SLC31A1 and in situ carcinoma: CIS is mostly taken up by renal tubular cells via copper transporter 1 (CTR1) and organic cation transporters 2 (OCT2) then pass through a number of bio-activation procedures that produce hazardous metabolites, that are catalyzed by -glutamyl transpeptidase (GGT) and cysteine-S-conjugate –lyase [19], [18].