p53基因突变与喉癌生物学行为的关系

The relationship of p53 gene mutation to cell differentiation and metastasis of laryngeal squamous cell carcinoma

目的 探讨 p5 3基因突变与喉癌生物学行为的关系。方法 应用聚合酶链反应 -单链构象多态性 (PCR- single strand conformation polymorphism,PCR- SSCP)银染技术结合 DNA直接测序 ,检测喉鳞癌新鲜或冰冻组织中 p5 3外显子 5～ 8的基因突变。结果 - 、 - 喉鳞癌 p5 3基因突变率分别为6 9. 2 % (18/2 6 )和 85 .3% (2 9/34 ) ,P>0 .0 5 ;高、中、低分化程度的突变率依次为 5 2 .9% (9/17)、83.3%(2 0 /2 4)和 94.7% (18/19) ,P<0 .0 5 ;有、无颈淋巴结转移者突变率分别为 96 .4% (2 7/2 8)和 6 2 .5 % (2 0 /32 ) ,P<0 .0 1。从 47例 SSCP阳性标本中随机抽取 2 0例进行测序 ,19例测序为阳性 ,二者符合率为 95 %。结论 p5 3基因突变与病理分化程度及颈淋巴结转移有明显相关性。

Objective To inquire about the relationship of p53 gene mutation to the histopathological findings and clinical manifestation in cases of laryngeal squamous cell carcinoma (LSCC). Methods The fresh samples from 60 cases of LSCC were examined. Polymerase chain reaction and silver staining-single strand conformation polymorphism (PCR-SSCP) and DNA direct sequencing were used to detect the mutation of p53 gene in exons 5-8. Results The mutation rates were 69.2% and 85.3% in patients at clinical stage Ⅰ-Ⅱ and stage Ⅲ-Ⅳ respectively ( P >0.05). In the well-, moderately- and poorly-differentiated cell of LSCC, the mutation rates were 52.9%, 83.3% and 94.7% respectively ( P <0.05). The p53 gene mutation rate of LSCC patients with neck lymph-node metastasis was 96.4%, whereas that of patients without neck lymph-node metastasis was 62.5% ( P <0.05). Twenty samples showed positive results in SSCP; 19 samples showed deletion and mutation in codons 125-292 by DNA direct sequencing. Conclusion The mutation of p53 gene in exons 5-8 was closely related to cell differentiation and the neck lymph-node metastasis of LSCC, but it was not related to the clinical stages of the LSCC cases.