Intraepithelial matrix metalloproteinase-9 in invasive breast carcinoma, normal tissue adjacent to tumor, and normal mammoplasty specimens: a comparative study considering relationship between matrix metalloproteinase-9 and some clinicopathologic prognostic factors of breast carcinoma

Abstract Background- Matrix metalloproteinase-9 (MMP-9), an enzyme with major role in remodeling of extracellular matrix, has been the focus of attention in some previous studies in the field of breast cancer. We conducted a comparative study to investigate the frequency of this marker in tissue specimens of invasive breast carcinoma, tumor control, and normal control. The relationship between matrix metalloproteinase-9 and some clinicopathologic factors of breast carcinoma has also been evaluated. Methods- Formalin-fixed and paraffin-embedded tissue specimens from three groups including 40 invasive breast carcinoma (tumor group) and their adjacent normal tissue (tumor control), as well as 40 normal mammoplasty specimens (normal control) were studied. The samples were from the pathology archive of Alzahra Hospital, Isfahan, Iran, from 2016 to 2018. The status of intraepithelial MMP-9 was studied and compared in these three groups using immunohistochemistry. The relationship between intraepithelial MMP-9 and some clinicopathologic prognostic factors was also evaluated in tumor group. Results - The extent of intraepithelial MMP-9 immunostaining in all positive specimens was 100%. The results of intraepithelial MMP-9 staining intensity was as follow: 12.5% strong, 27.5% moderate, 27.5% mild, and 32.5% negative in tumor group; 17.5% strong, 22.5% moderate, 32.5% mild, and 27.5% negative in tumor control group; and 10% strong, 40% moderate, 27.5% mild, and 22.5% negative in normal control group. Intraepithelial MMP-9 immunostaining intensity showed significant difference between tumor and tumor control groups (P0.05).