胶质瘤中NGF、TrkA的表达及意义

Expressions and significance of NGF and TrkA in Human brain Astrocytoma

目的检测人脑胶质瘤组织内神经生长因子(nerve growth factor,NGF)及其与高亲和力受体酪氨酸蛋白激酶A(tyrosine kinase A,TrkA)的表达和意义。方法收集正常人脑组织标本10例及人脑胶质瘤标本34例,取胶质瘤标本按照2000年WHO脑胶质瘤分级标准分为I^IV级。其中Ⅰ级7例、Ⅱ级8例、Ⅲ级10例、Ⅳ级9例。用免疫组织化学方法检测NGF的蛋白表达情况。采用逆转录-聚合酶链反应(reverse transcription-polymerase chain reaction,RT-PCR)检测NGF的mRNA相对表达量。并采用Western blotting方法检测磷酸化TrkA(p-TrkA)的表达情况。结果 NGF在脑胶质瘤内蛋白和mRNA的表达高于正常脑组织,并且在脑胶质瘤内的表达与胶质瘤的病理级别相关,阳性表达率由高到低依次为Ⅲ级、Ⅱ级、Ⅳ级、Ⅰ级。p-TrkA在脑胶质瘤内表达量与NGF一致,与胶质瘤的病理级别有关。结论 NGF可能通过与其受体TrKA结合将信号转导到细胞内以促进胶质瘤的发生发展。

[Objectives] To detect the expression and significance of nerve growth factor （NGF）, and ty- rosine kinase A （TrkA） in tissues of human brain glioma. [Methods] 10 cases of normal human brain tissues and 34 cases of human glioma tissues were collected. The levels of glioma specimens were subdivided into I- IV, according to the criteria formulated by WHO in 2000 years. 7 cases were in I level, 8 cases were in 11 level, 10 cases were in m level, and 9 cases were in IV level. To examine the NGF protein＇s expression of the paraffin sections by the immunohistochemitry. To detect the relative quantity of NGF＇s mRNA expres- sion of the frigorific specimens, using the reverse transcription- polymerase chain reaction （RT-PCR）. Use Western blotting to detect the expression of phosphorylated TrkA （p-TrkA） protein. [Results] The protein and mRNA expression of NGF in the glioma was more than in the normal brain tissue, and the expression of NGF was associated with the glioma＇s pathological level. The positive expression rate＇ decreased gradually： grade Ⅲ, grade Ⅱ, grade IV and grade I. The expression of P-TrkA in human glioma was consistent with NGF and was relevant to the glioma＇s pathological grade. [Conclusions] NGF may through its receptor Trk A transduetion signal to cells for gliomas development and occurrence promotion.