Objectives: Breast cancer is one of the most common malignancies in women, and the tumor cells' invasion and metastasis is the main cause of death. Recent reports showed that Twist, a transcription factor, plays multiple roles in breast cancer initiation, progress, and metastasis. However, the underlying mechanisms of Twist in tumor invasion and metastasis of breast cancer still remain unclear. Here, we examined the correlation between Twist, E-cadherin, and estrogen receptor (ER) in promoting invasion and metastasis in breast cancer cells and tissues.
Materials and methods: The mRNA and protein expression of Twist, E-cadherin, and ER in breast cancer cell lines (MCF-7, MDA-MB-435, MDA-MB-231, and ZR-75-30) and human invasive ductal carcinoma (IDC) tissues from 32 patients were detected by reverse transcription-polymerase chain reaction and immunohistochemistry (IHC), respectively.
Results: Expression of Twist in cells with high ability of invasion and metastasis was higher than that in MCF-7 cell line which has low ability of invasion and metastasis, while the expression of ER and E-cadherin was much more higher in MCF-7 cell line than in other cells. IHC showed that the expression rate of Twist in IDC tissues and adjacent tissues was 84.38% and 31.25% and the positive expression of E-cadherin and ER was 21.88% and 40.63% in IDC tissues and 81.25% and 84.38% in adjacent tissues, respectively. Interestingly, overexpression of Twist promoted cellular invasion and metastasis and decreased the expression of E-cadherin, ER, AKT, and p-AKT in HEK-293 cells.
Conclusions: Taken together, these findings demonstrated that Twist was upregulated in high invasion and metastasis cell lines as well as IDC tissues companioned with downregulated expression of E-cadherin and ER, which provides important clues for the deeper study of breast cancer.