Liu Ming-yue, Hou Gui-qin, Zhang Yan, Bei Wei-juan, Yan Ai-hua
Department of Oncology, People's Hospital of Henan Province, Zhengzhou 450003, China.
Zhonghua Zhong Liu Za Zhi. 2011 May;33(5):334-9.
To investigate the effects of mTOR siRNA on mTOR-p70S6K signaling pathway in esophageal squamous cell carcinoma (ESCC) cells in vitro,and growth and apoptosis in transplanted tumor in nude mice.
mTOR siRNA was transfected into ESCC cell line EC9706 cells. The expressions of factors of the mTOR/p70S6K signaling pathway were detected by RT-PCR and Western blot. DNA contents and cell apoptosis were determined by flow cytometry, and cell proliferation was measured by CCK-8 assay. The effects of mTOR siRNA on the transplanted tumor growth were assessed in nude mice.
The levels of mTOR and p-p70S6K were significantly decreased (P < 0.05) while the level of p70S6K was increased (P < 0.05) in the cells transfected with mTOR siRNA, compared with that in untransfected cells and cells transfected with control siRNA. After being interfered by mTOR siRNA, the number of apoptotic cells was increased, cell proliferation became slower and cell cycle was arrested in G(1) phase compared with that in control cells. Also, mTOR siRNA inhibited the growth of transplanted tumor in vivo.
mTOR siRNA can effectively interfere in mTOR-p70S6K signaling pathway, induce cell apoptosis and inhibit cell proliferation and tumor growth, suggesting that mTOR-p70S6K signaling pathway plays an important role in the carcinogenesis and development of esophageal squamous cell carcinoma.
探讨mTOR小干扰RNA（siRNA）对食管鳞状细胞癌（ESCC）细胞体外mTOR-p70S6K信号通路及裸鼠移植瘤生长和凋亡的影响。
将mTOR siRNA转染至ESCC细胞系EC9706细胞。采用逆转录-聚合酶链反应（RT-PCR）和蛋白质免疫印迹法检测mTOR/p70S6K信号通路相关因子的表达。通过流式细胞术检测DNA含量及细胞凋亡情况，采用细胞计数试剂盒-8（CCK-8）法检测细胞增殖。评估mTOR siRNA对裸鼠移植瘤生长的影响。
与未转染细胞及转染对照siRNA的细胞相比，转染mTOR siRNA的细胞中mTOR和磷酸化p70S6K（p-p70S6K）水平显著降低（P<0.05），而p70S6K水平升高（P<0.05）。mTOR siRNA干扰后，与对照细胞相比，凋亡细胞数量增加，细胞增殖减慢，细胞周期阻滞于G(1)期。此外，mTOR siRNA抑制裸鼠体内移植瘤的生长。
mTOR siRNA可有效干扰mTOR-p70S6K信号通路，诱导细胞凋亡，抑制细胞增殖和肿瘤生长，提示mTOR-p70S6K信号通路在食管鳞状细胞癌的发生发展中起重要作用。
