ABCB1 and colon carcinoma: For instance, ABCB1 gene was overexpressed in SW620 colon carcinoma and CEM-Bcl2 cells exposed to TSA (Jin and Scotto, 1998; Baker et al, 2005), or KU812 and NB4 cells exposed to depsipeptide (Tabe et al, 2006; Yamada et al, 2006).