Expression of MMP-2, MMP-7, MMP-9, and TIMP-1 by Inflamed Mucosa in the Initial Diagnosis of Ulcerative Colitis as a Response Marker for Conventional Medical Treatment.

INTRODUCTION

Experimental and clinical data involve matrix metalloproteases (MMPs) and their tissue inhibitors (TIMPs) in the pathogenesis of inflammatory bowel diseases. However, the impact of MMPs/TIMPs expression by inflamed mucosa on medical response therapy has scarcely been investigated.

METHODS

The expression of MMP-2, MMP-7, MMP-9, and TIMP-1 was determined by immunohistochemical analysis in inflamed mucosa samples at diagnosis in 82 patients with ulcerative colitis (UC; 22 never-treated with corticosteroids, 28 nonresponders, and 32 responders to corticosteroid therapy) and 15 patients with acute diverticulitis (AD). The global expression (score value) of each factor was analyzed by computer-generated image analysis.

RESULTS

UC samples showed higher MMP-2 and MMP-9 expression but lower TIMP-1 expression than the AD samples (p < 0.0001, for all). High MMP-9 and TIMP-1 scores were significantly associated with no need for corticosteroid treatment (p < 0.001 and p = 0.017, respectively); whereas higher score in the MMP-7 expression was significantly associated with nonresponse to corticosteroid therapy (p = 0.037). In addition, in this latter UC subgroup, MMP-7 correlated positively with the younger age of the patients and with the extension of the disease (p = 0.030 and p = 0.010, respectively).

CONCLUSION

Our results suggest the relevance of MMPs and TIMPs for predicting treatment response to both 5-aminosalicylates and corticosteroids in UC.