Gupta et al. used genetic and pharmacological agents for inactivation of four genes, as the EGFR ligand epiregulin, COX-2, and two metalloproteinases (MMP1 and 2) and demonstrated a repression of primary tumor growth, tumor cell intra- und extravasation as well as metastatic outgrowth [26]. The gene discussed is MMP1; the disease is neoplasm.