Search for: [Abstract = "Breast cancer is the most common neoplasm among women. The main cause of patient’s death are metastases. Process of creation a distant metastasis is determined by different proteolytic enzymes, including matrix metalloproteinases \(MMPs\). MMPs are a group of zinc\-dependent peptidases which catalyse proteolysis of extracellular matrix components. The aim of this study was to determine the activity of MMP\-2 and \-9 in tumor and non tumor breast tissue. The protein and mRNA expression levels were also examined. Another aim of the study was to determine the correlation between the activity of MMP\-2 and \-9 in tumor tissue and the degree of neoplastic lesions progression as classified according to the Bloom Richardson classification. Surgical specimens of the breast tumor tissue were obtained from women diagnosed with breast cancer. The control group consisted of healthy tissue specimens of mammary gland obtained from the same patients. MMP\-2 and \-9 activities were determined by zymography. Protein expression of MMP\-2, \-9 and collagen type IV were evaluated by Western blot. The mRNA expression of MMP\-2 and \-9 was assessed by RT\-PCR. Increased activity of MMP\-2 and \-9 was observed in tumor tissue in comparision with non tumor breast tissue. The increased activity of MMP\-2 correlated with the stage of neoplastic lesions and was higher in tissues derived from neoplastic lesions classified"]
