Immune interactions in breast cancer

Breast cancer (BC) is the most common cancer worldwide. It is composed of neoplastic cells, and other heterogeneous cell types found in the tumor microenvironment (TME), such as endothelial cells, stromal cells, and immune cells. These cells establish a very complex interplay with tumor cells, through a plethora of different mechanisms. These interactions strongly shape the TME, which plays a vital role in tumor onset and development, and the tumor itself. The TME composition is variable and evolving with tumor progression. Innate and adaptive immune cells in breast cancer TME can carry out immunostimulating or immunosuppressive activities, which favor or, conversely, antagonize tumor growth. The comprehension of the interactions that different immune cells establish with neoplastic BC cells can help widening our understanding of phenomena such as immunoediting, tumor resistance, and, in a broader sense, what is the molecular impact of the TME on tumor development. The aim of this thesis is to explore and gather the various functions that different cell populations, such as cells of the innate and adaptive immunity, perform when found in the TME and the impact of these functions on the tumor.