ABSTRACT
The search for a simple, sensitive test to reliably determine prognosis and predict response to therapy in patients with cancer is an important area of translational research. The Her-2/neu oncogene and its receptor protein overexpression are indicators of more aggressive form of breast cancer. Her-2/neu overexpression was involved in cell differentiation, proliferation, migration and carcinogenesis. The main target of this study is to investigate the possible correlation between tissue Her-2/neu, serum Her-2/neu extracellular domain [ECD] and MMP-9. The impact of the assayed parameters on the disease free survival [DFS] in breast cancer patients will also investigated after one year of follow up. Serum was collected from 33 breast cancer patients and 10 healthy volunteers. Serum Her-2/neu ECD was detected by enzyme linked Immunosorbent assay [ELISA] and serum MMP-9 was detected by enzyme Immunoassay [EIA]. Patients were reevaluated after one year of follow up to detect disease relapse. Positive correlation between expression of Her-2/neu in the primary tumor tissue and the circulating serum Her-2/neu ECD was detected. Serum Her-2/neu ECD was more sensitive in predicting disease free survival than tissue Her-2/neu. Positive correlation between expression of Her-2/neu in the primary tumor and serum MMP-9 was also observed. In contrast, negative correlation between circulating serum Her-2/neu ECD and serum MMP-9 was detected in patients with tissue positive Her-2/neu. We also observed that MMP-9 was a good monitoring factor for the chemotherapy response. We concluded that serum Her-2/neu ECD might be a good prognostic parameter in addition to tissue Her-2/neu and MMP-9 might be the member of MMPs family that responsible for the shedding of the ECD of Her-2/neu receptor