SLC9A1 and cancer: Finally, there are many reasons to think that any of these new and potent NHE1 inhibitors could have a significant selectivity in the treatment of cancer, since even if NHE1 is ubiquitous and plays a fundamental role in pH housekeeping and volume control, it is also well known that in normal tissues the NHE1 is quiescent and is activated only during acidosis or cell shrinkage.