Comparative expression of matrix metalloproteinases in internal malignancies and paired cutaneous metastatic lesions

Matrix metalloproteinase (MMP), tissue inhibitor of metalloproteinase (TIMP), and membrane-type 1 matrix metalloproteinase (MT1-MMP) are thought to be involved in the destruction of basement membrane and stromal invasion by cancer cells. The aim of this study was to identify and compare MMP and TIMP expression in internal malignancies and paired cutaneous metastatic lesions. We compared the expression of MMP-2, MMP-9, MT1-MMP, and TIMP-2 in the internal malignancy and paired cutaneous metastatic lesion using immunohistochemical stains. The cutaneous metastatic lesions expressed significantly more MMP-2, MMP-9, and MT1-MMP and significantly less TIMP-2 than did the paired internal malignancies. In breast cancer, cutaneous metastatic lesions expressed significantly more MMP-9 and significantly less TIMP-2 than did the primary breast cancer lesion. In lung cancer, the cutaneous metastatic lesion expressed significantly more MMP-2 and MT1-MMP than did the primary lesion. In stomach cancer, the cutaneous metastatic lesion expressed significantly less TIMP-2 than did the primary lesion. Our study demonstrates that cutaneous metastatic lesions have different MMPs and TIMP-2 expression patterns compared with their paired internal malignancies. Also, MMPs and TIMP-2 expression differs according to the type of primary cancer.