比较基因组杂交研究原发性胃癌的遗传学变异

目的研究原发性胃癌发生、发展过程中遗传学变异情况。方法采用比较基因组杂交分析23例原发性胃癌基因组DNA拷贝数变化情况。结果原发性胃癌患者平均每例肿瘤染色体臂变化数为7.52,扩增数要明显多于丢失数(5.38∶2.14)。DNA拷贝数扩增常见于8q(9/21,42.9%)、20q(9/21,42.9%)、17q(8/21,38.1%)、3q(7/21,33.3%)、7q(7/21,33.3%)、11q(6/21,28.6%)、13q(6/21,28.6%)、1q(5/21,23.8%)、20p(5/21,23.8%);DNA拷贝数缺失常见于17p(7/21,33.3%)、18q(6/21,28.6%)、5q(5/21,23.8%)、8p(5/21,23.8%)、9p(5/21,23.8%)。结论原发性胃癌中存在多条染色体拷贝数的变化,由此引起相应癌基因的扩增和抑癌基因的丢失可能参与了胃癌的发生和发展。

Chromosomal alterations analyzed by comparative genomic hybridization in primary gastric carcinoma

Objective To identify genetic abnormalities in primary gastric carcinoma.Methods Comparative genomic hybridization(CGH)was used in screening DNA copy number changes along all chromosomes in 23 cases of primary gastric cancer.Results Twenty-one out of 23 cases showed chromosomal losses and gains for at least one of the chromosomal arms in primary gastric cancer.The mean number of chromosomal alterations was 7.52.Chromosomal gains predominated over chromosomal losses in a ratio of 5.38:2.14.The most often involved chromosomal gains were observed in 8q(9/21,42.9%),20q(9/21,42.9%),17q(8/21,38.1%),3q(7/21,33.3%),7q(7/21,33.3%),11q(6/21,28.6%),13q(6/21,28.6%),1q(5/21,23.8%)and 20p(5/21,23.8%).The chromosomal arms with frequent losses were 17p(7/21,33.3%),18q(6/21,28.6%),5q(5/21,23.8%),8p(5/21,23.8%),and 9p(5/21,23.8%).Conclusions The phenomenon of gain and loss of chromosomal regions is observed in primary gastric cancer,which may induce the amplification of oncogenes and the loss of tumor suppressor genes to regulate the development and progression of gastric cancer.