贲门癌中染色体8p21-p23杂合性丢失的研究

目的 研究贲门癌中染色体8p21-p23杂合性丢失的情况。方法 采用激光捕获显微切割技术获得均质的肿瘤细胞及正常的胃粘膜细胞，多重置换扩增技术扩增捕获细胞的基因组DNA。PCR结合硝酸银染色方法分析19例贲门癌染色体8p21-p23的杂合性丢失。结果 在贲门癌中染色体8p21-p23的缺失频率非常高（63.2%），我们确定了一个最小丢失区域. 结论 进一步明确此最小丢失区域内的抑癌基因将有助于贲门癌发生机制的阐明。

Loss of heterozygosity at chromosome 8p21-p23 in adenocarcinoma of gastric cardia

Chromosome 8p21-p23 harbors tumor suppressor gene(s) implicated in multiple types of cancers.To investigate the involvement of the gene(s) in the carcinogenesis of adenocarcinoma of gastric cardia,loss of heterozygosity(LOH) for microsatellite markers at chromosome 8p21-p23 was examined.Laser capture microdissection(LCM) was used to obtain homogeneous tumor cells from 19 surgical specimens. Subsequently,genomic DNA extracted from the LCM-captured cells was amplified by multiple displacement amplification.Each tumor was assessed for allelic loss using 13 microsatellite markers.An overall LOH frequency of 63.2%(12/19) was observed and the LOH frequency for individual markers varied from 25% to 55.6%.One common deleted region of about 1.2 Mb(8p22GGAA-8p22ATCT) was defined.Our data indicated that the tumor suppressor gene at chromosome 8p22 might play an important role in the development of adenocarcinoma of gastric cardia.