Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P10415 (Bcl-2)
 33,771 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fas antigen (ag) is a cell surface protein known to trigger apoptosis in a variety of cells upon specific antibody binding. On the other hand, Bcl-2 protein, an oncogene product located at the mitochondrial inner surface, prolongs cell survival by blocking apoptosis. In this study we examined the expression of Fas ag and bcl-2 protein in 17 cases of hepatocellular carcinoma (HCC) to determine their role on HCC. By flow cytometric analysis, mean (SD) value of the expression of Fas ag on hepatocytes derived from normal liver, diseased liver (chronic hepatitis or liver cirrhosis) and HCC was 5.8 (4.7)%, 10.3 (6.9)%, and 24.0 (18.2)%, respectively. Fas ag expression on hepatoma cells was significantly greater than normal and diseased liver cells. The expression of Bcl-2 protein in normal liver, diseased liver and HCC was 4.3 (8.5)%, 0.8 (2.5)% and 2.1 (3.4)%, respectively, and the difference was not significant. These results suggest that induction of apoptosis may be a possible therapy against HCC.
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PMID:Expression of Fas antigen and Bcl-2 protein in hepatocellular carcinoma. 750 84

It has been thought that there is a particular balance between interferon and humoral immunity in the specific antiviral activity exerted by these systems. A possible relationship has been observed between some interferon-related proteins and the interferon serum level and a predictive significance can be assigned to MxA protein regarding the progression of some haematological malignancies. Both natural and recombinant interferon have been shown to be effective in the treatment of T-cell cutaneous lymphoma and the myeloma cell expression of Bcl-2 oncoprotein correlates to the response to interferon therapy in multiple myeloma patients. It has been thought that the combined therapy including interferon and cis-retinoic acid might be effective in the therapy of metastatic melanoma and breast cancer, whereas the combination of interferon with other chemotherapeutic agents appears to be effective in the treatment of hepatocellular cancer. It has been confirmed that interferon-alpha is useful in the therapy of chronic hepatitis C and a better knowledge regarding the mechanism of action of beta interferon in the therapy of multiple sclerosis has been acquired. Finally, a remarkable report regards the effectiveness of interferon in the therapy of idiopatic dilated cardiomiopathy.
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PMID:[Clinical use of interferon]. 911 15

Bcl-2 protein blocks apoptosis and is involved in human intrahepatic bile-duct development. Formalin-fixed, paraffin-embedded archival tissue from 42 HBV and HCV hepatitis [20 acute AH, 22 chronic hepatitis (CH)], 12 active cirrhosis (CR) and 20 hepatocellular carcinoma (HCC) was immunostained for bcl-2 protein. In all cases, bcl-2 protein was detected in portal and intralobular lymphocytes but not in hepatocytes or Kupffer cells. Bcl-2 was positive in the cytoplasm of small portal bile ducts of chronic hepatitis, while it was strongly expressed in newly formed bile-ductules of the limiting plate, mainly in CH with marked activity and CR. Bcl-2 was detected in small bile ducts in only one case of acute hepatitis and was not detected in any case of HCC. Bcl-2 seems to be involved in the regulation of growth and apoptosis of cholangiolar cells. Its expression in small bile ducts and in newly-formed ductules especially in CH with marked activity and CR, implies that the embryonic model of intrahepatic bile duct development may be recapitulated in chronic hepatic disease. Moreover, it supports evidence for the existence of the controversial long-lived stem population in the liver. Bcl-2 does not seem to be involved in hepatocarcinogenesis.
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PMID:Bcl-2 protein expression in acute and chronic hepatitis, cirrhosis and hepatocellular carcinoma. 1004 90

In primary biliary cirrhosis, biliary epithelial cell death by apoptosis results in progressive bile duct loss. We examined immunohistochemically 4 apoptosis-regulating bcl-2 familial proteins (bcl-2, mcl-1, bcl-X, and bax) in the biliary epithelium in 19 cases of primary biliary cirrhosis. Ten cases of chronic hepatitis C, 9 cases of extrahepatic biliary obstruction, and 10 cases of normal liver were used as a control. Bcl-2 and mcl-1 are inhibitors of apoptosis, bcl-X, probably bcl-XL in biliary epithelial cells, an inhibitor, and bax, a promoter of apoptosis. First, we clarified the distribution of bcl-2 familial proteins on the intrahepatic biliary tree in normal livers. Bcl-2 was detected in the interlobular bile ducts and bile ductules, but not in the large and septal bile ducts in all cases examined. Mcl-1, bcl-X, and bax were diffusely detectable at the any level of the intrahepatic biliary tree, with a staining pattern that was diffuse and cytoplasmic. This distribution pattern was preserved in extrahepatic biliary obstruction. Bcl-2 expression was lost or markedly reduced in the damaged interlobular bile ducts in primary biliary cirrhosis, whereas the reduction was only focal or mild in the bile ducts with hepatitis-associated damage in chronic hepatitis C. Expression levels of mcl-1, bcl-X, and bax were similarly reduced to that of bcl-2 in these 2 diseases. These findings suggest that bax is not important as a proapoptotic factor in the damaged bile ducts and that downregulation of bcl-2 and mcl-1, and probably that of bcl-XL, leads to a decrease in the threshold of apoptosis and increase in the vulnerability to apoptotic stimuli in these bile ducts, followed by the progressive apoptotic loss of interlobular bile ducts, in primary biliary cirrhosis.
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PMID:Expression of Bcl-2 familial proteins is reduced in small bile duct lesions of primary biliary cirrhosis. 1068 31

Bid, a member of the Bcl-2 family, mediates apoptosis by inducing the release of proapoptotic factors. The expression of Bid in liver diseases has not been investigated. This study evaluated Bid level in various liver diseases including hepatocellular carcinoma (HCC), liver metastases from colorectal cancer, chronic hepatitis and liver cirrhosis. The expression of Bid in tumorous tissues of HCC was lower than that in their corresponding non-tumorous tissues from the same patient. Heavy staining with Bid antibody was found in some localized tumorous liver tissues from patients with poorly differentiated tumors. In patients with chronic hepatitis and liver cirrhosis, there were gradient tumor-development centers, a gradient increase in reaction with Bid antibody from the middle of the center to its edge. The gradient tumor-development center was also found in non-tumorous tissues of HCC, suggesting that occurrence of this center in chronic hepatitis might be an early pathologic sign of HCC development. Bid was also expressed in the epithelial cells in tissues from liver metastases and their expression was often stronger than in the non-tumorous liver tissues. Heavy nuclear staining of Bid was not uncommon in these metastatic cells. The different patterns of staining between primary and secondary liver tumors may reflect a difference in tumor origin and in cell type. Nuclei of metastatic cells, though positive for Bid, still showed a considerable mitotic activity, indicating that they were in active proliferation rather than on a pathway deemed to be apoptotic. In conclusion, this study shows that the Bid level is decreased in HCC except in poorly differentiated HCC in which cells may undergo a process of apoptosis or necrosis. The existence of gradient tumor-development center in chronic hepatitis, liver cirrhosis and non-tumorous tissues from HCC may serve as a pathologic marker of a carcinogenic change of cell phenotypes.
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PMID:Immunohistochemical analysis of pro-apoptotic Bid level in chronic hepatitis, hepatocellular carcinoma and liver metastases. 1159 32

The role of the hepatitis B virus protein HBx in liver cell proliferation and apoptosis remains controversial. Using a transgenic mouse model, we have recently shown that HBx stimulates the apoptotic turnover of hepatocytes, independently of p53. In this paper, we tested whether the proapoptotic function of HBx can interfere with Bcl-2 during hepatic apoptosis in vivo. HBx transgenic mice were crossed with PK-hBcl-2 mice that are protected against Fas killing by constitutive overexpression of Bcl-2 in hepatocytes. In a lethal challenge with Fas antibodies, HBx expressed at low levels restored sensitivity to Fas-mediated apoptosis and fulminant hepatic failure in mice overexpressing Bcl-2. Furthermore, cytochrome c release from mitochondria and caspase 3 activation were restored to normal levels in HBx/Bcl-2 mice during transduction of the Fas signal. Thus, the proapoptotic activity of HBx overcomes or bypasses the inhibitory effect of Bcl-2 against Fas cytotoxicity. This effect was not apparently mediated through downregulation of the PK-hBcl-2 transgene or via delocalization of the Bcl-2 protein, and a direct interaction of HBx with Bcl-2, Bcl-X(L) or Bax could not be evidenced in yeast two-hybrid assays. We further show that apoptosis induced by ectopic expression of HBx is associated with mitochondrial membrane alterations and caspase 3 activation. Our data indicate that the dominant function of HBx upon Bcl-2-regulated control of apoptosis might play an important role in the pathogenesis of chronic hepatitis B.
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PMID:The hepatitis B virus X protein abrogates Bcl-2-mediated protection against Fas apoptosis in the liver. 1182 50

The Bcl-2 family proteins are important regulators of apoptosis and have been implicated in the occurrence of autoimmune diseases. There have been reports that Bcl-2-positive lymphocytes play important roles in pathogenesis of at least some types of autoimmune diseases, including autoimmune hepatitis. In this study, we examined the role of Bcl-2-positive lymphocytes in the development of primary biliary cirrhosis (PBC). The expression of Bcl-2 in lymphocytes infiltrating into the liver was evaluated from liver biopsy specimens of 25 patients with PBC (stage I/II/III/IV, 11/3/8/3) and 24 controls with chronic hepatitis B (CH-B) or chronic hepatitis C (CH-C). Bcl-2 expression in lymphocytes infiltrating into the liver was investigated by immunohistochemistry using a monoclonal antibody to Bcl-2 with an avidin-biotin complex system. Significant overexpression of Bcl-2 in lymphocytes infiltrating into the liver was observed in the early stage of PBC, especially in areas of destructed bile ducts. Most of Bcl-2-positive cells were CD45RO-positive helper T-cells visualized by the double staining method. These results suggest that Bcl-2-positive helper T-cells may have important roles in the pathogenesis of PBC.
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PMID:Enhanced expression of Bcl-2 in lymphocytes infiltrating into the liver of patients with primary biliary cirrhosis. 1201 72

Some viral infections are reported to influence the susceptibility of peripheral blood mononuclear cells (PBMC) to apoptosis, which is related to disease progression. The current study was designed to monitor apoptosis in separated PBMC subsets, CD4+ and CD8+ T lymphocytes, and CD14+ monocytes under apoptotic stimuli in patients with chronic hepatitis C. Apoptosis was induced by serum starvation and by incubation with anti-CD3 antibody and with phorbol 12-myristate 13-acetate. With the escalating severity of liver disease, susceptibility of all PBMC subsets to apoptosis increased under the apoptotic stimulus of serum starvation (P<0.05). Consequently, increased susceptibility to apoptosis was associated with diminished intracellular expression of the antiapoptotic protein Bcl-2 (P<0.05). The current observations demonstrate that the abnormality of PBMC subsets in undergoing apoptosis as a result of the down-regulation of Bcl-2 expression may contribute to viral persistence and progression of liver disease in chronic hepatitis C.
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PMID:Increased susceptibility to apoptosis and attenuated Bcl-2 expression in T lymphocytes and monocytes from patients with advanced chronic hepatitis C. 1210 Dec 62

Bcl-2 antigen is a proto-oncogene responsible for the inhibition of the death of cells in the mechanism of apoptosis. The expression of bcl-2 antigen was analysed in liver bioptates obtained from patients with chronic hepatitis C. Thirty-five patients with advanced fibrosis (bridging fibrosis or cirrhosis) and various inflammatory activity were investigated. Control group was formed of the subjects with minimum or non-existent fibrosis. Histological and immunohistochemical assessments were performed with the use of widely-acceptable methods. The expression of bcl-2 antigen within portal spaces and lobules was evaluated. The values of lobular index declined as the fibrosis increased. As far as portal space index is concerned, no significant changes in correlation with fibrosis advancement were noticed. Additionally, the expression of bcl-2 antigen was recorded within lymphocyte infiltrations in lobules and portal spaces, in the epithelium of bile ducts in portal spaces and proliferating bile ductules in lobules as well as in perisinusoid cells. In hepatocytes, bcl-2 expression was detected more often among controls than in the analysed patients. The expression of bcl-2 antigen is directly proportional to the degree of inflammatory activity and it is inversely proportional to the degree of fibrosis. It seems that positive colour reaction with bcl-2 antigen in lobules may be of prognostic value for the prediction of collagen fibroplasia development. Bcl-2 expression in portal spaces has a limited diagnostic value for the prediction of the scope of fibrosis in patients with chronic hepatitis C.
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PMID:Bcl-2 antigen expression in patients with chronic hepatitis C and advanced fibrosis. 1221 16

Bcl-2 oncoprotein regulates programmed cell death by providing a survival advantage to rapidly proliferating cells, and bax protein promotes apoptosis by enchanting cell susceptibility to apoptotic stimuli. In this study, we assessed the expression of bcl-2 and bax in liver biopsies from patients with chronic hepatitis (CH) Type B (HBV) and C (HCV). The study comprised 65 liver biopsies from 65 patients with HBV (n = 37) and HCV (n = 28) and 10 normal liver biopsies as controls. The HAI score ranged from 3/18-13/18, and the fibrosis Stage, from 1-6 (7 HBV/10 HCV). Pathologic examination included the following: (1) immunohistochemical stains in paraffin sections for bcl-2 and bax protein expression, (2) Western blot analysis (bcl-2 and bax protein levels evaluation), (3) ISH (detection of bcl-2 and bax mRNA), and (4) ISH (TUNEL-ABI [apoptotic body index]). In CH cases, both bcl-2 and bax protein and mRNA were detected in portal and intralobular lymphocytes and in cholangiolar epithelial cells in interface areas and fibrous bands. Bax protein and mRNA was expressed within hepatocytes and epithelial cells of interlobular ducts in portal tracts. Bcl-2 mRNA was present in periportal hepatocytes only in cases with Stage 5-6 fibrosis. Western blot analysis showed a decreased bcl-2 and an increased bax expression toward advanced fibrotic stages. In CH cases, ABI was reverse correlated with the percentage of bcl-2 expression and was correlated directly with the percentage of bax expression (P <.001). The results of this study suggest that in cases of chronic HBV or HCV infection, bax may be involved in the hepatocyte cycle regulation during infection, whereas its expression in intraportal bile duct epithelium implies that this protein enhances susceptibility of these particular cells to apoptosis. The increased bax expression and ABI in fibrosis Stages 1-5, imply that they are responsible for hepatocytes depletion through apoptosis, during progress of liver fibrosis and fibrous tissue accumulation, until cirrhosis is established. Bcl-2 mRNA expression in periportal hepatocytes only in Stages 5 and 6 suggests that this oncogene is involved in the late stages of progressive liver fibrosis and failure and furthermore that periportal hepatocytes are resistant to apoptosis. Bcl-2 expression, in cholangioles of interface area, suggests that this oncoprotein may be involved in growth regulation of these epithelial cells. Further research is warranted to specify the exact role of apoptosis and apoptotic genes involved in liver fibrosis process in cases of chronic HBV and HCV infection. This may lead to new strategies in the management of human liver disease to prevent the progression to chronic liver failure.
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PMID:Potential role of bcl-2 and bax mRNA and protein expression in chronic hepatitis type B and C: a clinicopathologic study. 1468 29


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