Under acidic extracellular conditions, other mechanisms of net acid extrusion—particularly, transport via the Na+/H+-exchanger NHE1 [59]—are markedly inhibited, and cellular acid loading through potential H+ leaks will be accelerated, which can explain the stronger anti-cancer consequences of inhibiting NBCn1 at pHo 6.8 compared to 7.4. The gene discussed is SLC9A1; the disease is cancer.