原发性肝细胞癌中HBV DNA整合位点分析

Analysis on hepatitis B virus(HBV) DNA integration sites in primary hepatocellular carcinomas(HCC)

目的比较乙型肝炎病毒(HBV)基因在原发性肝细胞癌及癌旁组织中的整合规律,探讨其致癌作用机制。方法采用Alu-PCR和LM-PCR方法扩增50例有慢性HBV感染背景的肝癌组织及配对非肿瘤肝组织的HBV整合片段,并对整合位点侧翼的病毒及人基因组DNA序列进行测序,通过NCBIBIAST及UCSCBLAT检索确定HBVDNA在染色体上的精确整合位置。结果 50例肝癌组织中有34例标本检测到HBVDNA的整合,癌组织HBVDNA的整合检出率为68%;配对癌旁组织有35例标本检测到HBVDNA的整合,整合检出率为70%。癌组织中的所有染色体上都检测到HBV整合位点,癌旁组织中除了Y染色体之外,其余染色体也都检测到整合位点。其中14号、15号、18号、19号、Y染色体的HBVDNA整合密度在癌组织中高于癌旁组织。结论癌组织中14号、15号、18号、19号和Y染色体的HBVDNA整合频率高于癌旁组织,整合位点附近有与癌症相关的基因,提示HBVDNA在这些染色体上的整合可能与HBV致癌机制有一定相关性。

Subject It has been known that hepatitis B virus(HBV) DNA integrates into or close to human genes in primary hepatocellular carcinomas(HCC) and peficancerous tissues frequently.Our research aims at figuring out its regulations and carcinogenesis.Methods Alu-PCR and LM-PCR are adopted to amplify the HBV integration sequences and its flank sequences of human.After full-automatic sequencing,we analyze the data by NCBI BLAST and UCSC BLAT to locate the exact integration sites.Results 34/50(68%) cancer tissues were found with HBV DNA integration and 35/50(70%) in matched perficancerous tissues.Integration was detected in all the chromosomes in cancer tissues while almost all in matched perficancerous tissues with exception of Y chromosome.Specifically,the frequency of HBV DNA integration in chromosome 14,15,18,19 were obviously higher in cancer tissues.Conclusions The frequencies of HBV DNA integrations in chromosome 14,15,18,19 and Y were higher in cancer tissues.The genes in or closed to those integration sites are related to hepatocellular carcinogenesis.HBV DNA integration induced chromosome instability may be an important factor for HBV carcinogenesis.