CD46 Expression is an unfavorable prognostic factor in breast cancer cases.

The membrane cofactor protein, CD46 represents a complement inhibitor, which protects autologous cells from complement-mediated cytotoxicity. On tumor cells, CD46 may exhibit the potential to protect them from immune responses of the host. The present study aimed at evaluation of prognostic significance of CD46 expression in breast cancers. The analyses were performed on 70 samples of breast cancer. Immunohistochemical reactions were performed on paraffin sections of studied tumors using monoclonal antibodies directed against CD46. Results of the immunohistochemical reactions and of clinical observations were subjected to statistical analysis. Multivariate analysis showed that expression of CD46 and involvement of lymph nodes represent independent risk factors for disease-free survival and overall survival. Kaplan-Meier analysis showed that patients with tumors negative for CD46 have an increased progression-free time and overall survival time as compared with patients with the CD46-positive tumors. The study demonstrates that breast cancers manifest CD46 expression and that it is linked to a less favorable prognosis.