Abbreviations: AD, Alzheimer’s disease; PD, Parkinson’s disease; BC, breast cancer; IOs, ion channels; ASIC1, acid-sensing ion channel type 1a; Hv1, voltage-gated proton channel type 1.5; Nav1.5, voltage-gated sodium channel isoform 1.5; TME, tumor microenvironment; EC, extracellular space; GFs, growth factors; PDGF, platelet-derived growth factors. Here, SCN5A is linked to early-onset autosomal dominant Alzheimer disease.