Decreased expression of tumor-suppressor genes such as ATM serin/threonine kinase, paired-like homeodomain transcription factor, Ras-association domain family 1, isoform A, Phosphatase and tensin homolog, and Tissue inhibitor of metalloproteinase-3 is frequently observed in patients with BC [81] or in cancer models [7]. This evidence concerns the gene PTEN and cancer.