Elevated expression of the CCNA1 gene and protein has been reported in various tumor conditions, such as PTC [21] when associated with pituitary homeobox 2 (PITX2) transcriptional factor, breast cancer [22] when associated with Six1 homeoprotein, prostate cancer [23], leukemic myeloid [24] and ovarian cancer [25]. This evidence concerns the gene PITX2 and breast cancer.