儿童神经母细胞瘤中ALK基因突变的研究

ALK gene mutations in childhood neuroblastoma

目的探讨中国儿童神经母细胞瘤(NB)中间变性淋巴瘤激酶(ALK)基因的突变情况。方法从22例石蜡包埋的NB肿瘤组织中提取基因组DNA,通过PCR-DNA直接测序技术分析儿童NB肿瘤组织中ALK突变热点区域第20～26号外显子的突变情况。结果 22例儿童NB中,有10例(46%)在ALK第21号外显子上存在已知同义突变C3375A(Gly1125Gly),等位基因频率为27%;1例(5%)在ALK第23号外显子上发现一个新的同义突变C3586T(Leu1196Leu)。ALK突变C3375A的发生频率在NB患儿的年龄、性别、肿瘤分化程度和是否转移方面差异无统计学意义(P>0.05)。在其他5个ALK外显子中未发现突变。结论采用PCR-DNA测序技术发现了ALK一个新的同义突变C3586T,并证实了儿童ALK存在已知突变C3375A,其发生率不受NB患儿临床特征的影响。

Objective To investigate mutations of anaplastic lymphoma kinase（ALK） in Chinese children with neuroblastoma（NB）.Methods Genomic DNA was extracted from 22 cases of paraffin-embedding NB tumor tissues.Gene mutations in the exons 20-26 which were mutational hotspots of ALK were analyzed by PCR-DNA direct sequencing.Results A novel synonymous mutation C3586T（Leu1196Leu） and a known synonymous mutation C3375A（Gly1125Gly） were found and located at exon 23 and exon 21 of ALK respectively.There were 10 cases（46%） of known synonymous mutation C3375A in 22 cases of NB.The C3375A allelic frequency was 27%.No statistically significant correlation was found between mutation C3375A and clinical parameters of NB such as age,sex,metastasis and tumor differentiation.Mutation was not found in the other 5 exons.Conclusions A novel ALK gene synonymous mutation C3586T was identified using PCR-DNA sequencing.A known mutation C3375A in ALK was successfully identified in children,and its incidence is not influenced by the clinical features of childhood NB.