PROS1 and breast cancer: SOX2 overexpression increased breast cancer stem cells by activating the Wnt signaling pathway, resulting in drug resistance.[34] Intercellular adhesion molecule‐1 (ICAM‐1) is considered as the transmembrane‐protein complexes, and its overexpression is a driving factor of breast cancer, as it participates in the recognition and adhesion between adjacent cells.[35] Inhibition of ICAM‐1 expression could significantly reduce MCF‐7 cell drug resistance.