miR-181a sensitizes a multidrug-resistant leukemia cell line K562/A02 to daunorubicin by targeting BCL-2  

作　　者：Hao Li Lulu Hui Wenlin Xu 

机构地区：[1]Department of Central Laboratory,The Affiliated People's Hospital,Jiangsu University,Zhenjiang 212001,China

出　　处：《Acta Biochimica et Biophysica Sinica》2012年第3期269-277,共9页生物化学与生物物理学报（英文版）

摘　　要：The aim of this study was to investigate whether miR-181a could modulate the sensitivity of the leukemia drug- resistant cell line K562/A02 to the chemotherapeutic agent daunorubicin （DNR）, and explore the mechanism of miR- 181a on the DNR sensitivity of K562/A02 ceils. MicroRNA microarray and stem-loop reverse transcription-polymer- ase chain reaction were used to detect the expression of miR-181a. The 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl- 2H-tetrazolium bromide assay was performed to quantify the effect of miR-181a on K562 cells growth and viability. Apoptotic cells were quantitatively detected using Annexin V/FITC and PI apoptosis detection kit. BCL-2 protein expression was measured by western blot. Luciferase reporter vector with the putative BCL-2 3/ untranslated region was constructed to explore whether BCL-2 was a direct target gene of miR-181a. BCL-2 siRNA was trans- fected into the cell to explore the relationship between BCL-2 and DNR resistance. The miR-181a expression level was lower in the K562/A02 cells than in the K562 cells （P 〈 0.05）. K562 cells that were transfected with miR-181a inhibitor had a significantly higher survival than K562 cells, and K562/A02 cells that were transfected with the miR-181a mimic had a significantly lower survival than K562/A02 cells （P 〈 0.05）. miR-181a could enhance DNR- induced apoptosis in K562/A02 cells. BCL-2 siRNA trans- fected K562/A02 cells had decreased survival compared with the K562/A02 control group. In conclusion, miR-181a could play a role in the development of DNR resistance in K562/A02 cells and the over-expression of miR-181a could sensitize K562/A02 cells to DNR by targeting BCL-2.The aim of this study was to investigate whether miR-181a could modulate the sensitivity of the leukemia drug- resistant cell line K562/A02 to the chemotherapeutic agent daunorubicin （DNR）, and explore the mechanism of miR- 181a on the DNR sensitivity of K562/A02 ceils. MicroRNA microarray and stem-loop reverse transcription-polymer- ase chain reaction were used to detect the expression of miR-181a. The 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl- 2H-tetrazolium bromide assay was performed to quantify the effect of miR-181a on K562 cells growth and viability. Apoptotic cells were quantitatively detected using Annexin V/FITC and PI apoptosis detection kit. BCL-2 protein expression was measured by western blot. Luciferase reporter vector with the putative BCL-2 3/ untranslated region was constructed to explore whether BCL-2 was a direct target gene of miR-181a. BCL-2 siRNA was trans- fected into the cell to explore the relationship between BCL-2 and DNR resistance. The miR-181a expression level was lower in the K562/A02 cells than in the K562 cells （P 〈 0.05）. K562 cells that were transfected with miR-181a inhibitor had a significantly higher survival than K562 cells, and K562/A02 cells that were transfected with the miR-181a mimic had a significantly lower survival than K562/A02 cells （P 〈 0.05）. miR-181a could enhance DNR- induced apoptosis in K562/A02 cells. BCL-2 siRNA trans- fected K562/A02 cells had decreased survival compared with the K562/A02 control group. In conclusion, miR-181a could play a role in the development of DNR resistance in K562/A02 cells and the over-expression of miR-181a could sensitize K562/A02 cells to DNR by targeting BCL-2.

关 键 词：miR- 181 a apoptosis BCL-2 

分 类 号：Q786[生物学—分子生物学] O614.33[理学—无机化学]