AQP4 and breast carcinoma: AQP4 knockdown in human breast cancer was associated with increased levels of E-cadherin, and in glioma cells with increased β-catenin (involved in actin reorganization and cell-cell adhesion) and connexin-43 (a gap junction protein that contributes to cell-cell signaling and adhesion) (Ding et al., 2011; Li Y. et al., 2016), suggesting AQP4 might enhance cell detachment from primary tumors.