MUC1 and cancer: The loss of cell polarity during cancer progression, and consequently, disorganization of components of cellular membrane results in displacement of MUC1 glycoprotein from apical surface in to whole membrane surface, which, in turn, triggers co‐localization of it with other types of transmembrane receptors including ICAM‐1, E‐selectin, EGFR, and erbB, as well as ECM components, which were not accessible before.