Molecular biological study on the relationship between hepatitis B virus and hepatocellular carcinoma

在这个项目中，我们分析了乙肝病毒(HBVDNA)的复制模式和宿主基因组中不同部分的肝组织和肝细胞癌(HCC)组织之间的整合模式。在一项研究中，我们用Southern杂交技术分析了一名乙肝病毒感染者肝脏中三个肝细胞癌结节(HCCN)的HBVDNA整合模式。我们发现其中一个HCCN的HBVDNA整合模式与另外两个完全不同。我们认为这表明不同的克隆起源，即多中心起源，在这种情况下，肝细胞癌。我们认为这是首次在分子水平上证实肝细胞癌的多中心起源。在接下来的研究中，我们分析了肝硬变(LC)结节之间HBVDNA复制模式和整合模式的差异。在本研究中，我们发现在LC的结节中，HBVDNA的复制模式是异质性的。我们还发现，肝细胞癌结节之间的HBVDNA整合模式是异质性的，而肝细胞癌和肝细胞癌结节之间没有发现共同的整合模式。这些结果表明：1)HBVDNA整合到宿主基因组中，不同的肝硬变结节(LCN)相对于限制性内切酶切点的整合位置不同，可能不同的细胞也不同。2)在某些LCN中，部分整合了HBVDNA的细胞呈克隆性生长。3)在LCN中，HBVDNA的复制并不均匀，单个小样本如活检材料不能代表肝硬变的所有区域。在解释活组织检查材料作为患者病毒复制状态的指示器时，应记住这一现象。

In this project, we analyzed hepatitis B virus (HBV) DNA replication patterns and integration patterns into the host genome among different part of the liver tissues and hepatocellular carcinoma (HCC) tissues. In one investigation, we analyzed HBV DNA integration patterns of three hepatocellular carcinoma nodules (HCCN) in the liver of a HBV infected patient by Southern blot hybridization. We found HBV DNA integration pattern of one HCCN was completely different from those of other two. We think this indicates different clonal origin, i.e. multicentric origin, of HCC in this case. We believe this is the first confirmation of multicentric origin of HCC at molecular level. In the next investigation, we analyzed the difference of HBV DNA replication patterns and integration patterns among the nodules of the liver cirrhosis (LC). In this investigation, we found the HBV DNA replication patterns are heterogeneous among the nodules of LC. We also found HBV DNA integration patterns among the nodules of LC are heterogeneous and no common integration patterns are found among the nodules of LC and HCC. These results indicate: 1) HBV DNA integrates into the host genome and integration sites relative to the restriction enzyme cutting sites are different from one liver cirrhosis nodules (LCN) to another and probably different from one cell to another. 2) In some LCN, some of these cells with integrated HBV DNA grow clonally. 3) Replication of HBV DNA is not homogeneous among LCN and one small specimen such as biopsy materials cannot represent every areas of the cirrhotic liver. This phenomenon should be kept in mind in the interpretation of the biopsy material as an indicator of virus replication state of a patient.