annexin Ⅰ基因在胰腺癌中的表达及其对胰腺癌细胞生物学行为的影响

目的探讨annexinⅠ基因在胰腺癌发生过程中的作用。方法通过免疫组化方法确认annexinⅠ基因在胰腺癌组织中的高表达,合成annexinⅠ基因的小分子RNA干扰片断(siRNA)及无关序列,并构建RNA干扰片断的重组真核表达载体,将重组真核载体稳定转染胰腺癌细胞。通过RNA干扰(RNAi)的方法,敲低annexinⅠ基因在mRNA水平的表达。通过逆转录聚合酶链反应(RT- PCR)、免疫细胞化学、流式细胞技术和二苯基溴化四氮唑蓝(MTT)法,证实annexinⅠ基因的表达被敲低后,对胰腺癌细胞的生长速度、细胞形态、细胞周期、凋亡情况进行观察和检测。结果敲低annexinⅠ基因的表达后,胰腺癌细胞形态发生了显著的变化,呈多形性、空泡样变性以及脂滴形成等,G1期明显延长,出现了明显的凋亡,凋亡率分别为29.8%和18.8%,胰腺癌细胞的恶性表型被抑制。结论annexinⅠ基因在胰腺癌的发生过程中起到了调控肿瘤细胞周期、促进肿瘤细胞生长增殖和抑制凋亡的重要作用。

Expression of annexin I in human pancreatic cancer and the influence of its down-regulation on biology of this cancer

OBJECTIVE: To investigate the expression of annexin in human pancreatic cancer and to elucidate its role in oncogenesis of pancreatic cancer. METHODS: A pancreatic carcinoma cell line Suit-II with high-expression of annexin I gene was adopted. Three subtypes of annexin I -siRNA sequences and a non-related fragment were combined, and the eukaryotic expression vectors bearing siRNA fragments were constructed. Then they were transfected into pancreatic carcinoma cells to knock down the expression of annexin I by RNAi. After knocking down the expression of annexin I , the growth speed, cell cycling, morphological features and apoptosis of pancreatic carcinoma cells were examined by RT-PCR and MTT test. RESULTS: When the expression of annexin I was blocked, the growth speed of pancreatic carcinoma cells was significantly decreased, the morphological features were changed and pronounced apoptosis occurred. CONCLUSION: Annexin I can modulate pancreatic carcinoma cell cycle, promote the cell proliferation, increasingly stimulate the cell growth, and suppress the process of apoptosis in pancreatic carcinoma cells.