[Overexpression of miR-30a Promotes Apoptosis of Leukemia K562 Cells].

ABSTRACT

OBJECTIVE: To investigate the pro-apoptotic effect and mechanism of miR-30a overexpression on chronic myeloid leukemia K562 cells. METHODS: The k562 cells were transfected with the recombinant plasmid pEGFP-pre-miR-30a, the real-time quantitative PCR was used to detect the level of miR-30a and BCR/ABL, and then the cell apoptosis was assessed by flow cytometry with AnnexinV-FITC/PI double staining. Western blot was used to detect the expression of BCR/ABL protein,apoptosis-related protein BCL-2 and BAX, PTEN, AKT and p-AKT. RESULTS: Sequencing and digestion map indicated that the recombinant plasmid was constructed successfully. Compared with 2 control groups, the miR-30a expression in k562 cells transfected with recombinant plasmid pEGFP-pre-miR-30a was obviously up-regulated. The expression of BCR/ABL mRNA and BCR/ABL protein was both significantly down-regulated. Apoptotic rate was significantly enhanced (both P<0.05),and the expression of anti-apoptotic protein BCL-2 was down-regulated while the expression of pro-apoptotic protein BAX was up-regulated. The level of PTEN was significantly up-regulated in omparison with control groups,no variation was found in total AKT, but the expression of p-AKT was down-regulated. CONCLUSION: The overexpression of miR-30a is abled to down-regulate the level of BCR/ABL mRNA and BCR/ABL protein, and increase apoptotic rate, its mechanism may be related with inhibition of the activity of BCR/ABL-PTEN/AKT signaling pathway.