LL-37 (13-37) is an anticancer peptide fragment of LL-37 .[1] It inhibits the ATPase activity of ATP-binding cassette transporter 2, subfamily G (ABCG2) when used at a concentration of 1 µM. LL-37 (13-37) induces cytotoxicity in wild-type SW620 cells and SW620 cells overexpressing P-glycoprotein (P-gp), also known as multidrug resistance protein 1 (MDR1; IC50s = 25.5 and 27.3 µM, respectively), as well as wild-type MCF-7 cells, MCF-7 cells overexpressing ABCG2, and MCF-7 cells overexpressing multidrug resistance-associated protein 1 (MRP1; IC50s = 33.1, 31.8, and 31.1 µM, respectively). It potentiates cytotoxicity induced by mitoxantrone in MCF-7 and HEK293 cells overexpressing ABCG2 when used at concentrations of 5 or 10 µM but not cytotoxicity induced by cisplatin in HEK293 cells overexpressing ABCG2, paclitaxel in SW620 cells overexpressing P-gp, or doxorubicin in MCF-7 cells overexpressing MRP1 at the same concentrations. LL-37 (13-37) (10, 20, or 40 µM) decreases mitoxantrone drug efflux by, and increases mitoxantrone levels in, MCF-7 cells overexpressing ABCG2.
References:
[1].To, K.K.W., Ren, S.X., Wong, C.C.M., et al.Reversal of ABCG2-mediated multidrug resistance by human cathelicidin and its analogs in cancer cellsPeptides4013-21(2013).