小细胞肺癌患者和重度吸烟者体细胞染色体畸变的类型和断点

应用G显带方法,分析了17名重度吸烟者的小细胞肺癌(SCLC)患者骨髓和外周血细胞的180和172个核型;16名健康吸烟者和20名健康非吸烟者外周血淋巴细胞的367和336个核型。详细记载了畸变的类型和断点,不仅发现吸烟能引起很高的染色体结构和数目畸变,而且看到畸变的染色体片段和断点主要涉及1、2、3、9和11号染色体的某些区域,如1q,3p14—pter,11q13等。许多染色体断裂部位与目前已知的、并描绘在染色体模式图上的癌基因,染色体脆性部位和个体瘤细胞中发现的染色体重排的断点(癌断点)的位置重合或接近,本工作对3组人染色体畸变率和重排类型的分析,发现SCLC患者几乎都是对香烟烟雾作用敏感的个体。

The Types and Breakpoints of Somatic Chromosome Aberrations in Small Cell Lung Cancer (SCLC) Patients and Heavy Smokers

Detailed G-banded chromosome analyses were carried out on 180 bone marrow cells and 172 peripheral blood cells taken from 17 small cell lung cancer (SCLC) patients (Group A) and on 367 and 336 peripheral blood lymphocytes taken from 16 heavy smokers (Group B) and 20 healthy non-smokers (Group C).The results showed that Group A's structural aberration rate (32%) was higher than Group B's (22%) (P<0.01) and Group G's (2.6%) p<0.001).The difference between Group B and Group C was also significant (P< 0.001).The group A's numerical aberration rate (44%) was higher than that of group B's (18%) and Group C's (3.3%).All these implies that smoking is an important environmental factor causing human chromosome aberrations.The types and breakpoints of chromosome aberrations in every kary-otype analysed were described in detail.We not only discovered that smoking could cause very high rates of chromosomal structural and numerical aberrations but also noted that the breakpoints were mainly clustered in chromosomes 1,2,3,9 and 11,and were preferentially located in the regions 1q,3p14-pter,11q13,etc.Many breakpoints were near or at the map sites of the known fragile sites,oncogenes and/or cancer breakpoints.This pointed out that certain chromosomal breaks and rearrangements caused by smoking were nonrandom and could play an important role in making oncogenes and other relevant genes removed from their original sites and deregulated.Our results also showed that all SCLC patients examined had higher sensitivity to smoking.