Influence of aloe emodin and cisplatin on expression level of Bcl-2 and Bcl-xL in breast cancer MDA-MB-231 cells

Abstract

Objective To investigate the effects of aloe emodin and cisplatin on the expression of Bcl-2 and Bcl-xL in breast cancer MDA-MB-231 cells. Methods Cultured MDA-MB-231 cells were randomly divided into blank control group, aloe emodin group, cisplatin group and combined drug group. Aloe emodin group was given 30 mol/L aloe emodin, while cisplatin group was given 12 mol/L cisplatin, and combined drug group was given 30 mol/L aloe emodin + 12 mol/L cisplatin. Cell proliferation was detected by MTT method. Cell apoptosis and cell cycle were detected by flow cytometry. The expression of Bcl-2 and Bcl-xL protein was detected by Western blot. Results The inhibitory rate of MDA-MB-231 cell proliferation in combined drug group was (68.48±8.75)%, which was significantly higher than that in aloe emodin group [(54.28±8.39)%] and cisplatin group [(52.04±9.11)%], P<0.05. The proportion of G0/G1 cells in combined drug group was [(87.91 ± 9.10)%], which was significantly higher than that in aloe emodin group [(64.21±8.45)%], cisplatin group [(67.08±9.82)%] and blank control group [(56.38±7.93)%], P<0.05. The proportion of G0/G1 cells in aloe emodin group and cisplatin group was significantly higher than that of blank control group (P<0.05). The apoptosis rate of combined drug group was [(17.38 ± 3.20)%], which was significantly higher than that of aloe emodin group (7.84±0.83)%], cisplatin group [(6.90±1.10)%] and blank control group [(0.63±0.07)%], P<0.05. The apoptosis rate of aloe emodin group and cisplatin group was significantly higher than that of blank control group (P<0.05). The relative expression levels of Bcl-2 and Bcl-xL in blank control group were 1.02±0.16 and 1.01±0.17, which were significantly higher than those of aloe emodin group (0.67±0.10, 0.52±0.11), cisplatin group (0.70±0.11, 0.50±0.09) and combined drug group (0.64±0.13, 0.13±0.04), P<0.05. The relative expression of Bcl-xL protein in combined drug group was significantly lower than that in aloe emodin group and cisplatin group (P<0.05). Inhibition rate of MDA-MB-231 cell adhesion fibronectin and laminin in combined drug group were 28.10±4.10 and 30.01±9.82, which were significantly higher than those in aloe emodin group (13.28±3.10, 14.28±6.72) and cisplatin group (14.50±3.32, 15.10±7.08), P<0.05. Inhibition rate of cell invasion of combined drug group was [(54.27±8.83)%], which was significantly higher than that of aloe emodin group [(28.10±8.22)%] and cisplatin group [(30.10±9.10)%], P<0.05. Conclusions Aloe emodin and cisplatin can effectively inhibit the proliferation of MDA-MB-231 cell, arrest cell cycle in G0/G1 phase, and down regulate Bcl-2 and Bcl-xL protein. The combination of them can enhance the role of promoting apoptosis. Key words: Aloe emodin; Cisplatin; MDA-MB-231 cell; Bcl-2; Bcl-xL