ABCB5-ZEB1 Axis Promotes Invasion and Metastasis in Breast Cancer Cells.

ABCB5 belongs to the ATP-binding cassette (ABC) superfamily, which is recognized for playing a role in the failure of chemotherapy. ABCB5 has also been found to be overexpressed at the transcriptional level in a number of cancer subtypes, including breast cancer. However, the exact mechanism ABCB5 uses on cancer cell metastasis is still unclear. In the present study, we demonstrate that ABCB5 expression was increased in metastatic tissues when compared with nonmetastatic tissues. ABCB5 can significantly enhance metastasis and epithelial-mesenchymal transition (EMT), while knockdown of ABCB5 inhibited these processes. Microarray analysis indicated that ZEB1 may function as a downstream factor of ABCB5. Furthermore, the expression of ZEB1 in tissues is positively relevant to ABCB5 in breast cancer. Knocking down ZEB1 inhibits ABCB5 ectopic expression-induced migration and invasion, as well as EMT. Taken together, these results helped to realize the oncogene functions of ABCB5 in breast cancer cells and provided a new direction in treating breast cancer.