婴幼儿血管瘤中p53基因突变及其蛋白表达

目的检测婴幼儿血管瘤中P53蛋白表达和p53基因第4～6外显子突变,以探讨p53基因在婴幼儿血管瘤发生发展中的作用机制。方法应用免疫组化S-P法检测了66例婴幼儿血管瘤组织中P53蛋白表达情况,用PCR-SSCP技术分析筛选并经测序,检测了25例婴幼儿血管瘤中p53基因外显子4～6的变化情况。结果 P53蛋白着色部位在肥大细胞胞浆内。增生期血管瘤中着色的肥大细胞数为31.18±9.08/HPF,高于消退期血管瘤14.05±6.42/HPF,两组之间差异显著(P0.01)。p53基因第4外显子PCR产物电泳条带异常者16例,经测序后发现14例为错义突变。第5、6外显子PCR产物中电泳条带异常者4例,经测序后发现1例第6外显子为同义突变。第5外显子未发现突变。结论 p53基因突变和蛋白误位可能参与了婴幼儿血管瘤的发生和发展过程。

The Protein Expression and Mutation of p53 Gene in Infantile Hemangioma

Objective To investigate P53 protein and p53 gene mutations in the tissues of infantile hemangioma.Methods The expression of p53 protein was detected by immunohistochemistry in 66 cases infantile hemangioma.The mutation in p53 gene exon 4 to 6 were identified by polymerase chain reaction based single-strand conformational polymorphism(PCR-SSCP)and subsequently conformed by DNA sequencing in 25 cases infantile hemangioma.Results The expression of P53 was located in the mast cells cytoplasm,The number of mast cells stained with p53 was 31.18±9.08/HPF in proliferative hemangiomas,Which higher than 14.05±6.42/HPF in involuting hemangiomas.There was significant differences between two groups(P<0.01).A missense mutation in exon 4 resulting in amino acid substitution was found in 14 pations(codon 72,CGC→CCC,Arginine→proline).A samesense mutation in exon 6 was found in 1 patient(codon 221,GAG→GAA,Glutamic Acid).Mutation in exon 5 was found in none of the studied cases.Conclution The mutation and protein expression of p53 gene participate in occurrence and developmnt of infant hemangioma.