EGF作用下人脑胶质瘤细胞生长抑制的机理

Isolation and Cloning of Genes Related to Growth Inhibition of Human Glioma BT325 by EGF

目的 克隆、测序胶质细胞瘤 BT325细胞在生长抑制量表皮生长因子 (epithelial growth factor EGF)作用下差异表达的基因,了解 BT325细胞生长抑制的分子机制。方法 在生长抑制量 EGF 作用下,用差异显示反转录聚合酶链反应 (differential display reversed transcription polym erase chain reaction DDRT-PCR ) 技 术 分析 人 胶 质 细胞瘤 BT325细胞表达 水 平 明显 差 异 的 cDNA , 对差 异 显 示 基因 进 行 序 列 测定 和 同 源 比较 , 并 用 Dot blot及 Northernblot等方法进行验证。结果 在 EGF 作用下,生长抑制的胶质瘤细胞中出现一些上调和下调表达的 cDNA 片段。克隆、分离了 6个表达明显上调的 ESTs,1个序列为新的基因片段,另 5个与已知基因有不同程度的同源,其中 1个与转醛缩酶基因的编码区同源。新近的研究已发现,转醛缩酶与细胞凋亡有关。结论 高剂量 EGF 可诱导 BT325中许多基因表达水平的改变,EGF 抑制 BT325细胞生长可能与促进转醛缩酶基因的表达而诱导细胞凋亡有关。

Objective To isolate and clone the differentially expressed genes induced by epithelial growth factor(EGF)with inhibiting dosage in cultured glioma BT325 cells and understand the molecular mechanism that inhibits glioma cells growth. Methods Using differential display reversed transcription polymerase chain reaction(DDRT-PCR)method to analyze the differentially expressed cDNA in BT325 cells induced by EGF with inhibiting dosage. After sequencing and homology research, the differentially expressed cDNA fragments were further confirmed by Dot blot analysis and one of them by Northern blot. Results Up-regulated genes cDNA fragments were isolated in growth inhibited BT325 cells. It was found that five cDNA fragments were highly homologous to the known human genes, while one was a fragment of a novel genes. Among these genes, one has coding sequence homology with transaldolase(TAL), which has been proved to be associated with apoptosis in recently research. Conclusions High-dose EGF could change the expression of many genes in BT325 cells. EGF can inhibit the growth of BT325 cell growth, which may be resulted from its potential role in promoting TAL gene expression and thus inducing cell apoptosis.