Publications by authors named "Lusheng Que"

7 Publications

  • Page 1 of 1

Identification of natural compounds extracted from crude drugs as novel inhibitors of hepatitis C virus.

Biochem Biophys Res Commun 2021 Aug 12;567:1-8. Epub 2021 Jun 12.

Department of Virology II, National Institute of Infectious Diseases, 162-8640, Tokyo, Japan. Electronic address:

Natural product-derived crude drugs are expected to yield an abundance of new drugs to treat infectious diseases. Hepatitis C virus (HCV) is an oncogenic virus that significantly impacts public health. In this study, we sought to identify anti-HCV compounds in extracts of natural products. A total of 110 natural compounds extracted from several herbal medicine plants were examined for antiviral activity against HCV. Using a Huh7-mCherry-NLS-IPS reporter system for HCV infection, we first performed a rapid screening for anti-HCV compounds extracted from crude drugs. The compounds threo-2,3-bis(4-hydroxy-3-methoxyphenyl)-3-butoxypropan-1-ol (#106) and medioresinol (#110), which were extracted from Crataegus cuneate, exhibited anti-HCV activity and significantly inhibited HCV production in a dose-dependent manner. Analyses using HCV pseudoparticle and subgenomic replicon systems indicated that compounds #106 and #110 specifically inhibit HCV RNA replication but not viral entry or translation. Interestingly, compound #106 also inhibited the replication and production of hepatitis A virus. Our findings suggest that C. cuneate is a new source for novel anti-hepatitis virus drug development.
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http://dx.doi.org/10.1016/j.bbrc.2021.06.022DOI Listing
August 2021

MCPIP1 reduces HBV-RNA by targeting its epsilon structure.

Sci Rep 2020 11 27;10(1):20763. Epub 2020 Nov 27.

Department of Molecular Genetics, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa, 920-8640, Japan.

Hepatitis B virus (HBV) is the major causative factor of chronic viral hepatitis, liver cirrhosis, and hepatocellular carcinoma. We previously demonstrated that a proinflammatory cytokine IL-1β reduced the level of HBV RNA. However, the mechanism underlying IL-1β-mediated viral RNA reduction remains incompletely understood. In this study, we report that immune regulator Monocyte chemotactic protein-1-induced protein 1 (MCPIP1) can reduce HBV RNA in hepatocytes. MCPIP1 expression level was higher in the liver tissue of HBV-infected patients and mice. Overexpression of MCPIP1 decreased HBV RNA, whereas ablating MCPIP1 in vitro enhanced HBV production. The domains responsible for RNase activity or oligomerization, were required for MCPIP1-mediated viral RNA reduction. The epsilon structure of HBV RNA was important for its antiviral activity and cleaved by MCPIP1 in the cell-free system. Lastly, knocking out MCPIP1 attenuated the anti-HBV effect of IL-1β, suggesting that MCPIP1 is required for IL-1β-mediated HBV RNA reduction. Overall, these results suggest that MCPIP1 may be involved in the antiviral effect downstream of IL-1β.
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http://dx.doi.org/10.1038/s41598-020-77166-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7699622PMC
November 2020

EBV-LMP1 induces APOBEC3s and mitochondrial DNA hypermutation in nasopharyngeal cancer.

Cancer Med 2020 10 20;9(20):7663-7671. Epub 2020 Aug 20.

Division of Otorhinolaryngology and Head and Neck Surgery, Kanazawa University, Kanazawa, Japan.

An Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1) is a principal oncogene that plays a pivotal role in EBV-associated malignant tumors including nasopharyngeal cancer (NPC). Recent genomic landscape studies revealed that NPC also contained many genomic mutations, suggesting the role of LMP1 as a driver gene for the induction of these genomic mutations. Nonetheless, its exact mechanism has not been investigated. In this study, we report that LMP1 alters the expression profile of APOBEC3s(A3s), host deaminases that introduce consecutive C-to-U mutations (hypermutation). In vitro, LMP1 induces APOBEC3B (A3B) and 3F(A3F), in a nasopharyngeal cell line, AdAH. Overexpression of LMP1, A3B, or A3F induces mtDNA hypermutation, which is also detectable from NPC specimens. Expression of LMP1 and A3B in NPC was correlated with neck metastasis. These results provide evidence as to which LMP1 induces A3s and mtDNA hypermutation, and how LMP1 facilitates metastasis is also discussed.
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http://dx.doi.org/10.1002/cam4.3357DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7571841PMC
October 2020

Different antiviral activities of natural APOBEC3C, APOBEC3G, and APOBEC3H variants against hepatitis B virus.

Biochem Biophys Res Commun 2019 10 7;518(1):26-31. Epub 2019 Aug 7.

Department of Molecular Genetics, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan. Electronic address:

Some APOBEC3 family members have antiviral activity against retroviruses and DNA viruses. Hepatitis B virus (HBV) is a DNA virus that is the major causative factor of severe liver diseases such as cirrhosis and hepatocellular carcinoma. To determine whether APOBEC3 variants in humans have different anti-HBV activities, we evaluated natural variants of APOBEC3C, APOBEC3G, and APOBEC3H using an HBV-replicating cell culture model. Our data demonstrate that the APOBEC3C variant S188I had increased restriction activity and hypermutation frequency against HBV DNA. In contrast, the APOBEC3G variant H186R did not alter the anti-HBV and hypermutation activities. Among APOBEC3H polymorphisms (hap I-VII) and splicing variants (SV-200, SV-183, SV-182, and SV-154), hap II SV-183 showed the strongest restriction activity. These data suggest that the genetic variations in APOBEC3 genes may affect the efficiency of HBV elimination in humans.
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http://dx.doi.org/10.1016/j.bbrc.2019.08.003DOI Listing
October 2019

Keratinocyte differentiation induces APOBEC3A, 3B, and mitochondrial DNA hypermutation.

Sci Rep 2018 06 27;8(1):9745. Epub 2018 Jun 27.

Department of Molecular Genetics, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa, 920-8640, Japan.

Mitochondrial DNA (mtDNA) mutations are found in many types of cancers and suspected to be involved in carcinogenesis, although the mechanism has not been elucidated. In this study, we report that consecutive C-to-T mutations (hypermutations), a unique feature of mutations induced by APOBECs, are found in mtDNA from cervical dysplasia and oropharyngeal cancers. In vitro, we found that APOBEC3A (A3A) and 3B (A3B) expression, as well as mtDNA hypermutation, were induced in a cervical dysplastic cell line W12 when cultured in a differentiating condition. The ectopic expression of A3A or A3B was sufficient to hypermutate mtDNA. Fractionation of W12 cell lysates and immunocytochemical analysis revealed that A3A and A3B could be contained in mitochondrion. These results suggest that mtDNA hypermutation is induced upon keratinocyte differentiation, and shed light on its molecular mechanism, which involves A3s. The possible involvement of mtDNA hypermutations in carcinogenesis is also discussed.
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http://dx.doi.org/10.1038/s41598-018-27930-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6021414PMC
June 2018

Flap endonuclease 1 is involved in cccDNA formation in the hepatitis B virus.

PLoS Pathog 2018 06 21;14(6):e1007124. Epub 2018 Jun 21.

Department of Molecular Genetics, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan.

Hepatitis B virus (HBV) is one of the major etiological pathogens for liver cirrhosis and hepatocellular carcinoma. Chronic HBV infection is a key factor in these severe liver diseases. During infection, HBV forms a nuclear viral episome in the form of covalently closed circular DNA (cccDNA). Current therapies are not able to efficiently eliminate cccDNA from infected hepatocytes. cccDNA is a master template for viral replication that is formed by the conversion of its precursor, relaxed circular DNA (rcDNA). However, the host factors critical for cccDNA formation remain to be determined. Here, we assessed whether one potential host factor, flap structure-specific endonuclease 1 (FEN1), is involved in cleavage of the flap-like structure in rcDNA. In a cell culture HBV model (Hep38.7-Tet), expression and activity of FEN1 were reduced by siRNA, shRNA, CRISPR/Cas9-mediated genome editing, and a FEN1 inhibitor. These reductions in FEN1 expression and activity did not affect nucleocapsid DNA (NC-DNA) production, but did reduce cccDNA levels in Hep38.7-Tet cells. Exogenous overexpression of wild-type FEN1 rescued the reduced cccDNA production in FEN1-depleted Hep38.7-Tet cells. Anti-FEN1 immunoprecipitation revealed the binding of FEN1 to HBV DNA. An in vitro FEN activity assay demonstrated cleavage of 5'-flap from a synthesized HBV DNA substrate. Furthermore, cccDNA was generated in vitro when purified rcDNA was incubated with recombinant FEN1, DNA polymerase, and DNA ligase. Importantly, FEN1 was required for the in vitro cccDNA formation assay. These results demonstrate that FEN1 is involved in HBV cccDNA formation in cell culture system, and that FEN1, DNA polymerase, and ligase activities are sufficient to convert rcDNA into cccDNA in vitro.
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http://dx.doi.org/10.1371/journal.ppat.1007124DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6013022PMC
June 2018

Molecular characterization of AID-mediated reduction of hepatitis B virus transcripts.

Virology 2017 10 2;510:281-288. Epub 2017 Aug 2.

Department of Molecular Genetics, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan. Electronic address:

Hepatitis B virus (HBV) is the major cause of liver cirrhosis and hepatocellular carcinoma. After entering a hepatocyte, HBV forms a nuclear viral episome and produces pregenomic (pg) RNA with a stem-loop structure called an epsilon, which acts to signal encapsidation. We previously demonstrated that TGF-β upregulates activation-induced cytidine deaminase (AID) expression in hepatocytes, which in turn downregulates HBV transcripts by recruiting the RNA exosome complex. The molecular mechanism underlying AID-mediated HBV RNA reduction remains largely unclear. Here we used a pgRNA reporter system having a reporter gene within pgRNA to identify sis- and trans-acting elements in AID-mediated HBV RNA reduction. We found that the epsilon RNA and C-terminus of AID are required for AID-mediated HBV RNA reduction. Importantly, this reduction was reproduced in a hydrodynamic HBV transfection mouse model. The molecular mechanism of AID-mediated HBV RNA reduction is discussed.
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http://dx.doi.org/10.1016/j.virol.2017.07.035DOI Listing
October 2017