胰腺癌患者血浆K-ras和p53基因突变检测的研究

Detection of K-ras and p53 gene mutations in the plasma of patients with pancreatic carcinoma

目的 检测胰腺癌患者血浆K ras和p5 3基因突变情况 ,初步分析其诊断价值。方法 本研究包括胰腺癌组 2 4例、其他疾病组 14例和健康对照组 2 1例。提取血浆DNA ,采用突变富集PCR RFLP法检测K ras基因第 12密码子突变 ,PCR SSCP 银染法检测p5 3基因第 5～ 8外显子突变。结果 2 4例胰腺癌患者中 17例血浆检测到K ras突变 ,3例检测到p5 3突变 ;2 1例健康对照者血浆中均未检测到K ras和p5 3突变 ;在 38例疑为胰腺肿瘤患者中 ,血浆K ras突变诊断胰腺癌的敏感性为 70 % ,特异性为 86 % ,阳性预测值为 90 % ,阴性预测值为 6 3%。结论 本研究提示通过胰腺癌患者血浆标本检测K ras和p5 3基因突变是可行的。血浆K ras突变分析有助于胰腺癌的诊断。

Objective To study the detection of K-ras and p53 gene mutations in the plasma of patients with pancreatic carcinoma. Methods Twenty-four patients with pancreatic carcinoma, 14 patients with other diseases in pancreatic area and 21 healthy controls were included in the present study. DNA from plasma was extracted. Point mutation at codon 12 of K-ras gene was analyzed using mutation enriched-polymerase chain reaction-restriction fragment length polymorphism technique. Mutation of exons 5～8 of p53 gene was detected using polymerase chain reaction-single strained conformation polymorphism-silver staining technique. Results K-ras and p53 gene mutations were detected in the plasma of 17 of 24 and 3 of 24 patients with pancreatic carcinoma, respectively, but were not detected in any of the healthy controls. In 38 patients with suspected pancreatic masses, the sensitivity and specificity of plasma K-ras analysis for pancreatic carcinoma were 70% and 86%, respectively. The positive predictive value and negative predictive value for plasma K-ras mutation analysis were 90% and 63%, respectively. Conclusion The results indicate that it is possible to detect K-ras and p53 gene mutatons in DNA extracted from the plasma of patients with pancreatic carcinoma. Plasma K-ras analysis may be useful in the diagnosis of pancreatic carcinoma.