IDENTIFICATION OF INTEGRATED HEPATITIS-B VIRUS-DNA AND EXPRESSION OF VIRAL-RNA IN AN HBSAG-PRODUCING HUMAN HEPATOCELLULAR-CARCINOMA CELL-LINE
IDENTIFICATION OF INTEGRATED HEPATITIS-B VIRUS-DNA AND EXPRESSION OF VIRAL-RNA IN AN HBSAG-PRODUCING HUMAN HEPATOCELLULAR-CARCINOMA CELL-LINE
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DOI：
10.1038/286531a0
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发表时间：
1980-01-01
期刊：
影响因子：
64.8
通讯作者：
SHAFRITZ, DA
中科院分区：
文献类型：
--
作者：
CHAKRABORTY, PR;RUIZOPAZO, N;SHAFRITZ, DA
Alexander 及其同事从一名乙型肝炎病毒表面抗原 (HBsAg) 血清呈阳性的莫桑比克男性原发性肝细胞癌中开发了一种组织培养细胞系 (PLC/PRF/5)。该细胞系产生并分泌 HBsAg，但不产生其他已知的病毒蛋白1-3。因此，PLC/PRF/5 至少包含部分功能形式的乙型肝炎病毒 (HBV) 基因组。人血清中的 42 nm 球形 Dane 颗粒被认为代表了 HBV4 的完整传染源。该颗粒的核心包含环状双链 DNA，其中一条链带有“切口”（完整但未共价闭合），另一条链不完整（缺少 15-45% 的序列互补体）4,5。四种蛋白质与 HBsAg、核心抗原 (HBcAg)、e 抗原和病毒 DNA 聚合酶4 相关。目前，多个研究小组已经在大肠杆菌 6-10 中克隆了 Dane 颗粒 DNA，并且已经确定了限制性图谱和完整的 DNA 序列。各种研究表明，从表达相同或不同病毒亚型的患者中分离的 Dane 颗粒 DNA 存在序列异质性，以及从给定个体获得的 Dane 颗粒 DNA 的不同克隆中存在序列变异10,11。其他研究 12,13 报道了肝癌组织 DNA 中的 HBV DNA 序列。在这些情况下，病毒 DNA 均未整合到宿主细胞基因组中。随着表征病毒DNA分子的技术的改进，我们已经开始通过细胞DNA和RNA与克隆的32P标记的质粒HBV DNA的分子杂交来分析HBV基因及其在PLC/PRF/5细胞系中的表达。我们现在在 PLC/PRF/5 细胞中提供证据，证明 HBV DNA 整合到宿主基因组中，并表达三种含有 HBV 特异性序列的 RNA 分子。这些发现与在几种动物病毒模型中观察到的结果一致，在这些模型中，在致癌转化过程中发现了整合的病毒DNA。
Alexander and co-workers1have developed a tissue culture cell line (PLC/PRF/5) from a primary hepatocellular carcinoma of a Mozambican male with a positive serum for hepatitis B virus surface antigen (HBsAg). This cell line produces and secretes HBsAg but no other known viral protein1–3. PLC/PRF/5 therefore contains at least part of the hepatitis B virus (HBV) genome in functional form. The 42-nm, spherical Dane particle in human serum is thought to represent the complete infectious agent of HBV4. The core of this particle contains circular double-stranded DNA in which one strand is ‘nicked’ (complete but not covalently closed) and the other strand is incomplete (lacking 15–45% of its sequence complement)4,5. Four proteins have been associated with the HBsAg, core antigen (HBcAg), e antigen and a viral DNA polymerase4. Several groups have now cloned Dane particle DNA inEscherichia coli6–10, and both restriction maps and a complete DNA sequence have been determined. Various studies suggest that there is sequence heterogeneity in Dane particle DNA isolated from patients expressing the same or different viral subtypes, as well as sequence variation in different clones of Dane particle DNA obtained from a given individual10,11. Other studies12,13have reported HBV DNA sequences in DNA from liver cancer tissue. In none of these cases was viral DNA reported to be integrated into the host cell genome. With the improvement in techniques for characterizing viral DNA molecules, we have begun to analyse HBV genes and their expression in the PLC/PRF/5 cell line by molecular hybridization of cellular DNA and RNA to cloned32P-labelled plasmid HBV DNA. We now present evidence in PLC/PRF/5 cells for integration of HBV DNA into the host genome and expression of three RNA molecules containing HBV-specific sequences. These findings are consistent with observations in several animal virus models in which integrated viral DNA is found during oncogenic transformation.