Department of Surgery, The First Affiliated Hospital Guangxi Medical University Nanning 530021, China.
Exp Mol Med. 2011 Nov 30;43(11):638-45. doi: 10.3858/emm.2011.43.11.072.
The E2F-1 transcription factor is post-translationally modified and stabilized in response to various forms of DNA damage to regulate the expression of cell-cycle and pro-apoptotic genes. The sustained overexpression of E2F-1 is a characteristic feature of gastric cancer. In this study, we investigated the role of short hairpin RNA (shRNA) targeting E2F-1 gene on human gastric cancer MGC-803 cell growth in vivo, and preliminarily revealed the mechanism. Thus, we constructed recombinant pGCSIL-GFP-shRNA-E2F-1 lentiviral vector to knock down E2F-1 expression in human gastric cancer MGC-803 cells in vivo, and studied the effect of E2F-1 shRNA on growth of MGC-803 tumor and evaluated its treatment efficacy. Our data demonstrated that in a mouse model of established gastric cancer, intratumor injection of lentiviral shRNA targeting E2F-1 definitely decreased the endogenous E2F-1 mRNA and protein expression in MGC-803 tumor, and inhibited tumor growth and promoted tumor cells apoptosis. Moreover, we found that E2F-1 shRNA increased the expression of phosphatase and tensin homolog (PTEN), activated caspase-3 and caspase-9, and suppressed nuclear factor (NF)-κB expression in tumor tissue as determined by reverse transcription (RT)-PCR and western blotting. In summary, shRNA targeting of E2F-1 can effectively inhibits human gastric cancer MGC-803 cell growth in vivo and may be a potential therapeutic strategy for gastric cancer.
E2F-1 转录因子在受到各种形式的 DNA 损伤后发生翻译后修饰并稳定，从而调节细胞周期和促凋亡基因的表达。E2F-1 的持续过表达是胃癌的一个特征。在本研究中，我们研究了针对 E2F-1 基因的短发夹 RNA（shRNA）在体内对人胃癌 MGC-803 细胞生长的作用，并初步揭示了其机制。因此，我们构建了靶向 E2F-1 基因的重组 pGCSIL-GFP-shRNA-E2F-1 慢病毒载体，以在体内敲低人胃癌 MGC-803 细胞中的 E2F-1 表达，并研究了 E2F-1 shRNA 对 MGC-803 肿瘤生长的影响及其治疗效果。我们的数据表明，在建立的胃癌小鼠模型中，肿瘤内注射靶向 E2F-1 的慢病毒 shRNA 可明显降低 MGC-803 肿瘤中的内源性 E2F-1 mRNA 和蛋白表达，抑制肿瘤生长并促进肿瘤细胞凋亡。此外，我们通过逆转录（RT）-PCR 和 Western blot 发现，E2F-1 shRNA 增加了肿瘤组织中磷酸酶和张力蛋白同源物（PTEN）、激活的 caspase-3 和 caspase-9 的表达，并抑制了核因子（NF）-κB 的表达。综上所述，靶向 E2F-1 的 shRNA 可有效抑制体内人胃癌 MGC-803 细胞的生长，可能是胃癌的一种潜在治疗策略。
