Resistance to fluoropyrimidine-based
chemotherapy is the main reason for the failure of
cancer treatment, and drug resistance is associated with an inability of
tumor cells to undergo apoptosis in response to treatment. Alterations in the expression of
epithelial cell adhesion molecule (
EpCAM) affect the sensitivity or resistance of
tumor cells to anticancer treatment and the activity of intracellular signaling pathways. However, the role of
EpCAM in the induction of apoptosis in
breast cancer cells remains unclear. Here, we investigated the effect of
EpCAM gene knockdown on chemosensitivity to
5-fluorouracil (5-FU) in MCF-7 cells and explored the underlying mechanisms. Our results showed that knockdown of
EpCAM promoted apoptosis, inhibited cell proliferation and caused cell-cycle arrest.
EpCAM knockdown enhanced the cytotoxic effect of
5-FU, promoting apoptosis by downregulating the expression of the
anti-apoptotic protein Bcl-2 and upregulating the expression of the
pro-apoptotic proteins Bax, and caspase3 via the ERK1/2 and JNK MAPK signaling pathways in MCF-7 cells. These results indicate that knockdown of
EpCAM may have a
tumor suppressor effect and suggest
EpCAM as a potential target for the treatment of
breast cancer.