Although experimental studies have shown that these reversal agents can reverse tumor MDR, most previously studied inhibitors of ABC transporters are undergoing preclinical or clinical trials.[38, 47–49].As overexpression of ABC transporters in MDR cancers is strongly related to poor prognosis and dismal survival in cancer patients, suppressing ABC transporter function remains a viable strategy to potentiate anticancer efficacy of chemotherapeutic drugs and to reverse MDR. The gene discussed is ABCG2; the disease is cancer.