SLC9A1 and cancer: Previously described small molecule inhibitors of NBCn1 (e.g., S0859) do not provide the selectivity or pharmacokinetic properties necessary for systemic therapy (Boedtkjer et al., 2012; Larsen et al., 2012; Steinkamp et al., 2015); and whereas NHE1 inhibitors (e.g., cariporide, eniporide) reached phase 3 clinical studies for ischemic heart disease (Mentzer et al., 2008; Zeymer et al., 2001), they have not been sufficiently explored for cancer therapy.