ABCG2 and metastatic colorectal cancer: Rs2231142 variant genotype has been reported to correlate with reduced in vivo intestinal transport capacity 34, high drug plasma in HIV-infected patients treated with dolutegravir 35, much greater plasma area under the concentration-time curve (AUC) values of sulfasalazine, a drug used as ABCG2 probe in vivo36, better low-density lipoprotein cholesterol-lowering efficacy of rosuvastatin in patients with hypercholesterolemia 37, and more favorite response rate of metastatic colorectal cancer to first-line chemotherapy 38.