癌基因Bmi-1引起中心体扩增的可能机制

 [目的] 探讨Bmi-1引起中心体扩增的可能机制。[方法] 体外建立Bmi-1稳定高表达和Bmi-1–RNAi稳定起作用的细胞株， 采用免疫荧光染色法计数中心体（Microtub）异常复制的比率及定位细胞周期素蛋白D1（cyclinD1）和P27的表达，同时进行Western blot检测cyclinD1和p27在核中的表达量。[结果] Microtub染色计数发现与对照细胞相比，中心体异常复制的比率在6-10B/Bmi-1-1细胞中升高，而在CNE2/Bmi-1-RNAi细胞中下降；免疫荧光染色和Western blot检测均发现cyclinD1蛋白在6-10B/Bmi-1细胞核内表达升高，而在CNE2/Bmi-1-RNAi细胞核内表达降低，P27蛋白则在两株细胞株中均呈现相反的变化。[结论] Bmi-1可能通过调控cyclinD1-P27途径引起中心体扩增。

Possible Mechanism of Centrosomal Amplification Induced by Oncogene Bmi-1

[Objective] To investigate the possible mechanism of centrosomal amplification incuced by oncogene Bmi-1 (B-cell-specific moloney murine leukemia virus integration site 1). [Methods] Immunofluorescence staining were used to calculate the ratio of the abnormal centrosomal dupulication and investigate the location of P27 and cyclin D1 protein; Western blot was performed to detect the expression of p27 and cyclin D1 in nucleus. [Results] By Microtub counting, compared with the control cells, 6-10B/ pMSCV-Bmi-1 showed a higher ratio of abnormal centrosomal dupulication, while the ratio of centrosomal amplification was lower in CNE2/Bmi-1-RNAi cells. Moreover, higher expression of cyclin D1 was detected in nucleus of 6-10B/Bmi-1 cells, while CNE2/Bmi-1-RNAi cells showed lower expression of cyclin D1 in nucleus; meanwhile, P27 was upregulated by Bmi-1 overexpression and downregulated by Bmi-1 RNAi, which was according with the results from immunofluorescence staining. [Conclusions] Bmi-1 may induce centrosomal amplification by regulating cyclin D1-P27 pathway.