McLellan E A, Owen R A, Stepniewska K A, Sheffield J P, Lemoine N R
Molecular Pathology Laboratory, Royal Postgraduate Medical School, Hammersmith Hospital, London.
Gut. 1993 Mar;34(3):392-6. doi: 10.1136/gut.34.3.392.
The frequency of activating mutations at codons 12 and 13 of the K-ras gene was investigated in 57 sporadic adenomas from 47 patients using the polymerase chain reaction and oligonucleotide hybridisation assay. Sixty eight per cent of the adenomas tested were positive for K-ras mutations. This high frequency, combined with the lack of a correlation between mutations and adenoma size, suggest that K-ras mutations occur earlier in the adenoma-carcinoma sequence than has previously been suggested. The high frequency observed in sporadic adenomas contrasts with the reported low frequency (18%) in adenomas from patients with familial adenomatous polyposis (FAP), suggesting a possible difference in the molecular genesis of FAP and non-FAP adenomas. Finally, it was found that adenomas from patients with a personal history of colorectal cancer were more likely to contain a K-ras mutation than those from patients with no such history. This is a new finding and worthy of further study.
采用聚合酶链反应和寡核苷酸杂交分析法，对47例患者的57个散发性腺瘤中K-ras基因第12和13密码子激活突变的频率进行了研究。检测的腺瘤中有68%的K-ras突变呈阳性。这一高频率，再加上突变与腺瘤大小之间缺乏相关性，表明K-ras突变在腺瘤-癌序列中出现的时间比之前认为的更早。在散发性腺瘤中观察到的高频率与家族性腺瘤性息肉病（FAP）患者腺瘤中报道的低频率（18%）形成对比，提示FAP和非FAP腺瘤在分子发生机制上可能存在差异。最后，发现有结直肠癌个人病史的患者的腺瘤比无此类病史患者的腺瘤更有可能含有K-ras突变。这是一项新发现，值得进一步研究。
