Estrogen receptors participate in silibinin-caused nuclear translocation of apoptosis-inducing factor in human breast cancer MCF-7 cells.

Our previous studies showed that silibinin promoted activation of caspases to induce apoptosis in human breast cancer MCF-7 cells by down-regulating the protein expression level of estrogen receptor (ER) α and up-regulating ERβ. Recently, it has been reported that silibinin-induced apoptosis also involved nuclear translocation of apoptosis-inducing factor (AIF). Here we report that silibinin induces nuclear translocation of AIF through the down-regulation of ERα and up-regulation of ERβ in a concentration dependent manner in MCF-7 cells.

Silibinin-induced apoptosis of breast cancer cells involves mitochondrial impairment.

Mitochondria are dynamically regulated by fission and fusion processes. Silibinin induces apoptosis of MCF-7 and MDA-MB-231 human breast cancer cells. However, whether or not mitochondria dysfunction is involved in the apoptosis induction with silibinin of both types of the cells remains unknown.