微小RNA-101对人骨肉瘤细胞自噬和侵袭性的影响

目的 探讨微小RNA-101（microRNA-101，miR-101）的表达对人骨肉瘤细胞自噬和侵袭性的影响。方法 采用实时荧光定量PCR（qRT-PCR）检测骨肉瘤组织和人骨肉瘤细胞系MG-63细胞以及成骨细胞miR-101的相对表达，蛋白免疫印迹(Western blot)检测两种细胞自噬相关蛋白Beclin1和LC3B的表达；经脂质体转染将miR-101模拟物和miR-101阴性对照转染MG-63细胞，并设立空白对照，通过qRT-PCR、Western blot和侵袭实验（Transwell）检测以上三组细胞miR-101的表达、Beclin1和LC3B的表达以及三组细胞侵袭能力的变化。结果 与癌旁骨组织和正常骨组织或成骨细胞相比，miR-101在骨肉瘤组织和MG-63细胞中表达明显下降（P<0.01）；模拟物转染组miR-101的表达较空白对照组上调了255%，但该组自噬相关蛋白的表达较空白组却显著降低（P<0.01）；Transwell侵袭实验显示，模拟物转染组细胞迁移数目较阴性对照组和空白对照组分别减少了60%和67.67%（P<0.01）。结论 miR-101在骨肉瘤组织和骨肉瘤细胞中呈现低表达，可能与骨肉瘤的发生发展相关。miR-101抑制骨肉瘤细胞侵袭，其机制可能是通过抑制细胞自噬而发挥作用。

Effects of microRNA-101 on Invasion and Autophagy of Human Osteosarcoma Cells

Objective To investigate the effect of miR-101 expression on invasion and autophagy ofosteosarcoma cell line MG-63. Methods qRT-PCR was applied to detect miR-101 expression in humanosteosarcoma tissues, MG-63 cells and osteoblasts. Western blot was used to measure the protein expressionof Beclin1 and LC3B. Moreover, MG-63 cells were randomly divided into three groups by means oflipofectamine transfection: miR-101 mimics group, negative control group and blank control group. Aftertransfection, miR-101 expression was detected by qRT-PCR, protein levels were measured by Western blot,and Transwell migration assay was used to examine the invasive capacity of MG-63 cells. Results miR-101expression levels in osteosarcoma tissues and MG-63 cells were significantly decreased, compared with thosein normal bone tissues, adjacent bone tissues and osteoblast (P<0.01). Compared with blank control group,miR-101 expression in miR-101 mimics group was up-regulated significantly by 255%, but the proteinsexpression of Beclin1 and LC3B were obviously decreased (P<0.01). Meanwhile, Transwell migrationassay showed that the numbers of migrated cells in miR-101 mimics group were decreased by 60% and67.67% compared with those in negative control group and blank control group, respectively (P<0.01).Conclusion miR-101 expression was down-regulated significantly in osteosarcoma tissues and MG-63 cells,which may be involved in the occurrence and development of osteosarcoma. miR-101 could dramaticallyinhibit Beclin1 and LC3B protein expression and retard the invasion of osteosarcoma MG-63 cells, and themechanism may be achieved by inhibiting autophagy.