In this report, we provided evidences that activation of the Notch-1 signaling pathway (1) promoted the malignant phenotype of human breast cancer line, MDA-MB-231 cells, (2) activated NF-κB signaling pathway, and (3) up-regulated the expression of NF-κB target genes including MMP-2/-9 and VEGF that are known to facilitate tumor invasion and metastasis. The gene discussed is MMP2; the disease is breast cancer.