Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023890 (cirrhosis)
 42,195 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Our knowledge about molecular alterations during hepatocarcinogenesis is still fragmentary, due to lack of comprehensive genetic and epigenetic analyses in the same set of hepatocellular carcinomas (HCCs). In this study, we conducted a large-scale analysis, including mutation screening in 50 genes and methylation assays in three genes in 54 pairs of HCCs and their neighboring non-cancerous tissues. All samples were collected from the residents in Southeast China. We found HBV infection and chronic hepatitis/cirrhosis in 83.3% and 98.1% of the cases, respectively. Mutations were identified in 18 out of 54 (33.3%) samples, with p53 alterations in 14 cases and beta-catenin mutations in four tumors. No mutations were identified in the neighboring tissues. Interestingly, 9 out of 14 (64.3%) tumors carrying p53 mutations displayed substitution of serine by arginine at codon 249, a characteristic change believed to be induced by aflatoxin-B1. Furthermore, p53 mutation was significantly associated with shorter recurrence-free survival (P=0.004). The results also revealed aberrant methylation in two or more genes in as high as 90% of tumors and 40% of adjacent tissues. The frequency of RASSF1A hypermethylation was much higher than that of p16INK4a and HAI2 in both HCC and neighboring tissues, indicating that deregulation of RASSF1A may precede the other two genes. These data suggest that aberrant methylation occurs before mutation and is an early event in the development of this set of HCC. Our findings highlight p53 as a prognostic factor of HCC and RASSF1A as a potential target in preventing malignant transformation of hepatocytes.
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PMID:Large-scale analysis of the genetic and epigenetic alterations in hepatocellular carcinoma from Southeast China. 1835 1

CpG island methylator phenotype (CIMP) involves the targeting of multiple genes by promoter hypermethylation. Telomerase plays an important role in the development of cellular immortality and oncogenesis. To gain insight into the role of epigenetic aberration of telomerase-related genes in hepatocarcinogenesis, we determined a hypermethylation profile in HCC. We examined the promoter methylation status of 9 genes associated with telomerase activity in 120 HCC, 120 cirrhosis tissues and 10 normal liver tissues by methylation-specific PCR. Assay of telomerase activity was by TRAP-ELISA. The frequency of promoter methylation of each gene was P21 63.3%, P15 42.5%, P16 62.5%, P53 14.2%, RB 32.5%, P27 48.3%, WTI 54.2%, E2F-1 70.8% and P300 65.8% of 120 HCC. Methylation status of P21, P15, P16, WTI and E2F-1 was significantly associated with HCC and nontumor tissues (p < 0.05). CIMP+ was detected in 61.7% (74/120) HCC and 15% (18/120) cirrhosis tissues, no CIMP+ was present in normal liver tissues (p < 0.001). A significant difference between CIMP status and metastasis was been found in HCC (p < 0.001). Results showed that 94.6% (70/74) HCC and 55.6% (10/18) cirrhosis patients with CIMP+ show expression of high telomerase activity than 45.5% (10/22) HCC and 6.25% (1/16) cirrhosis patients with CIMP- (p < 0.001). CIMP lead to high levels of expression of telomerase activity through the simultaneous inactivation of multiple genes associated with telomerase activity by concordant methylation.
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PMID:CpG island methylator phenotype association with upregulated telomerase activity in hepatocellular carcinoma. 1854 60

The oncogenic hepatitis B virus X protein (HBx) and cyclooxygenase (COX)-2 are highly co-expressed in chronic hepatitis, cirrhosis and well-differentiated hepatocellular carcinoma (HCC). Although HBx is shown to activate COX-2, the functional consequences of this interaction in hepatocarcinogenesis remain unknown. Using an engineered hepatoma cell system in which the expression of wild-type p53 can be chemically modulated, we show here that COX-2 mediates HBx actions in opposing p53. Enforced expression of HBx sequestrates p53 in the cytoplasm and significantly abolishes p53-induced apoptosis. The anti-apoptotic Mcl-1 protein is suppressed by p53 but reactivated by HBx. The abrogation of apoptosis is completely reversed by specific COX-2 inhibition, suggesting that HBx blocks p53-induced apoptosis via activation of COX-2/PGE(2) pathway. We further show that COX-2 inhibition blocks HBx reactivation of Mcl-1, linking this protein to the anti-apoptotic function of COX-2. These results demonstrate that COX-2 is an important survival factor mediating the oncogenic actions of HBx. Over-expression of HBx and COX-2 may provide a selective clonal advantage for preneoplastic or neoplastic hepatocytes and contribute to the initiation and progression of HCC.
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PMID:COX-2 mediates hepatitis B virus X protein abrogation of p53-induced apoptosis. 1860 5

Egypt has possibly the highest Hepatitis C Virus (HCV) prevalence worldwide. A high proportion of HCV infections become chronic and lead to liver cirrhosis and hepatocellular carcinoma (HCC). The cellular and molecular mechanisms behind HCV infection complication are not completely understood although apoptosis has been implicated in this process. Using flowcytometry, we examined whether T lymphocyte; isolated from patients with HCV and HCV-associated HCC (HCV-HCC); are predestined in vivo to undergo spontaneous apoptosis. Also, the role of p53; a key protein in apoptotic process; in the development of HCC was examined. Our data showed that T cells were severely depleted in HCV-HCC patients and its spontaneous apoptosis was higher in patient groups as compared to normal controls. In addition, p53 expression in liver tissue (determined by ELISA) was higher in the HCC patient groups as compared to normal controls and correlated well with the HCC grade. In conclusion, HCV infection induces peripheral T cell apoptosis, depletion and subsequently immune-suppression and this may lead to persistence of infection. Also, p53 is implicated in the poor prognosis of HCV-HCC and could be used as a predictive marker to assess the prognosis of HCC patients.
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PMID:T cells are depleted in HCV-Induced hepatocellular carcinoma patients: possible role of apoptosis and p53. 1868 67

Hepatocellular carcinoma (HCC) constitutes the 5th most frequent cancer worldwide, and due to a lack of treatment options, HCC represents the 3rd most lethal cancer worldwide. The incidence of HCC is continuously rising in Europe and Northern America, which can be explained by spreading of hepatitis C virus infections. Systemic chemotherapy is not an option for most patients with HCC. The most promising strategy for systemic treatment of HCC is targeted therapy. Successful targeted therapy has to inhibit pathways which are necessary for tumor growth, even in the late stages of carcinogenesis. The p16/Rb, p53, and IGF2R checkpoints as well as oncogenic alterations of telomerase, c-myc, Wnt/beta-catenin, PI3K/Akt, hedgehog, and c-met/HGF are most frequently involved in human hepatocarcinogenesis. However, currently, the most attractive target for molecular therapy of HCC appears to be the vascular endothelial growth factor (VEGF). Phase I/II studies showed high progression-free survival rates with antibodies or small molecules targeting the VEGF receptor pathway. Recently, a randomized placebo-controlled phase III study showed that the multikinase inhibitor sorafenib, which inhibits VEGF and Raf, significantly improves survival of patients with advanced HCC and Child A cirrhosis. As a consequence of this study, sorafenib is now the first available drug for effective systemic treatment of patients with advanced HCC.
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PMID:Molecular pathogenesis and targeted therapy of hepatocellular carcinoma. 1885 56

Cellular senescence is a process leading to terminal growth arrest with characteristic morphological features. This process is mediated by telomere-dependent, oncogene-induced and ROS-induced pathways, but persistent DNA damage is the most common cause. Senescence arrest is mediated by p16(INK4a)- and p21(Cip1)-dependent pathways both leading to retinoblastoma protein (pRb) activation. p53 plays a relay role between DNA damage sensing and p21(Cip1) activation. pRb arrests the cell cycle by recruiting proliferation genes to facultative heterochromatin for permanent silencing. Replicative senescence that occurs in hepatocytes in culture and in liver cirrhosis is associated with lack of telomerase activity and results in telomere shortening. Hepatocellular carcinoma (HCC) cells display inactivating mutations of p53 and epigenetic silencing of p16(INK4a). Moreover, they re-express telomerase reverse transcriptase required for telomere maintenance. Thus, senescence bypass and cellular immortality is likely to contribute significantly to HCC development. Oncogene-induced senescence in premalignant lesions and reversible immortality of cancer cells including HCC offer new potentials for tumor prevention and treatment.
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PMID:Senescence and immortality in hepatocellular carcinoma. 1907 Apr 23

Hepatitis B virus (HBV) infection is a worldwide health problem and may develop to liver fibrosis, cirrhosis, and even hepatocellular carcinoma. To investigate the global proteome responses of liver-derived cells to HBV infection and IFNalpha treatment, 2-DE and MS-based analysis were performed to compare the proteome changes between HBV stably transfected cell line HepG2.2.15 and its parental cell line HepG2, as well as HepG2.2.15 before and after IFNalpha treatment (5000 IU/mL for 72 h). Compared to HepG2, 12 of 18 down-regulated and 27 of 32 up-regulated proteins were identified in HepG2.2.15. After IFNalpha treatment, 6 of 7 down-regulated and 11 of 14 up-regulated proteins were identified. Differentially expressed proteins caused by HBV infection were involved with cytoskeletal matrix, heat shock stress, kinases/signal transduction, protease/proteasome components, etc. Prohibitin showed a dose-dependent up-regulation during IFNalpha treatment and might play a potent role in anti-HBV activities of IFNalpha by enhancing the crossbinding p53 expression to achieve the apoptosis of HBV infected liver cells. Down-regulation of interferon-stimulated gene 15 (ISG15) in HepG2.2.15 and recovery by IFNalpha suggested its relationship with IFNalpha's anti-HBV effect.
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PMID:Proteome responses to stable hepatitis B virus transfection and following interferon alpha treatment in human liver cell line HepG2. 1924 31

Chronic infection with hepatitis C virus (HCV) is regarded as a risk factor for hepatocellular carcinoma (HCC), mostly in patients with liver cirrhosis. Present study aimed at evaluation of cellular expression of p53 protein, genetic TP53 changes in liver samples and anti-p53 in serum of patients with chronic hepatitis C virus infection. The expression of p53 protein were analysed by immunocytochemistry in liver biopsies from adult patients with chronic, long-lasting hepatitis C. In order to detect TP53 mutations, PCR/SSCP and sequencing were performed. Antibodies against p53 in serum were determined using enzyme immunoassay (ELISA).In two out of 14 examined patients TP53 point mutations were detected in the liver samples. In the first patient, a substitution of C to T was demonstrated in position 1 of the codon 250, resulting in substitution of proline by serine. The other patient carried a substitution of C to G in position 13274 of the intron 6. The patient carrying mutation in the codon 250 demonstrated morphological traits of liver cirrhosis and had high number of p53-immunoreactive cell nuclei in tissue. None of the patients manifested elevated titres of serum anti-p53. In the liver, significant positive correlations were disclosed between expression of p53 on one hand and grading and staging on the other. A negative correlation was disclosed between cellular expression of p53 and duration time of infection. In conclusions, genetic changes in TP53 can be detected also in non-neoplastic lesions linked to chronic HCV infection.
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PMID:p53 immunocytochemistry and TP53 gene mutations in patients with chronic hepatitis C virus (HCV) infection. 1941 35

Chronic hepatitis C viral infection can lead to cirrhosis and hepatocellular carcinoma. It is generally believed that hepatitis C infection is not oncogeneic per se, but that the presence of cirrhosis determines the increased risk for hepatocellular carcinoma. However, a search of surgical pathology files from two large tertiary care centers for the years 2001-2008 identified a total of 18 hepatocellular carcinomas in non-cirrhotic livers with chronic hepatitis C infection. In six cases the background livers showed bridging fibrosis, while the remainder showed lower stages of fibrosis. Cases were negative for clinical and serological evidence of hepatitis B co-infection, and occult hepatitis B test was negative by PCR of formalin-fixed, paraffin embedded tissues. The tumors were also negative for TP53, exon 7, codon 249 mutations, a characteristic mutation strongly linked to aflatoxin exposure. The hepatocellular carcinomas had typical histology with no enrichment for unusual growth patterns or histological features. Among all resected hepatocellular carcinomas in non-cirrhotic livers over this time period, the prevalence of 16% with HCV infection was significantly greater than that expected by chance. In conclusion, these results demonstrate that hepatocellular carcinomas can arise in livers chronically infected with hepatitis C but without cirrhosis. These findings raise the possibility that in some cases hepatitis C infection and inflammation can be directly oncogeneic. It is also possible that established cirrhosis may have regressed in some cases. Regardless of the mechanism, these findings highlight an important and previously under-recognized risk for hepatocellular carcinoma in HCV-infected individuals who do not have cirrhosis.
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PMID:Hepatitis C-associated hepatocellular carcinomas in non-cirrhotic livers. 1993 43

Biliary intraepithelial neoplasia (BilIN), a preneoplastic condition that may precede invasive intrahepatic cholangiocarcinoma (ICC), has been compared to pancreatic intraepithelial neoplasia (PanIN), a precursor lesion of pancreatic carcinoma. Biliary tract carcinoma development and progression is associated with several gene alterations, but BilIN lesions have yet to be studied in detail by molecular techniques. We describe a case of extensive intrahepatic biliary dysplasia, with lesions ranging from BilIN-1 to BilIN-3 lesions, and multifocal microscopic ICC in hepatitis C virus (HCV)- and alcohol-related cirrhosis. The small ICC foci had remained undetected prior to transplantation. Fluorescence in situ hybridization (FISH) analysis was performed on three foci of BilIN-3 lesions and on three microinvasive ICC foci with a combination of three FISH probes directed against genes frequently altered in pancreatic and biliary tract carcinomas. FISH analysis revealed a CDKNA2 heterozygous deletion in one BilIN-3 focus, and in one non-contiguous ICC focus, although the deletion was just above the chosen threshold. No deletions were detected in the genomic regions encoding TP53 and SMAD4. This report documents for the first time the development of multifocal ICC in the setting of extensive biliary dysplasia in a patient with three risk factors, HCV infection, alcohol abuse, and cirrhosis, and suggests heterogeneous carcinogenesis in ICC and possible involvement of the CDKNA2 gene.
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PMID:Extensive biliary intraepithelial neoplasia (BilIN) and multifocal early intrahepatic cholangiocarcinoma in non-biliary cirrhosis. 2042 86


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