肺癌患者吸烟量与痰液细胞p53和Ki—ras基因突变的关系

目的　了解痰液细胞癌基因突变是否与肺癌患者的吸烟量有相关性。方法　将痰液 0 .5毫升加入痰处理液制备细胞沉淀液 ,酚氯仿提取DNA ;应用SSCP PCR银染和RFLP PCR方法对痰液中p5 3、K ras突变情况进行检测。统计肺癌患者的香烟消耗量 ,分析p5 3、K ras突变与吸烟量的关系。结果　在确诊的 110例肺癌中 ,存在p5 3或K ras基因突变者有 76例 ,突变率达 69.1% ,其中 16例为p5 3和K ras基因均有突变。全组中有 71例重度吸烟者吸烟指数 (≥ 40 0支·年 ) ,71例中 5 5例有p5 3或K ras基因突变 ,突变率达 77.5 % ,显著高于非吸烟组 (P <0 .0 0 1) ;p5 3和K ras突变患者的平均吸烟指数分别达到 861和 63 0支·年 ;而未突变的平均吸烟指数为 2 84和 5 5 4支·年 ,二者之间有显著性差异 ( χ2 =3 6.5 6,P =0 .0 0 2 ,双尾检验 )。结论　痰液细胞癌基因突变检测具有简便、实用、可行的特点 ,吸烟的肺癌患者中癌基因突变率显著高于非吸烟的肺癌患者 ,提示吸烟尤其是重度吸烟可能是支气管癌基因突变的主要原因之一 ,值得临床进一步开展深入的研究。

The relationship between smoking and p53 and Ki-ras gene mutations in sputum cells of patients with lung cancer

Objective　To study the relationship between gene's mutation in sputum cells and smoking consumption of patients with lung cancer. Methods　Sputum dispose liquid was added into 0.5?ml sputum, DNA was extracted twicely with saturated phenol-chloroform and ethanol precipitate; p53 and K-ras gene mutations were detected by using SSCP-PCR and RFLP-PCR methods. Results　Seventy-one of 110 patients with lung cancer were heavy smokers (index of smoking≥400), 55 of 71(77.5％) patients with heavy smoking were detected with gene alterations of p53 or K-ras (P＜0.05). Average indexes of smoking in the patients with p53 or K-ras were 861 and 630 respectively, whereas those in non-smokers were 284 and 554 (χ2＝36.56,P＝0.002). Conclusion　Detection of oncogene alterations in sputum is a simple method to practice. Oncogene alteration in smoking patients with lung cancer is higher, especially in heavy smokers, than those with no smoking. The results show that heavy smoking is one of the causes in oncogene mutations of bronchus and further investigation is necessary.