We previously found that the hypoxia-inducible genes LOX and AKAP12 played critical roles in tumor invasion and metastasis in breast cancer or melanoma14,15 Using esiRNAs to specifically inhibit each of these fifty genes we identified MAFF as a hypoxia-induced gene, which had the most dramatic effect on tumor cell invasion when inhibited. The gene discussed is SESN2; the disease is breast carcinoma.