Currently, there has been an increasing number of studies which reports that the Hv1 proton channel has a key role in proton extrusion in tumor cells, relating their overexpression in some cases to tumor malignancy (Wang et al., 2011; 2012; 2013b; Yu et al., 2014; Asuaje et al., 2017) (Figure 4). Here, HVCN1 is linked to neoplasm.