肝癌内高表达新基因的部分cDNA克隆

The partial cDNA cloning of a novel gene highly expressed in hepatocellular carcinoma

目的寻找人肝癌相关的基因。方法应用Ｎｏｒｔｈｅｒｎ杂交技术，对表达序列标记（ＥｘｐｒｅｓｓｅｄＳｅ－ｑｕｅｎｃｅｔａｇｓ，ＥＳＴ）基因克隆进行筛选，以得到的基因片段为探针，筛选人胎肝ｃＤＮＡ文库。结果得到一个在肝癌内高表达的ＥＳＴ基因片段。进一步筛选人胎肝ｃＤＮＡ文库，得到一命名为ＦＬ６的ｃＤ－ＮＡ克隆，核苷酸序列测定表明，ＦＬ６长度为１４６４个碱基，检索最新版本ＧｅｎｅＤａｔａｂａｓｅｓ（ＥＭＢＬ９６．６），未发现同源基因。实验结果还显示该基因在胎儿各组织内有不同的表达特性。结论该基因可能与细胞的增殖、癌变过程相关。

Objective To search the novel gene related to human hepatoma. Methods Northern blot analysis was used to isolate from EST (expressed sequence tags) clones a cDNA fragment differentially expressed in hepatocellular carcinoma versus its surrounding noncancerous hepatic tissue. Human fetal liver cDNA library was screened with EST fragment probe. Results Northern blot analysis showed that EST clone F9391 expressed at high level in all the 6 hepatocellular carcinoma samples but low level in the surrounding noncancerous hepatic tissues and 2 normal liver tissues. In further screening of human fetal liver cDNA libary, we obtained a positive clone named FL6. Nucleotide sequencing indicated that FL6 contained 1464 base pairs and the matched DNA sequence was not found in the gene data bases (EMBL 96.6). Northern blot analysis of various fetus tissues with FL6 probe showed a high level expression in lung, small intestine, skin and placenta, middle level expression in liver, stomach, colon and muscle; but low level expression in brain, thyroid, thymus, heart, kidney, pancreas and bladder. Conclusion The results suggested that FL6 gene ralated to cell proliferation and may play an important role in the process of oncogenesis.