10565 Background: Tumor cell recognition by NK cells is mediated by the interaction of activating and inhibitory NK cell receptors with their ligands expressed on tumor cells. In addition, NK cells express adhesion molecules that facilitate formation of the immunological synapse with the tumor targets. Here, we investigated whether the coordinate expression of NK activating receptors and adhesion molecules could provide a signature to segregate breast cancer patients into relapse and relapse-free outcomes. Methods: Gene expression profiling, RT-PCR screening and survival analysis were performed on RNA extracted from primary breast cancers. Tumors were obtained from patients experiencing either 5-8 years relapse-free survival or tumor relapse within 1-3 years following initial treatment. Results: Tumors from patients with a favorable prognosis were characterized by increased expression of genes involved in NK cell interaction with tumor cells and its activation signaling. In particular, up-regulation of Natural Cytotoxicity Receptors (NCRs), leukocyte function-associated antigen 1 (LFA-1), CD226 (DNAM-1) and CD96 was observed in relapse-free patients. Thus, the expression of the NK activating receptors and relevant adhesion molecules involved in NK cell:target interactions can predict relapse free survival in breast cancer patients. Conclusions: Results from the present study, highlighted the effector cooperation between the innate and adaptive immune components within the tumor microenvironment. The NK cells parameters identified in this study, together with the prognostic B and T cell signatures previously reported by us, represent a powerful tool for predicting breast cancer outcome which might be easily introduced in clinical practice.
Identifying breast cancer patients at risk for Central Nervous System (CNS) metastases in trials of the International Breast Cancer Study Group (IBCSG)
