Impacto clínico-biológico de la positividad de la pS2 en carcinomas ductales infiltrantes de mama receptor de estrógenos negativos

Abstract

The pS2 protein is regulated by estrogens, but it can also be expressed in hormone independent breast carcincomas. We have carried out the present study in order to analyze the clinical-biological impact of pS2 positivity (>2 ng/mg prt.) in negative estrogen receptors (< 10 fmol/mg prt.) infiltrating ductal breast carcinomas (IDC). 97 negative ER-IDC have been included in our study. We established the doses of the cytosol levels of pS2, progesterone receptors (PR), cathepsin D, tissue -type plasminogen activator (t-PA) and hyaluronic acid (HA), as well as the levels of HA, epidermal growth factor receptor (EGFR), CD44v5 and CD44v6 in cell surface membranes. We also considered the menopausal status, histological grade, ploidy, cellular synthesis phase, tumor size, axillary lymph node involvement and the existence of distant metastasis. The same results were obtained when the progesterone receptor status was also considered. ER-/pS2+ IDC presented higher (p <0,05) PR, t-PA and HA cytosol level, as well as lower EGFR concentrations, S-phase > 7% and S-phase >14% and lower N+>10 percentages and aneuploidy. They were also more frequently CD44v6+. The same results were observed when the positivity of the progesterone receptors was considered. The above results lead us to consider that the positivity for pS2 in ER- IDC is associated with hormone-dependent parameters, good differentiation and lower cellular proliferation, which can explain a better clinical outcome.