Targeted blocking of EGFR and GLUT1 by compound H reveals a new strategy for treatment of triple-negative breast cancer and nasopharyngeal carcinoma.

BACKGROUND: Cytoplasmic epidermal growth factor receptor (EGFR) is overexpressed in both nasopharyngeal carcinoma (NPC) and triple-negative breast cancer (TNBC), while clinical outcome and prognosis vary greatly among patients treated with gefitinib, and all patients eventually develop resistance to this agent. Therefore, we propose a new concept for synthesizing multitarget compounds and reveal new therapeutic strategies for NPC and TNBC expressing EGFR.

METHODS: Compound H was synthesized in our previous study. Molecular docking and cell thermal shift assays (CETSAs) and drug affinity responsive target stability(DARTS) were used to confirm the binding of compound H to EGFR and GLUT1. Methylthiazolyldiphenyl-tetrazolium bromide(MTT), annexin V-PE assays, mitochondrial membrane potential (MMP) assays, and animal models were used to evaluate the inhibitory effect of compound H on TNBC cell lines. Energy metabolism tests, Western blotting, and immunofluorescence staining were performed to evaluate the synergistic effects on EGFR- and glucose transporter type 1(GLUT1)-mediated energy metabolism.

RESULTS: Compound H can simultaneously act on the EGFR tyrosine kinase ATP-binding site and inhibit GLUT1-mediated energy metabolism, resulting in reductions in ATP, MMP, intra-cellular lactic acid, and EGFR nuclear transfer. The anti-tumor activity of compound H is significantly superior to the combination of GLUT1 inhibitor BAY876 and EGFR inhibitor gefitinib. Compound H has remarkable anti-proliferative effects on TNBC MDA-MB231 cells, and importantly, no obvious toxicity effects of compound H were found in vivo.

CONCLUSIONS: Synergistic effects of inhibition of EGFR- and GLUT1-mediated energy metabolism by compound H may present a new strategy for the treatment of TNBC and NPC.