Direct sequencing analysis of exon 1 of the c-K-ras gene shows a low frequency of mutations in human pancreatic adenocarcinomas.
Direct sequencing analysis of exon 1 of the c-K-ras gene shows a low frequency of mutations in human pancreatic adenocarcinomas.
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发表时间：
1989-09
期刊：
影响因子：
8
通讯作者：
N. Gonzalez-Cadavid;D. Zhou;H. Battifora;M. Bar‐eli;M. Cline
中科院分区：
文献类型：
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作者：
N. Gonzalez-Cadavid;D. Zhou;H. Battifora;M. Bar‐eli;M. Cline
我们应用聚合酶链式反应体外扩增的 DNA 片段的直接双脱氧测序来检测人胰腺腺癌中 c-K-ras 基因外显子 1 的突变。对四个新鲜冷冻的原发性肿瘤、一个转移性肿瘤和十二个福尔马林固定石蜡包埋的肿瘤进行了分析。在一小群细胞中，只有 3 个病例显示出密码子 12 可能存在突变，而通过 RNAase A 保护测定和等位基因特异性寡核苷酸杂交报道的这种改变的频率很高。 DNA 序列分析和后一种方法在灵敏度上没有发现重大差异。我们的结果表明，如果 c-K-ras 突变确实以其他人报道的高频率存在于胰腺腺癌中，那么它们必须局限于细胞群的一小部分，以避免直接测序检测到。这种现象可能对胰腺癌发病机制中的 c-K-ras 突变产生影响。
We have applied direct dideoxy sequencing of DNA fragments amplified in vitro by the polymerase chain reaction to the detection of mutations in exon 1 of the c-K-ras gene in human pancreatic adenocarcinomas. Four fresh frozen primary tumors, one metastatic tumor, and twelve formalin-fixed paraffin embedded tumors were analysed. Only three cases showed a possible mutation in codon 12 in a small population of cells, in contrast to the high frequency reported for this alteration with the RNAase A protection assay and allele-specific oligoxynucleotide hybridization. No major difference in sensitivity was found between DNA sequence analysis, and the latter method. Our results suggest that if c-K-ras mutations are indeed present in pancreatic adenocarcinomas at the high frequency reported by others, they must be confined to a small fraction of the cell population to escape detection by direct sequencing. Such a phenomenon would have implications for c-K-ras mutations in the pathogenesis of pancreatic adenocarcinomas.