Molecular mechanisms underlying proliferation and apoptosis in breast cancer MCF-7 cells induced by pentabrominated diphenyl ethers

The molecular mechanisms underlying proliferation and apoptosis induced by pentabrominated diphenyl ethers (5-BDE) through regulation of mRNA and protein expression of Bcl-2 and Bax was investigated using breast cancer MCF-7 cells. Human breast cancer MCF-7 cells were grown in DMEM medium, MTT assay was employed to investigate cell proliferation. RT-PCR and immunohistochemistry was performed to determine mRNA and protein expression of Bcl-2 and Bax. Within the range of 1 × 10−8–10−4mol L−1, polybrominated diphenyl ethers (PBDE) stimulated proliferation in MCF-7 cells in a concentration- and time-dependent manner. RT-PCR and immunohistochemistry analyses revealed that treatment with PBDE for 72 h resulted in increased mRNA and protein expression of Bcl-2 and inhibition of Bax. Evidence indicates that 5-BDE exerted estrogenic actions and stimulated proliferation in estrogen responsive breast cancer MCF-7 cells via up-regulation of Bcl-2 mRNA and protein expression.