.2) occurs frequently in chronic hepatitis, suggesting that genomic alterations affecting the long arm of chromosome 13 might be used to monitor the natural progression of chronic hepatitis-associated liver carcinogenesis.
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PMID:Genomic instability in chronic viral hepatitis and hepatocellular carcinoma. 1148 68

The presence of antibodies reacting with the p53 tumor suppressor protein has been described in patients with some autoimmune disorders. In this study we looked for serum anti-p53 antibodies in 64 patients with autoimmune type 1 diabetes mellitus within 4 mo of diagnosis. The presence of anti-p53 antibodies was observed in 6/64 (9.4%) subjects with type 1 diabetes, and in 1/44 (2.3%) subjects with other organ-specific autoimmune diseases (18 primary biliary cirrhosis, 10 autoimmune hepatitis, 16 thyroid diseases), but in none of 45 control subjects. No relationship was found between antibodies directed against islet- and non-islet-specific antigens and anti-p53 antibodies. These findings support a possible role for p53 in some autoimmune disorders.
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PMID:Serum anti-p53 autoantibodies in patients with type 1 diabetes. 1150 28

Since p21WAF1/CIP1 (p21) is a universal inhibitor of cyclin-dependent kinases and is regulated transcriptionally by p53, which is activated by DNA stress, its expression reflects DNA stress in chronic hepatitis. Recently an association with both hepatitis B and C virus and the expression of p53 or p21 was reported. We analyzed p21 expression in 18 cases of HBV-associated chronic liver diseases and 32 cases of HCV-associated chronic liver diseases by immunohistochemical analysis, and investigated the possible association between hepatocyte p21 expression and hepatic inflammation, fibrosis, and especially hepatitis virus type. The p21-positive hepatocytes were more numerous in areas of intense inflammation and spotty necrosis and areas close to fibrosis, and they increased according to the degrees of grading and staging. The p21 labeling index (LI) in patients with liver cirrhosis was significantly higher than that in patients with chronic hepatitis of both hepatitis viral types (5.84 +/- 0.61 vs 12.0 +/- 0.83, P < 0.0001 in hepatitis B, 10.28 +/- 0.80 vs 15.6 +/- 1.09, P = 0.0004 in hepatitis C), Furthermore, the p21 LI was significantly higher in HCV-associated liver disease than in HBV-associated liver disease in every group (4.02 +/- 0.48 vs 7.74 +/- 0.96, P = 0.021 in low grade group, 7.35 +/- 0.46 vs 12.8 +/- 0.57, P < 0.0001 in high grade, 12.0 +/- 0.83 vs 15.6 +/- 1.09, P = 0.034 in liver cirrhosis). In, conclusion, p21 expression was up-regulated by the stress of inflammation and fibrosis and might be influenced by viral proteins in human chronic liver disease.
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PMID:p21WAF1/CTP1 expression and hepatitis virus type. 1168 May 78

Tumor viruses can be found in both the RNA and DNA virus kingdoms. All RNA tumor viruses belong to the retrovirus family. Directly transforming Class I RNA tumor viruses carry cellular oncogenes, picked up by accidental recombination, and usually selected for secondary modifications and high tumorigenicity by the investigator. They are not known to play any role for tumor causation in nature. Class II or chronic RNA tumor viruses do not carry cell-derived oncogenes but they often act by proviral DNA insertion into the immediate neighborhood of a cellular oncogene. Feline, murine, and avian leukemia viruses belong to this category. The human adult T-cell leukemia virus, (HTLV-1) and bovine leukemia virus (BLV) act by expanding the preneoplastic cell population and thereby provides the soil for secondary, cellular changes. The DNA tumor viruses belong to three very different categories, the papovaviruses, adenoviruses and herpesviruses. Inactivation of the Rb and the p53 pathway by the viral transforming proteins is a convergent feature of the papova- and the adenoviruses. Since all DNA tumor viruses kill their host cell following their entry into the lytic phase, transformation and tumorigenicity are entirely dependent on a non-lytic interaction. Cells transformed by DNA tumor viruses depend on the continued expression of the virally encoded oncogene. They provide thereby a convenient target for the immune surveillance of the host. Depending on the epidemiological history of the virus in relation to its natural host species, the immune surveillance of the host and the strategy of viral latency and survival can evolve into a truly symbiotic relationship, as best illustrated by the Epstein-Barr virus (EBV). Tumor development occurs only as an accident at the level of the host (immunosuppression) or the cell (specific translocations or other genetic changes). The list of human viruses presently known to cause or to contribute to tumor development comprise four DNA viruses, namely Epstein-Barr virus, certain human papilloma viruses subtypes, hepatitis B virus, and Kaposi sarcoma herpesvirus (HHV-8); and two RNA viruses, adult T-cell leukemia virus (HTLV-1) and hepatitis virus C.
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PMID:Perspectives in studies of human tumor viruses. 1177

Hepatitis C Virus (HCV) is a single stranded RNA virus causing non-A and non-B hepatitis. Core protein is a viral capsid protein that plays an important role in the pathogenesis of HCV. The companion report revealed that an innate form (amino acids [a.a.] 1-191) regulated subcellular localization of a mature form (a.a. 1-173). It was also shown that the innate form in the cytoplasm enhanced the p21 expression and the mature form in the nucleus suppressed the p21 expression. Here we report that the core protein in the cytoplasm increases the amount of p21 via activating p53, and the core protein in the nucleus decreases the amount of p21 by the p53-independent pathway. These observations suggest that the regulation of p21 expression by the core protein via subcellular localization might decide the fate of infected cells either to the proliferation or to the apoptosis.
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PMID:Subcellular localization of HCV core protein regulates its ability for p53 activation and p21 suppression. 1205 98

The mutant strain Long-Evans Cinnamon (LEC) rat accumulates copper, resulting in spontaneous hepatitis and subsequent development of hepatocellular carcinomas (HCCs) in the liver, providing a promising model for investigation of the relationship between hepatitis induced by oxidative stress and hepatocarcinogenesis. We examined DNA strand breaks in peripheral blood cells and p53 expression in livers during acute and chronic hepatitis in LEC rats, along with preneoplastic lesions, and cell proliferation and apoptosis in non-cancerous portions of livers from LEC rats aged 7-115 weeks. Immunohistochemistry using antibodies against glutathione S-transferase placental-form (GST-P), proliferating cell nuclear antigen (PCNA), and in situ DNA nick labeling (TUNEL) were used. Long-Evans Agouti (LEA) rats, a sibling line of the LEC strain, were used as controls. In the LEC rats, DNA strand breaks and expression of p53 were significantly higher than that of LEA rats at 24 weeks of age. The number of GST-P-positive (GST-P+) foci/cm2 increased and peaked at 48 weeks old, and the areas rapidly expanded thereafter. The level of cell proliferation increased with the development of hepatitis and was highest at about 48 weeks old. The induction of apoptosis in LEC rats was transiently higher than that in LEA rats during the period from 24 to 34 weeks of age. However, the ratio of PCNA-positive cells to the apoptotic index showed a growth imbalance in favor of cell proliferation, supporting sustained net growth in LEC rats. These findings suggest that DNA damage, reflected in DNA strand breaks, plays a critical role in the development of hepatocellular preneoplastic foci, with an imbalance between high proliferation and relatively low apoptosis.
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PMID:DNA damage triggers imbalance of proliferation and apoptosis during development of preneoplastic foci in the liver of Long-Evans Cinnamon rats. 1223 13

Hepatocellular carcinoma (HCC) has several major etiological risk factors, including infection with hepatitis viruses and exposure to aflatoxin B(1). A specific missense mutation resulting from a guanine to thymine transversion at the third position of codon 249 in the p53 tumor suppressor gene has been reported in 10-70% of HCCs from areas of high dietary exposure to aflatoxin B(1.) This mutation has not only been detected in tumor samples but has also been measured in DNA isolated from the blood of patients with HCC in two separate studies by two independent methods: RFLP and short oligonucleotide mass analysis (SOMA), an electrospray ionization mass spectrometry technique. To compare the relative sensitivities of these methodologies, a set of serially diluted samples was analyzed by both techniques. The detection limits of RFLP and SOMA were 6% and 2.4% mutant alleles in the presence of wild-type alleles, respectively. When the DNA samples were predigested with HaeIII before SOMA, the detection limit was improved to 0.4% mutant allele in the presence of wild-type alleles. We have therefore found that SOMA is about 2.5-15-fold more sensitive than RFLP for detection of specific p53 mutations. A set of 26 DNA samples from HCC and normal liver was analyzed by RFLP and SOMA, and 5 samples were positive for the p53 mutation. An additional 4 samples were found to be positive for the mutation when SOMA was repeated after HaeIII predigestion.
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PMID:Sensitivity of electrospray ionization mass spectrometry detection of codon 249 mutations in the p53 gene compared with RFLP. 1237 21


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