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)

Promyelocytic leukemia protein (PML) is a major component of PML nuclear bodies (PML NBs). Fusion of promyelocytic leukemia alpha gene (PML) with retinoic acid receptor gene with the t (15;17) translocation causes disassembly of PML NBs, leading to development of acute promyelocytic leukemia. In contrast, PML overexpression as well as different morphological changes of PML NBs were described in a few solid tumors. In this study, the expression of PML through the multistep hepatocarcinogenesis was analyzed in 95 cases of human hepatocellular carcinomas (HCCs) for comparison along with dysplastic nodules (DNs) and background liver cirrhosis (LC) or chronic hepatitis by immunohistochemistry and immunoblot. In addition, cases of HCCs were further evaluated according to their histologic grade and etiology. The amount of PML as well as the number and size of PML NBs increased gradually through the progression from LC, DNs to HCCs. The overexpression of PML in HCCs was much more closely associated with HBV infection than HCV infection or alcoholic liver disease. The PML expression, however, was not correlated with histologic grade of HCCs. These results suggest that PML is involved in the early stage of multistep hepatocarcinogenesis, and HBV infection may be associated with the overexpression of PML and the morphological alteration of PML NBs.
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PMID:Overexpression of promyelocytic leukemia protein and alteration of PML nuclear bodies in early stage of hepatocarcinogenesis. 1151 88

Promyelocytic leukemia nuclear bodies (PML-NB) are sub-nuclear organelles that are the hub of numerous proteins. DNA/RNA viruses often hijack the cellular factors resident in PML-NBs to promote their proliferation in host cells. Hepatitis B virus (HBV), belonging to Hepadnaviridae family, remains undetected in early infection as it does not induce the innate immune response and is known to be the cause of several hepatic diseases leading to cirrhosis and hepatocellular carcinoma. The association of PML-NB proteins and HBV is being addressed in a number of recent studies. Here, we report that the PML-NB protein Speckled 110 kDa (Sp110) is SUMO1-modified and undergoes a deSUMOylation-driven release from the PML-NB in the presence of HBV. Intriguingly, Sp110 knockdown significantly reduced viral DNA load in the culture supernatant by activation of the type I interferon-response pathway. Furthermore, we found that Sp110 differentially regulates several direct target genes of hepatitis B virus protein X (HBx), a viral co-factor. Subsequently, we identified Sp110 as a novel interactor of HBx and found this association to be essential for the exit of Sp110 from the PML-NB during HBV infection and HBx recruitment on the promoter of these genes. HBx, in turn, modulates the recruitment of its associated transcription cofactors p300/HDAC1 to these co-regulated genes, thereby altering the host gene expression program in favor of viral persistence. Thus, we report a mechanism by which HBV can evade host immune response by hijacking the PML-NB protein Sp110, and therefore, we propose it to be a novel target for antiviral therapy.
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PMID:Host transcription factor Speckled 110 kDa (Sp110), a nuclear body protein, is hijacked by hepatitis B virus protein X for viral persistence. 2904 50