High levels of MMP-9 have been found in various types ofcancers, and it is thought to contribute to the spread of cancer cells by breakingdown the extracellular matrix, allowing the cells to invade surrounding tissues.MMP9 plays a crucial role in the final differentiation of human endometrial stromalcells into decidual cells (Fisher, 2004; Seval et al., 2004). This evidence concerns the gene MMP9 and cancer.