Lin S Y, Chen P H, Yang M J, Chen T C, Chang C P, Chang J G
Department of Molecular Medicine and Clinical Pathology, Taipei Municipal Jen-Ai Hospital, Taiwan, ROC.
J Gastroenterol Hepatol. 1995 Mar-Apr;10(2):119-24. doi: 10.1111/j.1440-1746.1995.tb01064.x.
Ras oncogene and p53 gene mutations are frequently observed in colorectal cancers. The role of co-operation between these two genes in the tumorigenesis of colorectal cancer was evaluated. Point mutations in K-ras oncogene and hotspot codons of p53 gene of colorectal cancers were evaluated by naturally created or amplified created restriction site method. Nine of 42 cases (21.4%) of colorectal cancer showed K-ras oncogene mutations. Six of 42 cases (14.3%) of colorectal cancer showed p53 gene hotspot point mutations. The low frequency of p53 gene mutation in this series may be due to racial difference or different hotspot codons. When six cases with mutated p53 gene were examined, only one (16.7%) showed concurrent K-ras oncogene codon 12 and p53 gene codon 248 mutations. We concluded that the co-operation between ras oncogene and p53 gene hotspot point mutations in the tumorigenesis of colorectal cancer in Chinese was not common. Other factors such as adenomatous polyposis coli gene mutations, oncogene activation or tumour suppression gene inactivation may be involved.
Ras癌基因和p53基因突变在结直肠癌中经常被观察到。评估了这两个基因之间的协同作用在结直肠癌发生中的作用。采用自然产生或扩增产生的限制性位点方法评估结直肠癌K-ras癌基因的点突变和p53基因的热点密码子。42例结直肠癌中有9例（21.4%）显示K-ras癌基因突变。42例结直肠癌中有6例（14.3%）显示p53基因热点点突变。本系列中p53基因突变频率较低可能是由于种族差异或不同的热点密码子。当检查6例p53基因突变的病例时，只有1例（16.7%）显示同时存在K-ras癌基因密码子12和p53基因密码子248突变。我们得出结论，在中国结直肠癌发生过程中，ras癌基因和p53基因热点点突变之间的协同作用并不常见。可能涉及其他因素，如腺瘤性息肉病大肠杆菌基因突变、癌基因激活或肿瘤抑制基因失活。
