miR-373在视网膜母细胞瘤Y79细胞中的表达及其抑制侵袭及迁移能力的实验研究

目的　观察miR-373在视网膜母细胞瘤（retinoblastoma，RB）细胞中的表达及其对RB Y79细胞侵袭及迁移能力的影响和相关机制。方法　采用实时荧光定量PCR（qRT-PCR）检测miR-373在RB细胞系RB Y79、SO-RB50和人正常视网膜血管内皮细胞系ACBRI-181中的表达水平，并应用脂质体转染法将miR-373 抑制物（miR-373抑制物组）和阴性对照（NC组）分别转染至Y79细胞，Transwell实验检测Y79细胞侵袭和迁移能力的变化，Western blot检测Y79细胞中上皮间质转化（epithelial-mesenchymal transition，EMT）相关标志物E-Cadherin、Vimentin和N-Cadherin蛋白的表达变化。结果　qRT-PCR 结果显示，RB细胞系Y79、SO-RB50中miR-373的相对表达量分别为6.21±0.34、5.40±0.38，明显高于人正常视网膜血管内皮细胞系ACBRI-181中miR-373的相对表达量（1.02±0.04）（均为P＜0.05）。Transwell实验显示，miR-373抑制物组迁移细胞数（74±13）个，明显低于NC组（180±17）个（P＜0.05），miR-373抑制物组侵袭细胞数（51±9）个明显低于NC组（113±14）个（P＜0.05）。Western blot结果显示，miR-373抑制物组E-Cadherin蛋白的表达（0.40±0.08）明显高于NC组（0.20±0.06）（P＜0.05），Vimentin蛋白的表达（0.17±0.06）也明显低于NC组（0.51±0.10）（P＜0.05），N-Cadherin蛋白的表达（0.12±0.06）也明显低于NC组（0.33±0.08）（P＜0.05）。结论　miR-373在RB细胞中表达异常增高，降低miR-373的表达能够通过调控EMT抑制RB Y79细胞的侵袭和迁移能力，为RB的靶向治疗提供了新的潜在靶点。

Expression of miR-373 in retinoblastoma Y79 cells and its inhibitory effect on cell invasion and migration

Objective　To investigate the expression of miR-373 in retinoblastoma （RB） cells，and its effect on the invasion and migration of RB Y79 cell as well as the relevant mechanisms.Methods　Quantitative real-time polymerase chain reaction （qRT-PCR） was used to detect the expression of miR-373 in RB cell lines，RB Y79 and SO-RB50，as well as human normal retinal vascular endothelial cell line，ACBRI-181.miR-373 inhibitor （miR-373 inhibitor group） and inhibitor-NC （NC group） were separately transfected into Y79 cells using liposome transfection.Afterwards，Transwell assay was utilized to determine the changes of invasion and migration of Y79 cells.Western blot was used to detect the expressions of epithelial-mesenchymal transition （EMT） markers，including E-Cadherin，Vimentin and N-Cadherin，in Y79 cells.Results　The results of qRT-PCR showed that the relative expression of miR-373 in the RB cell line，Y79 and SO-RB50，was 6.21±0.34 and 5.40±0.38，respectively，which was significantly higher than that in the normal retinal vascular endothelial cell line ACBRI-181（1.02±0.04）（both P<0.05）.The Transwell test showed that the number of migratory cells in the miR-373 inhibitor group （74±13） was significantly lower than that of the NC group （180±17） （P<0.05），and the number of invasive cells in the miR-373 inhibitor group （51±9） was significantly lower than that of the NC group （113±14） （P<0.05）.The results of Western blot showed that the expression of E-Cadherin protein in the miR-373 inhibitor group （0.40±0.08） was significantly higher than that in the NC group （0.20±0.06） （P<0.05），and the expression of Vimentin protein （0.17±0.06） was also significantly lower than that of the NC group （0.51±0.10） （P<0.05），and the expression of N-Cadherin protein （0.12±0.06） was also significantly lower than that of NC group （0.33±0.08） （P<0.05）.Conclusion　The expression of miR-373 abnormally increases in RB cells.Down-regulation of miR-373 expression can inhibit the invasion and migration abilities of RB Y79 cells by the regulation of EMT，which provids a novel potential target for targeted therapy of RB.