人肝细胞癌相关新基因的筛选

Screening of novel hepatocellular carcinoma associated genes

目的 :寻找肝细胞癌 (hepatocellularcarcinoma ,HCC)相关的新基因 ,并从分子水平进一步探讨HCC发生发展的机制。方法 :对通过荧光 差异显示 (fluorescent differentialdisplay ,FluoroDD)技术从人HCC组织、配对非癌肝 ( pairednon cancerousliver,PNL)组织、胎肝 (fetalliver ,FL)组织和正常肝 (normalliver ,NL)组织获得的 110条差异表达cDNA片段 (DD片段 )中的 2 5条进行测序 ,将测序结果在GenBankNR数据库中进行同源性分析 ,并对其中 12条DD片段用RNA狭缝杂交法验证其在HCC、PNL及NL组织中的表达规律。结果 :2 5条DD片段中 18条与已知基因具有高同源性 ( >96 % ) ;5条与已知序列 (基因结构与功能未知 )具有高同源性 ( >85 % ) ;2条与Gen BankNR数据库中的序列无明显同源性。RNA狭缝杂交筛选到 5条在HCC中特异性高或低表达并与已知哺乳类动物基因高度同源 ( 97%～ 99% )的cDNA片段 :在HCC中特异性高表达的 3条片段是LC13(人热休克蛋白 90 β)、LC2 1(智人异源性核内核糖核蛋白C)和LC2 2 (干扰素诱导的智人鸟嘌呤结合蛋白 2 ) ;在HCC中特异性低表达的 2条片段是LC5 (智人甲状腺激素受体相关蛋白 2 40 )和FL2 5 (分化相关基因 1)。结论 :新发现 5条与HCC相关、与已知哺乳动物基因高度同源的cDNA片段。

Objective: To screen novel hepatocellular carcinoma (HCC) associated genes. Methods: 25 differentially expressed cDNA fragments (DD fragments) that came from comparison of human HCC, paired non cancerous liver, fetal liver and normal liver tissues by fluorescent differential display (Fluoro DD) were sequenced. Among them, expression patterns of 12 cDNA were detected by RNA slot blot hybridization. Results: Among 25 DD fragments sequenced, 18 fragments showed highly homologous to known genes, 5 fragments showed highly homologous to known sequences (with unknown gene structure and function) and 2 fragments showed unknown sequences in GenBank NR database. The results from RNA slot blot hybridization showed that the transcriptions of LC13 (99% identity with human 90 kDa heat shock protein beta, HSP90β mRNA), LC21(99% identity with homo sapiens heterogeneous nuclear ribonucleoprotein C, hnRNP C mRNA) and LC22(99% identity with homo sapiens interferon inducible guanylate binding protein 2, GBP2 mRNA) were up regulated in most HCCs. However, the transcriptions of LC5(99% identity with homo sapiens thyroid hormone receptor associated protein 240, TRAP240 mRNA ) and FL25 ( 97% identity with differentiation related gene 1, drg1) were down regulated in most HCCs. Conclusion: Five HCC associated genes were identified. They may act as the candidates for HCC promotion or suppression associated genes.