This is achieved by increased ATP-binding cassette (ABC) membrane transporters (such as MDR1), ABC sub-family G member 2/3 (ABCG2/3), and ABC sub-family C member 2/4/5 (ABCC2/4/5), which are downstream of the cancer stemness-related genes SNAIL, SLUG and TWIST [114,115,116,117,118]. Here, ABCB6 is linked to cancer.