ABCG2 and neoplasm: Importantly, 68Ga-Galmydar is also recognized by ATP-binding-cassette (ABC) family of transporters, such as ABCB1 (also known as P-glycoprotein, 170 kD protein located on plasma membrane of tumor cells) and ABCG2 (also known as breast cancer resistance protein, BCRP, 72 kD protein) as their transport substrate [32].