血管生成素样蛋白2在结肠直肠癌的表达及其对结肠癌细胞迁移侵袭能力的影响

Expression of ANGPTL2 in colorectal cancer and its influence on invasion and migration of colon cancer cells

目的:探讨ANGPTL2基因在结肠直肠癌组织和细胞中的表达,以及沉默ANGPTL2后对结肠癌细胞迁移、侵袭能力的影响。方法:分别应用实时定量RT-PCR、ELISA观察ANGPTL2在结肠直肠癌组织和细胞中的表达水平;siRNA瞬时转染SW1116细胞株后,半定量RT-PCR筛选干扰效率最高的片段,并用ELISA检测基因沉默效果;transwell小室检测ANGPTL2基因表达下调后对细胞迁移、侵袭能力的影响。结果:45例病人中,癌组织中ANGPTL2蛋白浓度显著高于相应癌旁正常黏膜组织[(36.9±19.3)ng/mL比(5.8±4.2)ng/mL,P<0.001];癌组织中ANGPTL2mRNA的表达量亦高于正常黏膜组织(1.7±1.1比0.7±0.6,P<0.001)。进展期(Ⅲ、Ⅳ期)、有淋巴结转移者的ANGPTL2 mRNA表达量高于早期(Ⅰ、Ⅱ期)、无淋巴结转移者(P<0.001)。ANGPTL2在SW1116细胞中表达最高。SW1116细胞ANGPTL2基因表达下调后,与空白对照组、阴性对照组相比,干扰组细胞迁移、侵袭至下室的SW1116细胞数目减少(P<0.001)。结论:ANGPTL2在结肠直肠癌组织中的表达显著高于癌旁正常黏膜上皮,并与结肠直肠癌的分期、淋巴结转移相关;沉默ANGPTL2基因能显著抑制肿瘤细胞的迁移和侵袭能力。

Objective To investigate the expression of angiopoietin-like protein 2 （ANGPTL2） in colorectal cancer （CRC） tissues and cells, and the effect of ANGPTL2 gene silencing on cell migration and invasion in colon cancer cells. Methods The expression of ANGPTL2 in CRC tissues and colon cancer cells were detected by real time RT-PCR and ELISA. ANGPTL2 silencing in SWl116 cells was achieved by transient transfection with siRNA targeting ANGPTL2 gene and the mRNA and protein expressions of ANGPTL2 were determined by semi-quantitative RT-PCR and ELISA. The effect on cell migration and invasion were investigated with transwell experiment. Results Among the 45 cases, the expressions of ANGPTL2 protein were significantly higher in CRC tissues than the corresponding para-cancerous tissues [（36.9＋19.3） ng/mL vs. （5.8-＋4.2） ng/mL, P〈0.001]. The expression level of ANGPTL2 mRNA was also significantly higher in CRC tissues than in the corresponding para-cancerous tissues （1.7-＋1.1 vs. 0.7-＋0.6, P〈0.001）. The expression of ANGPTL2 mRNA in cases with advanced stages （]]I and IV） or lymph node metastasis were higher than that in cases with earlier stages （ I and ]] ）, or non-lymph node metastasis （P〈0.001）. SWlll6 cell line had the highest level of ANGPTL2 expression. After silencing ANGPTL2 in SW1116 cell line, the number of cells migrating and invading across the transwell charmber was significantly lower in the ANGPTL2 siRNA interference group than those in the negative control group and blank control group （P〈0.001）. Conclusions The expressions of ANGPTL2 is significantly higher in CRC tissues than in the corresponding para-cancerous tissues. Its mRNA expression is associated with the lymph node metastasis and TNM stage. The migration and invasion can be inhibited after silencing ANGPTL2 gene.