Expression of matrix metalloproteinase 2 (MMP-2), E-cadherin and Ki-67 in metastatic and non-metastatic canine mammary carcinomas

摘要

Background The aim of the study was to demonstrate the immunohistochemical expression of proteins that affect the metastatic potential of a tumour, including matrix metalloproteinase 2 (MMP-2) and E-cadherin. Another objective was to determine their correlation with the expression of the Ki-67 antigen in metastasizing and non-metastasizing mammary carcinomas in female dogs. The study was conducted on 32 canine mammary carcinomas (12 metastatic and 20 non-metastatic), classified as simple tubular and tubulopapillary carcinomas. Immunohistochemistry was performed to evaluate the expression of MMP-2, E-cadherin and Ki-67 antigen. Results MMP-2 was expressed in 85?% of the non-metastatic tumours and in all the metastatic tumours, while E-cadherin was expressed in 85?% of the non-metastatic tumours and in 66?% of the metastatic tumours. The Ki-67 antigen was expressed in 65?% of the non-metastatic tumours and in 91?% of the metastatic tumours. The mean Ki-67 expression was slightly higher in tumours that had metastasized (1.5?±?0.90 vs 1.1?±?0.94; p =?0.22). A similar relationship was found in terms of the intensity of the MMP-2 expression (2.9?±?1.9 vs 2.7?±?2.4; p =?0.50). A decrease in the expression of E-cadherin (2.8?±?2.5) was found in metastatic tumours compared to the expression in non-metastatic tumours (3.2?±?2.3). However, these differences were not statistically significant ( p =?0.63). Conclusion We did not show significant differences in MMP-2, E-cadherin and Ki-67 expression between metastatic and non-metastatic tumours due to low number of cases studied, however further experiments are necessary to assess the role of these antigens in the process of canine mammary tumours metastasis.