荧光原位杂交检测非小细胞肺癌EGFR基因拷贝数状况分析

Analysis of epidermal growth factor receptor gene copy status in non-small cell lung cancer by fluorescence in situ hybridization

目的探讨非小细胞肺癌EGFR基因拷贝数状况的临床病理学意义。方法采用LSIEGFR/CEP7探针试剂盒对108例非小细胞肺癌石蜡包埋组织标本进行EGFR基因状况的检测,并分析EGFR基因拷贝数与患者临床病理学之间的关系。结果在108例非小细胞肺癌病例中,64.8%病例判读为EGFR基因低基因拷贝数即FISH阴性,其中二体性21.3%、低度三体性18.5%、高度三体性13.9%、低度多体性11.1%。35.2%病例判读为EGFR基因高基因拷贝数即FISH阳性,其中高度多体性25.9%、基因扩增9.3%。除2例扩增病例(Ratio>2.4)外,所有三体性及多体性,7号染色体与EGFR基因的拷贝数出现一致性的增加,Ratio范围在1.12～1.54之间。EGFR基因状况或EGFR-FISH(-/+)与临床病理特征均无显著相关性。结论 EGFR基因拷贝数增加在非小细胞肺癌是较常发生的事件,可能参与肺癌的发生发展。

Objective To investigate the clinicopathological significance of epidermal growth factor receptor（EGFR） gene copy number in non-small cell lung cancer.Methods Using LSI EGFR/CEP 7 probe,EGFR gene copy number was evaluated by fluorescence in situ hybridization（FISH） in formalin-fixed paraffin-embedded samples from 108 non-small cell lung cancer（NSCLC）,and the relationship between EGFR gene status and clinical features was analyzed.Results A low gene copy（EGFR FISH-negative） was found in 64.8% of the case（disomy in 21.3%,low trisomy 18.5%,high trisomy 13.9% and low polysomy 11.1%）.A high EGFR gene copy（EGFR FISH-positive） was found in 35.2% of the case（high polysomy in 25.9% and amplification in 9.3%）.Expect EGFR gene amplification with a ratio of greater than 2.4 in 2 cases,nearly all of the trisomy and polysomy cases exhibited concordant gains in the copy numbers for both the EGFR gene and chromosome 7（Ratio = 1.12～1.54）.There was no significant difference in EGFR FISH status or EGFR gene amplification with respect to sex,histology,tumor differentiation,lymphatic metastasis and clinical grade.Conclusion EGFR gene copy number increase is much more frequent in NSCLC,and may involved in the tumorigenesis and development of NSCLC.