Cysteine Cathepsins and Matrix Metalloproteases Among Breast Cancer Patients

BACKGROUND: Cellular proteases are thought to increase the likelihood of cancer cell infiltration and metastasis by degrading constituents of the extracellular matrix (ECM). Measuring activities of these proteases may be used as tumor markers for early diagnosis, prognosis, and as a possible target for treatment plan. OBJECTIVE: The aim of the current study is to evaluate cysteine cathepsins (CTSK and CTSL) and matrix metalloproteases-2 (MMP-2) and 9 (MMP-9) activities in human breast tumor tissue. METHODS: A comparative cross-sectional study plan was devised to study the enzymatic activities ofCTSK and CTSL andMMP-2 and MMP-9 via zymographic detection method. Sites of tissue sample collection were St Paul’s Millennium Medical College, Menelik II Hospital and Zewditu Memorial Hospital, Addis Ababa, Ethiopia. A total of 36 breast cancer patients were recruited and tissue samples were collected for the study. RESULTS: Activities of CTSK and CTSL were significantly elevated in cancerous tissue than the adjacent normal non-cancerous breast tissue of the same patients (n = 36, p ≤ 0.05). Also, activities ofMMP-2 and MMP-9 were increased significantly in tumor tissues than normal tissues (n = 36, P ≤ 0.05). CONCLUSION: It is found that there are different patterns of protease enzymatic activity expression between normal and tumor tissue using zymography. Compared with normal tissue samples, the protease enzymatic activity in cancerous tissue is higher. Thus, tissue proteases can be used in conjunction with histological techniques to identify patients in the same clinical group.