There were 76 proteins detected only in the AQP1-overexpressing group, including proteins reported to exert prosurvival and/or prometastatic activities in breast cancer, such as intercellular adhesion molecule 1 (ICAM1) [23, 24], cathepsin S (CTSS) [25, 26], and PLAT [27] (Supplementary Fig. 5b). Here, AQP1 is linked to breast cancer.