Activity of matrix metalloproteinases -2 and -9 (MMP-2 and MMP-9) and content of their tissue inhibitors in endometrial cancer – a preliminary study

Abstract

Objectives: Matrix metalloproteinases-2 and –9 (MMP-2 and MMP-9) are enzymes degrading collagen type IV and other components of the basement membrane. Their activity is suppressed by tissue inhibitors of metalloproteinases – TIMP-1 and TIMP-2. Substantial evidence indicates that MMP2 and MMP-9 play an important role in the spread of malignant tumours. The aim of the study was to evaluate the activity of MMP-2 and MMP-9 and contents of their inhibitors: TIMP-1 and TIMP-2 in endometrial cancer and normal endometrium. Material and methods: Material for the study comprised 28 samples of endometrial cancers and 15 samples of normal endmetrium. A two-step method for extraction of MMPs was applied. The activity of MMP-2 and MMP-9 was measured with semi-quantitative zymography. TIMP-1 and TIMP-2 contents were measured with ELISA method. Results: Mean activity and activation ratio of MMP-9 was significantly higher in endometrial cancers compared with normal myometrium, whereas mean activity and activation ratio of MMP-2 did not differ significantly between investigated groups. Mean content of TIMP-1 and TIMP-2 did not differ between cancer and control tissues. No unequivocal association between activity of investigated MMPs or contents of their inhibitors and clinicopathological features of endometrial cancers was observed. Conclusions: Results of the study suggest that MMP-9 may play an important role in the progression of endometrial cancer, whereas MMP-2 does not seem to be involved in this process. Action of MMP-9 may be further enhanced by relative deficiency of TIMP-1.