hnRNPE2诱骗RNA逆转32D-BCR-ABL细胞四倍性的研究

Reversion tetraploidy of 32D-BCR-ABL cells by hnRNP E2 decoy RNA

目的初步探讨多聚胞嘧啶结合蛋白E2(hnRNPE2)诱骗RNA对逆转细胞的四倍体特性的作用。方法取32Dcl3细胞(小鼠正常髓母细胞),32D-BCR-ABL细胞(含人类bcr-ablcDNA的转化细胞),32DP210-pGD细胞和32DP210-pGM细胞(表达hnRNPE2诱骗RNA野生型序列pGD和突变性序列pGM的32D-BCR-ABL细胞)作为研究对象。采用流式细胞仪进行细胞的DNA倍体测定;对细胞进行染色体计数,确定染色体核型;采用Western blotting检测细胞cyclinB1和p53蛋白的表达。结果所有32Dcl3均为含40条正常染色体的二倍体细胞,32DP210-pGD细胞中,75.83%以上为二倍体细胞群;32DP210-pGM细胞与32D-BCR-ABL细胞内分别含81.25%和85.81%的四倍体细胞,含80条染色体。与32D-BCR-ABL细胞相比,32DP210-pGD细胞的cyclinB1蛋白水平表达下调,p53蛋白水平无明显变化;32DP210-pGM细胞的cyclinB1和p53蛋白表达均无明显变化。结论 hnRNPE2诱骗RNA能逆转32D-BCR-ABL细胞的四倍体特性。

Objective To investigate the effects of heterogeneous nuclear ribonucleoprotein E2 （hnRNP E2） decoy RNA on reverse tetraploidy of 32D-BCR-ABL cells. Methods Three cell lines,32Dcl3,32DP210-pGD and 32DP210-pGM,were obtained. 32Dcl3 was normal myeloblast of mouse,and 32D-BCR-ABL was the transformant containing human bcr-abl gene. 32DP210-pGD and 32DP210-pGM were established on the basis of 32D-BCR-ABL,expressing pGD and pGM （the wild-type and mutated sequence of hnRNP E2 decoy RNA）. DNA ploidy was analyzed by flow cytometry. The chromosome number was counted and karyotype was determined. The expressions of cyclin B1 and p53 were detected by Western blotting. Results The normal diploidy chromosome cells （2n=40） were found in all the 32Dcl3 cells,as well as in more than 75.83% of 32DP210-pGD cells,while the tetraploid chromosomes （2n=80） were found in 81.25% of 32DP210-pGM cells and 85.81% of 32D-BCR-ABL cells. As compared with 32D-BCR-ABL cells,the expression of cyclin B1 was down-regulated in 32DP210-pGD cells without any significant changes in the expression of p53,while no significant difference was found in both cyclin B1 and p53 expressions in 32DP210-pGM cells. Conclusion hnRNP E2 decoy RNA may reverse the tetraploidy of 32D-BCR-ABL cells.