STROMAL EXPRESSION OF MMP-9 AND UROKINASE RECEPTOR IS INVERSELY ASSOCIATED WITH LIVER METASTASIS AND WITH INFILTRATING GROWTH IN HUMAN COLORECTAL-CANCER - A NOVEL-APPROACH FROM IMMUNE INFLAMMATORY ASPECT/

MMP-9 (gelatinase B) and urokinase-type plasminogen activator receptor (u-PAR), which are involved in cancer cell invasion and metastasis, a re reported to be predominantly expressed by immune/inflammatory cells in human colorectal cancers, To investigate their significance in can cer progression, we morphometrically analyzed the tissue expression of MMP-9 and u-PAR among different stages of colorectal cancer, The numb ers of MMP-9- and u-PAR-positive cells along the invasive margin were significantly smaller in cases with liver metastasis than in cases wit hout liver metastasis, and were also smaller in cases with an infiltra ting margin than in cases with an expanding margin, Both variables wer e larger in colon cancer cases with conspicuous lymphocytic infiltrati on, These results indicated that the degree of tissue expression of MM P-9 and u-PAR by host cells is inversely associated with liver metasta sis and an infiltrating growth pattern in human colorectal cancers, Es sentially the same results were obtained for the number of macrophages distributed along the invasive margin, We also found that the express ion pattern of MMP-9 was similar to that of MMP-8 (polymorphonuclear l eukocyte collagenase), These data are consistent with clinicopathologi c studies of host cells, Therefore, our data suggest a dual role of MM P-9 and u-PAR expression in colon cancer tissue; i.e., not only are th ese proteinases cancer-promoting factors, but also they are related to the host defensive mechanism when they are expressed by host cells.