Zhao Zhan-kao, Jiang Zhong-min, Liu Xiao-zhi, Chen Yan-ting, Jia Wen-juan
Department of Pathology, the Affiliated Hospital of the Medical College of Chinese People's Armed Police Force, Tianjin 300162, China.
Zhonghua Bing Li Xue Za Zhi. 2010 Jun;39(6):400-4.
To study the therapeutic efficacy of siRNA fragments silencing p75 neurotrophin receptor (p75(NTR)), which may be a key regulator of glioma cell apoptosis and invasion.
The siRNA sequence fragments targeting p75(NTR) were designed and transferred into human glioma cell line U251. RT-PCR and immunocytochemistry method were used to explore the expression of p75(NTR) mRNA and protein. Cell adhesion assay was employed to detect cellular adhesion ability, and soft agar clone formation assay was adopted to identify oncogenicity, and a U251 glioma model was established in nude mice. The intracranial tumor volume was detected by MRI. The expression of p75(NTR), NGF and cyclin D2 were identified using immunohistochemistry. Cell apoptosis was detected by apoptosis kit in situ.
The siRNA fragments targeting p75(NTR) were capable of decreasing mRNA and protein expression of p75(NTR) in U251 glioma cell line. Both the cellular adhesion ability and oncogenicity were weakly relevant. The p75(NTR) expression level was negatively correlated with cyclin D2 and apoptosis, and positively correlated with NGF expression. The siRNA sequence fragments targeting p75(NTR) were effective in decreasing the gross volume of tumor; prolonged the survival time of mice, and the edge of tumor was much sharper than that of the control group.
The gene silencing technique by siRNA targeting p75(NTR) is capable of decreasing tumor invasion and cell proliferation as well as inducing cell apoptosis. It is expected to be a new choice for glioma gene therapy.
研究沉默p75神经营养因子受体（p75(NTR)）的小干扰RNA（siRNA）片段的治疗效果，p75(NTR)可能是胶质瘤细胞凋亡和侵袭的关键调节因子。
设计靶向p75(NTR)的siRNA序列片段并将其转入人胶质瘤细胞系U251。采用逆转录-聚合酶链反应（RT-PCR）和免疫细胞化学方法检测p75(NTR) mRNA和蛋白的表达。采用细胞黏附试验检测细胞黏附能力，采用软琼脂克隆形成试验鉴定致瘤性，并在裸鼠中建立U251胶质瘤模型。通过磁共振成像（MRI）检测颅内肿瘤体积。采用免疫组织化学法鉴定p75(NTR)、神经生长因子（NGF）和细胞周期蛋白D2的表达。采用原位凋亡试剂盒检测细胞凋亡。
靶向p75(NTR)的siRNA片段能够降低U251胶质瘤细胞系中p75(NTR)的mRNA和蛋白表达。细胞黏附能力和致瘤性均呈弱相关性。p75(NTR)表达水平与细胞周期蛋白D2和凋亡呈负相关，与NGF表达呈正相关。靶向p75(NTR)的siRNA序列片段可有效减小肿瘤总体积；延长小鼠生存时间，且肿瘤边缘比对照组更清晰。
靶向p75(NTR) 的siRNA基因沉默技术能够降低肿瘤侵袭和细胞增殖并诱导细胞凋亡。有望成为胶质瘤基因治疗的新选择。
