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目的:观察微小RNA-21(miR-21)对胰腺癌PANC1细胞侵袭、迁移和凋亡的影响，探讨其可能的作用机制。方法:构建插入miR-21或靶向miR-21的小干扰RNA的重组质粒，以空质粒为对照，应用脂质体法分别转染人胰腺癌PANC1细胞，建立空白组、miR-21过表达组(过表达组)和miR-21沉默组(沉默组)PANC1细胞株，采用MTT法检测细胞增殖率，流式细胞仪检测细胞凋亡，Transwell小室检测细胞侵袭能力，划痕试验检测细胞迁移能力，酶联免疫法检测miR-21靶向结合的程序性细胞死亡因子4(PDCD4)蛋白的表达，蛋白质免疫印迹法检测磷酸酶和张力蛋白同源基因(PTEN)、血管内皮生长因子(VEGF)、survivin、基质金属蛋白酶2(MMP-2)和MMP-9蛋白表达。结果:培养24 h时，空白组、过表达组、沉默组细胞增殖率分别为(20.72±5.62)%、(28.46±6.12)%、(14.05±3.36)%；细胞凋亡率分别为(5.89±0.26)%、(4.62±0.19)%、(8.66±2.25)%；穿膜细胞数分别为(212.4±32.5)、(508.8±50.7)、(50.9±10.6)个/200倍视野；细胞迁移覆盖面积分别为(75.6±12.1)、(118.8±20.2)、(48.8±9.5)mmn 2/200倍视野；PDCD4表达量为0.85±0.22、0.72±0.10、1.36±0.41；PTEN表达量为0.85±0.21、0.28±0.09、1.36±0.45；VEGF表达量为0.79±0.24、1.15±0.31、0.46±0.10；survivin为1.02±0.33、1.51±0.42、0.52±0.12；MMP-2为1.12±0.22、1.86±0.52、0.56±0.18；MMP-9为1.06±0.15、1.78±0.48、0.49±0.12，3组间的差异均有统计学意义(n P值均<0.05)。与空白组比较，沉默组的细胞凋亡率及PDCD4、PTEN表达量均增加，而细胞增殖、侵袭、迁移能力以及VEGF、survivin、MMP-2、MMP-9蛋白表达量均下降；过表达组的变化与沉默组完全相反，过表达组、沉默组与空白组的差异均有统计学意义(n P值均<0.05)。n 结论:沉默miR-21能抑制PANC1细胞的增殖、迁移和侵袭力，促进细胞凋亡，其机制可能与上调PDCD4及PTEN蛋白表达有关。“,”Objective:To observe the effects of microRNA-21 (miR-21) on cell invasion, migration and apoptosis of pancreatic cancer PANC1 cells, and explore the potential molecular mechanism.Methods:Recombinant plasmids carrying miR-21 or small interfering RNA targeting miR-21 were constructed. Using blank plasmid as the control, the recombinant plasmids were transfected with human pancreatic cancer PANC1 cells by liposome method, respectively to establish blank group, miR-21 overexpression group (overexpression group) and miR-21 silence group (silence group) PANC1 cell lines. Cell proliferation, apoptosis, invasion and metastasis were detected by MTT method, flow cytometry, transwell chamber and wound scratch test, respectively. ELISA and Western blot were used to measure the protein expression of programmed cell death factor 4(PDCD4), gene of phosphate and tension homology deleted on chromsome ten (PTEN), vascular endothelial growth factor (VEGF), survivin, matrix metalloproteinase 2 (MMP-2) and MMP-9.Results:After 24 h cell culture, the cell proliferation rate of blank group, overexpression group and silence group was (20.72±5.62)%, (28.46±6.12)% and (14.05±3.36 )%; cell apoptosis rate was (5.89±0.26)%, (4.62±0.19)% and (8.66±2.55)%; the number of transmembrane cells was (212.4±32.5), (508.8±50.7) and (50.9±10.6) per 200 times visual field; the area covered by migrated cells was (75.6±12.1), (118.8±20.2) and (48.8±9.5)mmn 2 per 200 times visual field; the expression of PDCD4 was 0.85±0.22, 0.72±0.10 and 1.36±0.41; the expression of PTEN was 0.85±0.21, 0.28±0.09 and 1.36±0.45; the expression of VEGF was 0.79±0.24, 1.15±0.31 and 0.46±0.10; the expression of survivin was 1.02±0.33, 1.51±0.42 and 0.52±0.12; the expression of MMP-2 was 1.12±0.22, 1.86±0.52 and 0.56±0.18; the expression of MMP-9 was 1.06±0.15, 1.78±0.48 and 0.49±0.12. All the differences among the three groups were statistically significant (all n P<0.05). Compared with blank group, the cell apoptosis rate, PDCD4 and PTEN expression were increased, while cell proliferation, invasion and migration, and the protein expression of VEGF, survivin, MMP-2 and MMP-9 were all decreased; the changes in silence group was totally contrary to those in overexpression group. All the differences among the three groups were statistically significant (alln P<0.05).n Conclusions:miR-21 silencing can inhibit the proliferation, migration and invasion of PANC1 cells and promote apoptosis, and the mechanism was possibly associated with the upregulation of PDCD4 and PTEN protein expression.