GSH excreted in the blood is cleaved, to its constituents; and de novo synthesis of GSH by cancer cells occurs as follows: GSH is first exported from the cell of origin via transporters known as Multiresistance Drug Proteins (MRPs), which belongs to the ATP binding cassette (ABC)s transporter family and is well-known player in cancer resistance mechanisms (33). Here, ABCB6 is linked to cancer.