Increased expression of MMP-2 at least partly underlies prostate cancer aggressiveness, while the metastatic potential of PC-3 and LNCaP cells coincides with an increased expression of MMP-9 (which is twofold higher in more invasive PC-3 cells) (Upadhyay et al., 1999[133]; Aalinkeel et al., 2004[1]). Here, MMP9 is linked to prostate cancer.