Ochiya T, Matsubara K
Gan To Kagaku Ryoho. 1987 Jun;14(6 Pt 2):2164-9.
Primary human hepatocellular carcinomas (HCC) were surveyed for oncogenes by transformation assays using NIH3T3 cells and the calcium phosphate coprecipitation method. High-molecular-weight DNA obtained from the HCC tissues was employed for this purpose. One new transforming DNA, named lca (for liver cancer) was obtained, and its properties were studied in detail. This transforming DNA had a linkage to the Alu sequence and was cloned in lambda phage. Restriction enzyme analyses showed that the minimum size of the lca DNA is about 10.5 kilobase pairs and that its nucleotide sequence is different from that of any known human gene or retroviral oncogene. Southern blot analyses of DNAs from flow-sorted human chromosomes and human-mouse somatic cell hybrids indicated that the lca DNA is located on human chromosome 2. It showed identical restriction enzyme cleavage profiles with its counterpart DNA obtained from normal tissue, indicating that there is no extensive DNA rearrangement associated with the activation process of the lca DNA. The normal counterpart DNA shows no transforming activity. An independently obtained transforming DNA from another HCC exhibited identical restriction enzyme cleavage profiles. Thus, lca DNA is likely to represent a commonly encountered transforming DNA in HCC.
利用NIH3T3细胞和磷酸钙共沉淀法，通过转化试验对原发性人肝细胞癌（HCC）中的癌基因进行了检测。为此，采用了从HCC组织中获得的高分子量DNA。获得了一种名为lca（肝癌相关）的新转化DNA，并对其特性进行了详细研究。这种转化DNA与Alu序列相关，并克隆到λ噬菌体中。限制性内切酶分析表明，lca DNA的最小大小约为10.5千碱基对，其核苷酸序列与任何已知的人类基因或逆转录病毒癌基因均不同。对流式分选的人类染色体和人-鼠体细胞杂种的DNA进行Southern印迹分析表明，lca DNA位于人类2号染色体上。它与其从正常组织获得的对应DNA显示出相同的限制性内切酶切割图谱，表明在lca DNA的激活过程中不存在广泛的DNA重排。正常的对应DNA没有转化活性。从另一个HCC独立获得的转化DNA显示出相同的限制性内切酶切割图谱。因此，lca DNA可能代表HCC中常见的转化DNA。
