Thelu M A, Zarski J P, Froissart B, Rachail M, Seigneurin J M
Clinique d'Hépato-Gastroentérologie, CHRU, Grenoble.
Gastroenterol Clin Biol. 1993;17(12):903-7.
It has been observed that certain rare alleles of the c-Ha-ras gene occur more frequently in patients with certain malignant tumors than in healthy individuals, suggesting that these alleles may serve as markers for particular types of cancer. In this study, we compared the restriction fragment length polymorphism at the c-Ha-ras gene locus in 40 patients with cirrhosis and hepatocellular carcinoma with that in 39 patients with cirrhosis and in 42 normal subjects, all of Caucasian origin. Southern blotting of leukocyte DNA from the above patients, after digestion with either BamH1 or AvaII, revealed the presence of allele fragments of different sizes, corresponding to 4 common alleles and 3 rare alleles. The occurrence of the 3 rare alleles was not significantly different in the 3 populations studied. On the other hand, 2 of the common alleles, a3 (P < 0.01) and a4 (P < 0.03), were found at a significantly higher frequency in patients with cancer than in the 2 other groups. These results suggest that, in hepatocellular carcinoma, there is no increase in the frequency of occurrence of the rare alleles of the c-Ha-ras, but that the distribution of the common alleles may be modified.
据观察，c-Ha-ras基因的某些罕见等位基因在某些恶性肿瘤患者中出现的频率高于健康个体，这表明这些等位基因可能作为特定类型癌症的标志物。在本研究中，我们比较了40例肝硬化和肝细胞癌患者、39例肝硬化患者以及42例正常受试者（均为白种人）c-Ha-ras基因位点的限制性片段长度多态性。用BamH1或AvaII消化上述患者的白细胞DNA后进行Southern印迹分析，结果显示存在不同大小的等位基因片段，对应于4种常见等位基因和3种罕见等位基因。在所研究的3组人群中，3种罕见等位基因的出现频率没有显著差异。另一方面，2种常见等位基因a3（P < 0.01）和a4（P < 0.03）在癌症患者中的出现频率显著高于其他2组。这些结果表明，在肝细胞癌中，c-Ha-ras罕见等位基因的出现频率没有增加，但常见等位基因的分布可能会发生改变。
