Proteins of the B-cell lymphoma 2 family are crucial for the regulation of apoptosis. B-cell
lymphoma 2-associated X is a pro-apoptotic protein, while B-cell lymphoma 2 protein opposes apoptosis. The influence of 1 μM 2-methoxyestradiol was investigated on the expression levels of these two proteins in
MCF-7 cells. 2-Methoxyestradiol exposure did not influence B-cell lymphoma 2 protein expression levels after 24 h of exposure. In contrast, B-cell lymphoma 2-associated X protein levels were significantly reduced. An improved differential interference contrasting technique revealed compromised cell density and the presence
of a mitotic block in exposed cells. The study proposes that the influence of 2-methoxyestradiol on the expression of these proteins may be time- and cell type dependent and thus not evident during the mitotic block observed. Investigation of the regulation of the B-cell lymphoma 2 family will allow researchers to consider signaling pathways for diseases where apoptosis can potentially be controlled.