As shown in Table 1, MCF-7 cells are the non-metastatic breast cancer cells and express ER-α while MDA-MB-231 cells have metastatic potentials and lack the expression of ER-α [40], and T47D is ER-α positive cell line but express low level of endogenous VEGF and cyclin A1. This evidence concerns the gene CCNA1 and breast cancer.