头颈部鳞癌中p53-mdm2基因异常的研究

目的:检测头颈部鳞癌患者p53基因突变、mdm2基因扩增的状况,了解其与头颈部鳞癌患者的性别、鳞癌分级、淋巴结转移等的相关性及两异常基因的相关性。方法:收集50例行手术切除的头颈部鳞癌患者的新鲜肿瘤组织及其相应的癌旁正常组织,提取标本DNA;用PCR-SS-CP-银染法检测p53基因第5~8外显子的突变状况;用dPCR法检测mdm2基因扩增情况;采用SPSS 10.0统计软件包行2检验分析实验结果。结果:在50例头颈部鳞癌患者标本中,检测出17例存在p53基因突变,突变率为34%,所有的癌旁正常组织未发现p53基因突变;在50例鳞癌标本中检测出6例标本存在mdm2基因扩增,扩增率为12%,其中有一例同时存在p53基因突变;p53基因突变、mdm2基因扩增与患者的鳞癌分级、淋巴结转移、性别等相关性分析结果均无统计学意义(P>0.05)。结论:p53基因突变与mdm2基因扩增在头颈部鳞癌中较常见,可能是头颈部鳞癌发生发展的主要分子机制。

Study on the gene abnormalities of p53-mdm2 in head and neck squamous cell carcinoma

Aim: To investigate the mutation of gene p53, amplification of gene mdm2 in head and neck squamous cell carcinoma(HNSCC);statistically analyze the relationship between the two gene abnormalities,and to relate these gene abnormalities to the sex,tumor stage and lymph node metastasis.Methods: specimens of 50 cases of primary HNSCC and the normal tissue adjacent to tumor were collected.Genomic DNA was isolated from these tissues,gene p53 mutation was investigated at exon5~8 by polymerase chain reaction-single strand conformation polymorphism(PCR-SSCP);mdm2 gene amplification was analyzed by differential polymerase chain reaction(dPCR);all experimental data were statistically analyzed by using the software SPSS 10.0.Results: p53 gene mutation was detected in 17/50 cases(34%) of the HNSCC,while no mutation was detected in the normal epithelial tissues.mdm2 gene amplification was detected in 6/50 cases(12%).Of these 6 positive patients,one was found to have p53 gene mutation.The mutations of p53 and amplification of mdm2 were not significantly correlated to the sex,tumor stage and lymph node metastasis(P>0.05).Conclusion: Both p53 gene mutation and mdm2 gene amplification are frequently detected in HNSCC.These changes may be the key molecular mechanism in the tumor-genesis and development of HNSCC.