The observation that apparently adjacent non-neoplastic mucosa expresses other antigens involved in cancer progression (e.g., EMT) is supported by a study demonstrating EMT markers (α-smooth muscle actin & SNAIL) and EMT-inducers (MMP2 & TGF-β3) are extensively expressed in histologically normal tissues proximal to breast tumour margins (i.e.,  = 1 cm away) whilst being only sparsely expressed at a distance of 5 cm from the same tumour margins [36]. Here, MMP2 is linked to cancer.