Organic cation transporter 2 (OCT2) has been implicated in cisplatin nephrotoxicity in a study with isolated human proximal tubules [24], and hypomagnesemia results in up-regulation of OCT2 and thereby increases the renal accumulation of cisplatin and exacerbates acute kidney injury in an animal model [25]. Here, SLC22A2 is linked to familial primary hypomagnesemia.