In this study, we found that #43, a novel GLUT1 inhibitor identified in our laboratory, synergized with cisplatin, a commonly used chemotherpeutic drug, not only in ER (+) MCF-7 cells but also in triple-negative MDA-MB-231 breast cancer cells which are usually more resistant to drug treatment (Figure 1). This evidence concerns the gene ESR1 and breast carcinoma.