title: Upregulated expression of a unique gene by hepatitis B x antigen promotes hepatocellular growth and tumorigenesis.
abstract: Hepatitis B x antigen (HB x Ag) is a trans-activating protein that may be involved in hepatocarcinogenesis, although few natural effectors of HB x Ag that participate in this process have been identified. To identify additional effectors, whole cell RNA isolated from HB x Ag-positive and HB x Ag-negative HepG2 cells were compared by polymerase chain reaction select cDNA subtraction, and one clone, upregulated gene, clone 11 (URG11), was chosen for further characterization. Elevated levels of URG11 mRNA and protein were observed in HB x Ag-positive compared to HB x Ag-negative HepG2 cells. Costaining was observed in infected liver (P < 0.01). URG11 stimulated cell growth in culture (P < 0.01), anchorage-independent growth in soft agar (P < 0.001), and accelerated tumor formation (P < 0.01), and yielded larger tumors (P < 0.02) in SCID mice injected subcutaneously with HepG2 cells. These data suggest that URG11 is a natural effector of HB x Ag that may promote the development of hepatocellular carcinoma.
authors.affiliation: Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
authors.forename: Zhaorui
authors.initials: Z
authors.lastname: Lian
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.forename: Xianxing
authors.initials: X
authors.lastname: Li
authors.forename: N Lale Satiroglu
authors.initials: NL
authors.lastname: Tufan
authors.forename: Marcy
authors.initials: M
authors.lastname: Clayton
authors.forename: Meng-Chao
authors.initials: MC
authors.lastname: Wu
authors.forename: Hong-Yang
authors.initials: HY
authors.lastname: Wang
authors.forename: Patrick
authors.initials: P
authors.lastname: Arbuthnot
authors.forename: Michael
authors.initials: M
authors.lastname: Kew
authors.forename: Mark A
authors.initials: MA
authors.lastname: Feitelson
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D003001:Cloning, Molecular; D015972:Gene Expression Regulation, Neoplastic; D015967:Gene Expression Regulation, Viral; D006511:Hepatitis B Antigens / Q000502:physiology*; D006515:Hepatitis B virus / Q000235:genetics; D006801:Humans; D017403:In Situ Hybridization; D008114:Liver Neoplasms, Experimental / Q000821:virology*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000032:analysis*; D015533:Transcriptional Activation; D014162:Transfection; D014407:Tumor Cells, Cultured; D015854:Up-Regulation
chemical_list: D006511:Hepatitis B Antigens; D012333:RNA, Messenger