Histopathological and immunohistochemical study of matrix metalloproteinase-2 and matrix metalloproteinase-9 in breast carcinoma

Background/aim
Breast cancer is the most harmful tumor among women around the world, with increasing incidence rates. Invasion and metastasis are the most insidious and life-threatening parts of the cancer. Efforts have been made to understand the mechanisms that regulate and facilitate the metastatic process. This step in metastasis of malignant cells requires the association of proteolytic catalysts that degrade protein segment of the extracellular matrix. Matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) are the members of degrading enzymes required in tumor advancement, invasion, and metastasis. This work aims to examine the utility of MMPs in breast carcinoma to assess their usefulness in growth, invasion, and metastasis.
Patients and methods
A total of 60 samples of cases of breast cancer with positive and negative lymph nodes were collected randomly as paraffin blocks which was previously prepared material. The samples from the cases were immunostained for MMP-2 and MMP-9, and their expression was correlated with various clinicopathological parameters.
Results
Most cases of cancer were presented in the age group 51–60 years. The most common type was invasive duct carcinoma Not Otherwise Specified (NOS), representing 70% of cases. Overall, 51 (85%) cases were positive for MMP-2 whereas 54 (90%) cases were positive for MMP-9. Presence of MMP-2 and MMP-9 in peritumoral stroma was in the ratio of 60 and 64%, respectively. Both markers were significantly elevated in malignant tissues of patient with lymph node metastasis as compared with those without lymph node metastasis (=0.029 and 0.048, respectively). The expression of MMP-2 and MMP-9 increased with advanced clinical staging and grading (=0.015 and 0.011).
Conclusion
Expression of MMP-2 and MMP-9 in breast cancer is closely correlated with positive lymph node, high histological grade, and advanced clinical stage. More studies with a huge sample size are needed to assess the prognostic role of MMPs in breast cancer. The use of MMP inhibitors as an adjuvant treatment for breast carcinoma is recommended.