Effects of doxorubicin on the expressions of BRCA1 and PARP-1 proteins in breast cancer MCF-7 cells
10.3781/j.issn.1000-7431.2013.05.001
- Author:
Hui WANG
1
Author Information
1. Department of Pathology
- Publication Type:Journal Article
- Keywords:
Breast neoplasms;
Doxorubicin;
BRCA1 protein;
Poly(ADP-ribose) polymerases;
Gene expression
- From:
Tumor
2013;33(5):385-391
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To investigate the effects of doxorubicin on the expressions of DNA-damage/repair-related proteins BRCA1 (breast cancer-associated protein 1) and PARP-1 [poly(ADP-ribose) polymerase-1] in BRCA1 wild-type breast cancer MCF-7 cells. Methods: The MCF-7 cells were treated with doxorubicin, then the expressions of BRCA1 and PARP-1 and the activity of PARP-1 in the cells recovering after different time peroids were detected by Western blotting. The apoptotic rates of MCF-7 cells and SKBR3.0 cells (BRCA1 mutant-type breast cancer cells) after intervention with doxorubicin and PARP-1 inhibitor 3-ABA (3-aminobenzamide) were detected by FCM (flow cytometry). Results: After MCF-7 cells were treated with different concentrations of doxorubicin for 24 h and then recovered for 12 h, the expression of PAR [poly(ADP-ribose)], an active product of PARP-1, was increased in a dose-dependent manner (P < 0.01), but the expression of full-length PARP-1 (the molecular mass is 1.13×10 5) was in a slightly decrease accompanied by more cleavage fragments of PARP-1 (the molecular mass is 8.9×104), while the expression of BRCA1 was firstly increased and then decreased (P < 0.01). After MCF-7 cells were treated with 1 μmol/L doxorubicin for 24 h and then recovered for different time peroids, the activity of PARP-1 (PAR) was increased gradually over time peroid of recovery (P < 0.01), but the expression of full-length PARP-1 had no significant change with less cleavage fragments of PARP-1, while the expression of BRCA1 was decreased gradually (P < 0.01). The activity of PARP-1 was significantly inhibited by 3-ABA (P < 0.01) via inducing its cleavage, which didn't affect BRCA1 expression (P > 0.05). Both doxorubicin and 3-ABA alone could significantly induce the apoptosis of MCF-7 cells (P < 0.05), and the combination of the two could further increase the apoptosis of BRCA1 wild-type breast MCF-7 cells (P < 0.05). Doxorubicin in combination with 3-ABA could also induce the apoptosis of BRCA1 mutant-type SKBR3.0 cells, and this effect was stronger than that in MCF-7 cells (P < 0.05). Conclusion: Doxorubicin intervention can affect the activity of DNA-damage/repair-related protein PARP-1 and the expression of BRCA1. Both doxorubicin and PARP-1 inhibitor 3-ABA can induce the apoptosis of MCF-7 cells, and the combination of the two can increase this apoptosis-inducing effect. Copyright © 2013 by TUMOR.
