SLC9A1 and triple-negative breast carcinoma: We used specific NHE1 inhibitors, HMA [5-(N,N-hexamethylene) amiloride)], representative of the pyrazine class of amiloride derivatives, and EMD87580 [2-methyl-4,5-di-(methylsulfonyl)-benzoyl-guanidine)], representative of the benzoylguanidines, to increase the susceptibility of triple-negative breast cancer cells to paclitaxel.