KCNN4 and sickle cell disease: The calcium-activated potassium channel, KCa3.1 is another druggable target and marker for cancer and vascular diseases and potent, specific KCa3.1 inhibitors have been tested both in vitro and in vivo for sickle cell anemia, malaria and stroke (Ataga et al., 2008; Chou et al., 2008; Tubman et al., 2015; Staal et al., 2017).