ABCC1 and colonic neoplasm: Finally, 10 μM of GS-9973 did not remarkably reverse the drug resistance of 1) SW620/AD300 colon cancer cells, which have high expression of the ABCB1 transporter, to doxorubicin (Figure 3B), 2) 3 μM of GS-9973 did not modify the efficacy of the anticancer drug, vincristine in HEK293/ABCC1 cells, which overexpress the ABCC1 transporter (Figure 3D).