100例脑肿瘤中p53基因突变与P53蛋白积聚的研究

目的:研究不同类型脑肿瘤中的p53基因突变与P53蛋白积聚及其相关性。方法:采用聚合酶链反应-单链构象多态性(PCR-SSCP)分析及免疫组化法检测100例脑肿瘤p53基因突变及蛋白表达。结果:p53基因突变率为11%(11/100),其中高恶度胶质瘤为37.5%(6/16),低恶度胶质瘤4.3%(1/23),脑膜瘤6.9%(2/29),转移瘤40.0%(2/5)。P53蛋白表达阳性率为22%(22/100),其中高恶度胶质瘤为62.5%(10/16),低恶度胶质瘤为26.1%(6/23),脑膜瘤10.3%(3/29),转移瘤60%(3/5);其他肿瘤均未发现p53基因突变或蛋白表达。P53蛋白表达阳性的22例中伴有p53基因突变者11例,多见于高恶度肿瘤。结论:p53基因失活在脑肿瘤恶性进展过程中起重要作用。p53基因突变与P53蛋白积聚相关,但并非唯一因素。

Study of p53 Gene Mutation and P53 Protein Accumulation in 100 Cases of Brain Tumors

Aim: To study the frequency of p53 gene mutation and protein accumulation in different types of brain tumors. Methods: 100 cases of brain tumors were detected with PCR-SSCP and immunohistochemical methods. Results:p53 gene mutation was found in 11 out of 100 cases of brain tumors(11%). The frequency of mutation was 37. 5%(6/16) in high grade gliomas, 4. 3%(l/23) in low grade gliomas, 6. 9 (2/29) in meningiomas and 40%(2/5)in metastatic tumors. Total positive rate of p53 protein expression was 22%(6/ 23) in low grade gliomas, 10. 3%(3/29) in meningiomas and 60%(3/5) in metastatic tumors. No p53 gene mutation and protein expression were found in other types of brain tumors. 11 cases with both p53 gene mutation and protein expression were malignant tumors. Conclusion: p53 gene inactivation plays an important role in the malignant progression of brain tumors. p53 gene mutation was correlated with the accumulation of p53 protein, but it was not the only factor which causes the accumulation of p53 protein.