Although these MT-MMPs may probably play roles in cancer progression, no significant difference was found between patients with invasion vs. without invasion (MT4-MMP: P = 0.419; MT6-MMP: P= 0.168) as well as patients with lymph node metastasis vs. without lymph node metastasis (MT4-MMP: P = 0.606; MT6-MMP: P = 0.216) (Table 3). Here, MT4 is linked to cancer.