MMP9 and cancer: In Snail-1-induced EMT, there is a subsided expression of E-cadherin and claudins, which is accompanied with the upmodulation of vimentin and fibronectin.7 Moreover, Snail-1 upregulates MMP-9 and CXCR4, which are central mediators of cancer cells invasion and migration to discrete organs.7,8 It has previously been observed that Snail-1 can control the expression of E-cadherin, vimentin, CXCR4, MMP-9, miR-34a, and let-7, which interferes with the EMT process; hence, it seems that Snail-1 may be a crucial modulator during invasive and metastatic behaviors of tumor cells.9-13