Ito Tomohiro, Kaneko Kazuhiro, Makino Reiko, Konishi Kazuo, Kurahashi Toshinori, Ito Hiroaki, Katagiri Atsushi, Kushima Miki, Kusano Mitsuo, Mitamura Keiji, Imawari Michio
Second Department of Internal Medicine, Showa University School of Medicine, Tokyo 142-8666, Japan.
Oncol Rep. 2003 Nov-Dec;10(6):1937-42.
Circulating DNA can be isolated from serum of patients with various carcinomas and p53 mutation can be observed in colorectal carcinoma. The aim of this study was to investigate the correlation between p53 mutation in DNA extracted from colorectal carcinoma and that in DNA extracted from serum of patients with colorectal carcinoma. The clinical significance in molecular detection of p53 mutation in serum of patients with colorectal carcinomas was also investigated. DNA was extracted from tumors and non-tumorous colorectal tissues of 46 patients with single sporadic colorectal carcinomas of stage I (n=6), stage II (n=18), stage III (n=15), and stage IV (n=7) according to the TNM classification. Circulating DNA was also extracted from the serum of the 46 patients with colorectal carcinoma and from 7 healthy volunteers for normal control. Mutations of the p53 gene were analyzed using a fluorescence-based polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) method. DNA sequences were determined in DNA fragments with shifted peaks by SSCP methods. Mutations in tumors were found in 22 (48%) of 46 patients, and mutations in serum were found in 3 (14%) of these 22 patients. Of 4 patients with stage IV disease, 3 (75%) had serum p53 mutation and the mutation pattern of these 3 patients was the same in both tumor and serum. No correlation was seen between p53 mutation in serum and the level of serum DNA. There was no significant difference between the presence of p53 mutation in serum and tumor size, depth of invasion, vascular invasion, or lymph node metastasis. However, liver metastasis showed significant difference (p=0.0026). The presence of p53 mutation in serum was associated with a clinically advanced stage accompanied by liver metastasis.
可从各种癌症患者的血清中分离出循环DNA，且在结直肠癌中可观察到p53突变。本研究旨在探讨从结直肠癌中提取的DNA与从结直肠癌患者血清中提取的DNA中p53突变之间的相关性。还研究了结直肠癌患者血清中p53突变分子检测的临床意义。根据TNM分类，从46例单发散发性结直肠癌患者的肿瘤及非肿瘤性结直肠组织中提取DNA，这些患者的分期为I期（n = 6）、II期（n = 18）、III期（n = 15）和IV期（n = 7）。还从这46例结直肠癌患者的血清以及7名健康志愿者的血清中提取循环DNA作为正常对照。采用基于荧光的聚合酶链反应（PCR）-单链构象多态性（SSCP）方法分析p53基因的突变情况。通过SSCP方法对出现峰位移的DNA片段进行DNA序列测定。46例患者中有22例（48%）肿瘤中发现突变，这22例患者中有3例（14%）血清中发现突变。在4例IV期疾病患者中，3例（75%）血清中有p53突变，这3例患者的肿瘤和血清中的突变模式相同。血清中p53突变与血清DNA水平之间无相关性。血清中p53突变的存在与肿瘤大小、浸润深度、血管浸润或淋巴结转移之间无显著差异。然而，肝转移显示出显著差异（p = 0.0026）。血清中p53突变的存在与伴有肝转移的临床晚期相关。
