Lu Weizhong, Huang Guijun, Qian Guisheng, Li Yuying, Yu Shicang, Li Jin
Institute of Respiratory Diseases, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, P.R.China.
Zhongguo Fei Ai Za Zhi. 2005 Apr 20;8(2):95-8. doi: 10.3779/j.issn.1009-3419.2005.02.04.
Angiogenesis is essential for tumor's growth and metastasis. Canstatin, a newly found potent endogenous angiogenesis inhibitor, has drawn researcher's attention to its powerful biological activities on endothelial cells. The aim of this experiment is to explore the expression and effects of canstatin gene in lung cancer A549 cells and HUV-ECC cells.
Expression vector of pCMV- Script/Canstatin was transfected into A549 and ECC cells by electroporation, and the positive clone was screened by G418. Growth characteristics of the two cell lines were compared before and after transfection. Expression of canstatin protein in supernatant was examined by SDS-PAGE assay, and cell cycles of the two cell lines were analysed by flow cytometry.
The expression of canstatin gene was found in supernatant of the transfected A549 cells and ECC cells. The apoptotic rate in the transfected ECC cells (16.04%) was significantly increased compared with that of the naked plasmid control group (0.43%) and parental cell group (2.92%) (P < 0.01). The growth of the transfected ECC cells was significantly inhibited (P < 0.01). The apoptotic rate in the transfected A549 cells (0.19%) showed no marked difference from the naked plasmid control group (0.13%) and parental cell group (0.07%) (P > 0.05). No significant difference in cell growth was found among the transfected A549 cell, naked plasmid control and parental cell groups.
The results indicate that canstatin gene can express in lung cancer A549 cell line and HUV-ECC cell line, and it can specifically inhibit proliferation of endothelial cell and induce its apoptosis.
血管生成对于肿瘤的生长和转移至关重要。Canstatin是一种新发现的强效内源性血管生成抑制剂,其对内皮细胞的强大生物学活性已引起研究人员的关注。本实验旨在探讨Canstatin基因在肺癌A549细胞和人脐静脉内皮细胞(HUV-ECC)中的表达及作用。
通过电穿孔将pCMV-Script/Canstatin表达载体转染至A549细胞和人脐静脉内皮细胞中,并用G418筛选阳性克隆。比较转染前后两种细胞系的生长特性。采用SDS-PAGE法检测上清液中Canstatin蛋白的表达,并用流式细胞术分析两种细胞系的细胞周期。
在转染后的A549细胞和人脐静脉内皮细胞的上清液中发现了Canstatin基因的表达。与空质粒对照组(0.43%)和亲本细胞组(2.92%)相比,转染后人脐静脉内皮细胞的凋亡率(16.04%)显著升高(P<0.01)。转染后人脐静脉内皮细胞的生长受到显著抑制(P<0.01)。转染后A549细胞的凋亡率(0.19%)与空质粒对照组(0.13%)和亲本细胞组(0.07%)相比无明显差异(P>0.05)。转染后的A549细胞、空质粒对照组和亲本细胞组之间的细胞生长无显著差异。
结果表明,Canstatin基因可在肺癌A549细胞系和人脐静脉内皮细胞系中表达,且能特异性抑制内皮细胞增殖并诱导其凋亡。