TWIST1 and breast cancer: To explore the functions of Twist in breast cancer and investigate whether the alteration of Twist has an effect on the expression of MMP-2 and MMP-9, we determined the expression of Twist, MMP-2 and MMP-9 proteins in 200 breast cancer tissue specimens by immunohistochemical (IHC) assay, and studied the correlation between Twist expression and clinicopathological characteristics in the breast cancer tissue samples.