Effects of miRNA-21 on paclitaxel-resistance inhuman breast cancer cells
10.3785/j.issn.1008-9292.2015.07.09
- VernacularTitle:微小 RNA－21对人乳腺癌细胞株紫杉醇耐药性的影响及其机制
- Author:
Zun-Lan ZHAO
1
;
Ying CAI
;
Yang-Yang WANG
;
Chun-Lei XIA
;
Cong-Xin LI
;
Su-Lian CHEN
;
Qing-Ling YANG
;
Chang-Jie CHEN
Author Information
1. 蚌埠医学院临床检验诊断学实验中心
- Keywords:
Breast neoplasms;
Paclitaxel/administration & dosage;
MicroRNAs;
Drug resistance,neoplasm
- From:
Journal of Zhejiang University. Medical sciences
2015;(4):400-409
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To investigate the effects of miR-21 on paclitaxel-resistance in human breast cancer MCF-7/PR and SKBR-3/PR cells. Methods: Paclitaxel-resistant human breast cancer cell lines MCF -7P/R and SKBR-3/PR were established by stepwise selection in increasing concentration of paclitaxel .Cellular morphology, mRNA and protein level of MDR1 , BCRP and MRP1 in MCF-7/PR and SKBR-3/PR cells were determined.The expression of Bax, Bcl-2 and miR-21 in parental and paclitaxel-resistant cells was detected by RT-PCR and Western blotting.The synthetic miR-21 inhibitor or miR-21 mimic were transfected into MCF-7/PR, SKBR-3/PR and MCF-7, SKBR-3 cells with Lipofectamine 2000.The miR-21 levels were determined by RT-PCR, and P-gp, Bcl-2 and Bax protein levels were examined by Western blotting. MTT assay was used to measure the cell viability, and flow cytometry was performed to analyze the cell cycle and apoptosis.Results: The levels of MDR1, BCRP, MRP1, Bcl-2/Bax and miR-21 in MCF-7/PR and SKBR-3/PR cells were significantly higher than those in MCF-7 and SKBR-3 cells.The protein levels of P-gp, Bcl-2 were up-regulated, and Bax was down-regulated compared with parental cells.MiR-21 was significantly down-regulated after miR-21 inhibitor was transfected; and the levels of MDR1, BCRP, MRP1 and Bcl-2/Bax (P<00.5) were also down-regulated.MiR-21 inhibitors significantly suppressed G 0/G 1 transition of the cell cycle, and induced cell apoptosis in MCF-7/PR and SKBR-3/PR cells. MTT results showed that miR-21 inhibitors induced sensitivity of MCF-7/PR and SKBR-3/PR cells to paclitaxel.And miR-21 mimic can increase the expression of MDR1, Bcl-2/Bax and change cell morphology from parental cells to resistant cells.Results: The established MCF-7/PR and SKBR-3/PR breast cancer cells show typical multidrug resistance characteristics, which can be used as the model for drug resistance study.Down-regulated miR-21 expression in MCF-7/PR and SKBR-3/PR breast cancer cells can enhance cell sensitivity to paclitaxel.
