Targeting tumour-associated macrophages in primary and metastatic breast tumours

Abstract

Cancer is the second leading cause of deaths worldwide. In 2018 there were estimated to be around 17 million new cancer cases world-wide, of which breast cancer is the most common cancer among women. Breast cancers are divided into subtypes based on the markers they express on the cancer cell’s surface. The most dangerous breast cancer subtype is triple negative breast cancer (TNBC), which does not express any hormonal receptors that current therapies can target. Therefore, there is no therapy option for TNBC patients. In this thesis, the evaluation of the use of a peptide (called mUNO) that targets an immune cell population with major protumoural roles, M2 tumour-associated macrophages (M2 TAMs), is shown. mUNO was validated in vitro using primary human M2-differentiated macrophages, and in vivo using two different mouse models of TNBC. It was shown that mUNO binds specifically to the M2 TAMs both in vitro and in vivo. The findings presented here may have implications for clinical management of the TNBC.